Original Article - Drug resistance profile of human Mycobacterium avium complex strains from India

Purpose: To determine minimum inhibitory concentration (MIC) of various anti-tuberculosis drugs for Mycobacterium avium complex (MAC) strains isolated from clinical samples. Methods: Forty-nine human isolates of MAC were tested for susceptibility to nine chemotherapeutic agents. All isolates were from Indian patients suffering from chronic pulmonary mycobacteriosis. Drug susceptibility was performed both by agar dilution and MIC method. MIC values were analysed, both visually and by enzyme-linked immunosorbent assay reader. Results: More than 40% of the MAC isolates were sensitive to ciprofloxacine (48.98%), amikacin (46.94%) and roxithromycin (42.86%) by the MIC method. In contrast, the isolates showed high degree of resistance to the first line antituberculosis drugs: only 28.6% were sensitive to rifampicine, 22.85% to isoniazid and ethambutol each and 36.7% were sensitive to streptomycin. In addition, 22.85% of the strains were sensitive to clofazimine and 34.7% to kanamycin. Conclusions: Results of the study confirm the suitability of the rapid broth micro dilution (MIC) method as a simple yet reliable method to assay for the drug susceptibility of nontuberculosis mycobacterium