Comparison of redox and D29 phage methods for detection of isoniazid and rifampicin resistance in Mycobacterium tuberculosis

Abstract

Rapid, accurate and inexpensive methods are essential to detect drug-resistant Mycobacterium tuberculosis and allow timely application of effective treatment and precautions to prevent transmission. The proportion method, the MTT and Alamar Blue redox methods, and the D29 mycobacteriophage assay, were compared for their ability to detect resistance to isoniazid and rifampicin. When tested against a panel of known M. tuberculosis strains, the redox methods and the D29 assay showed good sensitivity and specificity compared to the proportion method, suggesting that they could be useful alternatives for identifying multidrug resistance in M. tuberculosis.

A simple and economical in-house phage technique for the rapid detection of rifampin, isoniazid, ethambutol, streptomycin, and ciprofloxacin drug resistance in Mycobacterium tuberculosis, directly on decontaminated sputum samples

“…Our findings were comparable with other studies for rifampicin1415172030, INH and or streptomycin12161821. In case of fluoroquinolones, only two studies reported phage assay1231, and information is scanty for ethambutol11.…”

IGF-I activates caspases 3/7, 8 and 9 but does not induce cell death in colorectal cancer cells

“…The fluorescence was measured with excitation at 530 and emission at 620 nm. Alamar blue assay is a redox method to measure the proliferation of various human and animal cell lines and has been proposed as an alternative method to MTT assay [21]. …”

Prevention of nosocomial transmission of extensively drug-resistant tuberculosis in rural South African district hospitals: an epidemiological modelling study

“…For phage-based assays, we simulated a turnaround time of 3 days [72][73][74][75][76][77][78][79][80][81][82], and 98% sensitivity (range 81 to 100%) and 93% specificity (range 73 to 100%) [79]. Line probe assays were simulated with a turnaround time of 3 days, and with 91% sensitivity (range 90% to 100%) and 96% specificity (range 91% to 100%) [83][84][85].…”