MDR-TB treatment needs in patients previously treated for TB in Cotonou, Benin

Setting: Centre National Hospitalier de Pneumo-Phtisiologie, Cotonou, Benin. Objective: To determine the proportion of individuals needing treatment for multidrug-resistant tuberculosis (MDR-TB) among patients previously treated for TB. Design: A retrospective cross-sectional study of all patients previously treated for TB in Cotonou from 2003 to 2011. Results: Of 956 patients on retreatment, 897 (94%) underwent culture and/or a line-probe assay. For different reasons, 594 (66%) underwent drug susceptibility testing for rifampicin (RMP), of whom 95 (16%) had RMP resistance (68 multidrug-resistance [MDR] and 27 other RMP resistance) and therefore needed treatment for MDR-TB. These represent 39% of patients who failed/relapsed after standardised retreatment, and 20% of those who failed, 19% of defaulters and 11% of relapses after first-line treatment. Residence outside of Benin was associated with a higher risk of RMP resistance (RR 3.13, 95% CI 2.19-4.48, P < 0.01). From 2003 to 2011, the prevalence of RMP resistance decreased from 25% to 5% among patients living in Benin. Human immunodeficiency virus (HIV) prevalence was 25%; no association was found between HIV and RMP resistance. Of patients failing treatment, 48% were fully susceptible, 22% were monoresistant and 8% polyresistant. Conclusion: The majority of patients who fail retreatment or first-line treatment in Cotonou do not require empirical treatment for MDR-TB.