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Safety of pyrazinamide-including regimen in late elderly patients with pulmonary tuberculosis: A prospective
Eri Hagiwara1, Yoshihiro Suido1, Masato Asaoka1
1Department of Respiratory Medicine, Kanagawa Cardiovascular and Respiratory Center, 6-16-1 Tomioka-higashi, Kanazawa-ku, Yokohama, 236-0051, Japan.
Abstract:
Pyrazinamide (PZA) -including regimen had not been fully recommended for late elderly patients with tuberculosis (TB) by Japanese Society for Tuberculosis until 2018. Studies on the safety of adding PZA to other first-line TB drugs for late elderly patients are limited. In this prospective randomized open-label study, we aimed to assess the safety of regimen including PZA for patients aged 80 or older. Patients in their eighties with smear-positive pulmonary TB without any liver diseases were randomly assigned to HRE (isoniazid, rifampicin, ethambutol) group or HREZ (HRE and PZA) group. The primary endpoint was discontinuation or interruption rate of treatment due to liver injury. Other endpoint included overall rate of liver injury, time to culture conversion, and overall mortality. Eighty-nine patients were assigned to either HRE group (n = 45) or HREZ group (n = 44). Clinical background was not different in two groups including age, smear grade, body weight, serum albumin, and activity degree. Discontinuation of treatment due to liver injury occurred in 15.6% of HRE group and 9.1% of HREZ group, which showed no statistical difference. Incidence of liver injury was also comparable between two groups. Overall mortality was statistically higher in HREZ group (3 in HRE vs. 10 in HREZ), although all deaths seemed to be irrelevant to PZA use. Time to culture conversion was significantly shorter in HREZ group (43.6 days vs. 30.2 days). In conclusion, regimen including PZA seems to be safe for late elderly patients with pulmonary TB.
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