Free Questions and Answers for All Medical Students all over the World
Q- A 64-year-old man presents to the emergency department with severe epigastric pain radiating to the back. He is febrile and tachycardic. Labs show lipase 1,800 U/L. RUQ ultrasound shows gallstones. Despite IV fluids and pain control, he develops hypotension and worsening hypoxemia over the next 12 hours. What is the best next step in … Read more
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
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
Q- A 67-year-old man with a history of chronic kidney disease presents with progressive shortness of breath and lower extremity edema. Echocardiography shows concentric left ventricular hypertrophy with normal ejection fraction. BNP is elevated. Which of the following pathophysiologic mechanisms is most responsible for this patient’s condition? A- Decreased myocardial contractility B- Impaired ventricular relaxation … Read more
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
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