Rapid detection of multidrug-resistant Mycobacterium tuberculosis in Cotonou (Benin) using two low-cost colorimetric methods: resazurin and nitrate reductase assays.

We have evaluated two simple, rapid and low-cost colorimetric methods for the detection of multidrug-resistant Mycobacterium tuberculosis. A total of 151 M. tuberculosis strains were tested for resistance to rifampicin (RMP) and isoniazid by resazurin microplate assay (REMA) and nitrate reductase assay (NRA) in comparison with the conventional proportion method (PM) on Löwenstein-Jensen medium.