COMPARISON OF Geno Type MTBDRplus WITH BACTEC MGIT 960 FOR ISONIAZID AND RIFAMPICIN Mycobacterium tuberculosis DRUG RESISTANCE MONITORING IN HIV PREDOMINANT REGION OF WESTERN KENYA

Background: Globally, tuberculosis drug resistance is one of the leading poor clinical outcomes of treatment. Early detection of drug resistant strains is one of the tools that has been used in drug resistance monitoring and molecular line probe assays have been alternatives to phenotypic methods. Although there is evidence of the accuracy of the line probe assay for tuberculosis drug resistance monitoring, the prevalence of drug resistant tuberculosis varies regionally and this variation in prevalence has a significant impact on the predictive value of the line probe assay. As such this study aimed to evaluate the performance of line probe assay for detection of isoniazid and rifampicin Mycobacterium tuberculosis drug resistance in Human Immunodeficiency Virus endemic region of Western Kenya. Methods: In this prospective cross sectional study, the investigation evaluated the performance of GenoType MTBDRplus in detection of drug resistance. Using BACTEC MGIT 960 as the gold standard, sensitivity, specificity, positive predictive value and negative predictive value of the two assays were compared and the pattern of mutations associated with resistance to rifampicin and isoniazid analyzed. Results: GenoType MTBDRplus correctly identified isoniazid resistance 9/11 and rifampicin 7/10 and a statistical significant relationship with BACTEC MGIT 960 for detection of isoniazid and rifampicin resistance, p<0.05, area under the curve 0.909 and 0.85 respectively indicating an excellent diagnostic accuracy. Conclusion: Geno Type MTBDR plus assay was found to be consistent method for direct detection of resistance to isoniazid, rifampicin and multidrug resistance tuberculosis directly from sputum samples in HIV endemic regions of Western Kenya.