Drug-resistant tuberculosis profiles among patients presenting at the antituberculosis center of Brazzaville, Republic of Congo.

BACKGROUND: WHO strategy to end Tuberculosis (TB) calls for drug susceptibility testing of Mycobacterium tuberculosis (MTB) for all patients, in high TB burden settings. Thus, this study aimed to investigate the MTB drug resistance profiles and related risk factors among patients presenting to the Antituberculosis Center of Brazzaville, Republic of Congo.

METHODS: A cross-sectional study was carried out from July 2022 to August 2023 involving 1,121 presumptive pulmonary tuberculosis patients enrolled to the Antituberculosis Center of Brazzaville. Sputum samples were collected from all the study participants for the diagnosis of tuberculosis and rifampicin resistance, using the Xpert MTB/RIF (Cepheid, USA) assay. Samples positive for MTB with drug resistance to RIF were further tested for the second line anti-MTB drug susceptibility using the 10-color Xpert MTB/XDR assay.

RESULT: Out of 1,121 presumptive TB patients tested, 302/1,121 (26.9%) were MTB positive. Among these, 18/302 (6.0%) had received previous TB treatment and 15/302 (5.0%) were HIV co-infected. The mean age of the study population was 34 years, with a higher prevalence in males (69.2%). Of the MTB isolates, 25/302 (8.3%) were Rifampicin-resistant, with 24/25 (96%) further confirmed as multi-resistant strains, including 6/24 (25%) pre-XDR. Risk factors for MDR-TB included a history of TB treatment (AOR = 8.96, p = 0.002) and chronic cough (AOR = 7.14, p = 0.003).

CONCLUSIONS: This study reveals a high level of drug-resistant tuberculosis in Brazzaville, with previous TB treatment being a significant risk factor. The findings underscore the need to strengthen molecular surveillance and TB management and control measures in the Republic of Congo.