Answers

1. C. Pyrazinamide is known to cause hyperuricemia and precipitate gouty arthritis. Pyrazinamide-induced gouty arthritis does not respond to urico-suric therapy with probenecid but may respond to acetylsalicylic acid. Cycloserine (A) can cause headaches, confusion, tremors, and seizures, possibly secondary to low levels of magnesium in the cere-brospinal fluid; cycloserine should be avoided in patients with epilepsy and mental depression. It is not associated with hyperuricemia. Thiacetazone (B) is an antibiotic that is rarely used in tuberculosis. The most common adverse reactions are general rashes and GI intolerance. Its use is not associated with hy-

peruricemia. Rifampin (D) is associated with hepatitis, GI intolerance, drug interactions and a red-orange discoloration of saliva, tears, and urine. It is not associated with hyperuricemia. Aminosalicylic acid (E) is sometimes associated with sodium overload and fluid retention when large doses of the sodium salt of PAS is administered; it is not associated with hyperuricemia.

2. A. Ethambutol is associated with retrobulbar neuritis, resulting in loss of central vision and impaired red-green discrimination. Ethionamide (B) is an analogue of isonicotinic acid and is associated with GI intolerance and peripheral neuropathy, but not the optic neuritis or color vision discrimination problems. Aminosalicylic acid (C) can cause GI irritation and bleeding problems, so caution is required in peptic ulcer patients. It has no neurological side effects. Rifampin (D) is associated with red-orange discoloration of saliva, tears, and urine but not the color vision problems. Isoniazid (E) is associated with peripheral neuritis in chronic alcoholics and malnourished individuals and requires pyridoxine supplements. It is not associated with optic neuritis.

3. C. Clofazimine has antilepromatous and antiinflam-matory properties. Its most disturbing side effect is red-brown pigmentation of skin, particularly in light-skinned persons. Dapsone (A) can produce rashes and erythema nodosum, including StevensJohnson syndrome (dapsone dermatitis), but it is not associated with altered skin pigmentation. Rifampin (B) imparts a harmless red-orange discoloration of saliva, sweat, urine, feces, tears, and contact lenses but is not associated with skin pigmentation changes. Capreomycin (D) is similar to streptomycin and can cause ototoxicity and nephrotoxicity. Its use is not associated with skin discoloration or pigment problems. Thiacetazone (E) is rarely used in the treatment of leprosy. Rashes and GI intolerance are common side effects. It is not associated with any skin discoloration or pigment problem.

4. E. Rifampin, commonly used in the prophylaxis of Neisseriae meningitidis, is given to individuals who are in close contact with someone having the disease. Other drugs that can be used include ciprofloxacin and sulfonamides. Amoxicillin (A) is used as prophylaxis of endocarditis in patients with a history of endocarditis or a preexisting valvular heart disease. Isoniazid (B) is a commonly used drug for latent tuberculosis infection in high-risk patients who are positive PPD and have a negative chest radiograph. Dapsone (C) is used as a chemoprophylactic agent for Pneumocystis carinii pneumonia in AIDS patients who are allergic or intolerant to trimethoprim-sulfamethoxazole. Clarithromycin (D) is used as a chemoprophylactic agent for MAC in AIDS patients.

5. C. Cycloserine is associated with confusion, psychosis, and suicidal ideation; symptoms are usually seen within a week of therapy. Cycloserine should be avoided in patients with psychiatric disorders. Pyrazinamide (A) is associated with a hepatic dysfunction that must be closely monitored. Nearly all patients taking pyrazinamide develop hyper-uricemia. It has no neurological side effects. Aminosalicylic acid (B) is associated with GI intolerance, especially acute bleeding, due to severe gastritis. It has no neurological side effects. Rifampin (D) is associated with hepatitis, drug interactions, red-orange discoloration of body fluids, and rarely, a flulike syndrome. It has no neurological side effects. Ethambutol (E) is associated with retrobulbar neuritis and color vision impairment. It may cause peripheral neuritis but is not associated with behavioral problems.

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