Comparative evaluation under routine conditions of the nitrate reduction assay, the proportion assay and the MGIT 960 assay for drug susceptibility testing of clinical isolates of Mycobacterium tuberculosis.
The performance of the nitrate reductase assay (NRA) was compared with the proportion method (PM) on Lowenstein-Jensen medium and the BACTEC MGIT960 assay under routine conditions using 160 clinical isolates of Mycobacterium tuberculosis with a high proportion of resistant strains. The mean time to obtain results was 8.8 days and the overall agreements between NRA and PM and NRA and M960 were 95% and 94%, respectively. NRA was easy to perform and represents a useful tool for the rapid screening of drug-resistant M. tuberculosis strains in low-resource countries.
Laboratório de Micobacteriologia, Complexo Hospitalar Instituto de Doenças do Tórax/Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Brasil. lsfonseca@micro.ufrj.br
Leila de Souza
Lde S
Fonseca
Gisele Betzler de Oliveira
GB
Vieira
Luciana Fonseca
LF
Sobral
Elizabete Oliveira
EO
Ribeiro
Anna Grazia
AG
Marsico
D000995:Antitubercular Agents / Q000494:pharmacology*; D003470:Culture Media / Q000494:pharmacology*; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods*; D009169:Mycobacterium tuberculosis / Q000187:drug effects*; D050901:Nitrate Reductase / Q000494:pharmacology*
D000995:Antitubercular Agents; D003470:Culture Media; D050901:Nitrate Reductase