Article

Multicenter evaluation of the nitrate reductase assay for drug resistance detection of Mycobacterium tuberculosis.

Mycobacteriology Unit, Institute of Tropical Medicine, Nationalestraat, 155, Antwerp, B-2000, Belgium.
Journal of Microbiological Methods (Impact Factor: 2.16). 12/2005; 63(2):145-50. DOI: 10.1016/j.mimet.2005.03.004
Source: PubMed

ABSTRACT The performance of the nitrate reductase assay was evaluated in a multicenter laboratory study to detect resistance of Mycobacterium tuberculosis to the first-line anti-tuberculosis drugs rifampicin, isoniazid, ethambutol and streptomycin using a set of coded isolates. Compared with the gold standard proportion method on Löwenstein-Jensen medium, the assay was highly accurate in detecting resistance to rifampicin, isoniazid and ethambutol with an accuracy of 98%, 96.6% and 97.9%, respectively. For streptomycin, discrepant results were obtained with an overall accuracy of 85.3%. The assay proved easy to be implemented in countries with limited laboratory facilities.

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