UWorld Tests 6/2/2014

Question 1

What is a rare neurologic complication of measles?

Answer 1

Subacute sclerosing encephalitis. Thought to be a strain of measles that does not that the antigen M protein, therefore antibodies doesn’t effectively clear it. Antibodies to the M protein in titers are missing. There are high titers of antibodies to measles and oligoclonal bands of immunoglobulins

Question 2

What is the most common tumor of the urinary tract system? PPT?

Answer 2

Transitional cell carcinoma. Peak incidence in 7th/8th decade of life with increased incidence in men over women. PAINLESS hematuria with no casts.

Question 3

RFs for transition cell carcinoma

Answer 3

These can affect your P SAC- Phenacetin use, smoking, aniline dyes, cyclophosphamide. Increased risk with exposure to RUBBER??

Question 4

What can lead to bilateral wedge shaped bands of necrosis over the cerebral convexity?

Answer 4

Cerebral hypoperfusion - for example, after an MI - leads to infarcts in the watershed areas.

Question 5

Kidney embryology - short sequence

Answer 5

Urogenital ridge formed by the mesoderm => neprhogenic cord. Proneprhos - completely regresses by weak 4; mesonephros - interim kidney in 1st semester - gives rise to wolffian duct; true kidnecy coems from metanephros. Ureteric bud sprouts off caudal mesonephric duct => penetrates intermediate mesoderm and incudes it to form metanephric mesoderm. Ureteric bud => collecting system i.e., ureters, calyxes, pelvis, collecting duct, Metanephric blaster => glomeruli through DCT.

Question 6

Friedrich’s ataxia affects NS how?

Answer 6

Causes spinocerebellar tract degeneration causing ataxia, also degeneration of dorsal columns and dorsal root ganglia causing loss of position and vibration sense.

Question 7

Most dangerous side effect for Amphotericin B. What can ensue?

Answer 7

Nephrotoxicity. Anemia and electroylte imbalances. Hypokalemia=> weakness and arrythmias, T wave flattening, ST segment depression, prominent U waves, premature atrial and ventricular contractions. Profound hypokalemia => v tach/ a fib

Question 8

Hyperaldosteronism can cause (primary conn) can cause what?

Answer 8

Causes hypkalemia and metabolic alklaosis, causing muscle weakness and paresthesias.

Question 9

How do you calculate attributable risk

Answer 9

AR = event rate in treatment group - event rate in placebo group. (ATP)

Question 10

Transmural inflammation of the arteries + fibrinoid necrosis..think what?

Answer 10

Polyarteritis nodosa

Question 11

How does polyarteritis nodosa present? What kind of infection is it a/w?

Answer 11

Fever, weight loss, malaise headache, GI symptoms like melena, abdominal pain

Question 12

PCL and ACL attachments?

Answer 12

PCL posterior tibia to anterior MEDIAL epicondyle of femur. ACL - anterior tibia to anterior LATERAL epicondyle of femur.

Question 13

Dark color in urine after refusing blood transfusion, think?

Answer 13

Acute hemolytic reaction. Dark color from the hemoglobin

Question 14

KNOW THE DIFFERENCE BETWEEN GP41 AND GP120

Answer 14

Gp120 is the big flower type looking thing compared to the skinny stalk. 120 = bigger number = big flower thing

Question 15

MOA of enfuvirtide and maraviroc?

Answer 15

Enfuvirtide => binds gp41 inhibiting viral fusion and entry. Maraviroc = binds CCR5 on T cells/monocytes, inhibiting interaction with gp120/attachment.

Question 16

What is maple syrup urine disease?

Answer 16

Defect in the breakdown of branched chain amino acids due to defect in alpha ketoacid dehydrogenase. Normally gets broken down to acetyl coA but can’t and tissue and serum levels of alpha-ketoacids begin to rise which leads to neurotoxicity

Question 17

What are the branched chain amino acids?

Answer 17

Leucine, isoleucine and valine

Question 18

What bacteria lacks peptidoglycan in its cell wall?

Answer 18

Chlamydia. Ureaplasma urealyticum lacks a cell wall entirely

Question 19

Causes of aortic stenosis

Answer 19

Calficiation, congenital bicuspid valve with calcification, rheumatic heart disease

Question 20

Aortic stenosis causes what kind of murmur

Answer 20

Harsh crescendo decrescendo systolic murmur heard between the 2nd intercostal space on right, with radiation to the carotids

Question 21

Treatment for DKA is?

Answer 21

Insulin and normal saline

Question 22

What does insulin and saline infusion do for DKA?

Answer 22

Insulin => allows glucose to be utilized more => less keton production => less acid production and consequent rise in bicarbonate levels. Insulin also causes K+ to go into cells => drives potassium into cells

Question 23

Carotid sinus baroreceptors and aortic arch baroreceptors send signals via which nerves

Answer 23

1) glossopharyngeal 2) vagus

Question 24

In patients with aortic stenosis and concentric LVH, what contributes significantly to ventricular filling?

Answer 24

Atrial contraction. Sudden decrease in pre-load due to afib or something => severe hyopotension

Question 25

Loss of myocyte contractility occurs how fast? When does ischemic injury become reversible?

Answer 25

Occurs within 60 seconds after the onset of total ischemia. When ischemia lasts less than 30 minutes, reperfusion => restoration of blood flow leads to reversible contractile dysfunction with contractility gradually returning to normal over next several hours/days

Question 26

Bounding femoral pulses accompanied by head bobbing is characteristic of?

Answer 26

Aortic regurgitation

Question 27

S3 sound can be accentuated by what position / action?

Answer 27

Lying in left lateral decubitus position and upon exhale. At end of exhale => lung volume smaller, heart is closer to chest wall.

Question 28

Aortic regurgitation does what to pulse pressure?

Answer 28

Widens pulse pressure

Question 29

BNP and ANP are elevated in what kind of cardiac disease?

Answer 29

Heart failure. Systolic dysfunction => increaesd volumes => increased ventricle and atria stretch => release of ANP and BNP

Question 30

What embryological structure gives rise to the superior vena cava

Answer 30

Common cardinal veins

Question 31

Cardiac tissue conduction velocity, fastest to slowest?

Answer 31

Park at ventricular avenue => purkinje, atrial muscle, ventricles, av node

Question 32

What are the identifying tests/characteristics for enterococcus?

Answer 32

Gram +, catalase -, gamma hemolytic, able to grown in 6.5% nacl and bile.

Question 33

2 most common cardiac diseases in Marfan’s?

Answer 33

Mitral valve proloase and cystic medial generation of the aorta

Question 34

Know the jugular venous pressure curve. Order of events?

Answer 34

Atrial contraction, closure of tricupsid valve, atrial relaxation (as ventricle is contracting), increased venous blood flow, filling ventricle (atria to ventricle) passively

Question 35

What are the common features of constrictive pericarditis on CT?

Answer 35

Calficiation and thickening of the pericarditis to greater than 4mm

Question 36

What are the side effects of all nitrates (both short and long acting)

Answer 36

Headaches and cutaneous flushing due to vasodilation

Question 37

What is the codon that signals initiation of protein synthesis?

Answer 37

AUG

Question 38

Coffee ground emesis suggests what?

Answer 38

Brisk upper GI bleed = Presecent of blood in the vomit that has been exposed to gastric acid

Question 39

Which antiarrythmics cause QT prolongation?

Answer 39

IA, and III. Amiodarone is unique in that it is not a/w increased risk for Torsades de Point as the rest are.