Effectiveness of Xpert MTB/RIF and the Line Probe Assay tests for the rapid detection of drug-resistant tuberculosis in the Central African Republic

• Published in: PLOS global public health 2023, Vol.3 (5), p.e0001847-e0001847
• Main Authors: Farra, Alain, Koula, Karen, Jolly, Boris Lokoti, Gando, Hervé Gildas, Ouarandji, Louis Médart, Mossoro-Kpinde, Christian Diamant, Manirakiza, Alexandre, Simelo, Jean Pierre, de Dieu Iragena, Jean
• Format: Article
• Language: English
• Subjects: Biology and Life Sciences; Medicine and Health Sciences
• ISSN: 2767-3375; 2767-3375
• DOI: 10.1371/journal.pgph.0001847

The Xpert MTB/RIF and Line Probe Assay (LPA) tests are more and more frequently used in mycobacteria testing laboratories for the rapid diagnosis of multi-drug resistance (MDR-TB). In this study, we demonstrate the effectiveness of these tests in the Central African Republic. Rifampicin resistance cases detected by the Xpert MTB/RIF during the year 2020 are also underwent first- and second-line LPA, and a first-line of drug susceptibility testing (DST) on solid medium and we compared these results. 101 rifampicin resistance cases based on the Xpert MTB/RIF were detected. Mean age was 34 years [16-81]. The 20-40 years age group represented 73.2% and the male-to-female sex ratio was 1.9:1. Patient profiles were dominated by treatment failure cases (40.6%) followed by relapsed cases (30.7%) and new cases (18.8%). These 101 rifampicin resistance were also detected with the first-line LPA and were confirmed by the DST. Similarly, the isoniazid results obtained with the first-line LPA, were confirmed by the DST, giving a concordance of 100% for these antibiotics. Rifampicin resistance were for the most part due to the absence of the WT8 sequence (56%) and the presence of the Mut3 mutation (53.4%). The majority of the isoniazid resistance (94.2%) were due to the Mut1 mutation in the katG gene and 4.2% of the cases involved both the katG gene and the inhA gene promoter with the Mut1 mutation. The second-line LPA test no resistance to second-line antibiotics. This study demonstrated the effectiveness of the Xpert MTB/RIF and the LPA tests for the rapid diagnosis of MDR-TB in the Central African Republic. However, due to their high cost, these tests have not been extensively deployed in the country. Public authorities and their TB-partners can help make these molecular tests more accessible to fight MDR-TB in the country.