NBME Form 12

Question 1

What would a kidney look like once it has healed from renal tubular necrosis w/o damage to underlying stromal framework/glomeruli?

Answer 1

Normal renal architecture

Question 2

Cause of scleral and facial icterus in a newborn

Answer 2

UDP glucoronosyltransferase deficiency

Question 3

What is the role of leptin in satiety?

Answer 3

Leptin is released from adipocytes when they are “full” thus decreasing hunger cravings and increasing satiety

Question 4

Gain of Function Mutation

Answer 4

A type of mutation in which the altered gene product possesses a new molecular function or a new pattern of gene expression. Gain-of-function mutations are almost always Dominant or Semidominant.

Question 5

What is the mechanism of action of norepinephrine?

Answer 5

a1>B1 mediated vasoconstriction –> increased mean arterial pressure and bradycardia.

Can be used to increase BP and peripheral vascular resistance

Question 6

What is the mecahnism of action of isoproterenol?

Answer 6

B>a. B2 mediated vasodilation –> decreased mean arterial pressure and B1 mediated increase in heart rate

Question 7

Cause of hypospadia?

Answer 7

failure of urethral fold to close

Question 8

Cause of epispadia?

Answer 8

faulty positioning of genital tubercle

Question 9

Mechanisms of action and side effects of Statins

Answer 9

MOA: blocks conversion of HMG-CoA to mevalonate (a cholesterol precursor)

Sdx: Hepatotoxicity and rhabdomyolysis

Question 10

What is oligohydramnios and what are the consequences?

Answer 10

<0.5L of amniotic fluid.

Renal agenesis, placental insufficiency, posterior urethral valves (in males) and inability to excrete urine.

Question 11

What is Potter’s Syndrome?

Answer 11

oligohydramnios –> compression of fetus leading to limb deformities and pulmonary hypoplasia (death)

Question 12

What is polyhydramnios, and what are the consequences?

Answer 12

> 1.5-2L of amniotic fluid.

Esophageal/duodenal atresia –> inability to swallow amniotic fluid and anencephaly

Question 13

When do coronary arteries have the most blood flow?

Answer 13

Early Diastole

Question 14

Mechanism of action and side effects of Haloperidol

Answer 14

MOA: high potency antipsychotic used for schizophrenia by reversibly blocking D2 receptors.

Sdx: extrapyramidal symptoms (parkinsonian stuff.)

Question 15

What is the mechanism of action of mebendazole?

Answer 15

Blocks microtubules to kill helminths

Question 16

Pathogenesis and presentation of Multiple Sclerosis?

Answer 16

A type IV hypersensitivity. Autoimmune inflammation and demyelination of CNS resulting in oligodendrocyte loss and reactive gliosis with destruction of neurons.

Clx: Optic neuritis, MLF syndrome, scanning speech, intention tremor

Question 17

Reaction to jewelry (contact dermititus) is what type of hypersensitivity?

Answer 17

Type IV: delayed

Question 18

Variable Expressivity (and what disease is this common in)

Answer 18

def: phenotype varies among individuals with same genotype
ex: NF1 pts from same family may have varying disease severity

Question 19

What are the clinical signs of multiple myeloma?

Answer 19

CRAB: calcemia, renal insufficiency, anemia, bone lytic lesions.

susceptibility to infections, anemia symptoms, lytic bone lesions, M-spike on protein electrophoresis, roleaux formation of RBCs (stacks), clock face plasma cells