Usmle Step 3 Qbank Review

Front 1

Carotid endarterectomy should be done in pts with carotid stenosis that is ____

Back 1

>70%

Front 2

Intussusception can be diagnosed by ____

Back 2

US (high sens & spec, look for pseudokidney or target), and then progress to air/water enemas.

Front 3

In the diagnosis/tx of intussusception, bowel perforation 2/2 enema (<1%) is highest in 2 groups:

Back 3

infants < 6mths who have had symptoms > 3 days
pts with SBO symptoms

Front 4

When an international pt presents with hematuria & anemia, think ___

Back 4

schistosomiasis!

Front 5

How to diagnose schistosomiasis?

Back 5

Urine microscopy (preferably collected between 10am-2pm) to show parasite egg excretion. If urine samples neg and clinical suspicion high, then do cystoscopy w biopsy.

Front 6

Arthritis in the 2nd and 3rd MCP, think _____

Back 6

hemachromatosis!

Front 7

Polyarthritis (shoulders, knees, ankles), DM, weakness, decreased libido, hepatomegaly...in a 50-60 yo, think ____

Back 7

hemachromatosis! % sat > 50% and elevated ferritin & serum iron.

Hint 7

Note that many will test falsely pos for Lyme, so don’t draw titers unless there is high clinical suspicion for Lyme.

Front 8

Note that 50% of pts with hemachromatosis and arthritis have ____ on arthrocentesis

Back 8

Pseudogout (so on aspiration, you will find CPPD crystals w positive birefringence)

Front 9

__ and __ spares the MCP joints

Back 9

OA & Reiter’s

Front 10

___ involves MCP joints, but also has

morning stiffness that lasts > 1 hr
no crystals in synovial fluid
erosions on Xray (rather than the subcondral cysts/sclerosis seen with hemochromatosis)

Back 10

RA!

Front 11

Why monitor BP closely in pts with scleroderma? What is the tx for this elevation in BP?

Back 11

Because, though rare, sclerodermal renal crisis can occur. Caused by deposition of collagen in the renal arteries leading to stenosis and then ischemia, setting off the renin-angiotensin system, leading to malignant hypertension.

Hint 11

Thus, the treatment would be ACEi (captopril is the agent of choice), and one dose of IV nitroprusside if papilledema and CNS sx’s are present, to lower the BP as the ACEi takes effect.
Unlike other pts in ARF, scleroderma pts in ARF need an ACEi!

Front 12

Sudden onset ARF after diarrhea, think ___

Back 12

Hemolytic Uremic Syndrome!

Front 13

For correlation coefficient r = -0.39 and p = 0.005. A (weak/strong), (positive/negative) correlation is observed.

Back 13

weak, negative! though it is statistically significant based on the p-value.

Front 14

Criteria for determination of brain death:
1. Apnea for about __ to __ minutes off ventilator, enough to produce hypercarbic drive (pCO2 of 50-60 mmHg)
2. Body temperature below ___
3. EEG isoelectric for ___ minutes
4. Absence of _____ by Dopper or MRA
5. At least ___ hrs observation in adults with anoxic-ischemic brain damage

Back 14

1. 10 to 20
2. 34 C (93.2 F)
3. 30
4. cerebral circulation
5. 24

Front 15

If a young person presents with fever, fatigue and a systolic murmur with tricuspid valve abnormality, think____. If the same scenario but with mitral valve abnormality, think ___ or ___.

Back 15

Endocarditis from IVDA (right-sided heart involvement)
Rheumatic fever or Lupus (left-sided heart involvement)

Front 16

A healthy man with normal AST/ALT, no h/o IVDA, or sexual promiscuity has positive Anti-HCV ab. What should you do?

Back 16

Get a HCV RNA. Diagnosis is unclear, because PPV of ELISA in a low-risk person with normal AST/ALT is only 35-45%.

Front 17

Low-grade fever, posterior cervical and occipital lymphadenopathy, maculopapular rash beginning on the face and spreads down, think_____

Back 17

Rubella (aka German Measles)...supportive care only

Front 18

Cough, Conjunctivitis, Coryza...maybe also some Koplik spots, maculopapular rash beginning on the face and spreads down, think ____

Back 18

Rubeola (aka measles)

Front 19

High fever that resolves, followed by rosy nonpruritic rash on the trunk and spreading to the extremities, think ____.

Back 19

Roseola!

Front 20

What is the most common SE of Isoniazid? What is another SE for which you should add another agent?

Back 20

hepatotoxicity! ocular toxicity is less common
peripheral neuropathy because INH is a Vit B6 (pyridoxine) antagonist, so should add pyridoxine

Front 21

What is the most common SE of ethambutol?

Back 21

ocular toxicity!

Front 22

What is the most common SE of Rifampin?

Back 22

reddish-orange discoloration of urine, feces, sweat, tears, sputum

Front 23

What is the most common SE of Procainamide and Hydralazine?

Back 23

Drug-induced lupus

Front 24

A patient with subclinical hypothyroidism, who also has depression and irregular heavy menstrual cycles, you should ___.

Back 24

Start levothyroxine rather than wait because pt is symptomatic!

Front 25

Standard caloric intake is ___ kcal/kg/day. Standard protein intake is ___ g/kg/day.

Back 25

30, 1

Front 26

Acute gout should be treated with ____

Back 26

Indomethacin or ibuprofen. Colchicine or glucocorticoids can also be used. (FYI Colchicine is given 0.6mg/hr until relief of sx’s, max of 2mg, or GI toxicity occurs).

Front 27

Why not start allopurinol or probenacid during acute gout?

Back 27

These hypouricemic therapies can cause flare-up of the acute gout.

Front 28

Muscular dystrophy usually symptomatic around ___ yo, but CK levels are elevated by ___ yo and then normalize as the muscle is replaced by fat/fibrosis.

Back 28

10-12, 2

Front 29

Match calcium phosphate crystals and calcium oxalate crystals to the following scenarios:
1. Bipyramidal crystals with variable birefringence
2. Large coin-like crystals on light microscopy

Back 29

1. Calcium oxalate crystals. Seen in pts with ESRD. Kidney transplantation cures this type of arthritis.
2. Calcium phosphate crystals. Causes a large cool effusion, usually of the shoulder joint, known as Milwaukee shoulder.

Front 30

Match small cell carcinoma and squamous cell carcinoma with the following:
1. a/w hypercalcemia 2/2 PTHrP, cavitary lesion in a bronchus
2. a/w SIADH

Back 30

1. squamous cell
2. small cell

Front 31

You use either demeclocycline or lithium in this scenario. You can also add on furosemide with hypertonic saline.

Back 31

Hyponatremia that does not respond to water restriction. Demeclocycline is preferred over lithium because it’s more effective and less toxic. Furosemide looses Na, but used to get rid of water when mixed with hypertonic saline.