Drug Resistant Tuberculosis in the Northern Region of Zambia: A Retrospective Study

Background Zambia like many countries in sub-Saharan Africa is affected with drug resistant tuberculosis. However, the drug resistant tuberculosis situation over the years has not been described in various regions of the country. Consequently, this study aims to determine the drug resistant tuberculosis burden in northern regions of Zambia over a four-year period based on data generated from a Regional Tuberculosis Reference Laboratory. Method Two hundred and thirty two (232) Tuberculosis Drug Susceptibility Testing results over a four-year period (2016-2019) were reviewed. Data was collected from tuberculosis registers and patient request forms and entered into a pre-tested standardized checklist and later entered in Excel Computer software. Double blinded checking was done by two independent data clerks to minimize duplication of cases. Cleaned data was then imported in R programme for analysis. Bivariant and descriptive statistics were performed and reported. Results Of 232 Drug Susceptibility Testing results, 90.9% were drug resistant TB while 9% were drug susceptible. Fifty three percent (53%) of these were multi-drug resistant Tuberculosis and 32% were confirmed as Rifampicin Mono-resistance. Only 1.7% of the Multi-drug resistant Tuberculosis patients were Pre-extensively drug-resistant Tuberculosis. Copperbelt province had the largest proportion (46.0%) of multi-drug resistant tuberculosis patients followed by Luapula (8.1%) and North-Western (4.7%) provinces. In new and previously treated patients, the proportion of Multi-drug resistant tuberculosis was 71.8% and 28.7% respectively. History of previous anti-tuberculosis treatment and treatment failure were associated with multi-drug resistance TB. Conclusion and Recommendation This study has shown a small increase in the proportions of drug resistant tuberculosis cases over the four years under review with high rates being recorded on the Copperbelt Province. Previous treatment to first line TB treatment and treatment failure were associated with development of Multi-drug resistance. We therefore recommend strengthened routine laboratory surveillance and improved case management of multi-drug resistant tuberculosis patients in the region.