Importance of Detection of Isoniazid and Rifampicin Mono Drug Resistance and Determining Rate of MDR-TB in Smear Positive Sputum Samples from a Tertiary Care Hospital of West U.P. India

Abstract

Anti-tubercular therapy is one of the effective strategies used to control tuberculosis, so, a planned and accurate treatment regimen is of utmost importance, but number of cases are being treated as MDR on the basis of rifampicin mono resistance. As reported earlier in various studies from India, prevalence rate of Multi Drug Resistant-Tuberculosis (MDR-TB) vary from region to region. Therefore, we set out to determine rate of MDR-TB, Isoniazid and Rifampicin Mono resistance and common mutation pattern associated with them from our area using GenoType MTBDR plus assay in order to provide better patient care and reduce rate of MDR-TB. This was a Cross-sectional study comprising of 1100 sputum samples collected from DOTS Centre and processed by ZN staining and LPA. Out of 1100 sputum samples, 203 were smear positive. In 203, 193 were detected as positive for MTBC. Rate of MDR was found 12.8% and rifampicin and isoniazid mono-resistance was 6.4% and 8.3% respectively. Commonest mutation pattern seen was S531L in rifampicin and S315T1 in isoniazid. Association between treatment history and resistance pattern was found to be statistically significant. We found there is a high rate of INH mono resistance which was not being detected till now from this area and we also found, there is unrelated risk of isoniazid and rifampicin mono-resistance so, inference of MDR based on RIF mono-resistance is also an inaccurate strategy to manage patients and drug sensitivity should be performed for both first line drug before stating MDR.