Which of the following chemotherapeutic regimens are currently recommended for the treatment of pulmonary infection caused by M. tuberculosis?

C. Isoniazid and rifampin for 6 months with pyrazinamide added for the first two months.

E. Isoniazid and rifampin for 9 months. 

DISCUSSION: Treatment of tuberculosis with a single drug leads to rapid emergence of drug-resistant organisms. Any treatment regimen that employs only one drug for a period of time encourages the development of drug-resistant tuberculosis. Currently, the American Thoracic Society recommends either (1) a 6-month regimen consisting of isoniazid, rifampin, and pyrazinamide for 2 months followed by isoniazid and rifampin for 4 months or, alternatively, (2) a 9-month course of isoniazid and rifampin. Prolonged courses of treatment beyond 9 to 12 months no longer are considered necessary.