NBME CBSE 200 QUESTIONS AND ANSWERS usmle step 1 MEDICAL EXAMINATION

NBME CBSE 2000 QUESTIONS AND ANSWERS (usmle step 1)MEDICAL EXAMINATION

NBME CBSE EXAM

Questions and Answers 200 Q & A

2026/2027 Newly Updated

Q: Male newborn at 28 weeks'. Given ventilatory support with up to 80% oxygen for the next

72 hours, but dies of resp. failure. Cause is inadequate secretion from which labeled cell types?

Answer:

D. type II pneumocyte (produces surfactant)

Q: 9yo girl with poor growth during the past year. < 3rd>

for weight. PE normal. Visual field testing shows bitemporal hemianopia. Labs show GH

deficiency. MRI shows calcified cystic mass in suprasellar region. Tumor derived from?

Answer:

Diverticulum of the roof of the embryonic oral cavity

Q: 28yo F G1P1 with 2-day history of a painful mass in her right breast. Delivered healthy

female newborn 3 weeks ago, and been breast-feeding since. T 37C, PE shows 3-cm tender mass

surrounded by an area of erythema beneath the right areola. Causal org?

Answer:

staph aureus

Q: 3yo boy with bacterial colitis caused by Salmonella enterica serovar arizonae. Which factor

accounts for recruitment of PMNS to inflammatory site by intestinal epithelial cells?

Answer:

IL-8

Q: 27yo F with fever, malaise, abdominal pain, and vaginal d/c for 4 days. LMP 5 days ago.

Had ectopic 1 year ago. T 38.3 C, bilateral lower quadrant tenderness with rebound and

guarding. Pelvic exam with cervical motion tenderness and bilateral adnexal tenderness WBC

18k. Pregnancy test neg. Dx?

Answer:

Gonorrhea (PID)

Q: 20M with 3-month hx of progressive thirst (drinking a lot of fluids) and urinary frequency

during past 3 days. U/A shows specific gravity less than 1.006. Most likely has dysfunction of

which endocrine structure?

Answer:

posterior pituitary gland (ADH)

Q: 21yo M in ED with excruciating anal pain for 4 hours. Exam shows 15-mm, blue tinged

rounded mass at anal margin. Represents thrombus in a tributary of which blood vessel?

Answer:

inferior rectal vein

Q: 6-week-old girl with 6-day hx of vomiting small amount of milk 2 to 3 times daily. 50%ile

for length and weight. Cause?

Answer:

Immature lower esophageal sphincter

Q: 37yo M with 4-day hx of diarrhea and abdominal pain, worse in past 24h, with waterybrown stools. Completed a 10-day course of amoxicillin for a sinus infection 5 days ago. Stool

shows: Fecal fat negative; ova and parasites negative; Cx for infx negative; C. Diff toxin

positive. Which pathologic findings present in intestinal tract?

Answer:

Pseudomemnbranes of fibrin and inflammatory debris

Q: 28yo M in ED 30 minutes after SOB. 3-year hx of cocaine abuse. T 38.1, P 100/min, BP

150/45. PE: diminished pulses in left upper extremity. Crackles heard over all lung fields. 2/6

diastolic murmur at left sternal border. CXr shows a widened aortic arch. Dx?

Answer:

Dissecting aneurysm

Q: 1-week-old girl. screening showed a possible defect in fatty acid oxidation. PE normal. Next

step?

Answer:

Measurement of serum acylcarnitine concentrations

Q: 79yoM 30 minutes after LOC for 30 seconds. Alert, but dizzy. No urinary or fecal

incontinence. Pulse 40/min, BP 92/56. PE shows no tongue biting. Lungs clear, Variable

intensity S1. Oriented X3. ECG shows a third-degree atrioventricular block. Next step?

Answer:

Insertion of transvenous pacemaker

Q: 55yo M with chronic bronchitis in ED after being unresponsive. Found bottles of albuterol,

ampicillin, codeine, and theophylline bedside. T 37.2 C, p 112/min, respirations are 6/min, BP

95/60. Acute Rx should include?

Answer:

naloxone