Review Question - QID 108658

The most likely diagnosis in this patient is acute gout. The patient is treated with colchicine, a medication used in the management of acute gout that inhibits microtubule polymerization and subsequently leukocyte migration and mitosis. GI upset is an important side effect of colchicine.

Acute gout occurs due to intra-articular deposition of monosodium urate crystals in the setting of hyperuricemia. Clinically, acute gout is characterized by excruciating joint pain and sensitivity, most frequently in the great toe. This patient has multiple risk factors for hyperuricemia including male sex, hypertension, thiazide diuretic use, alcohol abuse, and obesity. He is treated with colchicine, a medication used to treat acute gout. Colchicine inhibits microtubule polymerization by binding tubulin, effectively inhibiting leukocyte migration and mitosis. GI upset is the primary side effect of oral colchicine. Importantly, colchicine is considered a second-line medication in the management of acute gout. Non-steroidal anti-inflammatory medications (NSAIDs) and glucocorticoids are first-line.

Incorrect Answers:
Answer 2: Allopurinol is a first-line agent used to treat chronic gout that inhibits xanthine oxidase, thereby blocking the conversion of xanthine to uric acid. Its primary side effect is a rash.

Answer 3: Corticosteroids are a first-line agent in the treatment of acute gout. Steroids inhibit phospholipase A2-induced production of arachidonic acid, an upstream precursor of inflammatory prostaglandins and leukotrienes.

Answer 4: NSAIDs are often the first-line treatment of acute gout. NSAIDs inhibit cyclooxygenase-induced production of inflammatory prostaglandins. Indomethacin is the most commonly used NSAID in the treatment of acute gout. Similar to colchicine, NSAIDs can lead to GI upset but do not affect leukocyte migration or mitosis.

Answer 5: Rasburicase is a recombinant form of urate oxidase, an enzyme that metabolizes poorly soluble uric acid into the more soluble metabolite allantoin for easier excretion. It is used in the treatment of chronic gout if allopurinol is contraindicated.

Bullet Summary:
Acute gout is characterized by rapid-onset severe joint pain, most frequently in the great toe. Acute gout occurs due to buildup of intra-articular monosodium urate crystals. Colchicine is a medication used to treat acute gout that inhibits microtubule polymerization, thereby decreasing leukocyte migration and mitosis.