3 Flashcards
How does flutamide differ from finasteride in relation to mechanism of action and clinical use?
(FA15 p597) (FA16 p603)
BOTH used for prostate pathology:
- flutamide: A nonsteroidal competitive inhibitor at androgen receptors. Used for prostate CARCINOMA.
- finasteride: A 5α-reductase inhibitor (conversion of testosterone to DHT). Useful in BPH and male-pattern baldness.
Which bone is commonly fractured when falling on an outstretched hand, resulting in deep pain in the anatomical snuffbox?
scaphoid
What might you observe in a patient who presents to the emergency room with PCP intoxication?
(FA15 p519) (FA16 p523)
horizontal and vertical nystagmus, also belligerence, impulsivity, fever, psychomotor agitation, analgesia, tachycardia, homicidality, psychosis, delirium, seizures (i.e.: resistant, aggressive, violent)
Treatment: benzos, rapid-acting antipsychs.
w/drawal: Depression, anxiety, irritability, restlessness, anergia, disturbances of thought and sleep
IFN-γ stimulates macrophages and inhibits Th2 cells. What cell type releases IFN-γ? (FA15 p202) (FA16 p194)
Th1 helper cells
How does the mechanism of action of benzodiazepines differ from the mechanism of action of barbiturates? What toxicities of barbiturates can be fatal? (FA15 p497) (FA16 p501)
- benzos: Facilitate GABAa action by increasing frequency of Cl− channel opening (“Frenzodiazepines” increase frequency)
- barbs: Facilitate GABAa action by increasing DURATION of Cl− channel opening, thus decreasing neuron firing (barbiDURAtes increase DURAtion, also barbs are hard (“dura”) drugs)
- barbs may cause CNS, resp. and CV depression (hypovent. and bradycardia), WORSE in presence of etOH
What are the symptoms of decompression sickness?
the “bends”: nitrogen gas embolus–>paralysis, risk of stroke
- joint and musc. pain (85-90%)
- neuro symptoms: dizziness, syncope, paralysis (5-10%)
- “the chokes”: dyspnea, pulm. edema, death (2%)
A 40-year-old man is beginning to have symptoms of a resting tremor, postural instability, and mask- like (expressionless) facies. What is the antiviral drug that can be used against this disease, and what is its mechanism of action? (FA15 p500-501) (FA16 p504-505)
parkinsonism; Amantadine:
increases dopamine release and
decreases dopamine reuptake); also used as an antiviral against influenza A (not used as much anymore) and rubella; toxicity = ataxia, livedo reticularis.
A 28-year-old man is being treated with the combination of bleomycin, etoposide, and cisplatin for metastatic non-seminoma testicular cancer. The patient develops shortness of breath during the course of treatment. Pulmonary function testing indicates that he has a restrictive lung disease. Which of the chemotherapy agents is responsible for this restrictive lung disease? Which agent in the above regimen works by inducing free radicals to interfere with DNA structure? (FA15 p410) (FA16 p410)
Bleomycin: causes Pulmonary fibrosis
ALSO Induces free radical formation–> breaks in DNA strands.
also: busophan and methotrexate
A 55-year-old alcoholic is admitted to the hospital for an upper GI bleed. A ruptured esophageal varix is found to be the cause. What is the preferred medical treatment for this condition? (FA15 p378-379) (FA16 p374-375)
Octreotide: Long-acting somatostatin analog; inhibits actions of many splanchnic vasoconstriction hormones.
uses: Acute variceal bleeds, acromegaly, VIPoma, carcinoid tumors.
A 3-day-old preterm infant delivered at 34 weeks gestation develops neonatal respiratory distress syndrome (RDS). Which type of pneumocyte is affected in RDS? What is the mechanism that leads to poor O2-CO2 exchange at the gas exchange barrier in preterm infants with RDS? What structures make up the gas exchange barrier? How could you increase surfactant production in preterm neonates? (FA15 p600, 613) (FA16 p607)
type II pneumocyte: surfactant deficiency, alveolus can’t expand due
to increased surface tension
“hyaline membrane disease of the newborn”
-barrier: Type I pneumocytes, BM of pulm. caps, endothelial cells of pulm. caps
-Treatment: maternal steroids before birth (will mature the pneumocytes); artificial surfactant for infant.
(surfactant synthesis begins around week 26 of gestation, but mature levels are not achieved until around week 35)
FA neonatal respiratory distress syndrome
Surfactant deficiency–> inc. surface tension–>alveolar collapse (“ground-glass” appearance of lung fields)
-lecithin:sphingomyelin ratio
What is the antidote for digoxin toxicity? (FA15 p220) (FA16 p214)
Vitamin K+, Mg+, lidocaine, pacemaker
or digoxin immune Fab fragments (DigiFab)
What are some of the circumstances in which information is HIPAA-exempt, meaning that your health information can be shared with another party?
- child abuse
- birth/death
- state mandated reportable illness
- public health disease intervention
- state sponsored disease intervention activities
- schools (vaccination status)
my guess: when the patient has violent/self-destructive/suicidal/homicidal intentions/actions
hydatidiform mole is the most common precursor of what ovarian germ tumor? What tumor marker is monitored after the dilation and curettage of a hydatidiform mole? (FA15 p580) (FA16 p587)
choriocarcinoma
Monitor β-hCG
(worried if stays elevated)
what is it?? Cystic swelling of chorionic villi and proliferation of chorionic epithelium (only trophoblast). Associated with theca-lutein cysts, hyperemesis gravidarum, hyperthyroidism. also tx w. methotrexate along w. dilation and curettage
You are reading a research article about the prostate specific antigen test, and it mentions that the PSA blood test is associated with a high false positive frequency. In your own words, explain what false positive means. (FA15 p49) (FA16 p33)
a healthy person testing as if they have the disease/condition (when it is not there)
A young woman complaining of easy bleeding and menorrhagia was referred by her OB/GYN for work- up of her bleeding disorder. Your preceptor tasks you with determining the cause of the patient’s condition. Compare the clinical findings of platelet disorders to those of coagulation factor defects. (FA15 p397) (FA16 p396-397
platelet disorder:
1st part of hemostasis: Defects in platelet plug formation–>inc. bleeding time (BT) (NORMAL PT/PTT)
Platelet abnormalities–>microhemorrhage: mucous membrane bleeding, epistaxis, petechiae, purpura, inc. bleeding time, possibly decreased platelet count (PC)
coagulation disorder:
2nd part: generation of clot: prolonged PT/PTT (NORMAL bleeding time)
PT—tests function of common and extrinsic pathway (factors I, II, V, VII, and X). Defect–> inc. PT.
PTT—tests function of common and intrinsic pathway (all factors except VII and XIII). Defect–>inc. PTT
major hemorrhage: hemarthorsis, IC hemorrhage
A 45-year-old woman presents to the ER with complaints of chest pain, a racing heart beat, and dizziness. Examination reveals a heart rate of 120 /minute, blood pressure of 116/74 mm Hg, and 20 respirations/minute. The patient is diaphoretic and anxious. An initial EKG reveals ventricular tachycardia with shifting sinusoidal waveforms. What is this classic EKG finding? What are the possible causes of this patient’s condition? (FA15 p283) (FA16 p277)
Torsades de pointes -Drug-induced long QT (ABCDE): AntiArrhythmics (class IA, III) AntiBiotics (e.g., macrolides) Anti“C”ychotics (e.g., haloperidol) AntiDepressants (e.g., TCAs) AntiEmetics (e.g., ondansetron)
- also hypokalemia, hypomagnesemia
- congenital long QT syndromes
How does MRI differ from CT imaging?
MRI: no ionizing radiation, best for soft tissue (brain, SC, ligaments, cartilage (i.e. ACL tear), caution w. metal (i.e. pacemakers), bones show up GRAY
CT: uses ionizing radiation (not as good for preggos), best for bone detail and blood recognition, no prob w. metal, bones show up WHITE
A patient of yours with recent complaints of weakness, pallor, craving for ice chips and tachycardia has a history of chronic hemorrhoids. What do you immediately suspect is the cause of this patient’s anemia and how do you treat it? (FA15 p390) (FA16 p388)
Iron deficiency anemia, tx with iron replacement, possible colonoscopy to eval. for colon cancer
What enzymes do obligate anaerobes lack? (FA15 p121) (FA16 p111)
catalase and/or superoxide dismutase
What embryological structural abnormalities might account for multiple miscarriages? What structures arise from the paramesonephric ducts? What other name is given to the paramesonephric ducts? (FA15p567-568)(FA16p571-572)
Incomplete fusion of paramesonephric ducts
-uterus, fallopian tubes, upper portion of vagina (lower from UG sinus)
also called Mullerian ducts
An elderly patient fell and struck his head on a coffee table. His family brought him to the ER. He is currently conscious and at his neurological baseline. Non-contrast CT of the head reveals a crescent shaped radiopacity that follows the contour of the skull crossing suture lines. What type of intracranial hemorrhage might this be and which vessel(s) would be involved? (FA15 p466) (FA16 p469)
subdural hemorrhage
-rupture of bridging veins (slow venous bleeding, crosses suture lines, midline shift, CANNOT cross falx, tentorium)
IN CONTRAST:
epidural hematoma: rupture of MMA (often 2o to temporal bone fx) (lucid interval, rapid expansion) BICONVEX (lentiform, “contact lens shape” blood collection)
NOT crossing suture lines, can cross falx, tentorium
Where is most of the cerebrospinal fluid (CSF) generated? What is the function of CSF?
choroid plexuses of lateral ventricles (2)
- supports/cushions/suspends the brain
- homeostatic medium for regulation of pH, e-lytes
- route for chem messengers to be distributed in the nervous system
A child presents with nephritis, deafness and ocular dysfunction. What is the diagnosis? A gene defect in what type of collagen contributes to the dysfunctions associated with this syndrome? What type of collagen organizes bone, skin and tendons? What type of collagen organizes cartilage?
(FA15 p75, 541) (FA16 p61, 547)
Alport syndrome, mutation in Type 4 collagen: hinning and splitting of glomerular basement membrane. Most commonly X-linked, Eye problems (e.g., retinopathy, lens dislocation), glomerulonephritis, sensorineural deafness; “can’t see, can’t pee, can’t hear a buzzing bee” (or “can’t hear high C”). “Basket-weave” appearance on EM.
Type 1: bONE, Most common (90%)—Bone (made by osteoblasts), Skin, Tendon, dentin, fascia, cornea, late wound repair.
Type 2: carTWOlage, (including hyaline), vitreous body, nucleus pulposus.
Type 3: reticular collagen (skin, blood vessels, uterus, fetal tissue, granulation tissue)
Type 4: FLOOR, basement membrane, basal lamina, lens
A child is noticed to be yellow by a visiting relative, so he was brought to the clinic. His exam revealed jaundice and splenomegaly. The patient’s lab results reveal anemia and spherocytes. What test is used to confirm the diagnosis of hereditary spherocytosis? What findings are associated with hereditary spherocytosis? (FA15 p394) (FA16 p392)
osmotic fragility test ⊕ (flow cytometry more common now)
Splenomegaly, aplastic crisis (parvovirus B19 infection)
small, round RBCs with less surface area and no central pallor; inc. MCHC, inc. RCW, extravascular hemolysis, neg Coombs test
Spheroid erythrocytes (instead of disc) due to defect in RBC cytoskeleton proteins: spectrin, ankyrin, band 3, pallidin; hemolytic anemia; Treatment: splenectomy.
What is the composition of a nucleosome? Which histone ties nucleosomes together? (FA15 p62) (FA16 p48)
Negatively charged DNA loops twice around positively charged histone octamer to form nucleosome “beads on a string.” H2A, H2B, H3, H4 (2 of each)
Histones are rich in the amino acids lysine and arginine. H1 binds to the nucleosome and to “linker DNA,” thereby stabilizing the chromatin fiber.
At what positive G force does visual “black-out” occur? Why does this occur?
4-6 Gs: pooling blood in abdomen, legs
The dorsal root ganglion is considered gray matter within the spinal cord. From what embryological derivative are the dorsal root ganglia derived? (FA15 p559) (FA16 p563)
Neural crest (derived from ectoderm)—think PNS and non-neural structures nearby
IN CONTRAST:
Neuroectoderm—think CNS.
A 40-year-old woman treated with lisinopril for stage I hypertension becomes pregnant. Why are ACE inhibitors contraindicated in pregnancy? What centrally acting α2-agonist is often used to treat hypertension in pregnancy? (FA15 p254) (FA16 p247)
- teratogenic: cardiac CNS malformations in 1st trim, renal probs in 2nd, 3rd (along w. ARBs)
- use methyldopa used instead
Which complement protein is an opsonin? Which complement protein aids in neutrophil chemotaxis? Which complement proteins form the membrane attack complex? (FA15 p206) (FA16 p199)
*C3b: opsonization (IgG is also an opsonin)
*C5a: neutrophil chemotaxis
C3a, C4a, C5a: anaphylaxis
C5b-C9: cytolysis by MAC
A 42-year-old obese man presents with a complaint of severe pain in his right knee. He believes he injured it while dancing at his cousin’s wedding last night. You suspect gout. How would you differentiate between gout and pseudogout upon exam of synovial fluid aspirate? (FA15 p430-431) (FA16 p431) (SU p233)
Gout—monosodium urate crystals, needle-shaped; are yellow when parallel (||) to the light.
Pseudogout—calcium pyrophosphate crystals, rhomboid-shaped; blue when parallel (||) to the light.
What enzyme catalyzes the rate-limiting step in cholesterol synthesis? What class of drugs inhibits this enzyme? (FA15p96)(FA16p84)
HMG-CoA reductase the Statins (HMG-CoA reductase inhibitors)
What arteries supply the adrenal glands? From what arteries do these arteries arise?
superior adrenal art. from inferior phrenic art.
middle from aorta
inferior from renal artery
Many factors are involved in the proper morphogenesis of organs in utero. In the case of oligohydramnios, lack of fluid flowing in and out of the fetal lungs leads to pulmonary hypoplasia. This is an example of which type of error in organ morphogenesis? (FA15 p559) (FA16 p563)
hypoplasia: Incomplete organ development; primordial tissue present.
Given the following scenarios describe the corresponding complement deficiency? (FA15 p206) (FA16 p199)
Frequent Neisseria infections
Frequent pyogenic RTIs
Paroxysmal nocturnal hemoglobinuria
Increased frequency of type III hypersensitivity reaction
- Frequent Neisseria infections: C5-9 def.
- Frequent pyogenic RTIs: C3 def. (can’t phago. encapsulated bac: H. flu, S. pneumo)
- Paroxysmal nocturnal hemoglobinuria: DAF (GPI-anchored enzyme deficiency (CD55, CD59): (also Causes complement-mediated lysis of RBCs)
- Increased frequency of type III hypersensitivity reaction: again C3 def
bonus: C1 esterase inhibitor deficiency causes hereditary angioedema. ACE inhibitors are contraindicated
Which neoplasm is most commonly responsible for the following paraneoplastic effects? (FA15 p238) (FA16 p229) ACTH-->Cushing’s syndrome PTH-related peptide-->hypercalcemia Erythropoietin-->polycythemia ADH-->SIADH
- ACTH–>Cushing’s syndrome: *SmallCC, RenalCC
- PTH-related peptide–>hypercalcemia: *SqCC, RenCC, breast cancer
- Erythropoietin–>polycythemia: RenCC, hemangioblastoma, HepCC, leiomyoma, pheochromocytoma
- ADH–>SIADH: SmCC, intracranial neoplasms
What nerve is damaged when a patient presents with the following symptom (upper extremity): Claw hand
(FA15 p418-420) (FA16 p419-421)
Ulnar
What nerve is damaged with ape hand
median
What nerve is damaged with wrist drop
radial
What nerve is damaged with scapular winging
long thoracic
What nerve is damaged with inability to wipe bottom
thoracodorsal
What nerve is damaged with loss of forearm pronation
median
What nerve is damaged with inability abduct or adduct fingers
ulnar
What nerve is damaged with loss of arm abduction
axillary
What nerve is damaged with weak lateral rotation of arm
suprascapular and/or axillary
What nerve is damaged with loss of arm and forearm flexion
musculocutaneous
What nerve is damaged with loss of forearm extension
radial
What nerve is damaged with trouble initiating arm abduction
suprascapular
What nerve is damaged with inability to abduct arm beyond 10 degrees (FA says 15)
axillary
What nerve is damaged with inability to raise arm above horizontal
long thoracic
What renal pathology is characteristic of RBC casts and proteinuria? (FA15 p539-541) (FA16 p544-547) (SU p104, 154)
Glomerulonephritis (GNP) and malignant hypertension (w. end organ damage to kidneys)
(Presence of casts indicates hematuria/pyuria is of glomerular or renal tubular origin)
bonus: WBC casts: Tubulointerstitial inflammation, acute pyelonephritis, transplant rejection
In which pulmonary disease would you see an increased Reid index? (FA15 p610) (FA16 p618)
chronic bronchitis and COPD (>50%) implies hyperplasia of mucus-secreting glandes in bronchi
A 56-year-old man develops right lower extremity edema after returning from Europe from a business trip. An exam of the right lower extremity demonstrates a red, warm, lower leg with a positive Homan’s sign. What is the patient’s diagnosis? What is a positive Homan’s sign? What is Virchow’s triad? What is the most common inherited hypercoagulability syndrome? (FA15 p608) (FA16 p616)
DVT
+ Homan’s: pain in calf upon foot dorsiflexion
Virchow’s: stasis, hypercoagability, endothelial damage
most common inherited: Factor V Leiden mutation (can’t degrade Factor V via Protein C)
Which adrenergic antagonists can be used to treat hypertension as well as urinary retention in patients with benign prostatic hyperplasia (BPH)? What is the difference between the prostate exam findings in BPH versus adenocarcinoma of the prostate? (FA15 p594) (FA16 p599)
α1-antagonists: *terazosin, *tamsulosin, prazosin, doxazosin
MOA: cause relaxation of smooth muscle
BPH: lateral and middle lobe (periurethral) hyperplasia; prostate is symmetric, smooth and enlarged
adenocarcinoma of the prostate: posterior lobe (peripheral zone); prostate is asymmetric w. a hard nodule
bonus: also can tx BPH with 5α-reductase inhibitors (e.g., finasteride) and PDE-5 inhibitors.
