Chemotherapy of pulmonary tuberculosis. Sputum culture conversion in 8 weeks in 84% of patients

Conversion rate to negativity of sputum culture and microscopy in 50 patients, previously untreated, with open cavernous pulmonary tuberculosis was analysed. Treatment consisted of isoniazid, rifampicin and pyrazinamide for three months, followed by administration of isoniazid and rifampicin. Conversion to a negative sputum culture had occurred after four weeks in 30% of patients, after eight weeks in 84%, and after 14 weeks in all patients. In 76% of patients the cultural conversion preceded the microscopic one. Treatment was well tolerated; only one patient had side effects requiring a short interruption of drug administration. The results confirm that this regimen is effective against pulmonary tuberculosis without significant side effects.