Beri-beri is

Correct Answer: A

Rationale: The correct answer is A because Beri-beri is indeed a disease caused by a deficiency of thiamine, endemic in eastern and southern Asia, and characterized by neurological symptoms, cardiovascular abnormalities, and edema. This is the classic definition of Beri-beri. Choice B is incorrect because it describes angular stomatitis, which is caused by a deficiency of riboflavin, not thiamine as in Beri-beri. Choice C is incorrect because it describes cheilosis, a disorder of the lips associated with riboflavin deficiency, not thiamine deficiency as seen in Beri-beri. Therefore, the correct answer is A as it aligns with the classic presentation and etiology of Beri-beri.

Correct Answer: B

Rationale: The correct answer is B: Sulfinpyrazone. This drug is an uricosuric agent that works by increasing the excretion of uric acid in the urine, thereby reducing serum uric acid levels. Allopurinol (A) is a xanthine oxidase inhibitor that decreases uric acid production. Colchicine (C) is used for gout but does not directly impact uric acid levels. Indomethacin (D) is a nonsteroidal anti-inflammatory drug that can help with gout symptoms but does not affect uric acid excretion.

Correct Answer: D

Rationale: The correct answer is D, as hypocalcemia in adults can result from various causes. Hypoparathyroidism leads to decreased parathyroid hormone and calcium levels. Vitamin D deficiency impairs calcium absorption. Renal failure and malabsorption can disrupt calcium balance. Therefore, all options A, B, and C contribute to hypocalcemia in adults. Other choices are incorrect because they do not comprehensively cover the major causes of hypocalcemia in adults.

Correct Answer: A

Rationale: The correct answer is A: Osmotic diuretics. Osmotic diuretics are the least potent diuretics as they work by creating an osmotic force that prevents water reabsorption in the nephron, leading to increased urine output. Loop diuretics (B) are more potent as they act on the ascending loop of Henle. Thiazide diuretics (C) are also more potent as they act on the distal convoluted tubule. Potassium-sparing diuretics (D) are relatively less potent than loop and thiazide diuretics but are still more potent than osmotic diuretics.

Correct Answer: B

Rationale: The correct answer is B: Pancytopenia. Chloramphenicol is known to cause bone marrow suppression, leading to a decrease in red blood cells, white blood cells, and platelets. This results in pancytopenia, which can manifest as anemia, increased risk of infections, and easy bruising or bleeding. Nephrotoxicity (A), hepatotoxicity (C), and ototoxicity (D) are not common side effects of chloramphenicol. Pancytopenia is a well-documented adverse effect of this antibiotic due to its impact on bone marrow function.