GENOTYPIC CHARACTERISTICS AND MOLECULAR MARKERS OF ANTIBIOTIC RESISTANT NONTUBERCULOUS MYCOBACTERIA AND ASSOCIATED CLINICAL OUTCOMES AMONG PATIENTS ATTENDING BUNGOMA COUNTY, KENYA

Abstract

Free-living, saprophytic non-tuberculous mycobacteria (NTM) are widely distributed and mostly found in sediment, aquatic habitats, biofilms, aerosols, animals, and people. M. tuberculosis (MTB) and NTM are both members of the Mycobacterium genus. It could display similar microscopic, radiological, and clinical features as MTB. Studies have reported 33.4% of cases are in North America, 23.8% are in Europe, 20.8% are in Asia, and 7.5% are in Africa. Worldwide, non-tuberculous mycobacterial infection prevalence varies. Currently, NTM infections and the rising incidence of antibiotic resistance (AMR)are the two major global health issues are. A significant prevalence of 33.6% for MTB among HIV patients have been reported in Kenyan counties like Bungoma. This study examined the antibiotic susceptibility profiles and genotypic traits of NTM isolates from people living with HIV (PLWH) at Bungoma County Referral Hospital (BCRH). This study assessed the relationship between AMR molecular markers and clinical outcomes such underweight status, immunosuppression, and viral suppression. A total of 167 suspected TB patients were selected purposively in an analytical cross-sectional study. Smear microscopy and culture were used to determine presence of NTM, while ELISA determined HIV status. The Abbott m2000 system was used to establish viral load and flow cytometry was used to measure CD4+ T cell count, and NTM infection. While NTM isolates' minimum inhibitory concentrations were assessed using microdilution broth, NTM species in positive cultures were identified using the Hain Genotype Mycobacterium CM/AS assay. Continuous data were analysed using the Mann-Whitney U test, while categorical variables were compared using chi-square testing. Using logistic regression and Pearson correlation, the relationship between AMR in NTM isolates and clinical outcomes among PLWH was evaluated. PLWH had a 41.1% prevalence of positive NTM cultures, whereas HIV-negative individuals had a 21.3% prevalence (P = 0.280). The most common species was M. intracellulare (42.9%), which was followed by M. fortuitum (26.3%). Less often found were M. lentiflavum, M. scrofulaceum, and M. abscessus. Drug-resistant NTM isolates from PLWH and HIV negative individuals showed resistance to pyrazinamide (15.2% vs. 4.3%, P<0.001), ethambutol (9.1% vs. 0.0%, P < 0.001), and isoniazid (12.1% vs. 8.7%, P < 0.043). HIV-negative individuals had a median CD4+ T cell count of 853 cells/mm³, whereas PLWH had a median of 454 cells/mm³. In 9.6% and 3.2% of PLWH cases, respectively, the presence of the rpoB and katG genes was associated with AMR. In HIV-negative individuals’ the prevalence of mutations in the inhA gene were 2.1%, while PLWH had a 2.7% prevalence. PLWH co-infected with inhA-carrying NTM had a twofold increased risk of underweight (OR: 2.409, 95% CI: 1.858-7.871; P = 0.040). The rpoB and katG genes were not associated with outcomes like underweight, viral load, or immunosuppression. The study's findings highlight how common AMR is in NTM isolates from PLWH, which has significant implications for therapeutic treatment. In addition, mutations in the inhA gene were associated with a higher risk of underweight status in PLWH. Therefore, there is need of molecular surveillance as well as addressing educational and vocational variables in the management of AMR among PLWH in Bungoma County.