Application of the resazurin microtitre assay for detection of multidrug resistance in Mycobacterium tuberculosis in Algiers.

This study assessed the performance of a rapid, low-cost, colorimetric method, the resazurin microtitre assay (REMA) plate method, for the detection of resistance to isoniazid and rifampicin in 136 clinical isolates of Mycobacterium tuberculosis from two hospitals in Algiers. MICs were determined and the results were compared with those obtained with the conventional proportion method on Löwenstein-Jensen medium. Excellent results were obtained for the REMA plate method, with a sensitivity of 100 % for both isoniazid and rifampicin and a specificity of 98.3 and 99.2 %, respectively. The REMA plate method appears to be a reliable method for the rapid determination of multidrug-resistant tuberculosis and is a good alternative for use in resource-limited countries such as Algeria.