[Six-month short course chemotherapy containing pyrazinamide for initial treatment of pulmonary tuberculosis]

From January 1991 to December 1992, 419 patients with pulmonary tuberculosis were initially treated at Fukujuji Hospital. Among them, 190 patients, who were younger than 80 years old and had pulmonary tuberculosis with cavities or infiltration of extension 2 or 3, and/or were sputum-smear positive, had been treated by 6-month short course regimen containing pyrazinamide, 2HRS(E)Z/4HRE. And were eligible for the evaluation of the clinical usefulness of pyrazinamide-containing regimen for the initial treatment of pulmonary tuberculosis. The dose of pyrazinamide was 1.2 g per day irrespective of body weight. The patients of this treatment group consisted of 151 males and 39 females, and mean age of the males was 45.3 and that of the females was 43.8 years old. At the start of the treatment, 74% of the cases were smear positive, 70% were cavitary, and 6 cases each showed primary resistance to isoniazid and to streptomycin, respectively, and only one case showed resistance to both of isoniazid and streptomycin. There was no primary resistant case to either rifampicin or ethambutol. Bacteriologic negative conversion rates were 95% and 90% after 2 months of treatment by PZA-containing regimen and by the standard regimen, respectively, and treatment durations required to achieve the negative conversion of all cases were 3 and 6 months for respective regimens. Of 90 patients who completed 6-month PZA-containing regimen and could be followed-up, only one bacteriologic relapse (1.1%) was noticed. Elevation of serum GPT level higher than 150 IU/ml during the treatment was noticed in 6.3% of 175 cases under PZA-containing regimen in comparison with 4.0% of 174 cases under the standard regimen (not significant). The interval between the onset of the treatment and the detection of abnormal liver function was much shorter (mean 31.3 days) in the PZA-containing regimen than in the standard regimens (mean 63.4 days). Hyperuricaemia (> 10 mg/ml) was noticed in 46.7% of 57 males and 59.4% of 19 females tested, but pyrazinamide was not discontinued in any case due to arthralgia. These results clearly show that pyrazinamide can be used rather safely for Japanese tuberculosis patients. If the pyrazinamide-containing regimen [2HRS(E)Z/4HRE] is adopted as the new standard regimen in place of on-going standard regimen in Japan, 6HRS(E)/3HR, the duration of chemotherapy could be shortened by three months with the same level of both efficacy and safety. We recommended pyrazinamide-containing 6-month regimen, 2HRS(E)Z/4HRE, as the new standard regimen for the initial treatment of pulmonary tuberculosis.