Standardisation and evaluation of DNA-lanthanide fluorescence spectroscopy for determining rifampicin resistance in Mycobacterium tuberculosis clinical isolates.

SETTING

Tuberculosis Research Centre, Chennai.

OBJECTIVE

To rapidly identify multidrug-resistant Mycobacterium tuberculosis using a novel method.

DESIGN

A new assay, based on DNA-lanthanide fluorescence, was standardised and evaluated using 93 each of coded rifampicin-resistant and rifampicin-sensitive M. tuberculosis clinical isolates for the correct identification of rifampicin resistance. The results obtained by the new assay were compared with the conventional results.

RESULTS AND CONCLUSION

The new assay gave a sensitivity and specificity of 88% and 85%, respectively. It is simple, easy to perform and requires 48 hours for the drug susceptibility results to be available after obtaining the primary culture.