title: Rapid Detection of Rifampicin and Isoniazid Resistant Mycobacterium tuberculosis Using Genotype MTBDRplus Assay in Nepal.
abstract: Rapid line probe assay (LPA) can be a practical and rapid alternative to the slow conventional phenotypic drug susceptibility testing (DST) for detection of drug resistant tuberculosis (TB). The purpose of this study is to determine the diagnostic accuracy of Genotype MTBDRplus, LPA for TB, and compare its performance with conventional DST. A total of 54 culture samples were analyzed for DST using both conventional proportion method and MTBDRplus, where conventional DST identified 43 isolates (79.6%) as drug resistant. Among these 43 drug resistant isolates, 30 isolates (69.7%) were found to be multidrug resistant (MDR). Of all observed mutations using MTBDRplus, codon 531 of rpoB gene and codon 315 of katG gene were found to have highest mutational frequency for RIF resistance (64.7%) and INH resistance (96.8%), respectively. In the present study, MTBDRplus assay was shown to have excellent specificity (100%) for both RIF and INH resistance while sensitivity of the assay was little lower with value of 89.4% for RIF resistance and 91.4% for INH resistance. Therefore, the assay can be a rapid, reliable, and promising molecular test for early detection of MDR-TB in Nepal.
authors.affiliation: Central Department of Microbiology, Tribhuvan University, Kathmandu, Nepal.
authors.forename: Bijay Kumar
authors.initials: BK
authors.lastname: Sharma
authors.affiliation: Central Department of Microbiology, Tribhuvan University, Kathmandu, Nepal.
authors.forename: Shiva
authors.identifier: 0000-0001-7276-995X
authors.initials: S
authors.lastname: Bhandari
authors.affiliation: German Nepal Tuberculosis Project (GENETUP), Kathmandu, Nepal.
authors.forename: Bhagwan
authors.identifier: 0000-0002-1913-635X
authors.initials: B
authors.lastname: Maharjan
authors.affiliation: German Nepal Tuberculosis Project (GENETUP), Kathmandu, Nepal.
authors.forename: Bhawana
authors.initials: B
authors.lastname: Shrestha
authors.affiliation: Central Department of Microbiology, Tribhuvan University, Kathmandu, Nepal.
authors.forename: Megha Raj
authors.identifier: 0000-0002-5024-6127
authors.initials: MR
authors.lastname: Banjara