Cards from USMLE-Rx (First Aid) Flashcards
1
Q
What is the first step to manage increased ICP in a patient who has lost consciousness and has a suspected intracranial hemorrhage
A
Intubate and ventilate the patient to protect the airway.
2
Q
How can a child inherit two copies of an allele from the same parent?
A
Uniparental disomy due to nondisjuction I/II error
3
Q
What is the neuropathology shown on the image?
A
Lewy bodies, seen in Lewy Body dementia or secondary to Parkison’s
4
Q
What autoantibodies could cause a macrocytic anemia?
A
Pernicious anemia due to autoantibodies to gastric parietal cells causing malabsorption of vitamin B12. Often co-occurs with Hashimoto’s
5
Q
What types of cancer are associated with hereditary loss of function of the RB1 gene?
A
Retinoblastoma, osteosarcoma, melanoma, brain cancer.
6
Q
What is the mechanism of action of Octreotide? What conditions does it treat?
A
It is a somatostatin analogue used to treat esophageal varices, acromegaly, carcinoid syndrome, VIPomas.
7
Q
How do you distinguish between disseminated intravascular coagulation (DIC) and immune thrombocytopenic purpura on labs?
A
DIC will have thrombocytopenia AND elevated INR and elevated PTT, whereas the most commonly for ITP there will only be isolated thrombocytopenia (platelets <150,000/mm^3)
8
Q
Where are the LMNs located in the spinal cord?
A
In the anterior horns.
9
Q
What is the function of oxyphils and where are they located?
A
Oxyphils are present in the parathyroid gland and may contribute to PTH secretion (but classically PTH is secreted by parathyroid chief cells).
10
Q
What changes to thyroid hormone occur in pregnancy? What is the mechanism of these changes?
A
Overall, pregnant persons remain euthyroid because even though estrogen stimulates liver synthesis of thyroxine-binding globulin, which in turn leads to more total T4, but the amount of free T4 remains the same.
11
Q
What finding on urinalysis indicates kidney involvement (pyelonephritis)?
A
WBC casts
12
Q
What is the most common cause of cancer mortality in the US?
A
Lung Cancer
13
Q
What organism would cause characteristic “crackling” on palpation of a swollen, tender, red injured area?
A
Clostridium perfirindens; crackling comes from the subcutaneous gas production; the bacteria produces a phospholipase which cleaves lecthin in plasma membranes of cells.
14
Q
A presentation of bilateral juvenile cateracts and bilateral hearing loss suggests which condition?
A
Neurofibromatosis type 2 (NF-2), due to a LoF mutation on chromosome 22, increasing the risk of multisystem cancer.
15
Q
What is the location of the major blood supply to the uterus?
A
The uterine arteries and veins run along the cardinal ligament of the uterus attaching to the uterine walls above the level of the cervix.
16
Q
How is gout and pseudogout differentiated on microscopy of arthrocenteis?
A
Gout = negatively birefringent needle-shaped crystals.
Psudogout = positively birefringent rhomboid crystals.
17
Q
What glomerular abnormalities would be consistent with Henoch-Schonlein Purpura (HSP)?
A
Presence of mesangial IgA deposits.
18
Q
What study type could be used to calculate relative risk for developing a given disease based on exposures?
A
Prospective cohort study.
19
Q
Elevated levels of ketoacids in a newborn with neurologic symptoms is suggestive of what condition?
A
Maple Syrup Urine Disease—caused by deficiency in branched-chain alpha-ketoacid dehydrogenase leading to inability to metabolize isoleu, leu and val.
20
Q
What is the mechanism of action of Flucytosine?
A
It is converted to 5-FU in fungal cells, thus interfering selectively with fungal DNA synthesis.
21
Q
How do glucocorticoids block inflammation?
A
By inhibiting phospholipase A2, which stops the production of arachidonic acid, which acts downstream to cause prostacyclin and prostaglandin release.
22
Q
Which bugs are the top causes of PID?
A
Chlamydia trachomatis and Neisseria gonorrhoeae
23
Q
What class of GPCR receptors could contribute to postural hypotension? What is the mechanism of action?
A
alpha-1 (a1) receptor blockade, with resultant decrease in phospholipase C and decrease in calcium release. A1 vasoconstricts, B2 vasodilates.
24
Q
What symptoms suggest giant cell arteritis? What is GCA often accompanied by?
A
Polymyalgia rheumatica (fatigue and stiffness esp with proximal muscle weakness in hip and shoulder) often accompanies GCA; GCA symptoms include unilateral headache and vision changes (classic patient is older female).
25
Name one way that cancer cells can escape immune detection.
MHC-I downregulation (note that MHC II downregulation does not play a role in immune evasion in cancer).
26
Which phospholipid is missing in neonatal respiratory distress syndrome?
phosphatidylcholine—the primary component of pulmonary surfactant?.
27
Pesticide exposure (organophosphates) would lead to what kind of symptoms? How would these be treated?
Symptoms: DUMBBELLS (diarrhea, urination, miosis, bronchospasm, bradycardia, excitation of skeletal muscle, lacrimation, sweating, salivation (cholinergic excess, is wet). Treated with atropine which blocks muscarinic receptors and pralidoxime in addition to binding and displacing the organophosphates from acetylcholinesterases.
28
What is a differential for a rash which begins initially on the soles and palms?
1. Rocky Mountain spotted fever (caused by Rickettsia ricketsii, transmitted by ticks)
2. Meningococcemia
3. Secondary syphilis
29
What organism is associated with Guillain Barre Syndrome? What are its chacteristics?
Campylobacter jejuni: grows hot (42C), is a gram negative, S shaped, oxidase positive.
GBS -\> rapidly progressive, ascending paralysis with muscle weakness originating in the distal lower extremities.
30
What is a hapten?
A hapten is a moleule which can only activate an immune response when it is bound by a protein (e.g. in penicillin induced autoimmune hemolytic anemia).
31
Which opioid receptors are responsible for the effects of heroin?
mu-receptors.
32
What is the characteristic rash in impetigo? Which organism(s) cause it?
Impetigo is either bullous (Staph aureus) or nonbullous (Group-A Strep OR staph aureus). The classic rash is erythematous with multiple vesicles which produce honey-coloured plaques on rupture.
33
Polyomavirus JC / JC virus presents in which population and with what symptoms?
JC virus can cause progressive multifocal leukoencephalopathy in patients which are immunosuppressed.
34
What changes on labs are expected in disseminated intravascular coagulation?
Decreased platelet count, higher bleeding time, prothrombin and partial thromboplastin (PT/PTT) time.
35
What are findings on urinalisys for post-strep glomerulonephritis? (or nephritic syndrome more generally)
hematuria (may have RBC casts), HTN, edema, moderate but not crazy (3.5g+) proteinuria.
36
What would explain a paradoxical high TSH and high T3 level in the context of low iodine uptake?
Exogenous levothyroxine (causing thyrotoxicosis factitia).
37
What are classic findings on light microscopy from a kidney biopsy in a patient with Goodpasture's Syndrome?
Auto antibodies against collagen IV in glomerular basement membranes leading to glomerulonephritis (crescent formation + fibrosis). This is a nephritic
38
How would you clinically differentiate between spontaneous pneumo and tension pneumo?
Tension pneumo is typically associated with trauma to the chest wall which will develop tachycardia and tachypnea and eventually cardiac arrest. As well, the trachea should deviate away from the pneumo and there will be increased JVP.
39
What are the symptoms and associated organisms for reactive arthritis?
Typically occurs 2-3w post-infection with Shigella, yersinia, chlamydia, campylobacter, salmonella. Symptoms include asymmetric seronegative oligoarthritis, coupled with conjunctivitis and urethritis (can't see, can't pee, can't bend my knee).
40
What is the impact of prostaglandin E2 on renal perfusion?
PgE2 causes afferent vasodilation.
41
What are some examples of anti-VEGF therapies? What diseases do they treat?
1. Macular degeneration (ranibizumab, pegaptanib, aflibercept)
2. colon, breast, non-small cell lung cancer (bevacizumab)
42
Which viruses contain hemagglutinin?
Influenza viruses and measles virus.
43
What is the mechanism of activity of digoxin?
Na+intracellular concentrations increase because digoxin inhibits Na/K pump. As Na+ increases, it inhibits Na/Ca++ pump activity, causing intracelullar concentrations of Ca++ to rise (increasing contractility).
44
What is the most common cause of hereditary thrombophilia?
factor V Leiden mutation, causing inability of protein C to inactivate factor V, leading to continuous activation of coag pathway.
45
What pituitary condition is associated with postpartum fatigue, weight loss, amenorrhea and failure to breastfeed?
Sheehan syndrome (postpartum hypopituitarism) -\> global decrease in prolactin, GH, FSH/LH, TSH, ACTH
46
Necrotic inflammatory infiltrate and giant cells on a bone biopsy is characteristic of...?
Extrapulmonary tuberculosis of the spine (Pott disease).
47
For prolonged (10y+) alcohol use disorder, what signs are expected on brain imaging?
Cerebellar degeneration leading to ataxia
48
What are the indications and mechanism of action of macrolides?
Macrolides include azithromycin, clarithromycin and erythromycin. They work by inhibiting protein synthesis by binding 23S rRNA of the prok 50S ribosome, blocking the P site. Indications are atypical pneumonia, Chlamydia, Gram+ cocci for pts allergic to penicillin and pertussis.
49
What are the indications and side effects of ribavirin?
Ribavirin is used to treat RSV, hep C and some viral hemmhorragic fevers. It can cause a hemolytic anemia
50
What are the diagnostic criteria for rheumatic fever?
Migratory polyarthritis, pancarditis, subcutaneous nodules, erythema marginatum (pink rings on torso and inner surface of limbs), sydenham chorea., elevated ASO (anti-streptolysin O) titre..cardiac biopsy indicates insterstitial myocardial granulomas.
51
What extra heart sounds might be heard in a patient who had acute rheumatoid fever?
Mitral valve stenosis: an opening snap with a diastolic rumble best appreciated over the Mitral area.
52
What is the classic presentation and causative organism of karposi sarcoma?
KS is caused by human herpesvirus 8; it is an AIDS-defining illness with firm palpable purple maculopapular rashes.
53
How does liver cirrhosis lead to lowered platelet count?
Portal hypertension -\> splenomegaly -\> entrapment of platelets.
54
What is a classic presentation of prolactinoma?
Bitemporal hemianopia with diminished libido, worsening headache, gynecomastia and ED in men, decreases in muscle mass, body hair and osteopenia.
55
What is the mechanism of action of bleomycin?
Bleomycin causes DNA breakage leading to G2 arrest.
56
Which phase of the cell cycle is affected by vincristine and paclitaxel?
M phase—paclitaxel *promotes* microtubule stabilization, vincristine destabilizes micotubules.
57
What is leucovorin?
Leucovorin is folinic acid, the active metabolite of folic acid. It is used to counter myelosuppression (i.e. methotrexate).
58
What is the location of the lesions and the characteristic presentation of Korsakoff psychosis?
Korsakoff psychosis presents as anterograde amnesia, confabulation, personality changes. Lesions occur to the mammillary bodies (part of the limbic system). It is caused by thiamine deficiency (vitamin B1)
59
What is the natural reservoir and presentation of hantavirus?
Hantavirus infects the deer mouse; mouse dropping and urine are primary vectors for human infection. Presentation is fever, headache, myalgia, GI upset, dizziness and chills progressing to pulmonary edema, cough and respiratory distress.
60
What electrolyte changes are expected in a thiazide diuretic?
Thiazide diuretics cause hypokalemia, metabolic acidosis, hyperglycemia, hyperlipidemia, hyperuricemia and hypercalcemia due to the blockage of Na+/Cl- reabsorption in the early distal convoluted tubule.
61
What is the classification for C diff? Which toxins does it produce?
Gram-positive spore-forming anaerobe; produces toxin A (diarrhea causing) and toxin B (cytoxic)
62
The fusion of which embryonic structures creates the palate?
The palatine processes.
63
Which conditions lead to elevation of Anti-Jo-1 antibodies?
Anti-Jo-1 are specific myositis and are directed against histidyl-tRNA-synthetase.
64
What is the first line treatment for mild oral thrush?
Nystatin swish and swallow.
65
What are risk factors for hepatocellular carcinoma?
cirrhosis (alcohol abuse), hep B/C, FH, and aflatoxin (produced by Aspergillus flavus, a peanut and grain mold).
66
Which hormone can sometimes be elevated in small-cell lung cancer?
ADH
67
What is crigler-Najjar syndrome Type I?
Caused by mutations to UDP-glucuronosyltransferase, leading to inability to conjugate bilirubin. Eventually will proceed to kernicterus (bilirubin deposits in the brain leading to encephalopathy).
Type I is more severe, type II responds to phenobarbital.
Liver transplant = cure.
68
What is the classic presentation of BCC?
BCC presents as raised pearly borders surrounded by telangiectasias;
69
Which receptors are targeted by benzodiazepines? What drug would you give in an overdose? What is its mechanism of action?
GABA-A receptors; flumazenil, a competitive antagonist.
70
What is a risk factor for SCC of the bladder in sub-Saharan Africa?
Helminth infection due to chronic irritation from the eggs of Schistosoma haematobium.
71
What enzyme deficiency would explain weight loss, lethargy and disphoresis in an infant who has recently been introduced to fruit juices?
Aldolase B, the enzyme that converts fructose-1-phosphate to substrates for gluconeogenesis. A buildup of f1-p inhibits gluconeogenesis, leading to hypoglycaemia.
72
What is the most worrisome side effect of doxorubicin
Dilated cardiomyopathy
73
What are common symptoms of (mlld vs severe) hypocalcemia?
Mild: parasthesia, muscle cramps and perioral numbness.
Severe: carpopedal spasm, seizures, tetany.
74
How would you prevent hemorrhagic cystitis caused by cyclophosphamide?
Use of mesna (which provides a free thiol which binds and inactivates acrolein, an unwanted cytotoxic metabolyte respondsible for the hemorrhagic cystitis). May also be helped by increasing fluid intake.
75
Which GPCRs are targeted to treat asthma? What is the mechanism of action?
The Gs pathway is activated by a B2-agonist, such as albuterol; this leads to adenylyl cyclase activation, PKA activation and phosphorylation of myosin light chain kinase, which inactivates MLCK and causes smooth muscle relaxation (bronchodilation).
76
What are the long-term sequellae of untreated syphilis
Aortic insufficiency due to destruction of the vasa vasorum (blood vessel supply) of the ascending aorta.
77
What is the indication and mechanism of action of Zileuton?
Zileuton is used for chronic asthma and functions by inhibiting 5-lipoxygenase, which converts arachidonic acid into leukotrienes (potent bronchoconstrictors).
78
Which cranial nerves are affected by a vertebral artery or posterior inferior cerebellar artery dissection / thrombosis?
Lateral medullary syndrome: CN IX, X and XI (sparing XII since it is medial) leading to hoarseness or dysphagia. Also affects descending sympathetic fibres resulting in ipsilateral horner syndrome.
79
What symptomology should make you question a mania / bipolar I disorder diagnosis?
Normal sleeping (7+ hours), depression (not required to make a type I diagonsis), euthymic (not elated or expansive).
80
What is the cause and presentation of thrombotic thrombocytopenic purpura?
Cause is inhibition or congenital defect in ADAMTS13, an enzyme which breaks down large vWF multimers. Presentation is fever, Schistocytes (microangiopathic hemyolytic anemia), and thrombocytopenia, with normal PT and PTT, neurologic symptoms, acute kidney injury.
81
Elevated serum levels of amylase would suggest infection with which organism?
Something that causes parotitis, e.g. mumps.
82
What is the territory of the blood supply for the superior mesenteric artery?
Inferior pancreaticoduodenal artery -\> head of pancreas and ascending and inferior duodenum
Branches to ileum and jejeunum,
Ileum, cecum and appendix (via ileocolic)
Right colic to ascending colon
Middle colic to transverse colon.
83
What is the indication and mechanism of action for montelukast?
Montelukast is a leukotriene receptor inhibitor (blocking bronchospasm without affecting leukotriene production).
84
How do you distinguish between epidural hematoma vs subdural hematoma?
Epidural hematoma occurs via rupture of the middle meningeal artery. Presents with a lucid interval followed by rapid deteroration and with a **"lens-like" defect on CT, does not cross suture lines).**
Subdural hematoma is due to rupture of bridging veins, gradual onset, **crescent-shaped hemorrhage that crosses suture lines.**
85
What enzyme defect would result in an infant with general weakness, a palpable liver and an enlarged cardiac silhouette on x-ray
lysosomal acid alpha-1,4-glucosidase; leading to accumulation of glycogen in the heart, liver and muscle.
86
What vitamin do hepatic satellite cells store?
Vitamin A
87
A t(14,18) translocation leads to overexpression of what gene?
BCL-2; prevention of apoptosis.
88
What is the pathogenesis of a syndrome involving blanching skin above the clavicle with erythema bilaterally in the upper limbs, face and neck?
SVC syndrome, could be a cancerous obstruction, venous thrombosis from indwelling catheter or hilar granuloma.
89
How are bronchiectasis and secondary TB differentiated on histology?
Bronchiectasis -\> necrotizing inflammation with dilated bronchial tissue
secondary TB is caseating granulomas with central necrosis.
90
How would you differentiate between a CML and a lymphoma?
CML -\> myeloid cells (neutrophils, macrophages); a lymphoma would present with lymphadenopathy, small round blue cells interspersed with nonmalignant macrophages on splenic biopsy.
91
cells with giant granules on blood smear could indicate a defect in which gene?
LYST (the lysosomal trafficking regulator gene) -\> phagocyte dysfunction; Chediak-Higashi syndrome.
92
UV-based DNA damage requires which repair pathway?
Nucleotide excision repair
93
What is a classic presentation of sarcoidosis?
Resp symptoms + elevated ACE; CXR shows bilateral hilar lymphadenopathy and infiltrates. Erythema nodosum (bilateral tender red bumps on the shins). Treat with steroids.
94
How do you reverse heparin?
Proteamine sulfate (binds to negatively charged heparin)
95
What is the causative organism for a fishy-smelling vaginal odour with homogenous gray-white discharge without urethritis or cervicitis?
Gardnerella vaginalis; gram-variable pleomorphic rod.
96
What is the most common cause and characteristic presentation of B12 deficiency?
Pernicious anemia due to gastric parietal cell atrophy (lack of intrinsic factor). Presents as glossitis, and ascending motor and sensory loss in lower limbs, with macrocytic anemia.
NOT commonly dietary deficiency.
97
Does a decrease in cooperative oxygen binding cause a shift in the hemoglobin binding curve?
No.
98
What is the difference between direct inguinal hernia and indirect inguinal hernia? Which populations are they most common in?
Direct -\> peritonium goes through the abdo wall into the inguinal triangle (common in older men).
Indirect -\> peritoneum goes through the deep inguinal ring into the scrotum (common in male infants)
99
Which drugs and disease inhibit platelet aggregation via interference with GpIIIb/IIIa?
Abciximab, eptifibatide, tirofiban
Glanzmann thrombasthenia
100
What defense mechanism is associated with borderline personality disorder?
Splitting (ie. either/or classification of things as all good and all bad)
101
A glucose-6-phosphatase deficiency would present as...?
von Gierke disease, hepatomegaly, hypoglycemia, seizures, lactic acidosis, hypertriglyceridemia and hyperuricemia.
102
What is the mechanism of action of sildenafil?
They inhibit PDE-5, which causes enhanced smooth muscle relaxation due to the nitric oxide. They do not increase NO levels.
103
What is the pathogenesis of the following lesion?
Staphylococcal scalded skin syndrome; Staph aureus releases an exotoxin which binds desmoglein-1 and interferes with desmosomes.
104
What is libman-sacks endocarditis?
SLE -\> nonbacterial thrombotic endocarditis, generally does not cause valve dysfunction or fever, emboli are composed of neutrophils, lymphocytes, fibrin and histiocytes.
105
A congenital pancytopenia with bony abnormalities is suggestive of....?
Fanconi anemia
106
Which nerve innervates the scrotum and medial thigh?
Ilioinguinal nerve (runs into the inguinal canal via the top of the spermatic cord).
107
What is the mechanism of action of beta-blockers for HTN?
Decrease in renin production by blocking beta-adrenergic receptors (which normally release renin in response to sympathetic stimulation).
108
What changes on PFT are expected in COPD?
Decrease in FEV
Decrease in forced Vital Capacity (FVC)
Decreased FEV1:FVC ratio
Increased Total Lung Capacity (TLC)
109
What is the mechanism of action of benzodiazepines?
Increased Cl- channel opening frequency in response to GABA.
110
What is the pectinate line?
The junction of endoderm and ectoderm just under the anal valves.
111
What receptor type mediates glucagon's actions?
A GPCR (adenylyl cyclase -\> cAMP); think fasted state (so "low energy").
112
What is the mechanism of action of cyclophosphamide?
Cross-links DNA at guanine (alkylates)
113
What is the classic presentation and pathogenesis of Kartagener syndrome?
Bronchiectasis (with associated resp infections), inability to auscultate S1 and S2, situs inversus.
Kartagener syndrome is caused by a dynein arm defect that results in immotile cilia -\> infertility.
114
When should you suspect multiple endocrine neoplasia type I?
Pituitary parathyroid and pancreatic (endocrine) tumors.
115
What kind of tumor would present as WHDA syndrome?
Watery Diarrhea
Hypokalemia
Achlorhydria
a VIPoma (vasoactive intestinal polypeptide) originating from the pancreas.
116
How does a meckel diverticulum appear most commonly on a technetium-99 scan?
Periumbilical area.
117
What is DHEA short for?
Dehydroepiandosterone.
118
What is the tumor marker most commonly found in hepatocellular carcinoma?
Alpha-fetoprotein.
(also found in yolk sac germ cell tumors)
119
Describe the order of the "zones" of the adrenal gland and associated hormone from the outside in.
Capsule
Zona **glomerul**osa - aldosterone
Zona fasciculata - cortisol and some sex hormones
Zona reticularis - sex hormones
Medulla - Catecholamines
120
What serum abnormalities would be found in post-strep glomerulonephritis?
Elevated creatinine, decreased C3 levels (due to complement activation).
121
What is the most common causative organism for otitis externa (swimmer's ear)
Pseudomonas aeruginosa (gram-neg, rod-shaped)
122
What is the mechanism of action of cocaine?
It is an indirect sympathomimetic, functions by inhibiting reuptake of dopamine, norepinephrine and serotonin specifically targeting the nucleus accumbens.
123
How does cardiac tamponade present clinically? On ECG?
Beck triad: hypotension, distended neck veins, distant heart sounds, tachycardia with pulsus paradoxus.
ECG would show low-voltage QRS with different amplitudes.
124
What would explain a presentation of bone pain, headache, tinnitus, vertigo and hearing loss? What would you expect on labs?
Paget disease (abnormal bone remodelling with incraesed osteoclastic followed by osteoblastic activity). Increased alkaline phosphatase on lab.
125
Why would esmolol be preferred over metoprolol in acute arrhythmia?
Esmolol has a much shorter half life (9 minutes!) so it is good to trial if beta-blocker would be tolerated esp in a pt with cardiac conditions.
126
What is the drug class of choice for treating hypertriglyceridemia?
Fibrates e.g. gemfibrozil (the lowering in triglycerides is accompanied with small reduction in LDL and small increase in HDL).
127
What channels are blocked by amiodarone?
K+ channels
128
Describe the causative organism and progression of symptoms in syphilis.
Painless chancre (usually on the penis in men) but may also be in the vagina or rectum in women
Maculopapular rash, condyloma lata (genital warts), lymphadenopathy hair loss, muscle aches, sore throat
Subcutaneous granulomas, neurosyphilis (dementia, personality changes), tabes dorsalis (leading to loss of proprioception and vibratory sensation).
129
What would the bone marrow of someone with multiple myeloma look like?
Bone marrow plasma cells -\> overproduction of monoclonal IgG and destructive bone lesions -\> hypercalcemia.
130
What are the signs of a disseminated Neisseria meningitidis infection?
Hypotension, tachycardia, rapidly enlarging purpuring rash, DIC, coma.
131
What is the treatment for Wilson disease?
D-penicillamine (a chelating agent)
132
What metabolic defect would be associated with a child with long, thin extremities, generalized low muscle tone, developmental delay, a downward dislocation of the lens and thromboembolic events?
Homocystinuria caused by either cystathionine synthase or methionine synthase mutations.
133
How would you recognize a serratus anterior injury? What is the innervation of this muscle?
Winging of the scapula; the serratus anterior is innervated by C5,6 and 7 via the long thoracic nerve.
134
What is the biggest risk factor for placenta previa?
prior C-section
135
What form of thalassemia is incompatible with life and presents with hydrops fetalis and spontaneous abortion?
Alpha-thalassemia with deletions of all 4 alpha-globin genes: Hb Barts.
136
What symptoms are suggestive of turner syndrome? What congenital anomaly may be present?
Short stature, webbed neck and dactylitis ("sausage fingers"); may have coarctation of the aorta.
137
What findings would be seen on light microscopy in diabetic glomerulonephropathy?
Thickening of the the glomerular basement membrane and glomerulosclerosis (kimmelstiel-Wilson nodules)
138
What is the first-line treatment for seizure prophylaxis in patients with pre-eclampsia? What signs would indicate overdose for this drug?
Magnesium sulfate; loss of deep tendon reflexes (hyporeflexia) and CNS depression (drowsiness)˙.
139
What is the potter sequence? What is its cause?
Pulmonary hypoplasia
Oligohydramnios (cause)
Twisted face (retrognathia, flattened nose, low-set ears)
Twisted skin
Extremity defects
Renal failure (in utero)
140
What is the presentation on CXR of the most worrisome side-effect of bleomycin?
Ground glass opacities (pulmonary fibrosis).
141
What are the risk factors for nasopharyngeal carcinoma?
Male, asian (especial with epstein-barr virus infection), diet of salt-cured meats and fish.
142
Dislodged pieces of cartilage and subchondral bone would be found in what kind of arthritis?
Osteoarthritis
143
What disease process is indicated by the circled cells?
They are smudge cells (destroyed lymphocytes) suggestive of chronic lymphocytic leukemia or small lymphocytic leukemia (CLL/SLL) which originate from B lymphocytes.
144
What nerve root would be associated with decreased sensation around the inguinal ligament?
L1
145
What ovarian pathology would be present in a patient with Turner syndrome?
Follicular dysgenesis; theca and granulosa cells are replaced with fibrous tissue, resulting in "streak ovaries"
146
What is the clinical presentation and histology of the most common benign breast mass?
A fibroadenoma typically presents as a small, firm and mobile mass, nontender and changes with menstruation, with no skin changes, nipple discharge or lypmadenopathy.
On histology, fibrotic interlobular stroma are found around normal structure.
147
What breast pathology matches the picture?
Branching fibrovascular core exending into dilated duct: **intraductal papilloma**
148
What disease matches the histology?
Large cells with clear cells -\> Paget disease of the breast
149
What disease process matches the histology?
Parallel arrays of small, monomorphic cells infiltrating in lines: lobular carcinoma (in situ or infiltrative)
150
What disease matches the histology?
Pleomorphic sheets of cells invading adjacent fibroadipose tissue; invasive ductal carcinoma (the most common breast mass in older women.
151
What are psammoma bodies? What diseases are associated with them?
They are laminated concentric calcific spherules.
Associated with Papilary thoyroid carcinoma, Serous ovary, Meningioma and Mesothelioma.
152
What is the classification and typical clinical presentation for *Pasteurella multocida*?
It is a gram-neg coccobacillus, found commonly in cat/dog mouth.
Rapid and aggressive infection, skin abcess with pus.
153
Cat scratches in young children may be infected by this gram-negative rod.
*Bartonella henselae*.
154
Brucella canis, commonly found in dogs, can cause what kind of illness in humans? What are risk factors for infection?
B. canis is a gram-negative coccobacillus, can cause fever, malaise and hepatosplenomegaly but typically only immunocompromised & blood exposure would be at high risk for infection.
155
What is the mecahism of action by which trimethoprim leads to megaloblastic anemia?
TMP inhibits tetrahydrofolic acid formation -\> can also cause leukopenia and granulocytopenia.
156
What is the cause and presentation of DiGeorge Syndrome?
DiGeroge = thymus agenesis due to deletion in 22q11.2 (CATCH-22)
Cardiac defects
Abnormal facies
Thymic hypoplasia (opportunistic infections, think Candida and Pnumocystis)
Cleft palate
Hypocalcemia
157
What is the cause of absent tonsils and low B-cell concentrations?
X-linked agammaglobulinemia, caused by a recessive primary B-cell deficiency due to a mutation in Bruton's tyrosine kinase (impairing the maturation of B cells).
158
Which spinal tract controls voluntary movement?
Lateral cortitcospinal tract.
159
How would you differentiate multiple myeloma from Waldenstrom macroglobulinemia?
Multiple myeloma leads to high levels of IgG or IgA, Neoplastic proliferation of plasma cells (characteristic clock face). CRAB (hyperCalcemia, Renal insufficiency, Anemia, lytic Bone lesions).
Waldenstrom macroglobulinemia is characterized by excessive IgM. Proliferation of plasmacytoid lymphocytes, proteinurea, hyperviscocity syndrome, Bence Jones proteins (no lytic bone lesions).
160
What are the characteristics of the infective organism most likely associated with a tricuspid diastolic murmur in a person with IV drug use history?
Staphylococcus aureus is a catalase positive, coagulative positive cocci.
161
What are the characteristic findings on cardiac biopsy for a patient with rheumatoid fever?
Ashoff bodies with activated macrophages called Anitschkow cells.
162
Describe the characteristic cell in the lung biopsy. What is the diagnosis?
Reed-Sternberg cell; giant tumors cells mirror images. "owl eyes"). Hodgkin lymphoma.
163
What should be done prior to splenectomy in a setting of malignant invasion?
Vaccination against encapsulated organisms e.g. pneumococcus and Haemophilus influenzae.
164
Identify the organism
Plasmodium, because of malaria.
165
What is the classic presentation of leishmaniasis
Ulcers of the skin, mouth, and nose, fever, lymphadenopathy splenomegaly confirmed using biopsy and transmitted by infected sand flies.
166
What is the mechanism of action of isoniazid?
Inhibits the synthesis of mycolic acid to build the cell wall in mycobacteria
167
What is a common side effect of vincristine?
Peripheral neuropathy, areflexia
168
Identify the ovarian lesion.
Struma ovarii; teratoma containing thyroid tissue.
169
What is an early sign and cause of myotonic dystrophy?
Early signs: proximal muscle weakness. Cause: it is a nucleotide repeat expansion. Muscle biopsy shows atrophy of fibers.
170
What is the characterization of herpes viruses?
Double-stranded linear DNA
171
What drugs follow zero order elimination kinetics?
Phenytoin, ethanol, high dose aspirin
172
Which organs drain to the para aortic lymph nodes?
Testes, ovaries, kidneys, uterine fundus
173
How would you differentiate a gastric and a duodenal ulcer?
Gastric = worse with eating and associated with NSAID use. Must biopsy margins to r/o malignancy.
duodenal =Relief with eating. Associated with Zollinger-ellison syndrome. On histology, hyperplasia of Brunner glands.
Both strongly associated with H. pylori
174
What are the four mature defence mechanisms?
Sublimation, altruism, suppression, humour
175
How would you distinguish between a lesion of the upper trunk and lower trunk of the brachial plexus?
Upper trunk results in a waiters tip position due to deltoid, infraspinatus and biceps deficit (C5-C6)
lower trunk presents as a clawed hand or deficit hand muscles (C8-T1)
176
What is the pathogenesis of a complete classic mole?
An enucleated egg is fertilized by a single sperm, which then duplicates.
177
What disease process would explain symptoms of anemia with cola coloured urine in the morning?
Paroxysmal nocturnal hemoglobinuria. Caused by loss of PIGA gene required for GPI anchors for CD55 and CD59. Loss of CD55 and CD59 leads to complement-mediated hemolysis
178
Identify the pathology from the bone marrow aspirate. What are the defining features?
Hamophagocytic lymphohistiocytosis; macrophages are overactive leading to fever, pancytopenia, hepatosplenomegaly....macrophages are shown phagocytosing marrow cells.
179
How would you distinguish between cholecystitis, large bowel seeding and PID seeding of a liver abcess
Cholecystitis tends to present with fever N/V.
Large bowel ascending infection will often be accompanied by bloody diarrhea
PID will show lower abdo pain and adhesions of the peritoneum to the liver ("violin string")
180
What is the mechanism of action of ethosuximide
Ethosuximide is used for absence seizures and it blocks T-type calcium channels.
181
What hormone is secreted by dilated ventricles in heart failure? What are its physiologic effects (3)?
Brain Natriuretic Peptide (BNP), this acts on the collecting tubule to decrease Na+ reabsorption
Increases GFR by dilatation of afferent arteriole
Reduces the osmotic gradient by vasodilating the vasa recta.
182
Hyperintense lesions on FLAIR MRI may indicate what diagnosis?
MS
183
This kidney stone suggests infection with which microorganisms?
"staghorn stone" is made of ammonium magnesium phosphate, caused by infection by urease-producing bugs, eg. Proteus, Staph, Ureaplasma and Kliebsiella.
184
Which markers are Reed-Sternberg cells classically positive for?
CD15 and CD30
185
Describe the typical induction treatment for acute lymphoblastic leukemia
vincristine, L-asparaginase, prednisone
186
What chromosomal abnormality is associated with an increased risk of acute lymphoblastic leukemia?
Trisomy 21
187
Which organism causes a water diarrhea, hyponatremia and pneumonia with occasional CNS symptoms?
Legionella pneumophila
188
What is the mechanism of lead poisoning toxicity?
Inhibition of aminolevulinic acid dehydratase and ferrochelatase leading to issues in the heme synthesis pathway (hence, microcytic anemia).
189
What is the mechanism of action of steoroid suppression of inflammation?
Steroids inhibit NF-kB a transcription factor for TNF-alpha and other inflammatory agents.
190
An individual on albuterol which is experiencing persistent/chronic asthma should have what added to their treatment regiment?
An inhaled corticosteroid (fluticasone, budesonide).
191
How would you differentiate between injury to the common peroneal, the deep peroneal and the superficial peroneal nerve?
Deep peroneal: inability to dorsiflex foot, foot drop
Superficial peroneal, inability to evert foot and sensory loss over lateral leg and dorsal surface of foot.
Common peroneal = both.
192
Is furosemide a good choice for treatment of hypertension
No. It addresses volume overload, but generally has no effect on blood pressure.
193
What is the first line of treatment for diabetic nephropathy?
An ACE inhibitor -- it's renoprotective!
194
What is the presentation and cause of Prader-Willi syndrome?
Hyperphagia, obesity, intellectual disability, hypotonia and hypogonadism.
Occurs due to deletion or mutation of paternal copy of the gene on chromosome 15
195
What kind of antibody is rheumatoid factor? What is its epitope?
IgM; Fc portion of igG
196
Which receptors does ADH act on? What are their functions?
V1 increases blood pressure (vasoconstriction).
V2 lowers serum osmolarity (increases water reabsorption in collecting duct).
197
Suppose a patient is refusing a procedure and is capable of consent. What must you do before you grant the request?
Ensure they understand the risks and benefits of the procedures so their content is informed.
198
This patient presents with right flank pain. What is the diagnosis? What is the first line treatment?
Urolithiasis (kidney stones).
If hypercalciuric, then treat with hydrochlorothiazide
If gouty allopurinol would be ok.
199
What is procainamide's effect on the heart?
Procainamide blocks sodium and potassium channels, acting to slow depolarization in ventricular muscle fibres.
200
What is adenosine's effect on the heart?
Adenosine inhibits the SA AV and His-purkinje cell activity, decreasing conduction velocity by inhibiting L-type calcium channels.
201
What is the effect of verapamil in the heart?
Verapamil is a calcium channel blocker, lowers heart muscle contractility, highest specificity for heart.
202
How does HMG – CoA reductase activity affect cholesterol synthesis?
It is the rate limiting enzyme of cholesterol synthesis. Increases in activity result in higher cholesterol level
203
What is the mechanism of action of fibrates?
Activation of peroxisome proliferator activated receptor (PPAR) which increase HDL levels by increasing synthesis of the lipoprotein A1 and A2, as well as increasing lipoprotein lipase-mediate lipolysis.
204
What is the clinical presentation of Wilson disease?
Before age 40
Liver disease (hepatitis, liver failure, cirrhosis)
neurologic findings similar to Parkinson's
decreased serum ceruloplasmin
Kayser-Fleischer rings (brown discoloration of the cornea)
205
What is the most common cause of acute appendicitis in children?
Lymphoid hyperplasia, often subsequent to a viral infection or vaccination.
206
Which area of the brain has the highest concentration of dopamine receptors?
:Putamen
207
What would a nitroblue tetrazolium dye reduction test be helpful for diagnosing?
Chronic granulomatous disease (caused by lack of NADPH oxidase activity).
208
How does infection with clostridium tetani lead to muscle spasms?
The tetanospasmin is a exotoxin which cleaves SNARE proteins for inhibitory neurotransmitters including GABA and glycine which results in a net increase in muscle tone.
209
Which is the most common ligament torn in and ankle sprain due to overinversion or supination of the foot?
The anterior talofibular ligaments
210
What class of antidepressants can lead to a hypertensive crisis?
Monoamine oxidase inhibitors -\> tyramine injestion -\> norepinephrine release (but can't get degraded) ^^^BP
211
What type of skewness is this?
Negative skew
212
What type of skew is this?
Positive skew
213
A patient has a severe flush after starting IV antibiotic treatment. Which antibiotic was administered? How would you avoid this adverse effect?
Vancomycin. Do a slower infusion and/or add antihistamines.
214
What is the antibiotic most associated with aplastic anemia?
Chloramphenicol
215
What is the classification of the causative organism for lyme disease?
Borrelia burgdorferi; a corkscrew-shaped spirochete
216
What are the major acute regulators of inflammation (late phase response)?
IL-1, IL-6 and TNF-alpha
217
How do you differentiate between pre-renal vs intrinsic causes of kidney failure?
Pre-renal, Fractional sodium excretion \<= 1%; BUN:Cr \>= 20
Intrinsic; Fractional sodium excretion \> 2%; BUN:Cr \< 15
218
How do you calculate relative risk of developing a disease based on an exposure in a cohort study?
(odds of disease | exposure) / (odds of disease | not exposed)
219
What is the deficient enzyme that would result in elevated orotic acid? What is the inheritance pattern?
Ornithine transcarbamoylase; X-linked recessive.
220
A patient presents with hemibalismus on the right. Where is the lesion? What is the causative mechanism?
Left subthalamic nucleus (contralateral), often due to a lacunar stroke. The STN -\> globus pallidus, which fires inhibitory GABA neurons to the thalamus.
221
What changes to LH, FSH and estrogen in menopause?
LH and FSH go up, estrogen goes down.
222
Where do T cells develop in the lymph nodes?
The paracortex.
223
This patient presents with a history of joint and abdo pain as well as loose, greasy stools. Given the biopsy of the lamina propria below, what is the causative organism? What is the stain used on the micrograph?
Tropheryma whipplei (whipple dissease).
Per-iodic Schiff stain showing intracellular gram +ve bacteria.
Also can get cardiac and neurologic symptoms.
224
What is the treatment of carbon monoxide poisoning?
Intubate if require protected airway; otherwise hyperbaric oxygen.
225
What antidote can be given for cyanide poisoning?
Hydroxocobalamin
226
Why must alcohol be avoided in patients taking metronidazole?
Metronidazole inhibits acetaldehyde dehydrogenase, consumption of alcohol leads to buildup acetaldehyde which will produce nausea, vomiting, headache, palpitations, and flushing.
227
Differentiate cluster headaches from migraines.
Cluster headaches: periorbital, sharp pain non-pulsatile at the same time each day. Last up to two hours and presents with autonomic symptoms including nasal congestion, lacrimation, conjunctival injection, flushing, sweating. Treat with high flow oxygen, a triptan, verapamil.
Migraine headaches: unilateral location with throbbing and pulsatile pain lasting up to 72 hours. Often accompanied by auras, nausea and vomiting, photophobia and photophobia. Maybe in improved with NSAIDs, and ergotamine, selective serotonin agonists including sumatriptan.
228
Differentiate between familial adenomatous polyposis and Lynch syndrome (non-polyposis colorectal cancer).
FAP presents with thousands of polyps on colonoscopy and is due to mutations in the APC gene. Lynch syndrome is due to problems in mismatch repair leading to **microsatellite instability**. 70% of people develop colorectal cancer and there is a high risk of endometrial, ovarian, urinary tract, small intestinal, stomach, and biliary cancer.
229
A fracture to the femoral head could disrupt blood flow to which artery?
The medial femoral circumflex artery
230
What pathology is present on this image? which disease is associated with it?
Auer rods appearing in acute promyelocytic leukemia (a type of AML)
231
What pathology is present on the image?
Call-exner bodies or pseudo-rosettes are spaces which appear among the granulosa cells found in granulosa cell.(Ovarian) tumors.
232
What pathology is present on this image?
Cowdry A inclusion bodies - intranuclear eosinophilic inclusions with a clear halo found in VZV infections.
233
What vitamin deficiency is related to this image?
Keratomalacia associated with vitamin A deficiency may also present with edamatous and thickened cornea.
234
What is the classification of Helicobacter pylori?
A gram-negative, flagellated, curved bacteria
235
Which immunosuppressant is associated with renal toxicity?
Cyclophosphamide
236
What is the characteristic presentation of endometriosis
Endometrial tissue found outside of canal. Often in the ovaries, pelvis, or peritoneum during the menstrual phase, this tissue has outlet end will begin to accumulate for example with chocolate sis filled with reddish-brown blood in the ovaries. It is associated with cyclic and progressively worsening pelvic pain, bleeding, dysparenuia, dyschezia, and infertility
237
What is the typical presentation of juvenile idiopathic arthritis?
Relapsing spiking fevers accompanied by poly articular joints, swelling, and macular salmon pink rash present anywhere in the body. Sometimes generalized lymphadenopathy and hepatosplenomegaly.
Treatment is nSAIDs, steroids, methotrexate IVIG and biologics.
238
Stage of the cell cycle sites oocytes are suspended in from birth to ovulation?
Prophase I
239
Which human leukocyte antigens and for greater susceptibility to type I diabetes?
HLA DR4 and DR3
240
What are the characteristics of glioblastoma multiforme?
Most common brain cancer in adults, presents in the hemispheres with areas of necrosis and localized edema surrounded by pseudo palisading cells. Headaches, focal neurologic findings, nausea and vomiting are common.
241
What is the classic presentation for a posterior urethral injury?
Boggy, high riding prostate, blood at the urethral meatus, inability to insert a foley
242
What is the genetic cause of ocularcutaneous albinism?
A defect in tyrosinase which impairs the ability to convert tyrosine to melanin.
243
What is Waterhouse-Friderichsen Syndrome?
Primary adrenal failure due to Neisseria gonorrheae-caused adrenal hemorrhage. Presents with septicaemia, DIC and endotoxic shock
244
What is the common trigger for hemolytic uremic syndrome?
Enterohemorrhagic E. coli infection. It's also accompanied by diarrhea.
245
Which mutations are associated with autosomal dominant polycystic kidney disease? At what age does it typically present?
Polycystin 1 (Chromosome 16), less commonly polycystin 2 (chromosome 4)
Typical presentation is 20-30y
246
What are the classic symptoms of congenital rubella infection?
Sensorineural hearing loss, cataracts, cardiac disease (patent ductus arteriosus).
247
Which HLA antigen is associated with rheumatoid arthritis?
HLA – DR4
248
Which HLA antigen is associated with pernicious anemia and Hashimoto's thyroiditis?
HLA – DR5
249
Which diseases are associated with HLA – B27?
Ankylosing spondylitis, other seronegative arthropathy including psoriatic arthritis and reactive arthritis as well as inflammatory bowel disease and anterior uveitis.
250
What medication would you use to treat an exogenous ACTH-secreting tumor?
Ketoconazole or mitotane
251
What symptoms would you expect to see in goodpasture syndrome?
Hemoptysis and Hematuria
252
Thiamine (B1 deficiency) can result in what electrolyte imbalance?
Lactic acidosis
253
What metabolic disturbances would be expected in a patient being treated with furosemide?
Hypocalcemia, hypokalemia, hyponatremia, hypomagnesemia, metabolic alkalosis
254
How would you treat an acetylsalicylic acid overdose?
Stabilize ABCd, add sodium bicarbonate infusion.
255
What is the causitive organism for slapped cheek disease?
Parvovirus B19
256
What is the difference between brief psychotic disorder, schizophreniform disorder and schizophrenia?
Brief psychotic disorder \< 1mo
Schizophreniform disorder 1mo to 6 mo
Schizophrenia \>6mo
257
What organelle is prominent in plasma cells?
Rough ER
258
What type of cells are these? What condition are they typically found it?
Heart failure cells (these are hemosiderin-laden macrophages
259
What is mittelschmerz?
Unilateral ovarian pain on ovulation.
260
What are the risk factors for cervical cancer?
Early sexual activity, multiple partners, smoking, low SES
261
How would you treat hyperthyroid in the setting of pregnancy (or when radiation is contraindicated)
Propylthiouracil
262
Which enzyme is deficient in galactosemia?
Galactose-1-phosphate uridyltransferase
263
What is the reason why patients with SLE may have recurrent thrombosis?
Antiphospholipid antibody syndrome: antiphospholipid antibodies -\> bind and expose platelet phospholipids to clotting factors. Antibodies will cause a paradoxical increase in PTT (exogenous pathway).
264
What drugs can cause torsades de pointes?
Antiarrhythmics: Quinidine (IA, III antiarrhy9thmics)
Antibiotics
Anti"C"ychotics
Antidepressents
Antiemetics (ondansetron)
Predisposition in long QT
265
A patient undergoing treatment for cancer presents with new onset hyperglycemia. What is the most likely cause?
Prednisone
266
What type of murmur is heard in an Atrial Septal Defect?
ASD presents with a pulmonic systolic heart murmur with a wide fixed split S2
267
What type of murmur is heard in a patent ductus arteriosus?
PDA presents with a machinelike continuous murmur in the left infraclavicular lesion, often with tachy, dyspnea, poor growth.
268
What amino acid deficiency can lead to pellagra?
Tryptophan (hartnup disease)
269
What is globus sensation?
A psychological disorder in which a patient feels a lump in their throat; often follows a significant life stressor
270
Which medications are used to treat late-stage prostate cancer?
Leupromide — a GNRH analog (suppresses LH)
Flutamide — a nonsteroidal antiandrogen
Adjuvant radiotherapy in high-risk and metastatic disease.
271
How would you differentiate between asbestosis and coal workers' pneumoconiosis?
Coal miner's disease -\> look for "black, sooty lung"
272
What does this lung image show? Which disease is associated with it?
Ferruginous bodies (dumbbell like, rusty red), a sign of asbestosis
273
What anatastomosis is associated with esophageal varices?
Left gastric vein into the esophageal vein
274
How do you distinguish between someone who has been vaccinated vs someone who has been exposed to HepB
(+)anti-HBc indicates prior infection.
275
Hepatitis A and E are what kind of viruses?
Single-stranded, linear RNA viruses.
276
What is the cause that you would suspect in a child with Gower sign and calf pseudohypertrophy?
Duchenne Muscular Dystrophy (Gower = using arm to pull oneself up).
Often caused by frameshift mutation leading to deletion of one or more exons of the DMD gene.
277
How do you differentiate between HUS and DIC?
HUS = hemolytic anemia, acute kidney failure, thrombocytopenia *but no change to PT/INR or PTT*.
278
What type of medium is used to culture Bordatella pertussis?
Bordet-gengou or Regan-Lowe
279
What type of medium is used to culture Corynebacterium diptheriae
Lôffler medium
280
What grows on Thayer-Martin medium?
Neisseria gonorrhoeae
281
How would you culture Haemophilus influenzae?
Chocolate agar with factor V and X
282
What is the cause of medication-induced hemolytic anemia?
G6PD deficiency leading to sensitivity to oxidant drugs (e.g. antimalarials) or infections.
283
Which hair cells in the organ of corti are associated with higher pitched sounds?
Those at the proximal end (closest to the oval window)
284
What are the findings on EM / IF in poststreptococcal glomerulonephritis?
Dense humps on epithelial side of glomerular basement membrane (EM)
Granular pattern "lumpy bumpy" on IF
285
Which translocation is associated with burkitt lymphoma?
T(8;14) involving c-myc into immunoglobin heavy chain locus, leading to constitutive c-myc expression.
286
What effect on volumes does mannitol have?
Mannitol can be used to pull fluid into the intravascular space; it is used to treat increased ICP
287
What is the effect of triamterene?
It is a potassium-sparing diuretic used when spironolactone is not tolerated
288
What kidney pathology is shown in the image? What are the causes?
membranous nephropathy
Thickening of capillaries glomerular basement membrane on LF, spike and dome on EM.
Primary disease can be due to antibodies to phospholipase A2 (poor prognosis)
Secondary occurs with drugs, infections, SLE, solid tumors.
289
What kidney pathology is shown on the image?
Membranoproliferative glomerulonephritis
Mesangial proliferation, thickening of the basement membrane
May present with mixed nephritic / nephrotic signs.
Has low C3
290
What is the normal function of retinoblastoma protein?
prevents cell from progressing through G1/S checkpoint.
291
Where are melanocytes found?
In the basal layer of the epidermis.
292
What conditions involve defective Type IV collagen?
Goodpasture syndrome and Alport syndrome
293
What immune cells are found in the crypts of Lieberkuhn?
Paneth cells
294
What is the function of Chief cells?
Pepsinogen secretion.
295
What is the function of I cells?
Cholecystokinin release (stimulates secretion of pancreatic enzymes and HCO3)
296
What is the function of S cells?
Secretin (increases pancreatic and biliary HCO3 secretion)
297
What is the cause of megacolon and failure to pass meconium with bilious vomiting in a neonate?
Hirschsprung disease (failure of neural crest cell migration leading to missing Auerbach and Meissner plexuses)
298
What hormone is responsible for the development of male external genetalia in utero?
Dihydrotestosterone
299
Hexagonal crystals forming kidney stones are most indicative of what pathology?
Cystine reabsorption problem causing cystinuria.
300
Radiolucent stones with rhomboid crystals are indicative of what source?
Uric acid
301
What are the 3 types of radiopaque stones?
Calcium oxalate (dumbbell), Calcium phosphate (wedge-shaped). Think low-sodium diet and thiazides.
Ammonium magnesium phosphate (struvite, coffin-lid, think bugs).
302
A lactose fermentation test (MacConkey agar) would be most helpful for differentiating which bacteria?
Enterobacteriaceae:
Escherchia and Klebsiella ferment lactose
Salmonella and Shigella do not.
303
What are common causes of secondary hypertensive crises?
Anything that causes renal artery stenosis: atherosclerosis, fibromuscular dysplasia, CKD, hyperaldosteronism.
304
What congenital abnormality can occur in babies whose moms are undergoing lithium treatment?
Ebstein anomaly (tricuspid valve is lower into the RV, big RA, small RV).
305
What is the common presentation of leptospirosis & Weil disease?
Leptospira interrogans (from contaminated water) leads to flu-like symptoms, calf myalgia, jaundice and conjunctivial suffusion. Weil disease is the more severe form with renal failure and hepatitis.
306
How do you differentiate hemophilia A / B from hemophilia C?
Hemophilia A (factor VIII) and B (factor IX) may present with bleeding into deep soft tissues and hemarthrosis. Hemophilia C has less spontaneous bleeding (factor XI) and it is more common in Ashkenazi Jews, but still very rare. All show abnormal PTT but normal PT.
307
How does the botulinum toxin get into cells?
Retrograde transport along axonal microtubules via dynein.
308
What is orlistat used for?
Orlistat is used for weight loss in patients BMI \>30 (27 with comorbid conditions). It inhibits lipase -\> fat loss.
309
What is the abnormality? What causes it?
Horseshoe kidney due to fusion at the bases of the two kidneys. The inferior mesenteric artery stops the kidneys from rising to their normal level.
310
Describe the effects of angiotensin II on the afferent and efferent arterioles.
It vasoconstricts both, but the efferent arteriole *more*, so under low dosage they will increase GFR. At high doses, it decreases GFR by constricting both afferent and efferent arterioles the same.
311
How does total peripheral resistance change in a traumatic bleed?
TPR is increased as the body responds to a fall in blood pressure by vasoconstriction.
312
Differentiate coagulative from liquefactive necrosis
Coagulative (\*most organs\*) cell outlines present but absent nuclei
Liquefactive (lung, brain) release of enzymes degrades tissue producing a glob.
313
Which diseases are associated with Schistosoma?
S. haematobium -\> chronic inflammation of bladder
S. mansoni -\> intestinal schistosomiasis
314
Are cerebellar infarcts ipsilateral or contralateral to the lesion?
Ipsilateral defecit (double-crossover, once above the red nucleus and again below the red nucleus)
315
What is covered by medicare part A?
Hospital insurance, home hospice care + nursing homes
316
What is covered by medicare part B?
Basic medical bills (doctors offices, diagnostic testing)
317
What is covered by medicare part C?
Combo: A + B delivered by private companies
318
What is covered by medicare part D?
prescription Drugs
319
Fetal screening with an elevated level of alpha-fetoprotein is concerning for what congenital malformation?
Open neural tube defect (meningocele, myelomeningocele, encephalocele or anencephaly).
320
What changes on fetal screening raise suspicion of trisomy 18?
decreased alpha-fetoprotein, estriol AND beta-hCG
321
What changes on fetal screening are suspicious for trisomy 21?
Decreased alpha-fetoprotein and estriol
Increased inhibin A and beta-hCG
322
What diabetes medication can result in lactic acidosis?
Metformin.
323
What characteristics would you expect of the skin lesion with the following biopsy?
Fleshy-coloured pearly papules with central telangiectasia - a Basal Cell Carcinoma
324
Identify the organism on this gram stain.
Candida albicans
325
What symptoms can accompany Candida vulvovaginitis in immunocompromised patients?
Esophagitis
326
How would you clinically differentiate between gonorrhea and candidiasis in a patient presenting with white discharge in the vaginal canal?
Gonorrhea presents with urethritis and PID.
327
Name the 3 branches of the aortic arch, in order from the heart.
1. R brachiocephalic trunk (branching to R common carotid, R subclav and thyroid ima)
2. L common carotid
3. L subclavian
328
What is lambert-eaton syndrome?
A paraneoplastic syndrome in which antibodies are generated against presynaptic calcium channels at the neuromuscular junction.
Symptoms include proximal muscle weakness, decreased reflexes, sometimes diplopia
329
What changes do you expect to serum calcium, phosphorus and alkaline phosphatase in the setting of a patient with osteoporosis?
All will be normal.
330
What percentage of RB mutations are spontaneous?
55% of cases involve two spontaneous mutations
In the other 40%, kids inherit one allele which is mutated and develop a spontaneous mutation.
331
An individual reports a growing mass exuding a yellow discharge one month post oral surgery. What is the causative organism based on this acid-fast stain?
Actinomyces israeli, a branching rod-like gram-positive obligate anaerobe.
Characteristic sulfur granules, negative on acid-fast stain.
Treat with penicillin G
332
What is the mechanism of action of sulfonamides?
Block bacterial nucleotide synthesis
333
What is the mechanism of action of penicillin G (IV/IM) or V (oral)?
Inhibits transpeptidase cross-linking and prevents cell wall synthesis.
334
What is the mecahism of action of amphotericin B?
Binds ergosterol, forms pores in the membrane
335
What is the mechanism of action of azoles?
Inhibits ergosterol synthesis (fungal infections!).
336
What markers are found on T helper cells?
CD4, CD40L, CXCR4/CCR5 (co-receptors for HIV)
337
CD5 is found on what cells?
most T cells (and also CLL cells)
338
What markers do NK cells have?
CD16 and CD56
339
What marker is found on cytotoxic T cells?
CD8
340
What markers are found on B cells?
CD19, CD20 and CD21
CD40
MHC II
Ig (binds antigen)
341
What are these findings suggestive of in the context of fever and new heart murmur? What is the most common causative organism?
These are roth spots, osler nodes janeway lesions and nail-bed hemorrhage, suggestive of bacterial endocarditis.
Acute onset tends to be Staph aureus
Subacute is viridans streptococci (tends to be associated with dental work)
342
What is the classification of vvridans streptococci?
Gram-positive Cocci
Catalase-negative
alpha-hemolytic
opthrocin resistant
343
identify the brain tumor
oligodendroglioma: Fried egg with interspersed "chicken-wire" capillaries
344
A sudden swollen, warm exquisitely tender big toe is a classic presentation of...
gout
345
What is the presentation of neuroleptic malignant syndrome? What is the best management?
Fever, muscle rigidity, myoglobinuria, altered mental status.
Start benzodiazepines, then dantrolene (skeletal muscle relaxant) or bromocriptine
346
If the hip drops to the left (Tredelenburg), which side is weak?
The right gluteals; could be due to damage to the superior gluteal nerve (nerve roots L4-S1)
347
What is this finding on RBC smear called? Which disease process does it suggest?
Rouleaux formation, Multiple myeloma
348
What is the mechanism of action for the antibiotic commonly used to treat C. diff and MRSA?
Vancomycin is used for gram-positive infections; it binds D-ala-D-ala and prevents cell wall synthesis.
349
The following lesion appears on a patient with HIV. What is the cause of the lesion and the most common accompanying symptoms?
Kaposi sarcoma (a malignant proliferation of epithelial cells caused by HHV-8 infection).
Can be accompanied by mucosal bleeding leading to hematochezia, hematemesis or melena.
350
What conditions are associated with von Hippel-Lindau syndrome? Which chromosome is it located on?
chromosome 3p25
hemangioblastoma of the cerebellum, retinal capillary and spinal cord, polycythemia, renal cell carcinoma and pheochromocytoma.
351
In a fetus at risk of pre-term birth, what are steroids used for?
To increase fetal lung compliance (promotes synsthesis of surfactant by maturation of type II pneumocytes)
352
What is the presentation of 21-hydroxylase deficiency?
Congenital adrenal hyperplasia, salt-wasting hypotension (no aldosterone and cortisol) with shunting towards sex hormones.
353
What is the cause of the following tumor? In which ages does it present?
This is a Wilms tumor, common in young children between 2-4 years old. They arise from neoplastic embryonic renal cells -\> abnormal proliferation of metanephric blastema (nephrogenic rests).
Can be associated with WAGR syndrome with WT1 mutation on chromosome 11.
354
What is WAGR syndrome?
Wilms tumor
Aniridia
Genitourinary abnormalities
mental Retardation
355
What is the indication and mechanism of action of prochlorperazine?
It is used as an antipsychotic agent and also potent antiemetic as an adjunct to chemo.
Acts by blocking D2 receptors in the chemotrigger receptor zone, located in the area postrema in the medulla.
356
How do you calculate sensitivity?
TP / (TP + FN)
357
How do you calculate specificity?
TN / (TN + FP)
358
What is the virulence factor that contributes to sepsis in Neisseria meningitidis?
Lipooligosaccharide (stimulates inflammatory cytokines similarly to LPS)
359
HIV encephalopathy occurs due to infection of what cells in the brain?
macrophages and microglia.
360
What is the critical period of fetal development for teratogen exposure?
weeks 3-8
361
What are common manifestations of uncal herniations?
Ipsilateral CN III compression (fixed dilated pupil, "down and out" eyeball, ptosis)
Contralateral hemiplagia (or ipsilateral if compression hits the structures on the other side of the brain)
Impaired consciousness.
362
Identify the thyroid carcinoma. What are the key characteristics?
Papillary thyroid carcinoma. Commonly presents with asymptomatic cold nodule after previous radiation exposure.
Large overlapping nuclei with finely dispersed chromatin; often optically clear.
363
What cells are characteristic of anaplastic thyroid cancer?
Large osteoclast-like multinucleated giant cells and biphasic spindle cells amongst sheets of undifferentiated pleomorphic cells.
364
What is panacinar emphysema?
Alpha-1 antitrypsin deficiency leads to chronic and progressive dyspnia and liver failure
365
How does CF affect the gut?
accumulation of pancreatic enzymes in the pancreas -\> pancreatitis
Nutrient malabsorption due to dessication -\> weight loss, potential obstruction
Biliary secretions are impaired -\> biliary cirrhosis.
366
Describe the effects of tamoxifen
It is a selective estrogen receptor modulator
estrogen antagonist in breast
estrogen agonist in bone (inhibits osteoclasts) and uterus (increases risk of endometrial carcinoma)
367
What is an important side effect of heparin?
heparin induced thrombocytopenia (a type II reaction) due to antibodies against heparin/platelet factor 4 complex.
Occurs with a drop of 50%+ platelets in 3-10 days following treatment. More common with previous exposure to heparin.
368
Which symptoms make a diagnosis of henoch-schônlein purpura more likely vs granulomatosis with polyangiitis?
HSP -\> arthralgia and abdo pain
GPA -\> upper and lower resp findings, nephritic syndrome
369
What is the mechanism of action of metronidazole?
Forms free-radical metabolites that damage bacterial or protozoan DNA
370
Galactorrhea, abdo pain relieved by eating and hypercalcemia raises suspicion for which syndrome?
Multiple endocrine neoplasia type 1 (pituitary prolactinoma, zollinger-ellison syndrome caused by gastrinoma, parathyroid neoplasm).
371
A beta antagonist would have what effect on cAMP?
Decreased cAMP (because normally beta receptors are Gs -\> increased cAMP).
372
How would you distinguish between hypercalcemia caused by parathyroid neoplasm and a lytic bone disease (e.g. multiple myeloma)
Alkaline phosphatase levels should be elevated in PTH neoplasm
Multiple myeloma is often accompanied by proteinuria (due to excessive antibody production).
373
What is the clinical presentation of invasive ductal carcinoma?
Mass with sharp margins with dimpling on the skin. Biopsy shows small glandular cells with a stellate appearance.
374
What is the clinical presentation of Paget's disease.
Eczematous patches on nipple.
375
What chromosomal abnormality is associated with Hirschsprung disease?
Down syndrome
376
What is the motor and sensory distribution of the musculocutaneous nerve? Which nerve roots does it originate from?
Motor: coracobrachialis, biceps, brachialis
Sensory: lateral part of the forearm
Roots: C5-C7
377
Which cells are involved in acute graph rejection?
Activation of cytotoxic T-cells (CD8)
378
How do you treat achalasia?
Use calcium channel blockers e.g. nifedipine or nitroglycerin to have smooth muscle relaxation.
Botulinum toxin can be used as well.
Surgery is another option.
379
What are the 2 possible diagnoses for the abnormality on blood smear?
What finding would you see on labs?
These are spherocytes
Hereditary spherocytosis or autoimmune hemolytic anemia.
Increased mean cell hemoglobin concentration (MCHC)
380
What is trichotillomania?
Compulsive hair-pulling resulting in hair loss. Often precipitated by tension.
381
What is alopecia areata?
An autoimmune hair loss disorder. No inflammation, no scarring, no itching painless hair loss, often accompanied by nail pitting
382
Describe the differences between CIN 1, 2 and 3
Cin 1 -\> low-grade intraepithelial neoplasia \< 1/3 of epithelium
CIN 2 -\> between 1/3 and 2/3
CIN 3 -\> between 2/3 and full thickness.
Invasion beyond the epithelium = invasive cervical carcinoma
383
A patient presents with frequent resp infections, broductive cough with pus and bloody sputum, rales and ronchi on auscultation. What is the diagnosis?
Bronchiectasis (thickening of the bronchial walls due to inflammation/infection)
384
What are these bodies called? What is the diagnosis?
Hentz bodies, G6PD deficiency
385
What is the fracture? Which nerve is most likely impacted?
Supracondylar fracture of the humerus -\> median nerve.
386
Which fracture would typically be associated with a radial nerve injury?
Midshaft fracture of humerus, compression of the axilla.
387
Which fracture would present as an ulnar nerve injury?
Fracture of the medial epicondyle of the humerus
388
How would you distinguish between a radial, ulnar and median nerve injury?
Rardial nerve -\> wrist drop, loss of grip strength, loss of sensation over posterior arm and forearm
Ulnar -\> loss of wrist flexion, flexion of medial fingers, abduction and adduction of fingers, loss of sensation over little finger and half of ring finger as well as hypothenar eminence.
Median -\> loss of grip strength, decreased sensation over thumb and lateral 3 fingers.
389
Which translocation is associated with follicular lymphoma? What are the clinical and histological signs?
t(14;18) -\> bcl-2
Recapitulates lymph node architecture.
Presents as waxing and waning painless peripheral adenopathy, splenomegaly and B symptoms.
390
Differentiate between somatic symptom disorder and conversion disorder
Conversion disorder mimics voluntary motor or sensory system disease, but patients typically have a lack of concern about symptoms
Somatic symptom disorder is significant distress or impairment due to one or more somatic symptoms
391
What is a systemic strategy for improving patient sign-outs, CAUTI and ventilator-associated pneumonia?
Implementing a checklist!
392
What are the most common causes of aortic stenosis?
\< 60y.o, US -\> bicuspid aortic valve
Developing countries -\> rhematic heart disease (often presents with mitral defects)
393
What is the presentation of a tumor that stains positive for S100 protein at the cerebellopontine angle?
This is an acoustic neuroma (a schwannoma).
Presentation: hearing loss, dizziness, and impaired balance.
394
Bilateral acoustic neuroma is pathognomonic for...?
Neurofibromatosis type 2.
395
What medication would you use to address torticolis subsequent to haloperidol?
Benztropine (an anticholinergic agent).
396
What disorder is associated with type I collagen defect?
Osteogenesis imperfecta: blue sclerae, tooth abnormalities, multiple fractures and hearing loss.
397
What disorders is associated with type II collagen defects?
Kniest dysplasia (short stature)
Stickler syndrome (hereditary ophalmoarthropathy, deafness)
398
What disorder is associated with type III collagen?
Ehlers-Danlos syndrome (EDS), vascular type. Aneurysmal, organ rupture, milder skin/joint issues.
399
Which disorder is associated with type IV collagen?
Alport syndrome (X-linked dominant inheritance)
Eye problems, glomerulonephritis, sensorineural deafness.
400
What is metoclopramide used for?
A prokinetic agent for GI motility (blocks D2 receptors). Is also useful as an antiemetic (D2 CNS receptors).
Parkinsonian symptoms can result as side-effects.
401
What is bethanechol used for?
Gastric prokinetic agent -\> cholinergic side-effects.
402
What is scopolamine used for?
Anticholinergic used for nausea.
403
What is the most common cause of death for patients \>65 years old
Heart disease
404
What is the only treatment for familial adenomatous polyposis?
Full colonic resection.
405
What are the physiological effects of beta-blockers on the heart?
Reduced sympathetic tone -\> lower HR
Lower HR -\> increased duration of diastole and increased coronary filling.
Decreased contractility, cardiac output, HR, and vasoconstriction.
406
What is the classic presentation of Marfan syndrome?
Dislocated lens, tall stature, scoliosis, aortic involvement (aortic regurg)
407
A positive hydrogen breath test with an increased stool osmotic gap in the setting of normal-appearing villi and abdo pain, diarrhea, flatulence would raise suspicion for what condition?
Lactose intolerance
408
What does this ECG show?
Wolf-Parkinson-White syndrome.
Key findings are short PR, long/wide QRS, upsloping early QRS, commonly presenting with AVRT.
Due to an accessory tract bypassing the AV node
409
This individual has a creatininne of 1 mg/dL. What is the most likely diagnosis?
increased PTH
410
A "blowing" holosystolic murmur would suggest what kind of pathology in a 4-year-old?
Ventricular septal defect.
411
What is the second-line therapy for high cholesterol?
Niacin -\> significantly elevated HDL, reduced hepatic triglyceride and VLDL synthesis.
Side effects: flushing.
412
How would you differentiate between von Willebrand disease and hemophilia A and B?
vWD typically presents with epistaxis, menorrhagia, prolonged bleeding after procedure (primary hemostasis).
Hemophilia A and B is going to present appropriate hemostasis during procedure but secondary hemorrhage into joints and muscle compartments.
Reduced ristocetin-induced platelet activation is specific and sensitive for vWF
413
What is asherman syndrome?
Secondary amenorrhea due to scarring of the endometrial layer of the uterine cavity
414
What is Kallmann syndrome?
Congential hypogonadotropic hypogonadism due to failure of migration of GnRH-producing neurons.
415
How would you address a patient that has deficiency of interleukin-12?
Treat with interferon-gamma, which supports Th1 differentiation.
416
What is the unhappy triad of knee injury?
ACL injury, damage to medial meniscus and MCL (positive McMurray to valgus pressure).
417
What is the anatomic location of a direct inguinal hernia?
Medial to the inferior epigastric vessels, lateral to the rectus abdominis and superior to the inguinal ligament
418
What is the anatomical location of an indirect inguinal hernia
Lateral to the inferior epigastric artery and superior to the inguinal ligament
419
What is the most common cause of subarachnoid hemorrhage?
Ruptured arterial aneurysm.
420
What are the structures labeled A-E? What is their relevance for parkinson disease?
A = globus pallidus. Surgical ablation of the internal segment reduces inhibitory tone to the thalamus, improving bradykinesia
B = Putamen
C = Internal capsule (transmission of motor signals from cortex to body)
D = Caudate nucleus
E = Corpus callosum
421
What is the most common cause of cholelithiasis?
Increased cholesterol secretion in bile leading to cholesterol stones.
422
How would you distinguish between cholecystitis and biliary colic?
Chole -\> fever, **persistent** abdo pain, murphy's
Biliary colic -\> **intermittent** abdo pain radiating to back, worse after meals.
423
Which malignancies are associated with asbestosis? What distinguishes them?
Bronchogenic carcinoma -\> multiplicative effect with smoking, presents with hemoptysis
Mesothelioma -\> not associated with smoking, presents 30-40y after exposure with pleuritic chest pain and SoB.
424
What is the most common cause of acute MI?
Plaque rupture with background atherosclerosis.
425
How would you distinguish between Scurvy and Vitamin K deficiency?
Vitamin K deficiency -\> bleeding subsequent to broad spectrum antibiotics or in neonates
Vitamin C / Scruvy -\> bleeding subsequent to malnutrition, with swollen gums, bruising petichiae, corkscrew hair.
426
What is the inheritance pattern of von Hippel-Lindau disease?
Autosomal dominant.
427
What is a sentinel event? What must be done in response?
Sentinel event = an unexpected occurance involving death or serious injury
Must do a root cause analysis.
428
What is failure mode and effect analysis?
Attempting to identify the most likely or risky points of failure in a system in order to mitigate them.
429
What is the venous drainage of internal and external hemorrhoids?
Internal hemorrhoids -\> painless, drains to superior rectal vein
External hemorrhoids -\> painful, drains to inferior rectal vein to IVC.
430
How does shigella infect the host?
Invades M cells in peyer patches.
431
What is a courvoisier sign? Which disease is most likely?
Courvoisier = palpable gallbladder.
Pancreatic cancer (often also presents with painless jaundice, new-onset diabetes mellitus as the neoplasm blocks the bile ducts and pancreatic ducts).
432
What is the most likely consequence of an untreated hydratiform mole?
Choriocarcinoma
433
How does rabies infect the CNS?
Direct infection and retrograde axonal transport.
434
How do you distinguish between legionella pneumonia and tuberculosis?
Leogionella -\> thrombocytopeneia, elevated creatinine and BUN suggestive of kidney involvement as well as abdo pain.
Tuberculosis -\> chronic cough, fever, night sweats and weight loss.
435
What is the first-line treatment of HTN in pregnancy? What must be co-administered with it?
Hydralazine
A beta blocker (e.g. labetalol) to counter tachycardia
436
What effects are linked to amiodarone?
Hypo/hyperthyroid, pulmonary fibrosis, blue-gray skin deposits, photodermatitis, neurologic effects, constipation, HF, heart block, bradycardia.
437
Differentiate between Wilson disease and hereditary hemochromatosis.
Wilson -\> copper accumulates in the liver (cirrhosis), brain (parkinson-like, hemibalismus, dementia), cornea (Kayser-Fleischer rings). Caused by a ceruloplasmin mutation.
Hemochromatosis: Bronze diabetes, decreased libido/ED. Micronodular cirrhosis. Caused by AR HFE gene mutation, leading to excessive iron absorption.
438
Differentiate between CF and Kartagener syndrome
Kartagener -\> situs inversus, no ileus (ciliary dysmotility)
439
In addition to strawberry tongue, what are the other symptoms of Kawasaki disease?
High fever, cracked lips, conjunctivitis.
440
What is a dangerous complication that can result from Kawasaki disease?
Coronary aneurysm and MI
441
What is tumor lysis syndrome? How is it treated?
hyperkalemia, hyperuricemia and hyperphosphatemia with secondary hypercalcemia secondary to chemotherapy.
Treat with allopurinol to reduce uric acid production.
442
What is the mechanism of action of the 1st-line treatment for asthma exacerbation?
1st line treatment is a B2 receptor agonist, leading to Gs activation of PKA and block of MLCK.
B2 = 2 lungs
443
How do you treat hereditary spherocytosis?
Splenectomy
444
What are the saliient features of this liver biopsy? What is the diagnosis?
Hypercellularity, hygh nuclear-to-cytoplasm ratio, pleomorphism. May be accompanied by bruit
Hepatocellular carcinoma.
445
What is a hemangioma?
A benign tumor (most common noncancerous liver tumor), liver bruit can be heard, but B syptoms and malignant hepatocytes not found.
446
How does tissue plasminogen activator (tPA) and other clotbusters work?
Convert plasminogen to plasmin, leading to cleavage of thrombin and fibrin clots.
447
How does heparin work?
Heparin activates antithrombin III, which inactivates Xa and thrombin.
448
How do clopidogrel and ticlodipine work?
They inhibit the binding of fibrinogen to platlets, blocking further clot formation.
449
What is I-cell disease? What is the cause?
AKA mucolipidosis II or inclusion cell disease. Presents with joint contractures and umbilical/inguinal hernia. Due to deficiency of N-acetylglucosamine-1-phosphotransferase leading to inability to correctly tag enzymes for direction to lysosomes via mannose-6-phosphate attachment.
450
What are the symptoms of the 4 major dopaminergic pathways and their relationship to schizophrenia?
Mesocortical -\> decreased activity = negative symptoms
Mesolimbic -\> increased activity = positive symptoms (hallucination)
Nigostraiatal -\> decreased activity = dystonia, tarditive dyskinessia, parkinsonism
Tuberoinfundibular -\> decreased activity = increased prolactin and sexual dysfunction.
451
What is the best management for somatic symptom disorder?
Continued follow-up with the same provider. Reduces unnecessary testing and fragmentation of care.
452
What are germ tube-negative fungi?
Histoplasmosis, blastomycosis, coccidiomycosis with some candidia.
453
What are germ tube-positive fungi?
Candida albicans
454
What brain tumors have foamy cells and high vascularity?
Hemangioblastoma -\> not usually found in the cerebellar midline.
455
Name the brain tumor. What are the characteristic findings?
Medulloblastoma: small blue cells around a neuropil (homer-wright rosette). They are the most common cerebellar midline tumor in children and can cause hydrocephalus and present with truncal ataxia and gait disturbances.
456
How do you distinguish between autoimmune hemolytic anemia, MAHA and PNH?
Autoimmune hemolytic anemia = direct Coombs test, increased LDH, increased bilirubin, decreased haptoglobin.
MAHA = negative direct Coombs, presents with fatigue anemia and thrombocytopenia. Concomitant small-vessel occlusion pathology.
PNH = negative direct Coombs, morning hematuria.
457
What HLA is associated with T1DM?
HLA-DR3
458
What HLAs are assocaiated with hemochromatosis?
HLA-A3
459
What HLAs are associated with celiac disease?
HLA-DQ2
460
What diseases are associated with HLA-DR2
MS, hay fever, SLE, goodpasture syndrome.
461
What is the most common side-effect of ethambutol?
Bilateral optiic neuritis.
462
What is the presentation of CREST? What autoantibodies are associated?
Calcinosis
Raynaud
Esophageal dysfunction
Sclerodactyly
Telangiectasias,
Caused by anticentromere antibodies.
463
What is the first-line treatment for chemotherapy-associated nausea? How does it work?
Odansetron, a 5-HT3 receptor antagonist.
464
How would you diagnose gallstone ileus?
Air in the biliary tree, bowel obstruction, cholelithiasis without cholecystitis, bilious vomiting.
Caused by a large gallstone that goes through a fistula between gallbladder and SI and then blocks the ileocecal valve.
465
What are the three blood vessels contained in the umbilical cord?
2 umbilic arteries (returning deoxygenated blood from fetus)
1 umbilical vein carrying oxygenated blood from the placenta
466
What is suggestive of uremic platelet dysfunction? What is the impact on PT PTT and platelets?
Prolonged mucosal bleeding and bruising, elevated blood urea nitrogen and chronic kidney disease are hallmarks of uremic platelet dysfunction.
PT, PTT, and platelets will be normal as nitric oxide interferes with platelet adhesion and aggregation as well as platelet endothelium interaction.
467
What is the mechanism by which bacillus anthracis causes cell necrosis?
Anthrax has edema factor and lethal factor. EF increases cAMP, LF removes the n-term from MAPKK.
468
Which organisms are associated with painless sores?
Syphilis and anthrax.
469
What is the mechanism of cholera toxin?
Constitutional activation of the GS subunit leading to increased cAMP and increase chloride secretion into gut following with water.
470
Which virus is associated with increased risk of Hodgkin's lymphoma?
EBV
471
What medication can be given in an MI to relieve pain? What is the mechanism?
Nitroglycerin for angina; produces venous dilation and decreased preload, ultimately reducing myocardial O2 concentration.
472
Which bacteria most commonly causes urinary tract infections in individuals with a Foley catheter, specifically with the presentation of aortic valve endocarditis?
Enterococcus faecalis (gram +ve, negative nitrite on urinalysis)
473
What is the mechanism of action of Spironolactone?
It is a competitive inhibitor of aldosterone binding.
474
Which 2 tumor markers are associated with a presentation of constitutional symptoms, jaundice and hepatomegaly along with elevated amylase, lipase, and alkaline phosphatase?
Pancreatic cancer, specifically CA19-9 and cardioembryonic antigen (CEA)
475
What does this x-ray show? What additional findings are associated with this condition?
Congenital diaphragmatic hernia.
Typical findings on exam include scaphoid abdomen and barrel chest
Also presents with pulmonary hypoplasia and pulmonary hypertension (pulmonary artery pressure \>22mmHg)
476
What is hantavirus cardiopulmonary syndrome? What would you see on exam, CXR and investigations? What is the natural reservoir for the causative organism?
O/e: Fever, myalgia, cough, headache, N/V
CXR: Pulmonary edema (bilateral lung infiltrates and pleural effusions)
Labs: Leukocytosis, thrombocytopenia, elevated liver enzymes
Hantavirus tranmission occurs via rodent contact (e.g. deer mice feces).
477
What is the window to give tPA for stroke?
3.5-4hrs after first onset of symptoms
478
How do you reverse tPA? How does this agent work?
Aminocaproic acid (blocks conversion of plasminogen to plasmin).
479
What cardiac tumor is associated with tuberrous sclerosis?
Rhabdomyoma (typically on an atrial or ventricular wall).
480
Which GPCR act via the Gq pathway (phospholipase C -\> PKC -\> smooth muscle contraction)?
HAVe 1
M1 & M3
481
Which GPCRs act via the Gs pathway (Stimulation of adenylate cyclase)?
all the Bs (B1, B2 and B3), D1, H2, V2
482
Which GPCR act via the Gi pathway (inhibition of adenylate cyclase)
2 MAD
483
Identify the atria and ventricles on this echo
A -\> RV
B -\> LV
C -\> LA
D -\> RA
E-\> cardiac apex
484
Name other thiazide diuretics than hydrochlorothiazide
Chlorthalidone, indapamide, metolazone
485
What is the classic presentation of somatostatinoma? Which pancreatic cells normally produce this hormone?
Somatostatinoma -\> tumor secreting somatostatin. Classic presentation is steatorrhea, diabetes melllitus, gallstones. Labs will show decreased amylase, lipase, insulin, pepsio.ngen and glucagon.
Somatostatin is normally secreted by D cells in the pancreas.
486
What is the first step in management of a patient with obstructive sleep apnea?
Polysomnography.
487
What is a common complication of ulcerative colitis?
Primary sclerosing cholangitis (note that most folks with PSC develop UC, but not necessarily the other way around)
488
Describe rhabdomyolysis. What drugs are associated with it?
Classic triad: myalgias, generalized weakness, myoglobinuria -\> ATN.
Statin-induced
489
What is the diagnosis in this pre-term neonate with dyspnea and cyanosis? How would you differentiate between the common syndromes which lead to neonatal respiratory distress?
Atelectasis with air bronchograms and *low* lung volumes = NRDS
TTN would present with pulmonary edema with *increased* lung volumes and pleural effusion.
490
What are characteristic symptoms and ECG presentation for hyperkalemia?
Ascending flaccid muscle paralysis.
ECG shows peaked T waves in a wide QRS with sinus bradycardia.
491
What is the ACLS algorithm for the treatment of ventricular fibrillation?
1. Defibrillation
2. Epinephrine
3. Amiodarone
492
What is the first-line treatment for community acquired pneumonia?
Doxycyclin or a macrolide (erythromycin, clarithromycin, azithromycin).
493
Which antibiotics can interact with statins?
Macrolides (erythromycin, clarithromycin, azithromycin) inhibit cytochrome P450 which increases statin concentrations.
494
What is monoclonal gammopathy of undetermined significance? How is it managed?
Elevated serum protein with \<3g/dL of M protein in an otherwise asymptomatic individual.
Management is follow-up retesting in 6 mos to rule out progression to multiple myeloma.
495
How would you landmark the placement of a central line within the internal jugular vein
Lateral to the common carotid artery
496
What symptoms are concerning for Zollinger-Ellison syndrome?
Gastric ulcers that are refractory to PPIs and distal to the duodenal bulb = elevated gastrin, due to hypersecretion secondary to neoplasm.
497
What hematologic findings occur in the context of COPD?
Hypoxemia -\> EPO release -\> erythrocytosis (polycythemia)
498
What drugs can intefere with absorption of fluoroquinolones?
Calcium carbonate (in general, polyvalent cations including Ca2+, Mg2+ or Fe2+)
499
Name the arterial derivatives of the aortic arches (1-4, 6)
1. maxillary artery
2. stapedial and hyoid
3. common carotid and proximal internal carotid
4. L -\> aortic arch R -\> R subclavian
5. --
6. Proximal pulmonary and ductus arteriosus.
500
What pathology is suggested by this murmur?
Mitral regurgitation
501
What is the best treatment for a child who has a positive cellophane tape test and nighttime perianal itching?
Albendazole, mebendazole or pyrantel pamoate (contraindicated in pregnancy) for the treatment of pinworm.
Must treat the family & counsel washing all the bed linens.
502
What combination of drugs is used in highly active antiretroviral therapy for HIV?
Dolutegravir, tenofovir and emtricabine
503
What is ganciclovir used for?
Treatment of cytomegalovirus and other herpes viruses.
504
How would you differentiate between chronic hepatitis B and hepatitis C infection?
Hepatitis B tends to present with membranous glomerulopathy and arthralgias.
505
What is the first-line treatment for chronic hepatitis B infection?
Lifelong treatment with tenofovir.
Side effects can include renal insufficiency and decreased bone density.
506
What is a typical regimen for chronic hepatitis C with accompanying renal disease?
Glecaprevir and pibrentasvir
507
What are the characteristics of the most common causative organism for bacterial pharyngitis?
What are the autoimmune complications which may follow infection?
Streptococcus pyogenes is a gram-positive, beta-hemolytic coccus growing in chains. It produces M protein which inhibits phagocytosis and mimics human cellular protein epitotpes.
Autoimmune sequelae include rheumatic fever and glomerulonephritis.
508
Development of an air embolism shortly after removal of a central venous catheter represents what kind of medical event?
A "never event" or serious reportable event.
509
What kinds of kidney stones are produced in patients with Crohn's?
Calcium oxalate stones (due to increased lipids in gut complexing with calcium, causing an oxalate imbalance).
510
What is the formula to calculate clearance of a drug?
511
Name the type IV hypersensitivity reactions
T-cell mediated: TB tests, contact dermatitis (touch), erythema nodosum (TB & more), hashimoto Thyroiditis and MS.
512
How are slow waves in the GI tract generated?
They are caused by the interstitial cells of Cajal, independent of stimuli. They are the basal rhythm of the gut and are different for each organ.
513
What is the eventual consequence of all progressive CKD? What would you expect to see on labs?
Secondary hyperparathyroidism: hypocalcemia, hyperphosphatemia, high PTH, and high alkaline phosphatase.
514
What is a common kidney sequellae of rhabdomyolysis?
Acute tubular necrosis
515
What is the diagnosis? What is the cause of this disease? What other findings would you expect?
Niemann-Pick
This cherry-red spot would be accompanied by hepatosplenomegaly, neurodegeneration and foamy macrophages with lots of lipid.
This is caused by a sphingomyelinase deficiency (problem converting sphingomyelin to ceramide)
516
What is the characteristic presentation of Crohn's disease? What type of inflammation is associated?
Abdo pain, diarrhea, fatigue, weight loss, apthrous ulcers in the mouth with fecal occult blood.
Transmural inflammation (vs mucosal/submucosal in UC) is characteristic.
517
What is the mechanism for acute respiratory distress syndrome? How it diagnosed?
Mechanism: cytokine release (IL-1) stimulates increased cap permeability leading to loss of surfactant, bilateral consolidations, resp failure and PaO2/FiO2 \< 300.
518
What is the presentation of 17a-hydroxylase deficiency?
Inability to produce glucocorticoids and androgens -\> high ACTH and high BP, high mineralocorticoids (but low RAAS activation).
519
Which hormone is elevated in Klinefelter syndrome?
FSH and LH, due to low testosterone and inhibin subsequent to primary testicular failure.
520
What is the classic presentation and the largest risk factor for Buerger disease?
Decreased distal pulses, dry gangrene, digit ulceration (mimic of PAD).
Buerger disease typically affects smokers \< 40s
521
How is premature ovarian failure diagnosed and characterized? What are the common causes?
Symptoms of menopause \< 40, including anovulatory cycles.
Idiopathic, chemo, radiation, some genetic disorders.
522
What is the cause of this image?
Pyruvate kinase deficiency (AR), resulting in splenomegaly and anemia
523
What is the cause and presentation of primary dysmenorrhea?
Diagnosis of exclusion, typically \< 30 yo
Crampy lower abdominal pain during menses without a clear explanation, though to be due to increased prostaglandin release. Treatment is OCP +/- NSAID.
524
What is the leading cause of death in patients with a ruptured proximal aortic dissection?
Cardiac tamponade.
525
What is the first-line treatment for pseudomonal infections?
Inhaled tobramycin
526
A pregnant patient experiencing fetal distress, cramping, a hypertonic uterus and vaginal bleeding without trauma suggests what condition? What are risk factors for it? What are the complications?
Placental abruption
Risk factors include smoking, cocaine use, trauma, hypertension and preeclampsia
Complications include fetal death, maternal shock and DIC
527
What is D-dimer? When might it be elevated?
D-dimer is a breakdown product from fimbrin, and is elevated in the setting of thrombosis.
528
What are fibrin split products?
They are created and measured when plasmin degrades blood clots.
529
Describe the stages of tissue damage and repair post MI
1. Wavy fibers \< 12h post MI
2. Neutrophilic infiltration and coagulative necrosis 1-3 days
3. Macrophages 3+ days
4. Granulation tissue 1 week
5. Collagen deposition 2-3 weeks
530
What is pulmonary capillary wedge pressure? How does it usually relate to central venous pressure?
It is an estimate of left atrial pressure, and usually is correlated with central venous pressure. It can be used to ascertain the degree of mitral valve stenosis.
531
What is fitz-hugh-curtis syndrome?
RUQ pain in PID due to liver capsule involvement with violin-string attachmentss.
532
What is the diagnosis based on CT? What findings do you expect on CBC?
Pulmonary fibrosis (idiopathic), a restrictive lung disease.
Expect to see elevated hemoglobin and hematocrit due to compensation.
533
What lipid-lowering drug is associated with cholesterol stones?
Gemfibrozil (and other fibrates)
534
How is MS diagnosed? What are common presentations?
Must have 2 separate attacks with 2 different lesions.
Presentation: sensory/motor deficits often in extremities, optic neuritis, cerebellar abnormalities.
535
What are the characteristics of the infective organism that should be suspected in a transplant patient who presents with fever, SOB, non-productive cough, N/V and tachypnea?
Cytomegalovirus (CMV), it is an enveloped, double-stratended linear DNA virus latent in mononuclear cells.
536
Which enzyme is deficient in hereditary fructose intolerance? How do these patients usually present?
Aldolase B: presents with a low glucose level + lethargy, tachypnea, tremors, hypothermia and diaphoresis + emesis post fruit / fruit-juice introduction.
537
What is indicated in a patient with PE subsequent to DVT? What is the mechanism of action?
Low molecular weight heparin, which activates antithrombin which in turn inhibits Xa
538
What is porphyria cutanea tarda?
Caused by defects in uroporphyrinogen decarboxylase (a cytoplasmic enzyme).
Presentation is tea-colored urine + blistering skin lesions on sun exposure.
539
What is a cystic hygroma?
Abnormal growth on a baby's neck/head caused by errors in fetal develpoment of lymphatic tissue, one or many fluid-filled cysts that tends to grow over time.. Often associated with other congenital abnormalities.
540
What is the cause of the wavy bands that characterize the first stage of tissue change immediately following an MI?
Calcium influx due to reperfusion leading to "hypercontraction"
541
What is the mechanism of action of warfarin?
It inhibits the extrinsic clotting pathway (factor VII).
542
What is the most common cause of bronchiolitis? What are the characteristic proteins and their effects?
RSV (single stranded, negative-sense paramyxovirus).
G protein attaches it to the epithelium
F protein fuses the virus to the resp epi and causes nearby membranes to merge.
543
How can you diagnose the flu?
What are the key viral characteristics?
How does influenza mutate in seasonal outbreaks vs pandemic-level infections?
Flu can be diagnosed by fever, malaise, cough and muscle aches with no nasal drainage along with a positive rapid antigen test.
Influenza is an enveloped, negative-sense, ssRNA genome with 8 segments.
Seasonal outbreaks = point mutations; pandemic = genetic reassortment
544
What is the presentation of renal papillary necrosis? What are the primary causes?
Presentation: gross hematuria, proteinuria and flank pain
causes **SAAD**
**S**ickle cell
**A**cute pyelonephritis
**A**nalgesics (NSAIDS)
**D**iabetes mellitus
545
What is the cause and presentation of diffuse esophageal spasm? How is it diagnosed?
Carused by loss of inhibitory innervation in the myenteric plexus resulting in periodic, uncoordinated non-peristaltic contractions. Dysphagia and substernal chest pain can result and it may be diagnosed by a corkscrew pattern on barium swallow.
546
What is the cause of these lesions?
Warfarin-induced skin necrosis, especially in patients with a protein C or S deficiency. Thrombosis of the skin results when warfarin depletes C and S first, leading to hypercoagulation.
547
What are the causes of dilated cardiomyopathy? How do you diagnose it?
CHF -\> elevated BNP and an S3.
Causes include: alcohol/cocaine, pregnancy, genetics, hemochromatosis, doxorubicin, coxsackie virus B and Chagas disease.
548
What is the specific epitope of the autoantibodies in goodpasture syndrome?
a3 chain of type IV collagen in the glomerular basement membrane (leads to nephritic syndrome, alveolar hemorrhage and hemoptysis).
549
Assuming full immunization and appropreiate PEP, what is the most likely disease to contract in a needlestick injury?
Hepatits C
550
How would you distinguish between bronchial asthma and chronic bronchitis?
Chronic bronchitis will present with a consistent productive cough.
551
What is the diagnosis? What are the relevant features?
Bronchial asthma: obstruction of the lumen with mucoid exudate, goblet cell metaplasia and smooth muscle hypertrophy.
552
When adding an inhaled corticosteroid for asthma management, what should you counsel? Why?
Rinse out the mouth after taking the puffer to reduce the risk of oral thrush.
553
What is a differential for a scrapable oral plaque?
1. . superficial burn
2. candidiasis
3. pseudomembranous oral ulcers e.g. aphthous, erythema multiforme etc.
3. morsicatio (chronic biting of cheek, lips or tongue)
554
What is budesonide indicated for?
It is a corticosteroid used for Crohn's, UC and allergic rhinitis.
555
What commonly used steroid requires bioactivation?
Prednisone (must be reduced to prednisolone)
556
What is the differential for a spike in the gamma region on serum protein electrophoresis?
Amyloidosis, chronic infections, CLL, Hodgkin's, malignant lymphoma, multiple myeloma, rheumatoid and other collagen diseases, Waldenstrom's macroglobulinemia, cirrhosis, or monoclonal gammopathy of undetermined significance.
557
What is the classic presentation of CLL?
Immune dysfunction, (either ITP or pure red cell aplasia) + lymphadenopathy and hepatosplenomegaly.
558
How would you distinguish between HCC caused by hepatitis B vs hepatitis C?
Hep B: can be inherited from parents, tends to occur in younger adults especially in Asia, HCC caused by integration of the viral genome
Hep C: transmitted through needle sharing or drug use, generally presents with HCC later in life due to chronic cirrhosis (malignant conversion)
559
Which features of a colonic polyp suggest the greatest potential for malignancy?
Increased size and greater surface area (so villous \> tubular)
560
What is the difference between primary biliary cholangitis and primary sclerosing cholangitis?
Primary biliary cholangitis affects the smaller bile ducts and typically presents in middle-aged women. It may lead to cirrhosis and destruction of intrahepatic ducts.
Primary sclerosing cholangitis is a common UC complication and presents with periportal fibrosis and stenosis of hepatic bile ducts.
561
How would you distinguish between a patient taking furosemide and hydrochlorothiazide on urinalysis?
Both will increase urine sodium chloride and potassium, however HCTZ will lower urine Ca2+ whereas furosamide would increase Ca2+ in the urine. Hyperuricemia and hyperglycemia are also unique to thiazide diuretics.
562
How do you treat euvolemic hyponatremia (e.g. SIADH)?
Begin with water restriction to increase plasma sodium.
If symptomatic, use 3% saline or normal saline + furosemide.
563
What are the key findings which are suggestive of AML?
Older (age\>60), microangiopathic hemolytic anemia, leukopenia, thrombocytopenia, ++myeloblasts (\>20%) with multiple auer rods on smear.
564
What is a normal anion gap? What is the differential for an elevated anion gap metabolic acidosis?
Normal is \<3x serum albumin or \< 12 mmol/L
Elevated anion gap could be MUDPILES + CAT
**M**ethanol
**U**remia
**D**KA
**P**araldehyde
**I**ron or **I**sonazid
**L**actic acidosis
**E**thanol or **E**thylene glycol
**S**alicylate (ASA, Asprin)
**CO**
**A**minoglycosides
**T**heophylline
565
What are the side effects of gastric motility agents e.g. metoclopramide?
Extrapyramidal symptoms: tremor, dystonia and involuntary movements.
566
How does the heart muscle remodel in response to untreated hypertension?
Increased systemic pressure -\> L ventricular hypertrophy (additional sarcomeres added in parallel) -\> L-sided HF -\> R-sided HF sucbsequent to increased pulmonary pressure.
567
What are some diagnostic criteria for TB? What is its virulence factor?
Fever, night sweats, productive cough with streaky blood, dyspnea and positive acid-fast stain in sputum.
Cord factor activates macrophages -\> TNF-alpha release -\> caseating granulomas. Sulfatides inhibits phagolnysosomal fusion.
568
How do you grow TB?
Lowenstein-Jensen agar
569
Cavitary lung masses and sarcoidosis can become infected by what organism? What would you expect to see on microscopy? What is the treatment?
Aspergillus fumigatus, a mold with septate hyphae branching at 45-degree angles.
Treatment is surgical removal.
570
What condition is associtaed with a t(15;17)?
Acute promyelocytic leukemia
(rapid onset fatigue, splenomegaly and bleeding)
571
A colonoscopy reveals yellow-white plaques lining the colon. What is the infective organism? What is the gold-standard test for it?
C. difficile pseudomembranous plaques (chronic watery diarrhea and crampy ambdo pain).
Gold standard is toxin assay for A and B toxin.
572
What do you see on this blood smear?
Microcytic, hypochromic anemia (most likely iron deficiency).
573
What do you see in this blood smear?
Cold agglutinin disease with clumping of RBCs
Associated with blue fingers and toes (painful), previous infection of Mycoplasma pneumoniae or EBV.
574
What are the causes of non-anion gap acidosis?
HARDASS
**H**yperalimentation
**A**ddison disease
**R**enal tubular acidosis
**D**iarrhea (most commonly)
**A**cetazolamide
**S**pironolactone
**S**aline infusion
575
What is the most likely diagnosis based on this picture of a 64yo F
Osteoarthritis
576
Gout and pseudogout affect which joints?
Large joints e.g. knee.
577
What is Job syndrome?
Failure of helper T lymphocytes to make INF-gamma
FATED
**F**acies (coarse)
**A**bcesses **(without inflammation/erythema)**
retained primary **t**eeth
increased Ig**E**
**D**ermatologic problems e.g. atopic dermatitis
578
Can you use furosemide in a patient with T2DM with pulmonary edema subsequent to CHF?
Yes!
579
What is von Recklinghausen's disease?
aka osteitis fibrosa cystica, due to untreated hyperparathyroidism.
Cystic lesions, hypercalcemia, elevated ALP and hypophosphatemia
580
How does alcohol intoxication affect the NADH to NAD+ ratio? How does this change impact glucose levels?
Oxidization to acetaldehyde and subsequently acetate increases NADH/NAD+.
High NADH results in pyruvate -\> lactate (acidosis) + stops gluconeogenesis in the liver.
581
What does this bone biopsy show?
The infective organism is a gram-negative oxidase-positive rod. What is it?
Osteomyelitis
Pseudomonas
Often introduced by IVDU
582
What is the classification of N gonorrheae?
Gram-negative diplococci
583
A boy presents with fever, rash, bone swelling and the following skin biopsy.
What is the diagonsis? What would you see on EM?
Langerhans cell histiocytosis caused by infiltration of myeloid-progenitor derived cells, more common in boys.
EM shows birbeck granules (striated, rod-like outpouchings)
584
What are associated complications of autosomal dominant polycystic kidney disease (ADPKD)?
Berry aneurysms of the circle of Willis, aortic root aneurysm, diverticulosis, mitral valve prolapse.
585
How does ADPKD present?
Hematuria (sometimes the only presenting symptom), flank pain, HTN, uTI and progressive renal failure
586
What does a 40% HbS indicate?
40% abnormal hemoglobin, suggestive of sickle cell trait (ie heterozygote) which will likely be otherwise silent.
587
What is the embryonal origin of pheochromocytoma?
Neural crest cells.
588
Low tryptophan can lead to what vitamin deficincy? How would this present?
B3 (niacin) = pellagra
Glossitis
3D: Diarrhea, Dementia, Dermatitis (and Death)
589
How does restrictive lung disease present on PFT?
Decreased TLC, FRC, RV, FVC and FEV1
Normal or increased FEV1/FVC
590
Name the organism on this acid fast stain
What is the appropriate antibiotic?
Nocardia (gram positve, weakly acid-fast, long branching filaments). Opportunistic (think immunocompromised)
Sulfonamides (TMP-SMX) preferred.
591
What is the mechanism of action of sulfonamides?
blocks nucleotide synthesis by inhibiting dyhydropteroate synthase.
592
What is the pathology on this ECG?
What are the inherited causes of this pathology?
Long QT interval (\>2 large boxes on ECG)
Jervell and Lange-Nielsen syndrome (autosomal recessive KCNQ1 or KCNE1 mutation): bilateral sensorineural hearing loss + defective voltage-gated K+ channels.
Romano-Ward (autosomal dominant K+ and Na+ channel defect) does not have hearing loss.
593
Which hormones share an identical alpha-subunit to bHCG?
TSH, LH and FSH
594
What is a conduction aphasia? Which area of the brain is affected?
Conduction aphasia = unable to repeat specific words or phrases due to a lesion in the arcuate faciculus (which connects broca and wernicke areas)
595
Differentiate between avoidant and schizoid personality disorders?
Avoidant = social inhibition, feeling inadequate, hypersensitive to negative evaluation
Schizoid = voluntary social withdrawal, indifferent to human interaction.
596
Which cells are activated by cytokines and growth factors to form the fibrous cap overlying the atheroma?
Vascular smooth muscle cells
597
Which cells secrete gastrin? What does it do?
G cells secrete gastrin, which normally induces parietal cells in the stomach to secrete acid.
Zollinger-ellison = pancreatic gastrinoma), presents with refractory PUD
598
How does desquamative interstitial pneumonia typically present? What cells end up filling the alveolI?
Gradual shortness of breath + dry cough with hypoxemia in a middle-aged smoker.
Increased dead space and Decreased TLC
On CT, you would see diffuse ground glass opacity with cystic changes.
Alvioli are filled with pigment-laden macrophages (NOT epithelium)
599
What are the signs of FASD? When should you suspect moms of having alcohol consumption?
Small eyes, narrow droopy eyelids, small palpebral fissures, smooth philtrum, verminion border on thin upper lip
Also presents with limb dislocations, intellectual disability, heart defects.
Consider liver stigmata and signs of chronic alcohol use e.g. esophageal varices.
600
How would you distinguish between frontal lobe and amygdala lesions?
Both present with disinhibition and impaired judgement, but amygdala lesion presents with memory problems.
601
Which conditions are associated with the following lung histology:
Alveolar fluid and hyaline membranes
Infiltration of eosinophils and CD4+ cells
Infiltratration of macrophages and CD8+ cells
1. Adult respiratory distress syndrome
2. Asthma
3. Chronic bronchitis
602
What are the diagnostic criteria for chronic bronchitis?
Productive cough at least 3 mos/year for 2 years. Obstructive pattern on Pft; FEV1:FVC \< 0.7
603
What is the classification of the most common viral causes of meningitis?
Enteroviruses - nonenveloped SS linear +RNA
in neonates, children 6+ and adults to age 60 - HSV - enveloped dsDNA with glycoprotein
604
What is the systemic antifungal recommended for tinea corporis? What is its mechanism of action?
Griseofulvin
Disrupts microtubules (alpha/beta tubulin dimer).
Disulfiram-like reaction when mixed with alcohol.
605
How do you calculate the filtration fraction from GFR and renal blood flow?
FF = GFR / renal plasma flow
Renal plasma flow = renal blood flow \* (1-hematocrit)
substited: FF = GFR / (RBF \* (1-hematocrit))
606
What is Meigs syndrome? What is the classic triad? What would you see on biopsy? What do these tumours secrete
An ovarian fibroma which presents with abdo fullness, ascites, and pleural effusion.
On biopsy: spindle cells and collagen.
No sex hormone secretion.
607
What pathology is indicated when an ECG shows occasional premature ventricular contractions?
No underlying pathology.
608
What drugs should be used to treat Addison disease?
Dexamethasone (glucocorticoid) + Fludrocortisone (mineralocorticoid)
609
What TB drug has a classic side effect of turning body fluids orange or red? What is its mechanism of action?
Rifampin, blocks RNA synthesis via blockage of DNA-dependent RNA polymerase.
610
How would damage to the lateral cords of the brachial plexus present?
Lateral: -\> musculocutaneuous nerve and median nerve, lateral forearm sensory loss, weakness to elbow flexion and supination, wrist flexion and extension of lateral digits + sensory loss over the thenar eminannce and both sides of the lateral 3 digits.
611
How would damage to the posterior cord present?
Posterior -\> Axillary and medial nerves; inability to abduct the shoulder and elbow/ wrist / and MCP extension
612
How would damage to the medial cord of the brachial plexus present?
Medial -\> median + ulnar nerve: weakness of wrist flexion but varies, flexion of medial fingers, abduction/adduction of digits., sensory loss over the medial 1.5 fingers and the hypothenar eminence
613
What is the defective enzyme and the clinical presentation of I cell disease?
Defect in N-acetylglucosaminyl-1-phosphotranspherase (makes mannose-6-phos to target proteins to lysosomes)
Clinically presents as skeletal abnormalities, coarse facial features, corneal clouding + psychomotor retardation.
614
What is the arrow pointing to? What disease process could result in this slide?
Mallory bodies: eosinophilic inclusions in cytoplasm of necrotic hepatocyteso commonly found in alcoholic hepatitis.
615
Which thumb muscle is innervated by the ulnar nerve?
Adductor pollicis
616
What are councilman bodies?
Eosinophilic globules due to apoptosis of individual hepatocytes, can occur with yellow fever.
617
What is the causative organism and treatment for a small painless ulcer on the genitals which proceeds to swollen, ulcerated inguinal lymph nodes 4-6 weeks later?
Chlamydia trachomatis type L1-3
Treat wyth doxycycline
618
What is shown on this ECG? What drug can cause this effect?
Mobitz II heart block (dropped beats with no PR lengthening)
Can be caused by bupivicaine
619
What is the mechanism by which an antibiotic potentiates warfarin's effect on PT and increases PTT?
Via loss of gut bacteria leading to poor absorption of vitamin K.
620
How does chagas disease spread? How does it present?
Chagas disease is caused by the intracellular protozoan Trypanosoma cruzi. Spread by reduviid bugs. Presents with myocarditis and dysmotility of hollow organs.
621
What syndrome is associated with endocardial cushon defects in a newborn? What might you see on triple screen prenatally?
Down syndrome; low AFP, high BhCG, low estriol.
622
What drugs produce disulfiram-like reactions with alcohol?
Sorry Pals, Can't Go Mingle
**S**ulfonylureas (tolbutamide)
**P**rocarbazine
**C**ephalosporins (cefamandole and cefaperazone)
**G**riseofulvin
**M**etronidazole
623
How does a cleft lip happen?
Failure of the maxilary + medial nasal prominences (philtrum + upper lip to lateral border of nose) or lateral nasal prominences (gap between midphase and lateral nose) to fuse.
624
What is the mechanism of inheritance of chronic granulomatous disease?
X-linked recessive
May present in girls via skewed x-inactivation.
625
When a question appears to give you extraneous information that could be "explained away" as not part of the diagnosis, what should you do?
Look for one diagnosis that explains even the "apparently extraneous" symptoms.
626
Where in the brain does glioblastoma multiforme present?
The cerebrum, never in the cerebellum
627
When multiple masses are found on imaging, what should you be thinking of?
Metastasis, less likely to be a primary tumor from that organ.
628
What is the difference between a slip and a lapse?
A slip is an error of attention, e.g. due to high stress. A lapse is an error in memory, i.e. forgetting to do something.
629
What is the difference between acting out, displacement, projection and reaction formation?
Acting out: using actions to cope with stressors or emotional conflict rather than addressing thoughts and emotions.
Displacement: transferring or attributing feelings to a neutral person or object
Projection: misattributing internal impulses to an external source
Reaction formation: a "warded-off" idea or feeling is replaced by the opposite (like denial on steroids)
630
This person presents with low-voltage QRS complexes, an ejection fraction of 55%, crackles at lung bases and lower-extremity edema. Based on these symptoms and cardiac biopsy below, what is the diaglosis? What is the etiology?
Amyloidosis
Primary due to Ig light-chain deposition from bone marrow antibody production or secondary due to chronic inflamation.
Produces restrictive cardiomyopathy (normal ejection fraction)
631
What are the major side effects of doxycycline?
Photosensitivity, GI distress, and teeth discolouration (in children \< 8)
632
What is the deficient enzyme, inheritance and characteristic presentation of lesch-nyhan syndrome?
HGPRT (hypoxanthine-guanine phosphoribosyltransferase), XR
Hyperuricemia (orange crystals in diaper)
Gout
Pissed-off (self-mutilation, aggression)
Retardation
dysTonia
633
What conditions are associated with target cells?
liver disease, iron deficiency, thalassemias and postsplenectomy.
634
When does post-streptococcal glomerulonephritis usually present? What is the characteristic kidney finding?
10-14 days post-infection, usually in children. Hematuria / nephritic syndrome
635
Which types of E. Coli are associated with bloody diarrhea? Traveller's diarrhea?
Bloody diarrhea: Enterohemorrhagic (EHEC e.g. O157:H7) and enteroinvasive (e.g. O124)
Non-blody: enterotoxigenic (ETEC)
636
What is first-line pharmacotherapy for smoking cession? What is the mechanism of action?
Bupropion (norepinephrine + dopamine reuptake inhibitor)
varenicline (nicotine receptor partial agonist)
637
What medication is given that acts centrally for HTN? What is the mechanism of action?
Clonidine, an a2-adrenergic agonist lowers sympathetic tone from CNS, thereby lowering blood pressure. Pts must be compliant with medication. bc missed doses can cause spikes in BP\>
638
What is fulminant hepatitis?
Very rapid deterioration due to massive necrosis of the liver (can be due to viral hepatitis, drug-induced) leading to liver failure, hepatorenal syndrome, DIC and portosystemic encephalopathy progressive to coma and cerebral edema.
639
What is insubordination?
Defiance of authority or refusal to obey orders.
640
How would pulmonary capilary wedge pressure change in the setting of septic shock?
Initially normal, then decreasing as increased permeability of the lung endothelium leads to fluid loss.
641
What organism causes bloody diarrhea more often than Salmonella and Shigella?
Campylobacter jejuni
642
What are the signs of antimuscarinic toxicity? What is the treatment?
Fever, rapid pulse, dry mouth, dry flushed skin, cycloplegia, constipation and disorientation
Treat with physostigmine (anticholinesterase inhibitor)
643
Describe the mechanism of action of cephalosporins.
Inhibits cell wall synthesis by inhibiting transpeptidases (which cross-link peptidoglycans)
644
What are the risk factors for pancreatic adenocarcinoma? What sign should raise your index of suspicion for this cancer?
Smoking, age (65-75), history of chronic pancreatitis, some hereditary syndromes.
Courvoisier sign: a palpable, nontender gallbladder (caused by pancreatic obstruction of the bile ducts)
645
What treatments are used for lead poisoning? What about arsenic, mercury or gold poisoning?
EDTA for lead, also can use dimercaprol and succimer for all of the above.
646
What is the mechanism of the drug used to treat latent TB infection?
Rifampin decreases messenger RNA synthesis by inhibiting bacteral DNA-dependent RNA pol
647
What pathologic finding would lead to this liver biopsy?
This is a cirrhotic liver with micronodular cirrhosis (pink nodules surrounded by cirrhotic tissue) which is associated with persistent activation of stellate cells.
648
What is the embryonal origin of the ductus arteriosus?
The sixth aortic arch
649
How would you differentiate asbestosis from silicosis?
Both are restrictive lung diseases, however silicosis often presents with **eggshell calcifications in the lymph nodes of the upper lobes of the lungs,** whereas asbestosis is typically associated with **lower lung pathology** as well as increased risk of **mesothelioma and bronchogenic carcinoma.** Asbestosis industry associations are with **shipbuilding roofing and plumbing.**
650
Which drugs are associated with crystal-induced nephropathy?
Acyclovir, sulfonamide antibiotics, ethylene glycol, megadoses of vitamin C, methotrexate, protease inhibitors.
651
What is the blood supply to the ovary?
The ovaries receive blood from the ovarian arteries which are direct branches of the abdominal aorta.
652
Infants of diabetic mothers are at greater risk of being born with this condition which causes early cyanosis.
Transposition of the great vessels.
653
Why are grain products supplemented with this one – carbon transfer coenzyme?
Folate is important for the development of the neural tube by a closure of the neural folds at four weeks of pregnancy.
654
What is the difference between methanamine (Gomori) silver stain and regular silver stain?
Methenamine silver = *Pneumocystis jiroveci*
Silver stain = *Legionella pneuemophilia*
655
What is the mechanism of action for the drug used as primary treatment for shingles?
Famciclovir is activated by viral thymidine kinase into acyclovir monophosphate which is a nucleoside analog resulting in chain termination by viral DNA polymerase.
656
What type of hypersensitivity reaction characterizes myasthenia gravis? What is affected?
Type II or direct, antibody-mediated hypersensitivity targeted to the *postsynaptic* AChRs
657
Describe the three stages of Lyme disease progression
1. Flulike symptoms and classic target shaped rash
2. neurologic involvement including facial palsy, cardiac involvement (atrioventricular conduction delay)
3. asymmetric arthritis or subacute encephalopathy (rarely)
658
A characteristic daily fever spike accompanied by polyarthritis and a macular salmon pink rash, leukocytosis, anemia, and elevated ESR is most likely what disorder? What are the diagnostic criteria? What is the first referral that you need to do?
Systemic JIA, fevers must be present for more than two weeks and arthritis for more than six weeks. Should refer to ophthalmology to evaluate for uveitis.
659
Distinguish between fetal presentations of remnants in the posterior urethra versus ureteropelvic junction obstruction.
You PJ obstruction is typically unilateral hydronephrosis with dilatation proximal to the obstruction (i.e. not of the bladder). A persistent urogenital membrane will present as posterior urethral valves at the junction of the bladder and urethra.
660
What is heparin induced thrombocytopenia? What is the appropriate treatment?
Typically occurring 5 to 14 days after heparin use, IgG antibodies against heparin bound platelet factor for leads to platelet activation, clot formation, and thrombocytopenia.
Treatment is stopping heparin and giving direct thrombin inhibitors such as are argatroban or lepirudin.
661
What is the most specific autoantibody for rheumatoid arthritis?
Anti-CCP (citrullinated protein)
662
Name this tumor found in an eight year old boy. What are the key characteristics?
Well-circumscribed tumor with a large **cystic** component and a brightly enhancing mural nodule. Typically found in the posterior fossa, this is a (benign) **pilocytic astrocytoma**, the most common primary brain tumor in children
663
What drugs are known to cause drug-induced lupus erythematosus?
Hydralazine, procainamide, TNF alpha inhibitors (etanercept), methyldopa, isoniazid, phenytoin.
664
A rapid deceleration injury is most concerning for what vascular trauma?
Rupture of the aortic Isthmus, just distal to the left subclavian.
665
What is the vascular origin of the following hemorrhages?
1. Epidural hematoma
2. subdural hematoma
3. subarachnoid hemorrhage
4. intra-parenchymal hemorrhage
1. Rupture of the middle meningeal artery
2. rupture of the bridging veins
3. ruptured berry aneurysm
4. intraparenchymal hemorrhage which is atraumatic is typically caused by hypertension but can also be due to amyloid and uropathy or recurrent lobar hemorrhagic strokes, vasculitis, or neoplasm.
666
A woman presents with progressive proximal muscle weakness without pain, fatigability, or rash. What is the most likely diagnosis? What are characteristic findings on investigations? What is the treatment?
Polymyositis associated with endomysial infiltration of CD8 positive T cells and overexpression of MHC class I.
On investigations elevated creatine kinase, antinuclear antibody, anti-jo-1, anti-SRP, anti-Mi-2. Muscle biopsy shows Perimysial infiltration. Vesicular atrophy with patching necrosis. Can occur in a paraneoplastic syndrome associated with ovarian adenocarcinoma, lung cancer, colorectal cancer, and non-Hodgkin lymphoma.
Corticosteroids are first-line treatment.
667
What are the characteristic findings of the disease associated with this intestinal biopsy? What is the classic presentation and findings on investigation?
Associated with northern European descent, steatorrhea, iron deficiency anemia (refractory to treatment).
Also associated with dermatitis herpetiformis which is characterized by clusters of pruritic, papular or bullous lesions on the trunk and extensor surfaces.
Intestinal biopsy will show villus blunting with crypt hyperplasia and lymphocytic infiltration into the lamb you propria.
Investigations positive for antiendomysial or anti-TTG antibodies.
668
What is the diagnosis based on this intestinal biopsy from a patient with a history of abdo pain and bloody diarrhea, as well as tender, erythematous bumps on the shins.
This shows a noncaseating granuloma consistent with Crohn's disease.
669
Distinguish between spermatocele, hydrocele, and varicocele
1. Spermatocele: a cyst due to dilated epididymal duct or rete testis. It is a painless, paratesticular fluctuant nodule
2. Hydrocele is a fluid collection in the scrotum which transilluminates
3. Varicocele is the "bag of worms" dilated veins in the pampiniform plexus of the testicle, which normally cools the testes (can lead to fertility problems), painful, does not transilluminate.
670
What drugs are associated with ATN?
Antibiotics: Aminoglycosides, beta-lactams, rifampin and vancomycin
Antivirals: Acyclovir, cidofovir, tenofovir, foscarnet
Other: cisplatin, contrast dies, IVIg
671
What adverse effects are associated with piperacillin? What are the target organisms?
antipseudomonal. Associated with hypersensitivity reactions and interstitial nephritis (eosinophils on UA)
672
What are complications of untreated Graves' disease?
Chronic proptosis/lid retraction can lead to corneal ulceration and blindness
Thyroid-stimulating immunoglobulins also can cause pretibial myxedema (big red rash on legs)
Osteoporosis (due to stimulation of osteoclast activity)
Neonatal hyperthyroidism (in pregnant patients)
673
What is the appropriate treatment for Lyme in pregnant patients or children \< 8yo?
Amoxicillin
674
A family history positive for leukemia, adrenal and breast cancer at a young age is most likely caused by a mutation in which gene?
TP53 (this is Li-Fraumeni syndrome).
675
What is the defective enzyme and presentation of metachromatic leukodystrophy? What are the findings on biopsy?
Arylsulfatase A, causing accumulation of cerebroside sulfate, which causes metachromasia (toluidine blue appears reddish/pink). Biopsy will also show evidence of demyelination.
Classic presentation is regression or developmental delay in gross motor i.e. muscle weakness.
676
What are the effects of a nonspecific beta-blocker (e.g. nadolol)
Beta1 + Beta2 antagonism; B1 is cardiac so decreased HR, contractility and renin release, B2 is vascular; inhibition causes vasoconstriction and increased systemic vascular resistance.
677
What is the bacterial component that is used for Haemophilus influenzae vaccine?
The polyribosylribitol phosphate (type B polysaccharide) capsule.
678
Where on the tRNA does is the amino acid attached?
The 3'-CCA amino acid acceptor site.
679
What findings on ABG would you expect to see in a patient with a PE?
Respiratory alkalosis + hypoxemia
High: pH
Low: PCO2 and PO2
Unchanged: HCO3 (not enough time for compensation)
680
How do you interpret UA findings with suspected UTI?
+ve leukocyte esterase = WBCs
+ve nitrite = gram-negative bacterial species e.g. E. coli (most common cause of UTI)
+ve urease test = Staph saprophyticus, Proteus, Klebsiella
681
Pigmented cartilege and dark urine is caused by what enzyme deficiency?
Alkaptonuria due to deficiency of homogentisic acid oxidase (tyrosine degradation pathway).
682
What hormone disruptions are present in the setting of PCOS?
High LH and insulin resistance, leading to hyperinsulinemia, hyperglycemia and hyperlipidemia.
683
Where do aspirated foreign objects usually end up in the lung?
Right lung mainstem bronchus (and further into the intermediate bronchi if it's small).
684
What treatment can be used to prevent cluster headaches?
verapamil
685
At what age is an upgoing Babinski normal?
\<12 months of age.
686
What are the signs/symptoms of Guillain-Barré Syndrome? What might you be worried about on ABG?
Ascending weakness/paralysis, steppage gait (foot drop), leading to respiratory paralysis.
Hypoventilation -\> respiratory acidosis = LOW pH, High CO2 and no change in HCO3.
687
What is the first-line treatment for delirium?
Treat the underlying condition, give a low-dose antipsychotic (e.g. haloperidol).
688
Why is isoniazid not used as monotherapy in active TB?
Monotherapy increases the risk of developing resistant TB due to mutations lowering activity of bacterial catalase peroxidase.
689
What is the mechanism of action of infliximab, etanercept or adalimumab?
Binds TNF-alpha and blocks activity. Does not target the TNF-receptor
690
What is the etiology and diagnosis in this young boy who presents with multiple hamartomatous polyps in the small intestine?
Peutz-Jehgers syndrome, caused by mutations in STK1. Hyperpigmented macules can also present in/on lips, mouth, hands and genitalia
691
What is the classic presentation of diverticulitis? What is the finding on histology? On imaging?
`Crampy LLQ abdo pain with diarrhea and a fever.
Focal areas of weakness in the muscularis propia
Pericolic fat staining + Thickened colonic wall.
692
What is the differential for a megaloblastic anemia? How do you distinguish between etiologies?
Either vitamin B12 or folate deficiency. Diet-related more likely to be folate as stores more rapidly depleted. B12 deficiency also presents with neurologic symptoms including numbless, paresthesias or gait abnormalities (B12 is a cofactor for methylmalonyl CoA mutase)
693
What si the effect of angiotensin II on the efferent renal arteriole cells?
Ang II -\> Gq receptor -\> increased PLC
694
What is a zenker diverticulum?
A false diverticulum presenting in elderly men between the thyropharyngeal and cricopharyngeal parts of th e inferior pharyngeal constrictor.
695
How does GERD present in an infant?
Persistent wheezing, night-time cough, decreased appetite, poor weight gain and intermitted regurgitation.
696
What prophylaxis should be given to persons with large BSA burns?
Omeprazole or PPI to prevent a Curling ulcer (a fundal ulcer)
697
What is growing on this culture? What is the virulence mechanism?
Pseudomonas aeruginosa; makes exotoxin A which ADP ribosylates + inhibits EF2, stopping protein synthesis.
698
What therapy is indicated for post-streptococcal glomerulnephritis?
Supportive therapy only; some role for prednisone in very severe cases with renal failure.
699
What is the diagnosis? What would you see on utrasound bfore birth?
Tracheoesophageal fistula; 2/3 of cases present with polyhydramnios.
700
Which AIDS-defining illness is associated with an encapsulated yeast with narrow-based budding? What is the vector associated with transmission?
Cryptococcus neoformans meningoencephalitis.
Pigeon droppings (e.g. "city garden")
701
What fungal infection is characterized by a small intracellular yeast? Where is it typically found? What's the transmission vector? What would you see on pathology?
Histoplasmosis, found in the Mississipi and Ohio river valleys and commonly tranmitted by bird and bat droppings. Lung granulomas with calcifications.
702
What is this fungus? What are the key characteristics?
Aspergillus fumigatus
Mold with septate hyphae that branch in a V-shaped 45-degree angle
703
Name this fungus. What are its special characteristics? Where is it found? What are the symptoms?
Blastomyces: it's a dimorphic fungus (mold in the cold, yeaste in the heat). Found in soil in wooded areas east of the Mississippi River.
Symptoms of pneumonia: cough, fever, shortness of breath, sometimes hemoptysis.
704
Name the organism: a budding yeast with pseudohyphae?
*Candida albicans*
705
How is glucose sensed by the pancreatic beta islet cells?
Glucose enters beta cells by GLUT2. When glucose falls, ATP levels fall, leaving ATP-sensitive K+ channels open.
When glucose levels rise and K+ channels close, membrane depolarization leads to Ca2+ entry into the cell and activation of exocytosis of insulin granules
706
Which cancers is a RET mutation associated with?
MEN-2A is Parathyroid hyperplasia or tumor -\> hypercalcemia
MEN-2B marfinoid habitus, ganglioneuromas in mounth / GI tract.
Both: medullary carcinoma of the thyroid, pheochromocytoma.
707
How do you differentiate between actue stress disorder and PTSD?
Acute stress disorder is a disturbance in function associated with a traumatic event between 3days and 1 month post-event. PTSD is \>1 month.
708
Describe the timelines and pathology of different types of graft rejection.
Hyperacute (minutes to hours) due to pre-existing antibodies reacting with donor antigen -\> graft vessel ischemia and necrosis
Acute (weeks to months) due to activation of T cell activation against donor MHCs -\> vasculitis with lymphocytic infiltrate
Chronic (months to years) -\> CD4+ T cells respond to recipient APCs presenting donor peptides -\> proliferation of vascular smooth muscle, parenchymal atrophy, interstitial fibrosis
Graft-versus-host: Grafted T cells proliferate and reject host cells -\> symptoms include maculopapular rash, jaundice, diarrhea and hepatosplenomegaly.
709
What is rotor syndrome?
AR disease with conjugated hyperbilirubinemia caused by impaired uptake and excretion of bil (without abnormal pigment in hepatocytes).
Similar to Dubin Johnson.
710
How would you treat a patient on an antipsychotic who presents with fever, muscle rigidity and tachycardia?
This is neuroleptic malignant syndrome, and can be treated by muscle relaxants e.g. dantrolene (which blocks Ca2+ release from SR).
711
How would you differentiate between toxoplasmosis or CMV infection in HIV patients?
CNS Toxoplasmosis typically presents with encephalitis, focal neurlogic deficits and a ring-enhancing lesion + mass effect.
CMV casues retinitis + diarrhea, but not a specific visual field cut and not typically seizures.
712
What disease presents with mixed upper/lower motor neuron findings in the extremities? What pathology would you see in the spinal cord?
Amyotrophyc lateral sclerosis (ALS) with degeneration of the anterior horns of grey matter (LMN symptoms of weakness, atrophy and fasciculations) and corticospinal tracts (UMN symptoms i.e. hyperreflexia)
713
Which antibiotics act at the 30S subunit of the bacterial ribosome? The 50S subunit?
buy AT 30, SCELL at 50
30S: aminoglycosides and tetracyclines
50S: Streptogramins, Chloramphenicol, Erythromycin (macrolides), Clindamycin and Linezolid
714
What is the cause of these lesions in this HIV+ve individual? What other symptoms may occur? What is the treatment?
These lesions are characteristic of Kaposi sarcoma (HHV-8). Other symptoms include lymphedema or spread to oral mucosa, GI or respiratory tract.
Therapy is continued HAART, but can inject vinblastine or provide interferon-alpha or systemic chemo if severe.
715
Where is the fluid localized in a testicular hydrocele?
Between the parietal and visceral layers of the tunica vaginalis.
716
Describe the bacterial characteristics of the most common causes of meningitis in the neonate.
E. coli: gram -ve bacillus, lactose fermenting
L. monocytogenes gram+ve bacillus, catalase +ve
GBS: gram +ve cocci in chains, beta-hemolytic, catalase-negative, and facultative anaerobe
717
Describe the key differences between and HMO or a PPO (preferred provider organization) plan.
HMO -\> care coordinated through PCP and specialists require a referral, no coverage out-of-network, have lower premiums
PPO -\> Can choose any provider and book appointments with specialists directly. Will reimburse out-of-network but higher premiums
718
What type of stones is most common in people with Crohn disease? What urine pH are they associated with?
Calcium oxalate stones—acidic urine
719
What embryological structure forms the scrotum? What does it form in girls?
The labioscrotal swelling (forms labia majora in girls)
720
What drugs are associated with avascular necrosis of the femoral head?
Long-term systemic steroid use
721
What symptoms are suspicious for carcinoid syndrome? What would you find on UA?
Wheezing, with episodes of facial flushing and diarrhea
5-hydroxyindoleacetic acid.
722
What do each of the following nuclei of the hypothalamus regulate?
Lateral nucleus
Supraoptic nucleus
Ventromedial nucleus
Posterior nucleus
Lateral nucleus - hunger
Supraoptic nucleus - osmoreceptors (also in the paraventricular nucleus)
Ventromedial nucleus - eating
Posterior nucleus - thermoregulation
723
When would you use ezetimibe? Gemfibrozil? Cholestyramine? What are their mechanisms
Ezetimibe (PCSK9 inhibitor) can be used when patients have high LDL that isn't well controlled by statins
Gemfibrozil is a fibrate that decreases triglyceride levels (note increases risk of rhabdo when combined with a statin)
Cholestyrmamine (bile acid resin) binds bile acids and reduces uptake, but also reduces uptake of other meds.
724
What part of the GI tract is most at risk during a AAA repair?
The sigmoid colon, due to the IMA branch point location along the aorta.
725
What are the symptoms of phenylketonuria (PKU)?
Strange odor, pale skin, hyperreflexia, developmental delay and eczematous rash.
726
What lesion produces a positive Romberg?
the medial lemniscus (disrupts contralatal proprioception)
727
What symptoms are consistent with primary adrenal insufficiency? What test can be done as part of the workup?
Hypotension, weight loss, gum hyperpigmentation, hyponatremia and hyperK+.
Can use metyrapone to decrease serum cortisol (blocks conversion from 11-deoxycortisol). In primary insufficiency, the ACTH goes up as cholesterol goes down; in secondary insufficiency the ACTH doesn't compensate for the drop in cortisol.
728
What infection in an individual with AIDS could result in vision loss? How would you treat?
CMV retinitis; treat with Ganciclovir
729
What are the toxicities of ganciclovir?
Leukopenia, neutropenia, thrombocytopenia and hemolytic anemia
+ nephrotoxicity
730
How does dwarfism differ from GH deficiency?
In GH deficiency, limbs and heads will be proportionately smaller, dwarfism has disproportionately large heads and short limbs
731
What gene is associated with dwarfism? What is the inheritance and risk factor for mutations?
FGFR3 gain of function, autosomal dominant, advanced paternal age.
732
What is the histology characteristic of subacute thyroiditis?
Inflammatory infiltrate with multinucleated giant cells
733
Tall, crowded follicular epithelial cells with scalloped colloids are diagnostic for what thyroid disease?
Graves disease
734
What is the characteristic histology of toxic multinodular goiter?
Focal patches of hyperfunctioning follicular cells distended with colloid
735
What is Reidel thyroiditis?
Thyroid tissue replaced with inflammatory infiltrate (fibrosis / fibrosclerosis) -\> hypothyroidism.
736
What are the six criteria for allergic (eosinophilic) granulomatosis with angiitis?
Asthma
Eosinophilia
Paranasal sinusitis
Pulmonary infiltrates
Vasculitis + extravascular eosinophils
Polyneuropathy
4/6 for diagnosis with pANCA
737
What is the physiologic function of vasoactive intestinal peptide?
Increases water + electrolyte secretion into lumen and relaxes smooth muscle and sphincters.
738
Hypersegmented neutrophils is characteristic of what deficiency?
Folic acid deficiency
739
What is abnormal about this ECG? What is the cause?
Peaked T waves, characteristic of hyperkalemia
740
When you are converting a probability to a percentage, what do you have to be careful of?
Make sure you multiply by 100 when converting to a percentage.
741
What is viral complementation?
When one virus lacks a necessary protein to replicate and borrows it from a co-infecting virus or other source.
742
How do you differentiate clinically between IgA nephropathy and post-strep glomerulonephritis?
Timing of symptoms: IgA nephropathy is concomittant with infection, whereas PSGN is 3-6 weeks *after* infection.
Additionally, complement decresases in PSGN but not in IgA nephropathy.
743
Differentiate between the cause and presentation of post-streptococcal glomerulonephritis and rheumatic fever
PSGN presents with kidney changes, rheumatic fever does not.
RF is caused by GAS infection and cross-reactivity of antibodies; PSGN is due to type III reaction with immune complex deposition
744
What causes palmar erythema and spider angiomas with liver disease?
Hyperestrinism
745
Differentiate between Alport disease and Goodpasture syndrome
Alport is an inherited disease due to mutation of collagen IV leading to sensorineural hearing loss, ocular defects and hematuria, Goodpasture is due to autoimmunity against glomerular basement membrane + can have alveolar involvement leading to hemoptysis.
746
Describe the arm movement of the subscapularis muscle
Adduction and internal rotation
747
How does infraspinatus and teres minor move the arm?
Both externally rotate; teres minor adducts.
748
Differentiate primary myelofibrosis and essential thrombocythemia
primary myelofibrosis initially presents with myeloid proliferation followed by fibrosis and loss of hematopoetic cells (dacrocytes).
Essential thrombocythemia is a diagnosis of exclusion with isolated high levels of megakaryocytes and platelets (some abnormal on blood smear)
749
What symptoms would you expect from someone with this jejunal biopsy?
Migratory arthritis, abdo pain, steatorrhea, weight loss
Caused by whipple disease (Tropheryma whipplei)
750
What is the mechanism of action of bactracin? What is it used for?
Inhibits translocation of D-ala-D-ala to the outside of the bacterial cell. Used topically due to high risk of nephrotoxicity if administered IV.
751
What is the classic presentation of aspirin-induced asthma? How is it differentiated from allergies?
Aspirin intolerance, nasal polyps, and adult-onset asthma.
Allergies are typically presented with sneezing and itchy red eyes as well as seasonal association.
752
What process limits airflow during forced expiration?
Positive pleural pressure compresses the airways, leading which limits airflow.
753
What hormone causes the basal body temperature to increase after ovulation?
Progesterone
754
What is the mechanism of action and side effect of glyburide?
Increases pancreatic insulin by depolarizing beta cells; causes hypoglycemia.
755
What medications can be used to treat Graves disease? What is their mechanism of action?
Thioamides (propylthiouracil and methimazole) block iodination of tyrosine and inhibit thyroid peroxidase (coupling).
756
Which arteries are spared in polyarteritis nodosa?
The pulmonary arteries
757
What are the side effects of clozapine? What is its indication?
Drug-induced agranulocytosis, mouth and throat ulcers, myocarditis, weight gain, sialorrhea. Used for refractory schizophrenia (esp. as it has less tardive dyskinesia)
758
Distinguish between neurofibromatosis type 1 and 2.
Type 1: due to neurofibromin mutation (chr. 17) leading to cafe-au-lait spots (\>6), axillary and inguinal freckles, iris hamartomas (Lisch nodules), neurofibromas and optic gliomas.
Type 2: due to merlin mutation (chr 22) leading to bilateral vestibular schwannomas / oth CN schwannoma, intracranial meningioma, peripheral neuropathy, cataracts and cutaneous tumors.
759
What metabolic disturbance can be caused by metformin?
Lactic acidosis (AGMA) due to increased lactic acid production in intestines and reduced hepatic gluconeogenesis (must check kidney function)
760
Which hematoma crosses suture lines? which does not? What other symptoms may accompany the latter?
Subdural hematoma = cross suture lines
Epidural hematoma does not; presents with lucid interval, increased ICP can cause uncal herniation leading to ipselateral CN III palsy.
761
Histologically, what would you see in someone with fistula, crampy abdominal pain and a positive guiaic test.
Noncaseating granulomas and transmural inflammation (crohn disease)
762
A positive rapid plasma reagin test (or VDRL test) with a negative treponemal antibody test should make you think about?
SLE (they should both be positive in syphilis
763
What is the difference between actinic keratosis and seborrheic keratosis?
SK is flat, greasy and pigmented and typically a benign neoplasm in older adults
AK is a precancerous lesion consisting of a small, rough, erythematous/brown papule//plaque.
764
What drug must be administered alongside imipenem? What is its mechanism of action?
Cilastin, which inhibits dehydropeptidase-1, a PCT enzyme which metabolizes imipenem.
765
What is psittacosis? What would you see on histology?
Pneumonia with fever, headache, malaise and non-productive cough. Due to Chlamydophilia psittaci infection, typically carried by birds.
Giemsa stain shows cytoplasmic inclusion bodies.
766
What causes mumps? What is the typical presentation?
RNA paramyxovirus infection causis parotitis, orchitis, pancreatitis (can present with acute epigastric pain) and meningitis.
767
What protozoal infections are treated with metronidazole? Which are treated with praziquantel?
Metronidazole for GET GAP (Giardia, Entamoeba, Trichomonas, Gardnerella vaginalis, Anaerobes and H **p**ylori (if allergic to penicillin).
Praziquantel for schistocytosis and cestodes (tapeworms)
768
Hemorrhagic cystitis in someone treated with cyclophosphamide is associated with what condition?
Fanconi anemia (sensitivity due to chromosomal breakage in response to DNA-damaging agent).
769
How are helper T cells activated? What occurs with incomplete activation?
2 signals req'd for activation: presentation of antigen via MHC class II APC and a co-stimulatory signal via B7 protein (CD80/86) which interacts with CD28 on T cell.
Without the latter signal, T cell becomes anergic and refractory to future stimulation (peripheral tolerance).
770
Describe the sequence of events that leads to anaphylactic shock
Cross-linking of IgE receptors on mast cells and basophils leads to degranulation -\> vasodilation and leaky capilaries.
771
People who are obtunded or with history of alcoholism are at increased risk for what kind of infecitons? What pathogens are responsible?
Aspiration pneumonia caused by Peptostreptococcus, Bacteroides fragilis, Prevotella
772
Describe the 5 components of the Apgar score
Activity (extremity movement)
Pulse
Grimace (irritability in response to nasal suction)
Appearance (cyanosis)
Respiration
773
How would you distinguish between the two major causes of bleeding post 20-weeks gestation?
Placenta previa = painless bleeding
Abruptio placentae = painful bleeding, typically accomanied by uterine contractions and fetal distress.
774
What is the diagnosis for flu-like sympoms + enlarged cervical lymph nodes and splenomegaly? What is the causative virus?
Infectious mononucleosis caused by EBV
775
Differentiate between ITP and TTP
Idiopathic thrombocytopenic purpura, due to antibodies against platelet antigens causes isolated thrombocytopenia and petechia.
Thrombotic thrombocytopenic purpura due to antibodies against ADAMTS13 protease (vWF metalloproteinase). **FAT RN** Fever, maha, thrombocytopenia, renal failure and neurologic disturbance.
776
What paraneoplastic syndrome is associated with squamous-cell carcinoma? What is the classic presentation?
Hilar mass with cavitation, productive cough and weight loss; smoking.
Excess parathyroid hormone related peptide leading to hypercalcemia (stones, thrones, groans and psychiatric overtones).
777
When considering sympotms in an individual with substnace use disorder, what is it important not to forget?
Make sure that you rule out an organic cause for symptoms rather than focussing on a substance-use etiology
778
What drugs used to treat MI are contraindicated with recent cocaine use?
Beta-blockers (esp. nonselective), because of the incerase in norepinephrine due to cocaine leading to unopposed alpha effects = vasoconstriction
779
What are the indications for treatment of a suspected viral meningitis?
Supportive care & observation unless
1. Elderly / immunocompromised (treat for bacterial until CSF cultures back)
2. Signs of HSV infection (e.g. genital lesions or PCR tests)
780
Which drugs cause pulmonary fibrosis? How would you differentiate their presentations?
Bleomycin (typically weeks-months)
Busulan (at least 4 years post-treatment) and also associated with significant myelosuppression
781
What are ketoconazole and griseofulvin's effects on CYP450
Ketoconazole inhibits CYP450
Griseofulvin induces CYP450
782
What CNS tumor is associated with this histology?
Meningioma (benign tumor from arachnoid cells). Note the psammona bodies.
783
How would you differentiate between aortic stenosis due to congenital cause versus sclerosis / aquired cause?
Congenital bicuspid valve presents with calcifications typically by age 50.
784
What are the origins of the vertebral arteries?
Subclavian arteries.
785
Damage to which nerve leads to vocal cord paralysis? What is the embryological origin of this nerve?
The recurrent laryngeal nerve arising from the 6th pharyngeal arch.
786
What is the diagnosis in an AIDS patient with a single ring-enhancing lesion with CD20+ cells?
Primary CNS lymphoma due to EBV infection.
787
What are the causes of hyperprolactinemia?
prolactinoma, antipsychotic drugs such as dopamine antagonists
788
This patient presents with thrombocytopenia. What is the etiology?
Thrombotic thrombocytopenic purpura, due to antibodies against ADAMTS13 metalloproteinase
789
What is the expected findings on investigation for primary sclerosing cholangitis?
Positive p-ANCA, elevations and alkaline phosphatase
790
What investigations are expected to be abnormal in PCOS?
Glucose, high T, high LH:FSH ratio.
791
Differentiate between adenocarcinoma of the esophagus and laryngeal squamous cell carcinoma
Typical presentation is dysphagia and weight loss\
Adenocarcinoma of the esophagus commonly associated with chronic GERD & progression from Barrett's eso, smoking and obesity.
Laryngeal squamous cell carcinoma is associated with excessive tobacco + alcohol, horseness etc.
792
What are the 1st generation sulfonylureas? What side-effects do they have? What are they used for?
chlorpropamide & tolbutamide
Disulfiram like reaction, weight gain
Used to incr insulin secretion.
793
What is Leber hereditary optic neuropathy? What is the pattern of inheritance?
Progressive blindness in young adult men; may have movement disorders, arrhythmias, MS-like syndrome.
Mitochondrial inheritance
794
What is the differential for this blood smear?
Megaloblastic anemia (note hypersegmented neutrophyl) due to folate deficiency or B12 deficiency.
795
What is the diagnosis? What immunodeficiency worsens the disease?
Leprosy (M. leprae), with interferon-gamma deficiency.
796
What is the pathogen which is most likely to cause this infection? What is it called?
HPV 6 / 11
condyloma acuminata
797
What infections can chlamydia cause in the newborn?
pneumonia and bacterial conjunctivitis
798
How does a congenital toxoplasmosis in the neonate present?
chorioretinitis.
799
What type of hypersensitivity reaction is a transfusion reaction?
Type II (IgG antibodies cause complement lysis of RBCs)
800
In addition to the classic triad of conjunctivitis, urethritis and arthritis, what other symptom can accompany reactive arthritis?
Sacroiliitis
801
What investigations can be done to diagnose paroxysmal nocturnal hemoglobinuria? What defect causes the disease?
elevated urine hemosiderin;
Defect in the PIG-A glycosyl phosphatidylinositol (GPI) anchor leading to binding of CD55 / CD59 complement-inhibiting proteins -\> complement-mediated hemolysis.
802
What is the diagnosis based on this blood smear? What symptoms and labs would you expect?
AML (note auer rods).
Symptoms hematuria, diffuse petichiae, chest pain and SOB
Labs low platelets, high D-dimer, low fibrinogen (DIC)
803
What is the cause and symptoms of renal osteodystrophy?
CKD + dialysis leading to joint pain, bone pain and multiple fractures.
Due to reduced GFR leading to reduced phosphate excretion -\> hypocalcemia -\> PTH
As well low D3 due to reduced a1-hydroxylation of D2
804
What test is diagnostic of B12 deficiency, even in the absence of an elevation in MCV?
Methylmalonic acid elevation
805
What are the autoantibodies produced in Graves disease?
thyrotropin receptor stimulatory antibodies
806
What immunodeficiency is associated with mycobacterial infections?
IL-12 receptor deficiency (or defect in interferon signalling)
807
What lesion is classically assocaited with prosopagnosia?
Right inferior temporal lobe lesion
808
Where is the lesion in an upper homonymous quandrantanopia?
Lower devision of the geniculocalcarine tract (meyer loop) (contralateral)
809
What is the lesion in a right inferior quandrantanopia?
Superior division of the calcarine sulcus, contralateral
810
What is the etiology of autoimmune hemolytic anemia?
Complement binds to the Ch2 region (Fc) of IgG
811
What are the common side-effects of protease inhibitors (for HIV treatment)?
Fat redistribution, hyperlipidemia, hyperglycemia, nausea, diarrhea, nephropathy and hematuria.
812
What is this finding? What condition is it found in?
Lisch nodules, found in neurofibromatosis type 1
813
What does the NF-1 gene produce?
neurofibromin, a GTPase-activating protein that decreases Ras signalling
814
What are the characteristics of hunter syndrome? How do you differentiate it from hurler syndrome?
Pearly, papular skin eruptions, a deep hoarse voice, skeletal abnormalities, distended abdo and diarrhea.
Cornea clouding found only in hurler syndrome
815
What are the characteristics of Niemann-Pick syndrome?
Hepatosplenomegaly, foam cells, cherry-red macular spots
816
What differentiates congenitally acquired rubella from CMV?
Rubella: blueberry muffin rash, cataracts, hearning loss, PDA
CMVO IUGR, CNS damage with hearing/vision impairment, periventricular calcifications on CT, microcephaly and intellectual disability.
817
What is the pulmonary capillary wedge pressure?
Measures left atrial / left ventricular end-diastolic pressure. Not affected by lung pathology?
818
What is the differential for S3 vs S4?
S4 is diastolic HF including concentric LVH and AA amyloidosis (restrictive cardiomyopathy)
an S3 is found in dilated cardiomyopathy with systolic failure and **reduced ejection fraction.**
819
Which vaccines induce only humoral immunity?
**RIP a**lways
Rabies, Intramuscular Influenza, Polio (salk, not oral) and hep A
Due to use of killed/inactivated virus
820
What are the characteristics of the bacterium which causes rocky mountain spotted fever?
Rickettsia rickettsii is a gram-negative *obligate intracellular* cocobacillus, which is transmitted by tick bites.
821
What CNS tracts are affected by B12 deficiency?
Degeration of myelinated neurons in the dorsal columns, later corticospinal tracts and spinocerebellar tracts.
822
What is 2nd line therapy for patients with Alzheimer dementia who fail acetylcholinesterase inhibitors? What is the mech of action?
Memantine, an NMDA antagonist (prevents excitatory neurotox).
823
How do you calculate a 95% confindence interval for the mean in a normal distribution from SD?
CI = mean +/- Zx SEM
SEM = SD / sqrt(n)
824
What are the risk factors for peptic ulcer disease?
H pylori, NSAID use, smoking.
NOT nitrites
825
How do you differentiate between Parkonsons and normal pressure hydrocephalus?
PD has a narrow-based shuffling gait and NPH has a wide based magnetic gait.
other NPH symptoms include urinary incontinence and bradykinesia.
826
A direct hyperbilirubinemia in the absence of findings other that jaundice or scléral icterus is suggestive of what disease? What is the appearance of the liver?
Dubin-Johnson syndrome, black liver
827
How would you differentiate between chlamydia and gonorrhoea urethritis
Gonorrhoea has purulent discharge and is gram negative diplococci characterized by antegenically variable pili. Chlamydia does not gram stain and is an intercellular bacterium
828
What are the key symptoms of diffuse large B-cell lymphoma?
fatigue & weight loss with a splenic mass.
829
What is the mechanism of action of senna glycoside?
Increases peristalsis (stimulant laxative).
830
Describe the difference between direct and indirect Coombs tests.
Direct = mixing of fetal blood with anti-IgG antibodies to decect presence of maternal antibodies attached to fetal cells.
Indirect = mixing of known Rh+ve RBCs with maternal serum, followed by anti-IgG serum (detects presence of maternal anti RhD antibodies
831
What does the clock drawing test assess?
integration of multiple domains: orientation, comprehension, concentration, language, memory and visual-spatial awareness.
832
What immunotherapy can be used for renal cell carcinoma and metastatic melanoma?
Recombinant interleukin 2 (adesleukin) which stimulates NK cells.
833
What are the symptoms and treatment for serotonin syndrome?
3As:
Activity (clonus, hyperreflexia, hypertonia, tremor seizure)
Autonomic instability (hypertonia, diaphoresis and diarrhea)
Altered mental status
Treat with cyclohetadine.
834
How would you differentiate between a problem with sertoli cells or leydig cells in finding an etiology for infertility?
Sertoli cells produce androgen binding protein, so low ABP makes them the culprit along with low T in semen.
835
What substances stimulate the growth of hemangiomas?
Vascular endothelial growth factor (VEGF)
and Fibroblast Growth Factor (FGF)
836
What is the mechanism of antibiotic resistance of MRSA?
Production of a modified penicillin binding protein.
837
Identify the cells from this micrograph of cerebellum. What neurotransmitter do they secrete?
Purkinje cells
Inhibitory -- secrete GABA
838
What are risk factors for AAA?
Smoking, atherosclerosis, older age, male, FH.
839
Levels of what substance would be increased in serum in megaloblastic anemia? Why?
Homocysteine (due to impaired conversion of homocysteine to methionine).
840
exposures to which pathogens warrant use of passive immunization for postexposure prophylaxis?
Tetanus, botulism, hep B, varicella, rabies
“To Be Healed Very Rapidly"
841
What is the difference between oppositional defiant disorder and conduct disorder?
ODD manifests as disobediance towards authority in the absence of serious violations of societal norms, e.g. aggression towards people and animals, destruction of property, deceitfulness/theft, serious rule violations.
842
What symptoms are typically associated with hemolytic-uremic syndrome? What bacteria are most commonly associated? What is the virulence factor?
Symptoms: thrombocytopenia, microangiopathic hemolytic anemia, AKI
Bacteria: shigella and E.coli O157:H7
Virulence: Shiga-toxin which inactivates ribosomes, leading to cell death (B binds cells and lets A (toxic) in.)
843
What is the Charcot triad of cholangitis? What might you see on labs?
RUQ pain, jaundice, fever.
inv: leukocytosis + neutrophilia
844
What carcinoma would present with a neck mass which moves with swallowing and hypocalcemia?
Medullary carcinoma of the thyroid
845
What is the infectious organism that is responsible for this rash? What is the risk factor for transmission?
N. meningitidis causing meningococcemia.
Often transmitted in close quarters.
846
How do you distinguish between delayed sleep-wake phase disorder and insomnia?
Pts with insomnia typically have trouble falling asleep regardless of designated sleep time and often awaken in the middle of the night. With DSWPD, they can fall asleep at their desired sleep time; it's more that there is a misalignment.
847
What is the acronym for the derivatives of the pharyngeal arches?
When at the restaurant of the golden arches, children tend to **chew,** then **smile,** then **swallow styl**ishly, or **simply swallow**, and then **speak**.
1. Chew - maxillary, mandibular processes, malleus/incus, muscles of mastication
2. Smile - stapes / styloid, lessor horn of hyoid, muscles of facial expression'
3. Swallow stylishly - greater horn of hyoid and stylopharyngeus
4. Aretynoids, cricoid, corniculate, cuneiform, thyroid, pharyngeal constrictors, cricothyorid, levator veli palatini
5. speak - Intrisic muscles of larynx except cricothyroid
848
Which chemotherapeutic agents are cell-cycle nonspecific?
Cisplatin / Pt agents
Alkylating agents: busulfran, cyclophosphamide, ifosfamide, nitrosoureas
849
Differentiat between the symptoms typical of lesions of the cerebrocerebellum, vestibulocerebellum, or spinocerebellum.
Cerebrocerebellum: ipsilateral symptoms including dysdiadochokinesia and intention tremor.
Vestibulocerebellum, saccades / eye movements, posture, balance
Spinocerebellum, truncal ataxia
850
What is the difference between rivastigmine and pyridostigmine?
Both are acetylcholinesterase inhibitors, however
Rivastigmine is used for dementia and is active in the CNS
Pyridostigmine is active in the PNS and can be used for myasthenia gravis treatment
851
How would you differentiate between Hirschprung disease and imperforate anus in a newborn?
Rectal exam; Hirschprung gives a "squirt sign" which is forceful expulsion of stool on rectal exam, whereas you'll see rectal distension in anal atresia.
852
What are the symptoms of strongyloidiasis?
Eosinophilia (typical of parasitic infections), larva currens (mobile erythematus urticarial plaques), with cough and diarrhea.
853
A thin blue line under the gums suggests what condition?
Lead poisoning
854
Mixed LMN and UMN signs without sensory defecits is concerning for what condition? What is the location of the lesions?
ALS - amyotrophic lateral sclerosis
Typically presents with LMN first due to degeneration of anterior horn cells, followed by UMN due to degeneration of corticospinal tracts.
855
What does this bowel CT scan show? What other symptoms would you expect?
Bowel thickening with pericolic fat staining, suggestive of diverticulitis due to microperforation of a diverticulum.
Other symptoms include a tender mass int he LLQ, worsening cramping pain, fever, nausea, constipation.
856
What aditional layer of skin is present on the palms of hands and the soles of the feet and the dorsal distal phalanges?
Glabrous skin has a stratum lucidum.
857
How does norepinephrine affect conduction velocity in the AV node and His-Purkinje system?
beta-1 adrenergic receptors -\> increased Ca2+ influx into cells, reducing potential required for depolarization.
858
What signs and symptoms are characteristic of psoas abcess? What is the most common organism involved? What are risk factors?
diffuse righ hip pain that gets better in a supine position with a flexed knee.
Most commonly caused by staph aureus
Risk factors include immunosuppression, secondary infection, recent surgery.
859
What serum abnormality can be caused by long-term PPI usage?
hypomagnesemia
860
What is the differential for these inclusions?
These are lewy bodies, found in Lewy body dementia and Parkinson disease.
861
What prophylaxis can be offered to patients at risk of developing colon cancer?
Daily aspriin (which inhibits COX-2).
862
how does the HSV1 virus reactivate?
Via travel from the cell body to axons via kinesin-dependent anterograde transport
863
What is the preferred antidote for beta-blocker overdose? How does it work?
Glucagon, increases intracellular cAMP and increases Ca2+ release with muscle contraction.
864
What side effect is associated with zidovudine?
anemia
865
What is the inheritance pattern of neurofibromatosis type II?
Autosomal dominant
866
What virus causes this common childhood lesion? What family does it belong to?
This is molluscum contagiosum, a poxvirus
867
What bacteria can be visualized by Ziehl-Neelsen stain?
TB - mycobacterium tuberculosis
868
What is the causative organism on this slide? What symptoms are expected?
Histoplasmosis caused by histoplasma capsulatum; common presentation is productive cough with green sputum, fever, headache, general malaise in someone who has exposure to contaminated soil with bird/bat droppings (ohio/mississippi valleys)
869
What is Lidde syndrome? How do you treat it? What is the inheritance?
Due to GoF mutation leading to decreased ENaC degredation, increased Na+ resorption + *hypoaldosteronism*. Treat with triamterene or amiloride.
Inheritance is autosomal dominant
870
An EFTS with low AFP, beta-HCG, Estriol, and normal Inhibin A indicates which genetic disorder?
Trisomy 18; Edwards
871
What is the AFP pattern most concerning for Down Syndrome?
Low AFP, high betaHCG, low estriol, high inhibin A
872
Which enzyme is most active with respect to glucose metabolism in the fasted state
fructose bisphosphatase 2
873
An isolated low beta-HCG with normal other EFTS raises suspiscion for...
Trisomy 13, patau syndrome
874
Which TCA metabolite is responsible for inhibiting phosphofructokinase and activating acetyl-CoA carboxylase? What is the net effect?
Citrate; decreased glycolysis and increased lipid synthesis
875
What is the classification of a virus which causes koilocytes in tissue and genital warts?
Double-stranded, non-enveloped circular DNA virus; HPV.
876
What is the inheritance pattern of von Willebrand disease? What shows up on labs? How do you treat it?
Autosomal dominant. On labs, increased bleeding and PTT time. Traet with desmopressin
877
What are the monoamine oxidase inhibitors?
Tranylcypromine, phenelzine, isocarboxazid, selegiline (selective MAO-B)
MAO **T**akes **P**ride **I**n **S**hanghai
878
What is this finding from kidney biopsy stained with PAS? What other symptoms would you expect?
Crescentic glomerulonephritis, seen in Goodpasture syndrome. Cross-reactivity with resp. membranes leads to hemoptysis, anemia, and hematuria
879
What is the organism on this silver-stained mucous membrane biopsy? What is the treatment?
Mucor (wide-branching nonseptate hyphae), treat with amphotericin B
880
What is flucytosine used for?
Cryptococcal meningitis (in combination with amphotericin B) and candida infenctions.
881
What is the typical presentation of phencyclidine use?
How is this differentiated from amphetamine use?
Agression, HTN, tachy, fever, horizontal nystagmus and hyperacusis
Amphetamines would present with pupilary dilatation.
882
How do ACE inhibitors protect the kidney?
Reduction of ATII resulting in vasodilation preferentially of the efferent arteriole, reducing glomerular pressure.
883
What treatment regimen is indicated for large B-cell lyphoma of limited stage?
R-CHOP
Rituximab + cyclophosphamide, doxorubiin, vincristine (oncovin), and prednisone
884
Which prostate zone are most cancers found in?
The peripheral zone, adjacent to the rectum
885
Describe the lesion. What is it most commonly associated with?
Punched-out soltary lesions with underlying tissues replaced by chronic inflammatory cells; characteristic of H. Pylori.
886
What is winters formula for compensation for metabolic acidosis?
Predicted PCO2 = 1.5 x HCO3 + 8
887
What treatment could you give for salicylate overdose?
How does it work?
Bicarbonate
Alkalinizes urine, thus promoting deprotonation of acidic drugs and favouring excretion
888
Describe how the JVP corresponds to the cardiac cycle (see image)
a - atrial contraction
c - RV contraction
x - displacement of tricuspid down during ventricular ejection
v - filling of RA against closed tricuspid valve
y - RA emptying into RV
889
What is a gluteus maximus gait? Damage to which nerve would most likely produce it?
Hips level, leaning back slightly with heel strike.
Inferior gluteal nerve
890
How would you differentiate between tabes dorsalis and vitamin B12 deficiency?
B12 deficiency produces combination motor *and* sensory findings.
Tabes is also accompanied by other symptoms of neurosyphilis including overflow incontinence, lower extremity pain, Argyl Robertson pupill, sensory ataxia.
891
How would you differentiate between *H ducreyi* and *C trachomatis* L1-L3 serotype infection?
chlamydia trachomatis type L1-L3 presents initially with a painless ulcer then regional lymphadenitis which is painful.
Ducreyi is going to present with a painful papule -\> pustule -\> ulcer ++lymphadenitis.
NO urethral discharge for either
892
What is the diagnosis?
Paget disease of breast
893
What risk factor and symptoms should raise suspiscion for prion disease?
Rapid progression of dementia + startle response and myoclonus.
Risk factors include cadaveric pituitary hormone, ingestion of infected brain tissue, dural, corneal and liver transplants.
894
What is the effect of Milrinone? What is the mechanism of action?
Increased cardiac contractility and decreased peripheral vascular resitance
PDE-3 inhibitor
895
In PKU, what neurotransmitter is affected?
Dopamine
896
Name the class of drugs associated with letters B, C, and D
B - cholestyramine
C - HMG-CoA inhibitors
D - Fibrates e.g. gemfibrozil
897
Describe the sensory distribustion of C2
posterior half of skull
898
Describe the sensory distribution of C3
Turtleneck shirt.
899
Describe the C4 dermatome
a low-collar shirt
900
What is the pharyngeal arch which is associated with the intrinsic laryngeal muscles (except cricothyroid), artenoids and corniculate cartilage?
The 6th pharyngeal arch
901
What is the age distribution for Hodgkin lymphoma? Non-hodgkin lymphoma?
Hodgkin lymphoma is typically 20-40yo
Non-Hodgkin is typically 65+
902
Describe the arterial supply of the esophagus
Proximal 1/3 - inferior thyroid a
middle 1/3 bronchial artery + thoracic aorta
bottom 1/3 left gastric artery
903
Identify the pathogen. How is it transmitted?
Leishmania donovi transmitted by the sandfly
904
What are the symptoms and treatment of visceral leishmaniasis?
Symptoms: "black disease", hepatosplenomegaly, malaise, pancytopenia, weight loss
treatment: sodium stibogluconate
905
What is the first line treatment for Staph aureus?
1st gen cephalosporin e.g. cefazolin or dicloxacilin, oxacilin or nafcilin
906
What is the mechanism of action and major side effect of chlormaphenicol?
Binding to 50S subunit; can cause grey baby syndrome and reversible bone marrow suppression
907
Which polio vaccine is live attenuated? Which is killed?
Live attenuated is Sabin (oral)
Killed is Salk IM
908
What are the key changes relative to point C that would produce A, B, D, or E?
A - Increased venous return (lower resistance) AND increased inotropy
B - Increased inotropy w/o change in venous return (e.g. digoxin, catecholamines (beta-1 agonist))
D - Negative inotropy due to narcotic overdose, beta-blockers, CCBs, dilated cardiomyopathy
E - increased total peripheral resistance (phenylephrine
909
How would you differentiate between hunter/hurler syndrome and I-cell disease? What are the substances that accumulate in the former
Hunter (iduronate sulfatase) and hurler (a-L-iduronase) = glycosaminoglycans; urine mucoplysaccharides
I-cell disease = inclusion bodies and membrane-bound vacuoles, elevated serum lysosomal enzymes, affects fibroblasts
910
What is appropriate renal testing for diabetic neuropathy?
urinary albumin excretion, as creatinine is only decreased in mid-late diseae
911
What is the classic presentation of polyarteritis nodosa? What is the histologic appearance?
Fever, weight loss, myalgias, arthralgias, abdo pain, hypertension; elevations in ESR/CRP, leukocytosis
Fibrinoid necrosis of medium-sized muscular arteries.
912
What syndrome would include tachycardia, hyperthermia, mydriasis, hyperreflexia and clonus? What drugs would cause it?
Serotonin syndrome
SSRI/SNRI, TCAs, MAO inhibitors
Triptans, tramadol, odansetron, linezolid, MDMA, dextromethorphan, meperidine, St. John's Wort
913
What is the key serum electrolyte disturbances in acute pancreatitis? What signs clinically would be suggestive of it?
Hypocalcemia; Chvostek or Trousseau sign
914
How would you differentiate borrelia recurrentis infection from Brucella?
Borellia recurrentis has a **relapsing fever that lasts 3-5 days with 7-9 day breaks** in between and presents with jaundice, ecchymoses, change in LOC, neurologic findings, resp distress
Brucella - think unpastreurized dairy, **undulant fever** which is higher during the day and better at night, night sweats, weight loss, myalgias and arthralgias
915
What is the characteristic urinary side effect of lithium toxicity?
Nephrogenic DI; low urine specific gravity (\<1.01) and low osmolarity (\<200mOsm/Kg) which is not corrected by ADH/vasopressin.
916
What are the serum disturbances that would be expected in tumor lysis syndrome. How can you address/prevent them?
High potassium, phosphate and purines -\> uric acid
Give rasburicase or allopurinol (NOT probenecid, you don't want renal excretion from gout)
Hyperphosphatemia -\> hypocalcemia, so may require additl Ca++
917
What is the etiology of william syndrome?
Microdeletion of long-arm of chromosome 7
918
What is the most likely etiology for someone presenting with back pain and this CXR?
Note cavitary lesion at lung apex -\> TB
so Pott disease of spine
919
If you have an erythema surrounding a catheter site and systemic infection, what is the most likely bug?
Staphylococcus epidermidis (coag neg staph)
920
What are the urease-positive organisms?
Proteus, Cryptococcus, H pylori, Ureaplasma, Nocardia, Klebsiella, Staph epidermidis and saprophyticus
Pee CHUNKS
921
Which enzyme is impaired in prolonged or high-dose nitroprusside treatment?
mitochondrial cytochrome C oxidase due to cyanide toxicity
922
Which other cancers are pheochromocytomas associated with?
MEN2A - medulalary carcinoma of thyroid and parathyroid hyperplasia
MEN2B - medullary thyroid carcionma, mucosal neuromas, marfinoid habitus
923
What is the difference in the mechanism of action of aminoglycosides and tetracyclines?
Aminoglycosides = irreversible binding to 30S subunit
Tetracyclines = reversible binding of 30S subunit (i.e. bacteriostatic vs bactericidal)
924
How would you differentiate between hereditary spherocytosis and AIHA?
Hereditary spherocytosis tends to present with increased MCHC, AIHA may present with other cytopenias, or AIHA-adjacent conditions like SLE
925
What interferon is useful for treating relapsing MS?
Beta-interferon
926
What is interleukin-11 used for?
Treatment of thrombocytopenia
927
What is the effect of norepinephrine on the heart?
Vasoconstriction -\> increased diastolic filling -\> increased CO, reflex bradycardia
928
What is the characteristic x-ray of a giant cell tumor?
expansile osteolytic and radiolucent with sharp borders found in the distal epiphysis.
929
What is the most common outcome of acute hep B infection? What are risk factors for chronic disease?
Immune clearance
Risk factors: \<5 yo, immunosuppression.
930
What is the most common complication of CMV retinitis?
Retinal detachment
931
What diseases are due to frameshift mutations?
Duchenne muscular dystrophy and Tay-Sachs
932
933
Milky white blood is due to what deficiency? What is the causative substance?
What does it commonly present with?
Lipoprotein lipase defiency causing familial hyperchylomicronemia.
Acute pancreatitis
934
When do the primitive reflexes disappear?
moro - 3 mos
root - 4 mos
palmar grasp - 6 mos
babinski - 24 mos
935
What is a latent error?
Due to conditions of a healthcare setting that are "accidents waiting to happen"
936
How would you differentiate between CAH due to 11-beta-hydroxylase vs 21-hydroxylase deficiency?
11-beta-hydroxylase deficiency results in 11-deoxcortisone overproduction -\> HTN (due to mineralocorticoid effects)
21-hydroxylase deficiency presents with hypotension due to lack of mineralocorticoid production
937
What are the cells that are activated 3-5 days post ischemic damage of CNS? 1-2 weeks?
3-5 days = activated microglia
1-2 weeks = activated astrocytes form glial scar and secrete GFAP
938
What organisms produce large liver cysts that are hypoechoic with a calcified rim? What are these cysts called?
tapeworm: Echinococcus granulosus
Hydatid cysts
939
How would you distinguish between anorexia nervosa with bingeing and purging and bulemia nervosa?
Anorexia typically presents with v. low BMI vs bulemia which tends to present with either normal or elevated BMI
940
What anticancer drug inhibits topoisomerase II? What is it commonly used for? What are the side effects?
Etoposide, small cell lung cencer, prosate cancer, refractory testicular carcinoma
Side effects: alopecia and myelosuppression
941
What is the diagnosis based on this kidney biopsy of a patient with SLE?
Membranous nephropathy
942
What asthma therapy interacts with these cells?
Mast cells - cromolyn sodium prevents degranulation.
943
What disorder results in assigned female appearance at birth with XY genotype and normal levels of testosterone, estrogen and LH?
5-alpha reductase deficiency
944
What condition may cause polyhydramnios in utero? What is the appearance on X-ray? What is the associated syndrome?
Tracheoesophageal fistula
Gastric air bubble on x-ray
VACTERL
Vertebral abnormalities, Anal atresia, Cardiac defects, TE fistula, Renal & gu abnormalities, Limb defects
945
What do you do when a patient gives a comment on your youthful appearance?
Acknowledge it / thank them for the compliment.
946
What is the only detectable sign of HBV infection during the window period? Why?
HBcAb
Due to the fact that HBsAg is being bound by HBsAb, but there is not enough HBsAb remaining unbound for it to be detectable
947
What does alpha-amanitin block?
RNA pol II and III; causing decreased heterogenous nuclear RNA which normally is processed into mRNA
948
What is the immediate change in hormone concentrtion that occurs due to starting a combined OCP?
progesterone -\> negative feedback on GnRH -\> less FSH which inhibits follicular growth and reduces estrogen concentration -\> no positive LH feedback, no LH surge & no ovulation
949
What type of anemia is indicated by the presence of target cells?
Thalassemia
950
What is the anemia characteristic of sickle cell disease?
Normocytic, increased RDW, low red cells
951
What are the first two (irreversible) steps in gluconeogenesis?
Pyruvate to oxaloacetate via pyruvate carboxylase
oxaloacetate to phosphoenolpyruvate via PEP carboxylase
952
What organ is responsible for secreting HCO3- to neutralize stomach acid?
Exocrine pancreas
