? Flashcards
Enzymes that obligate anaerobes lack?
superoxide dismutase (converts superoxide radicals into hydrogen peroxide)
catalase
(converts hydrogen peroxide into water and oxygen gas)
Drugs that can prolong QT?
Sotalol (beta blocker) Risperidone (antipsychotics) Macrolides Chloroquine Protease inhibitors (-navir) Quinidine (class Ia; also class III) Thiazides
[Some Risky Meds Can Prolong QT]
and lead to torsades de pointes (polymorphic ventricular tachycardia)
hypokalemia
hypomagnesemia
(check electrolytes! IV admin if necessary)
Patient with craving for ice chips, weakness, pallor, tachycardia, with history of chronic hemorrhoids?
iron deficiency anemia
pica - craving of nonfood substances like ice chips
Antidote for digoxin toxicity?
Digoxin immune Fab
Bicornuate uterus results from what process?
results from INCOMPLETE fusion of the paramesonephric/Müllerian ducts.
Can lead to anatomic defects, leading to recurrent miscarriages.
also called a “heart-shaped” uterus - composed of two “horns” separated by a septum
(Complete failure of fusion leads to double uterus and vagina.)
Hyatidiform mole is the most common precursor of what ovarian germ tumor? What tumor marker is monitored after D&C of mole?
Choriocarcinoma (malignant tumor composed of cytotrophoblasts and syncytiotrophoblasts – mimics placental tissue but villi are absent)
Monitor hCG levels to ensure adequate mole removal and screen for choriocarcinoma development.
Two pathways of choriocarcinoma:
- germ cell tumor (NO association with gestation; poor chemo response)
- complication of pregnancy/gestation (molar pregnancy, spontaneous abortion, post-normal pregnancy; responds well to chemo)
Polymorphic V-tach, shifting sinusoidal waveform, variable amplitude V-tach?
torsades de pointes
MRI vs. CT?
MRI - no ionizing, visualize soft tissues, caution with metal, bone is GRAY
CT - ionizing radiation, bone detail, recognition of blood, bone is WHITE
What structures arise from the paramesonephric ducts? What’s another name for these ducts?
Müllerian ducts:
- Fallopian tubes
- Uterus
- Upper portion of vagina
Definition of first-degree heart block? Symptoms?
prolonged PR interval >200ms (five little boxes/one big box), asymptomatic
IgG autoantibodies against desmosomes? Difference between desmosome and hemidesmosomes?
Desmosome - keratin interactions between cells
Autoantibodies result in pemphigus vulgaris
Hemidesmosome - keratin in basal cells connected to underlying BM
Autoantibodies result in bullous pemphigoid
Delirium vs. dementia?
Delirium - acute onset of “waxing and waning” level of consciousness; usually secondary to acute illness and usually reversible
Dementia - gradual/slow decline in intellectual ability or “cognition” without affecting consciousness
NOT associated with acute illness, usually irreversible
18yo delayed onset of puberty, small penis/testicles, lack of facial, pubic, and underarm hair; also no sense of smell (anosmia)?
Kallmann syndrome
defective migration of GnRH cells and formation of olfactory bulb
decreased GnRH synthesis in hypothalamus, decreased GnRH, FSH, LH, testosterone, sperm count
Blood flow into thyroid? out of thyroid?
Flow IN:
- superior thyroid artery from external carotid
- inferior thyroid artery from thyrocervical trunk
Flow OUT:
- superior thyroid vein
- middle thyroid vein
- inferior thyroid vein
Lesion of what causes coma?
Reticular activating system of midbrain
What is Virchow’s triad? Homan’s sign?
Virchow’s triad: stasis, hypercoaguability, endothelial damage
Homan’s sign: calf pain upon dorsiflexion of foot
What enzyme catalyzes the rate-limiting step of cholesterol synthesis? What class of drugs inhibits this enzyme?
HMG-CoA reductase, inhibited by statins
Where does benign prostatic hyperplasia arise from in the prostate? Where does prostatic adenocarcinoma usually arise from?
BPH characterized by smooth, elastic, firm nodular enlargement of the periurethral (lateral and middle) lobes.
smooth, symmetric, enlarged
Adenocarcinoma usually arises from the posterior lobe (peripheral zone) of the prostate gland.
asymmetric, hard nodule
Which adrenergic antagonists are used to treat HTN as well as urinary retention in pts with benign prostatic hyperplasia?
alpha1-antagonists (terazosin and tamsulosin) cause relaxation of the smooth muscle
What is the difference between agenesis and aplasia? What is oligohydraminos due to?
Agenesis - absent organ due to absent primordial tissue
Aplasia - absent organ despite presence of primordial tissue
Hypoplasia - incomplete organ development; primordial tissue present
What cancers produce EPO as their paraneoplastic syndrome?
renal cell carcinoman
hemangioblastoma
hepatocellular carcinoma
pheochromocytoma
ADH paraneoplastic sydnrome?
small cell lung cancer
intracranial neoplasms
Complement deficiency associated with: Neisseiria? frequent pyogenic resp. infections? paroxysmal nocturnal hematuria? type III sensitivity?
Neisseiria: C5-C9
pyogenic: C3
PNH: CD55 or 59 - decay accelerating factor
increased frequency of type III sensitivity (glomerulonephritis): C3
Pt can’t extend the wrist for 3 days, fell asleep with arm draped over chair 4 days ago - what does he have?
Radial nerve neuropathy - Saturday night palsy
Does regeneration happen in the CNS? PNS?
Schwann cells secrete growth factor that allows regeneration; oligodendrocytes secrete inhibitory factor
1-2mm per day growth in the PNS
Pt with “skip” lesions (discontinuous areas of focal narrowing) and “string” sign (significant narrowing) in the terminal ileum? Treatment?
Crohn’s disease
also transmural inflammation and cobblestone appearance
Treatment:
- 5-ASA (salicylates)
- glucocorticoids
- azathioprine
- 6MP
- infliximab, adilumab
Night terrors, sleepwalking, enuresis phase of sleep? Treatment?
Stage N3 (delta waves)
Benzodiazapenes get rid of this stage!
What causes traveller’s diarrhea?
ETEC (E. Coli) - watery diarrhea!!
2’s of Meckel’s diverticulum?
- 2 inches long
- within 2 feet of the ileocecal valve
- 2% of the population
- presents in first 2 years of life
Most common renal malignancy? Associated gene deletion?
Renal cell carcinoma
(presents as flank pain, palpable flank mass, hematuria)
Gene deletion on chromosome 3 (sporadic or inherited as von Hippel-Lindau syndrome)
What does the Eustachian (auditory) tube connect? Purpose? Treatment for dysfunction?
Connects middle ear to nasopharynx - makes pressure in middle ear same as atm. pressure
Intranasal steroids
Pediatric pt with right flank mass and blood in urine - what is the most likely malignancy? Genetic association? What is the WAGR complex?
Wilms’ tumor (nephroblastoma)
Deletion of WT1 tumor suppressor gene on chromosome 11
WAGR complex Wilms' tumor Aniridia (absence of the iris in the eye) Genitourinary malformation mental Retardation
What is Kartagener’s syndrome?
Primary ciliary dyskinesia - immotile cilia due to dynein arm defect
- male infertility (immotile sperm), decreased female fertility
- bronchiectasis
- recurrent sinusitis (bacterial and particles not pushed out)
- associated with situs inversus
What cardiomyopathy are amyloidosis and sarcoidosis associated with? Other diseases or conditions associated?
Restrictive/obliterative cardiomyopathy (diastolic dysfunction ensues)
also:
- postradiation fibrosis
- endocardial fibroelastosis (thick fibroelastic tissue in endocardium of young children)
- Loffler’s syndrome (endomyocardial fibrosis with prominent eosinophilic infiltrate)
- hemochromatosis (dilated cardiomyopathy can also occur)
Primary vs. secondary hyperaldosteronism?
Primary - low renin, caused by adrenal hyperplasia or aldosterone-secreting adrenal adenoma (Conn’s syndrome)
Treatment is to surgically remove the tumor and/or spironolactone, a potassium-sparing diuretic that works as an aldosterone antagonist.
Secondary - high renin, due to renal perception of low intravascular volume resulting in an overactive renin-angiotensin system
Treatment is spironolactone.
What mutation is associated with Hirschprung’s disease?
RET gene mutation
Treatment of acute gout vs. chronic gout?
Acute: NSAIDs (indomethacin), glucocorticoids (prednisone), colchicine
Chronic: xanthine oxidase inhibitors (allopurinol, febuxostat)
Structures found under and just inferior to the inguinal ligament? List them in order from lateral to medial.
NAVEL
nerve, artery, vein, empty space, lymphatics
femoral nerve, femoral artery, femoral vein, empty space, lymphatics
Sertoli cells release what substance on the paramesonephric ducts in a normal male fetus? What do Leydig cells do?
Mullerian inhibitory factor (MIF)
suppresses development of the paramesonephric ducts (Fallopian tubes, uterus, upper portion of vagina)
Leydig cells secrete androgens that sitmulate development of mesonephric ducts (Wolffian ducts; male internal structures)
Seminal vesicles, epididymis, ejaculatory duct, and ductus deferens (SEED)
Mechanism of action of methyphenidate?
CNS stimulant that increases catecholamines at the synaptic cleft (especially NE and dopamine)
Indirect sympathomimetic that releases stored catecholamines
Ritalin - used for ADHD, narcolepsy, appetite control
Signs of amphetamine intoxication?
euphoria grandiosity pupillary dilation prolonged wakefulness and attention hypertension tachycardia anorexia paranoia fever
SEVERE: cardiac arrest and seizure
What medication targets CD3 and is used to prevent acute transplant rejection?
Muromonab-CD3 (OKT3)
What does allopurinol do in chronic gout? Probenacid?
Allopurinol (xanthine oxidase inhibitor)
inhibits production of uric acid
Never start during an acute attack - it can make gout worse!
Probenecid
increases excretion of uric acid
Most common lung cancer seen in asbestosis? Most common lung cancer seen in nonsmokers?
Bronchogenic adenocarcinoma!
Endocarditis organisms? What if nothing on culture?
Staph aureus (30%)
Viridans strep (including Strep mutans; 20-30%)
Enterococci (10%)
Coagulase-negative Staph (Staph epidermiditis; 5-10%)
If not showing up on culture, HACEK organisms!!
Lymphoma that looks like CLL without as many constitutional symptoms?
Small lymphocytic lymphoma
Most common organism causing lobar pneumonia? What about walking pneumonia?
Strep. pneumonia
Myoplasma
Chlamydophila
Legionella
or VIRAL
Signs of right sided heart failure? Left sided heart failure?
Right sided:
JVD
peripheral edema
hepatic congestion/nutmeg liver (painful!)
Left sided:
pulmonary edema – dyspnea on exertion
orthopnea
paroxysmal nocturnal dyspnea
What is first-line in ADHD?
Methylphenidate (Ritalin, Concerta)
Dextroamphetamine (Adderall)
increases catecholamines
Selective NE reuptake inhibitor:
Atomoxetine (Strattera)
How many umbilical vessels? Which most highly oxygenated?
2 umbilical arteries (go into fetal internal iliac arteries)
1 umbilical vein (dumps into fetal IVC) - oxygenated blood
Abnormal lab values leading you to think alcoholic hepatitis?
AST > ALT (usually greater than 2:1 ratio)
“A Scotch and Tonic”
What embryological derivative does the PNS come from?
Neural crest (derived from ectoderm)
What complement protein is an opsonin? Which complement protein aids in neutrophil chemotaxis? Which form the MAC?
C3b - opsonin (binds to pathogen so can be phagocytosed, also IgG)
C5a - neutrophil chemotaxis
C5b-9 - MAC
Why are ACE inhibitors contraindicated in pregnancy? What centrally acting alpha2-agonist is often used to treat HTN in pregnancy?
teratogenic (cardiac, CNS in 1st tri.; renal malformations in 2and3)
also seen with angiotensinII inhibitors (ARBs)
alpha-methyldopa
Crescent-shaped radiopacity in CT of head that crosses suture lines? Which vessels are involved?
Subdural hematoma, rupture of bridging veins
slow venous bleeding (less pressure), so hematoma develops over time
How to differentiate between gout and pseudogout upon exam of synovial fluid aspirate? What is the difference?
Gout - crystals are yellow when parallel to light
Pseudogout - crystals are blue when parallel to light
Gout crystals: monosodium urate, needle-shaped, negative birefring.
Pseudogout crystals: calcium pyrophosphate, rhomboid, basophilic, weakly positive birefringence (blue when parallel to light, yellow when perpendicular)
Child with nephritis, deafness, ocular dysfunction - diagnosis?
Inheritance? Mechanism?
Alport syndrome (defect in type IV collagen) "can't see, can't pee, can't hear me"
most common form is X-linked recessive
type IV collagen is an important structural component of the BM of the kidney, ears, and eyes
What type of collagen organizes bone, skin, and tendons? What type of collagen organizes cartilage? Defect in former causes what disease?
Type I collagen - bone, skin, tendons (most common)
Type II collagen - cartilage
Defect in Type I results in osteogenesis imperfecta.
Composition of a nucleosome? What are common AAs? Which histone ties nucleosomes together?
negatively charged DNA wrapped around positively charged histone octomer (H2A, H2B, H3, H4 x 2 each)
lots of Lys and Arg
H1 is the only histone that is not in the nucleosome core - it ties nucleosomes together.
Test used to confirm diagnosis of hereditary spherocytosis? What findings are associated with this disease? Treatment?
osmotic fragility test - RBCs incubated in increasingly hypotonic saline and Hb release monitored (spherocytes lyse more easily than normal)
Findings:
- splenomegaly, jaundice/gallstone, aplastic crisis (ParvoB19 infection)
- small round RBCs with no central pallor due to less membrane
- increased MCHC due to membrane loss and cell dehydration
MCHC (ratio of Hb to volume of RBCs - lower since smaller RBCs)
- increased red cell distribution width
- premature removal of RBCs by spleen as the result of the above
Treatment: splenectomy
At what positive G force does visual “black-out” occur? Why?
4-6G
G forces pool blood into abdomen and legs, insufficient return to heart and to brain
Defect in hereditary spherocytosis?
defect in RBC cytoskeleton proteins
- spectrin
- band 3
- protein 4.2
- ankyrin
What makes the CSF? Function?
choroid plexus of the lateral ventricles
- support/cushion
- electrolytes and pH maintenance
- medium for transfer of messages
3yo pt with 3-day fever (102F), fourth day developed a red macular rash over entire trunk and fever resolves abruptly. What viral infection?
Roseola
very high fevers, diffuse macular rash and fever goes away
Mechanism of action of strychnine? Tetanus toxin? Black widow spider toxin? Botulinum toxin? Alpha-bungarotoxin?
Strychnine - glycine antagonist (glycine = inhibitory NT in the spinal cord; causes a lot of activation - bronchospasms and asphyxia)
Tetanus - block inhibitory function of glycine and GABA (bind Rinshaw cells)
Black widow spider toxin - causes excessive release of ACh (muscle pain and cramping)
Botulinum - inhibits release of ACh at the NMJ (flaccid paralysis)
Alpha-bungarotoxin - binds to postsynaptic nicotinic ACh receptors at the NMJ (flaccid paralysis; venom of a Chinese snake!)
What phase of metabolism do geriatric patients lose first? Which phase makes a slightly polar metabolism by ox., red., or hydrolysis?
Geriatric pts lose Phase I first catalyzed by cytochrome P450
Phase I = oxidation, reduction, and hydrolysis
Difference between malingering and factitious disorder?
Malingering - faking symptoms/complaints in order to gain something (get out of work, drug seeking, attention)
Factitious disorder - claims illness without any secondary gain (enjoys being the pt/sick role)
What cancers cause the paraneoplastic syndrome Lambert-Eaton syndrome?
Small cell carcinoma
also Hodgkin lymphoma and malignant thymoma
Lambert-Eaton - antibodies bind presynaptic voltage-gated Ca2+ channels at the NMJ
prevent Ca2+ channels from opening so cause muscle weakness
Pt with intense third and profuse urination - suspect diabetes insipidus. What urine specific gravity and serum osmolality findings would you see?
Urine specific gravity < 1.006 (LOW)
dilute urine - low urine osmolality
Serum osmolality high
concentrated serum
Most common tumor of urinary tract? Usual presenting complaint of pt with this tumor? What substance exposures increase risk of this tumor?
Transitional cell carcinoma
painless hematuria
- phenacetin
- smoking
- aniline dyes
- cyclophosphamide
Conductive hearing loss? Causes?
sound not being conducted
nerves working, but sound isn’t being transmitted to cochlear apparatus
- wax build-up
- ear infection (otitis externa or media)
- ruptured tympanic membrane
- otosclerosis (malformation of ossicles of middle ear)
(other type is sensoneural hearing loss - nerves not working well)
Conditions associated with oligohydramnios? Conditions associated with polyhydramnios? What is Potter syndrome?
Oligo - decreased fetal urine production
- placental insuff
- bilateral renal agenesis
- posterior urethral valves (males)
Poly - can’t swallow
- esophageal or duodenal atresia
- anencephaly
Potter syndrome - bilateral renal agenesis, oligohydramnios Pulmonary hypoplasia Oligohydramnios Twisted skin Twisted face Extremity/limb deformation Renal agenesis
What pulmonary artery pressures indicate pulmonary HTN?
Normal: 10-14mmHg
HTN:
>25 at rest
>35 during exercise
Calf pseudohypertrophy?
Muscular dystrophy (most commonly Duchenne): X-linked recessive deletion of dystrophin gene
pseudohypertrophy due to fibrofatty replacement of muscle
Lens subluxation?
Marfan syndrome
Homocystinuria
Gower’s sign?
Muscular dystrophy (Duchenne’s)
Cafe-au-lait spots? Mutation?
Neurofibromatosis type 1 (von Recklinghausen disease)
Autosomal dominant, 100% penetrant, variable expression.
Mutation in NF1 gene on chromosome 17
Tuft of hair on lower back?
Spina bifida occulta
failure of bony spinal canal to close, but no structural herniation
dura intact
Pt with severe low back pain that radiates down back of leg?
Sciatica?
Clinical definition of chronic bronchitis?
> 3 months per year for >2 years
What type of cell differentation and maturation takes place in the thymus? Which cells do you find MHC I on? Which cells have MHC II?
T cell maturation in thymus
MHC I: all nucleated cells (not on RBCs)
MHC II: antigen-presenting cells (APCs)
What is a type I (alpha) error?
stating that there is an effect or difference when none exists
(null hypothesis incorrectly rejected in favor of alternative hypothesis)
also known as “false-positive error”
alpha = probability of making a type I error
Type II (beta) error?
stating there is not an effect or difference when one exists
(null hypothesis is not rejected when it is in fact false)
a.k.a. false negative error
beta = the probability of making a type II error
Characteristic finding on electrophoresis for multiple myeloma? Classic finding in urine?
M spike on serum protein electrophoresis
Ig light chains in urine (Bence Jones protein)
Difference between emphysema caused by smoking vs. emphysema caused by alpha1-antitrypsin deficiency?
smoking = centriacinar
alpha1-antitrypsin deficiency = panacinar
What trace element is essential to the function of carbonic anhydrase and lactic dehydrogenase?
Zinc
Radical mastectomy: exercise extreme cause as you dissect laterally along serratus anterior muscle - what motor nerve are you avoiding? What sequela would result if you hit it?
Long thoracic nerve
winged scapula
cannot abduct arm above horizontal
Nutmeg liver?
right heart failure
Budd-Chiari syndrome
