Drug-resistance patterns and associated mutations of Mycobacterium tuberculosis strains isolated from chronic kidney disease and diabetes mellitus patients in Ethiopia

Abstract

Objective

To assess the drug-resistance (DR) patterns, mutations, and associated factors among tuberculosis (TB) cases identified from diabetes mellitus (DM) and chronic kidney disease patients.

Methods

The DR patterns of 77 Mycobacterial isolates were assessed using phenotypic drug-susceptibility testing, the Xpert MTB/rifampicin (RIF) assay, the Xpert MTB/XDR assay, and line probe assays. Data were analysed using SPSS version 27. Descriptive statistics, a chi-squared test, and logistic regression were conducted. The 95% CI was determined, and a P-value <0.05 was considered a statistically significant difference.

Results

Resistance pattern was determined for 76 Mycobacterial isolates, and one isolate had an invalid result. Any DR and multi-DR were detected among 25.0% (19), and 7.9% (6) isolates, respectively. Resistance to streptomycin, isoniazid (INH), RIF, ethambutol, and pyrazinamide was 11.8% (9), 13.2% (10), 10.5% (8), 6.6% (5), and 11.8%(9), respectively. Mono-DR was detected for streptomycin 3.9% (3), INH 2.6% (2), RIF 2.6% (2), and pyrazinamide 4.5% (4). One isolate was resistant to fluoroquinolones. Phenotypic and genotypic methods had concordant results in determining RIF and fluoroquinolones resistance. The common RIF and INH-resistant conferring mutations were observed at the S531L and S315T regions, respectively. Previous TB treatment and TB contact history were associated with DR-TB.

Conclusions

A quarter of TB cases identified had DR-TB, with a higher risk among patients with previous TB treatment history and had contact with TB patients, necessitating programmatic interventions, including applying infection prevention, contact tracing, and access to drug-susceptibility testing using rapid molecular methods.