Isoniazid-resistant tuberculosis in Iran: A systematic review

Isoniazid (INH) is one of the most potent anti-tuberculosis (TB) agents. INH resistance is an obstacle to the treatment of TB disease and the National TB control Program (NTP). We aimed to determine the true prevalence of INH-resistant TB in Iran. Several databases including Embase, Medline, Cochrane library and Iranian databases were searched to identify studies addressing INH-resistant tuberculosis in Iran. We identified 156 articles, of which 129 records were excluded based on their titles and abstracts. In a secondary screening, we assessed the eligibility of 27 full-text articles of which, 6 did not report usage data. Finally, 21 studies published from different regions of Iran from March 1999 until July 2015 were included in this study. Comprehensive meta-analysis (V2.2, Biostat) software was used to analyze the data. The meta-analysis showed that 12.8% (95% CI 9.4-15.8; I2 = 87.8; P < 0.001 test for heterogeneity) of new TB cases and 40.1% (95% CI 28.5-53.0; I2 = 88.2; P < 0.001 test for heterogeneity) of previously treated cases were resistant to INH. High prevalence of INH resistance among TB patients has been reported in many health-care settings, suggesting that better management of such cases, use of effective treatment regimens and establishing advanced diagnostic facilities are needed to avoid further emergence of INH-resistant TB.