Rifampin in the Treatment of Drug-Resistant Mycobacterium tuberculosis Infections

Abstract

Thirty patients with far advanced, multiple-drug-resistant pulmonary tuberculosis were treated with rifampin for four to 12 months. The regimens included rifampin in a daily dosage of 600 mg combined, whenever possible, with one or more other antituberculosis drugs to which in vitro susceptibility had been demonstrated. Quiescent status was achieved in 21 (70 per cent) of the patients, whereas in nine (30 per cent) cultures remained positive, or the patient relapsed after having initially achieved sputum negativity. The shortest duration of rifampin therapy producing culture conversion was 10 days, and the longest 90 days, with a mean of 40. In seven of the nine failures rifampin resistance developed, and all but one of these patients received rifampin without a satisfactory companion drug because of previously acquired resistance. However, 65 per cent of the patients receiving rifampin as the sole therapy attained quiescent status; to date only two have relapsed. No toxicity attributable to rifampin was noted in this series.