Resazurin microtiter assay for isoniazid, rifampicin, ethambutol and streptomycin resistance detection in Mycobacterium tuberculosis: Updated metaanalysis

Aims: The present meta-analysis aims to assess the evidence regarding the diagnostic accuracy and performance characteristics of the colorimetric redox indicator (CRI) assay with a special emphasis on the use of the resazurin microtiter assay (REMA) for determination of primary anti-tuberculosis drug resistance. Subject and methods: By updating previous literature searches in Medline PubMed, ISI Web, Web of Science and Google academic databases of the REMA test for determination of primary anti-tuberculosis drug resistance, this meta-analysis includes 14 studies for isoniazid (INH); 15 studies for rifampicin (RIF); 6 studies for streptomycin (STR); and 5 studies for ethambutol (EMB). SROC curve analysis was performed for meta-analysis and diagnostic accuracy was summarized. Results: Pooled sensitivity was 96% (94–98%) for INH, 97% (95–98%) for RIF, 92% (87–96%) for EMB and 92% (88–95%) for STR. Pooled specificity for INH, RIF, EMB and STR was 96% (95–98%), 99% (98–99%), 86% (81–89%) and 90% (87–93%), respectively. Susceptibility testing results had been obtained in 8–9days. Conclusion: In conclusion, REMA seems to be a reliable test for the determination of multi-drug resistant (MDR) isolates in laboratories with limited resources. However, few studies for STR and EMB have been found, and cost-effectiveness studies need to be determined to recommend its widespread use.