Prevalence and Resistance Profiles of Drug-resistant Tuberculosis in the Southeastern Region of Nigeria

Abstract

Background and Aims: Drug-resistant tuberculosis (DR-TB) complicates tuberculosis control and requires accurate characterisation of resistance patterns to guide clinical and public health responses. This study investigated the prevalence and pattern of DR-TB among presumptive and follow-up tuberculosis patients in southeastern Nigeria. Study Design: A cross-sectional, multicentre regional epidemiological survey was employed. Place and Duration of the Study: The study was conducted across secondary and tertiary referral health facilities in Abia, Anambra, Ebonyi, Enugu, and Imo States, southeastern Nigeria, between January 2020 and December 2021. Methodology: Sputum specimens were collected from 217 presumptive and follow-up pulmonary tuberculosis (PTB) patients, comprising 144 males and 73 females. Sociodemographic data and clinical history were collected using structured clinical request forms (NTBLCP-02). Samples were screened using the GeneXpert MTB/RIF assay to detect Mycobacterium tuberculosis complex and rifampicin resistance (RR). All samples were thereafter subcultured on Lowenstein-Jensen media and subjected to line probe assay (LPA). Data were analysed using IBM SPSS version 27. Results: The prevalence of drug-susceptible TB was 14.3%, while mono-resistance to either rifampicin or isoniazid was 41.9%. Multidrug-resistant TB (MDR-TB) was detected in 36.4% of isolates, Pre-XDR TB in 4.1%, and XDR-TB in 3.2%. The resistance rates to rifampicin and isoniazid (first-line drugs) were 82.5% and 41.0%, respectively. The resistance rates to fluoroquinolones and aminoglycosides (second-line drugs) were 6.5% and 4.1%, respectively. There was no significant difference in the distribution of mono- and multidrug resistance across the states (p = .873). Conclusion: Drug-resistant tuberculosis presents a substantial public health threat in southeastern Nigeria, driven primarily by previous treatment exposure and incomplete regimen adherence. Expanding access to universal rapid molecular drug-susceptibility testing (DST) and second-line susceptibility testing is critical for curbing ongoing transmission and guiding targeted therapeutic strategies in the region.