Repeated USMLE Questions Step 1 Review-163- Pharmacology

Q- A patient taking warfarin is given vitamin K. What is the primary effect of vitamin K administration? A- Decreases synthesis of clotting factors II, VII, IX, X B- Increases synthesis of clotting factors II, VII, IX, X C- Inhibits platelet aggregation D- Prevents fibrin degradation   Q- A patient taking spironolactone develops breast enlargement … Read more

Repeated USMLE Questions Step 1- Review-162

Q- A 2-year-old child has recurrent infections with catalase-positive organisms. Neutrophils show absent oxidative burst on flow cytometry. Which enzyme is defective? A- Adenosine deaminase B- Glucose-6-phosphate dehydrogenase C- NADPH oxidase D- Myeloperoxidase   Q- A patient has difficulty rising from a chair and climbing stairs. Biopsy shows endomysial inflammation and CD8+ T-cell infiltration. Which … Read more

Repeated USMLE Questions Step 1 Review-161- Pharmacology

Q- A patient receiving amphotericin B develops fever, chills, and renal dysfunction. What is the primary mechanism of nephrotoxicity? A- Afferent arteriole vasoconstriction B- Autoimmune tubular injury C- Direct glomerular inflammation D- Inhibition of prostaglandin synthesis A- Afferent arteriole vasoconstriction- Amphotericin B causes dose-dependent nephrotoxicity by constricting the afferent arteriole, reducing renal blood flow and … Read more

Repeated USMLE Questions Step 1- Review-160

Q- A patient with chronic kidney disease develops secondary hyperparathyroidism. Which of the following biochemical changes directly stimulates parathyroid hormone (PTH) secretion in this condition? A- Decreased 1,25-dihydroxyvitamin D levels B- Decreased serum phosphate C- Increased calcium-sensing receptor activation D- Increased intestinal calcium absorption   Q- A mutation prevents phosphorylation of the regulatory light chain … Read more

Repeated USMLE Questions Step 2 CK- Review- 52

Q- A 67-year-old man presents with sudden onset left arm weakness and facial droop that resolved completely within 30 minutes. CT scan of the head is normal. What is the most likely diagnosis? A- Intracerebral hemorrhage B- Ischemic stroke C- Subarachnoid hemorrhage D- Transient ischemic attack   Q- A 34-year-old woman presents with heat intolerance, … Read more

Repeated USMLE Questions Step 1 Review-157- Pharmacology

Q- A patient treated with cisplatin develops hearing loss. What is the mechanism of this adverse effect? A- Accumulation in cochlear hair cells B- Autoimmune inner ear inflammation C- Decreased cerebral perfusion D- Inhibition of prostaglandin synthesis   Q- A patient taking phenelzine develops severe hypertension after eating aged cheese. What is the underlying cause … Read more