USMLE Rx: Week of 11/29/16

Question 1

What syndrome presents with thrombocytopenia, eczema, and recurrent pyogenic infections?

Answer 1

Wiskott-Aldrich syndrome (think WATER: Wiskott-Aldrich = Thrombocytopenia, Eczema, and Recurrent pyogenic infections)

This is an X-linked disorder in which boys can’t mount an IgM response to bacteria. IgA and IgE will be elevated.

Question 2

The internal jugular vein is ___________ to the common carotid artery.

Answer 2

lateral

Question 3

The disorder that presents with hypogonadism, short stature, obesity, and intellectual disability results from methylation of chromosome ____.

Answer 3

15

Question 4

True or false: a living will does not override durable power of attorney.

Answer 4

True. Durable power of

Question 5

Those with ____________ deficiency are at increased risk of GI infections.

Answer 5

selective IgA

Question 6

A patient who has an absent patellar reflex might also have numbness where?

Answer 6

The back of the thigh, back of the calf, and lateral side of the foot

Question 7

Disc herniation will present with pain when _____________.

Answer 7

the leg is bent

Question 8

In addition to affected mastication muscles, impairment in V3 will also present with _____________.

Answer 8

jaw deviation, because V3 also innervates the pterygoid muscles

Question 9

The palms and soles of the feet have what additional layer of skin?

Answer 9

Stratum lucidum

Question 10

Urine sodium greater than 20 mEq/L indicates what type of renal injury?

Answer 10

Intrinsic (renal)

Question 11

Urine osmolality will be _____________ in both prerenal and postrenal azotemia.

Answer 11

less than 350 mOsm/kg

Question 12

What is the confirmatory test for HIV?

Answer 12

Immunoassay

Question 13

Cervical LAD with buccal and pharyngeal thrush should raise suspicion for _____________.

Answer 13

AIDS

Question 14

Drugs that inhibit ______________ can help prevent male-pattern baldness.

Answer 14

5-alpha reductase (which converts testosterone to dihydrotestosterone)

Question 15

There are two sets of veins that can produce hemorrhoids. Differentiate them.

Answer 15

Hemorrhoids from the superior rectal veins are internal (i.e., cannot be seen from outside) and are not innervated by pain-sensing neurons. Hemorrhoids from the inferior rectal vein can be seen from outside and are painful.

Question 16

What genetic syndrome is strongly associated with Hirschprung’s?

Answer 16

Down syndrome

Question 17

The leading cause of small bowel obstruction is ____________.

Answer 17

abdominal surgery

Question 18

Bilateral lesions of the amygdala (from a stroke, for instance), result in what syndrome?

Answer 18

Klüver-Bucy syndrome: hypersexuality, hyperorality, anterograde amnesia, and disinhibition

(Without your amygdala, you’re not afraid to put your mouth on stuff. Also, think Busy Luver.)

Question 19

What disorder might you think of if a father and son both had violent shaking movements of the legs?

Answer 19

Hereditary spastic paraplegia (caused by disturbances in the corticospinal tract that result in spasm rather than paralysis)

Question 20

Most trisomies are caused by a problem in which step of mitosis/meiosis?

Answer 20

Anaphase I of meiosis (because this is when the chromosomes must separate)

Question 21

True or false: the femoral sheath contains the femoral nerve, artery, and vein.

Answer 21

False. The sheath only contains the blood vessels.

Question 22

What virus presents with the POM-Pom symptoms?

Answer 22

Mumps! 
Parotitis
Orchitis (can lead to infertility) 
Meningitis
Pancreatitis

Question 23

The ductal cells of the salivary gland secrete ____________ into the saliva. As flow rate increases, this substance will decrease in concentration.

Answer 23

potassium

Question 24

There are three main therapeutics for ulcerative colitis. Describe the order in which you’d prescribe them.

Answer 24

First sulfasalazine, which gets metabolized to 5-aminosalicylic acid that decreases inflammation locally.

If that fails to work, switch to steroids.

If steroids fail to work, give infliximab.

Question 25

The drug that is in Neosporin is not used systemically because it can cause nephrotoxicity. What is its name and mechanism?

Answer 25

Bacitracin; works by inhibiting the transport of mucopeptides to the outside of the cell, thereby disrupting peptidoglycan synthesis

Question 26

What antiviral is contraindicated in severely depressed or suicidal patients?

Answer 26

Interferon, because it leads to a flu-like response characterized by fever, chills, and depression

Question 27

Recall that drugs like sodium nitroprusside decrease ____________.

Answer 27

afterload

Question 28

True or false: Dubin-Johnson syndrome presents with jaundice in infancy.

Answer 28

False. It is often asymptomatic in infants. Obstructive jaundice in infants suggests biliary atresia.

Question 29

Without surgical intervention, biliary atresia leads to what outcome?

Answer 29

Cirrhosis in infancy

Question 30

What genetic causes lead to Gilbert and Crigler-Najar?

Answer 30

Gilbert = defect in promoter region
Crigler-Najar = defect in enzyme

Question 31

What is one key feature that distinguishes antimuscarinic toxicity from cocaine toxicity?

Answer 31

Sweating is decreased in anticholinergic overdose and increased in cocaine overdose.

Question 32

What is the mechanism of the recreational drug that causes nystagmus?

Answer 32

Blocks NMDA receptors

Question 33

Infusion rate should equal ______________.

Answer 33

steady state concentration x clearance

Question 34

Steady state concentration equals ________________.

Answer 34

infusion rate / clearance rate

Question 35

A “down and out” eye with a non-responsive pupil indicates _________________.

Answer 35

oculomotor nerve damage

Question 36

True or false: resistance to cephalosporins is most often by beta-lactams.

Answer 36

False. It’s by altering penicillin-binding proteins.

Question 37

Type I hypersensitivity reactions are initiated by what cell type?

Answer 37

Mast cells!

Question 38

Which antibiotic binds to the 23S subunit of the 50S subunit?

Answer 38

Macrolides

Think: “My ChROmosomes have 23 pairs.”

Question 39

Resistance to macrolides occurs by the _________________.

Answer 39

methylation of the 23S subunit

Question 40

“Walking pneumonia” implies ______________.

Answer 40

Mycoplasma infection (treat with macrolides)

Question 41

Pneumonia with Gram-negative rods in a teen with CF is generally ________________. Treat with _____________.

Answer 41

Pseudomonas aeruginosa; piperacillin/tazobactam and an aminoglycoside

Question 42

The antibiotic that causes tendonitis has what mechanism?

Answer 42

inhibits DNA gyrase (this being the fluoroquinolones)

Question 43

Guillain-Barré syndrome results from ________________.

Answer 43

inflammatory demyelination

Question 44

Make a card for metachromatic leukodystrophy.

Answer 44

Ok!

Question 45

Make a card for Hartnup.

Answer 45

Ok!