Primary drug resistance among Mycobacterium tuberculosis isolates from treatment naïve and new pulmonary tuberculosis patients in relation to their socio-economic status

Abstract

BACKGROUND: Multidrug-resistant Tuberculosis (TB) has become an area of growing concern throughout the World, despite the global efforts in eliminating TB. Detection of primary drug resistance in treatment naïve patients, either due to spontaneous mutation or due to transmission of drug-resistant strains is an important indicator of the presence of drug-resistant strains in the community.OBJECTIVES: The objective is to estimate the prevalence of primary drug resistance in treatment naïve pulmonary TB patients and to identify the socio-economic class of the resistant population.MATERIALS AND METHODS: A total of 272 treatment naïve presumptive TB patients were enrolled in the study from September 2018 to December 2020. The samples were subjected to GeneXpert, for detecting the presence of Mycobacterium TB (MTB) along with Rifampicin (RIF) resistance detection. Phenotypic drug susceptibility testing (DST) was performed on all positive mycobacterial cultures using the 1% proportion method against first-line anti-tuberculous drugs. Socioeconomic status of the patients was also assessed based on updated Kuppuswamy Socioeconomic scale (2018).RESULTS: Of the 272 samples subjected to GeneXpert MTB/RIF assay, MTB was detected in 193 (71%) samples and RIF resistance (rpoB gene) was detected in 25 (9%) samples. Phenotypic DST detected multidrug-resistant (MDR) in 22 (8%) samples. Majority of the MDR patients (55%) were belonging to the upper lower (IV) class of Kuppuswamy socio-economic scale.CONCLUSION: High prevalence of MDR-TB among treatment naïve pulmonary TB patients was noted in patients belonging to Class IV of Kuppuswamy socio-economic scale.