AND ANSWERS L 2025/2026 LATEST COMPLETE
EXAM (usmle step 1)MEDICAL EXAMINATION
66yo M with stage IV colon cancer with 3-day hx of severe diarrhea after receiving
chemotherapy with fluorouracil, leucovorin, and Irinotecan. prescribed opioid
antidiarrheal agent with no CNS effects. Which med?
Loperamide
35yo M in ED with 2-hour hx of sever fatigue and dizziness. Had profuse, watery
diarrhea for 8 hours despite a lack of oral intake. Recently returned from a medical
relief trip to a remove village in Honduras. T 36.7 C, P 122/min, BP 90/50. PE
shows dry skin and decreased capillary refill. Stool for occult blood is negative;
,stool is gray and turbid. Gram stain shows gram-negative, comma-shaped bacteria;
no erythrocytes of leukocytes. MOA of toxin?
Activation of adenylyl cyclase
59yo F with gradual onset of lack of muscle control in her left arm and leg. Sx 1
mo ago after dx with metastatic breast cancer. PE shows ataxia of left upper and
lower extremities. Muscle strength, DTR, sensation, proprioception normal.
Metastatic tumor in which location?
cerebellum
Newborn delivered at 38 weeks' gestation weighs 1800 g. PE shows petechial rash,
microcephaly, and hepatosplenomegaly. Serologic test for CMV: IgG + in mother,
+ in newborn; IGM - in mother, + in newborn. Explanation?
Congenital cytomegalovirus infection
Female newborn is delivered at 38 weeks' gestation. Apgar 8 and 8 at 1/5 min. PE
shows a bulging, fluod0filled mass approximately 5 cm in diameter in the midline
over the lumbosacral region. No spontaneous movements of the lower extremities.
Abnormality most likely occurred because of abnormal development during which
periods of postconception (in days)?
15 to 40
,AD
64yo M in ED 3 hours after SOB with exertion and extreme fatigue. Has ischemic
heart disease. P 125/min, BP 105/60. ECG shows atrial fibrillation. Intravenous
ibutilide is administered. Ten minutes later, ECG shows normal sinus rhythm. Risk
for which drug effect in the next 6 hours?
torsades de pointes
65yo F with 20-year hx of osteoarthritis of the hands now has pain radiating down
the distal anterior thigh, knee, medial leg, and food. Bony outgrowth of vertebrae
compressing one of the spinal nerves is suspected. Nerve root in which
intervertebral foramina is effected?
L3 to L4
38yo M with 3-year hx of T2DM. Taking an oral antihyperglycemic agent, he has
tried diet and exercise. BMI 32. PE normal. Hb A1c is 10%. Physician
recommends initiation of insulin injections. Responds, "I know that insulin would
help control my blood sugar. But a lot of people in my family have diabetes, and
insulin made them really sick at times. Patient is at which stage of change?
contemplation
24yo M with 2-day history of an itchy rash on his arms and legs. Returned from a
camping trip in the woods 5 days ago. PE shows edematous, erythematous rash
with linear vesicles. Cause is activation of which cell types?
T lymphocytes
, 70yo M from china with poorly differentiated monoclonal carcinoma of the
nasopharynx. DNA probes of neoplastic cells are most likely to detect genome of
which virus?
EBV
Epidemiologic study of aniline dye, 500 workers with bladder cancer and 200
workers without. Exposed to aniline dyes/Have Bladder cancer: Yes/Yes (250),
Yes/No (50), No/Yes (250), No/No (150). Odds ratio?
3
70yo M dies in a motor vehicle collision. Was undergoing evaluation for occult
blood in the stool. Photo of transverse colon shown. Dx?
Tubular adenoma
38yo M with 1-week hx of watery, itchy eyes and a runny nose. Physical shows
inflamed nasal mucosa. No congestion in lower lung. Pharmacotherapy?
Loratadine
16yo girl with 3-day hx of fever, nonproductive cough, and fatigue. T 38.3, P
88/min, BP 102-70. PE shows pale conjunctivae. CXR shows bilateral interstitial
infiltrates. Blood spontaenously agglutinates while awaiting transport to the
laboratory. Antibody isotypes causing agglutination?