Evaluation of a rapid assay for detection of rifampicin resistance in my cobacterium tuberculosis; a microbiological, clinical and epidemiological study

ABSTRACT

The aim of the present study was to portray the clinical and epidemiological features of mycobacterium tuberculosis [MDR-TB] patients and to determine the ability of a commercial kit [fast plaque TB-RifTM test] to correctly identify, within 48 hours, rifampicin susceptibility on the strains of Mycobacterium tuberculosis cultured on solid media and compare it with a conventional method of susceptibility testing. Sputum specimens were collected from hospitalized patients with known or suspected pulmonary tuberculosis. They were examined microscopically after Ziehl-Neelsen staining. Specimens that were 1+ smear +ve were inoculated on LJ medium and incubated for eight weeks. Forty-five cultures were tested for rifampicin susceptibility, employing both the proportion and the fast plaque TB-RifTM test. The study concluded that fast plaque TB-RifTM test offers a performance comparable with the standard conventional method of rifampicin susceptibility testing. Furthermore, it has the advantage of quick results [within 48 hours] without the need for specialized equipment. This makes it a reliable rapid diagnostic tool in testing for rifampicin resistance and as an indicator of MDR in TB