Abstract:

Objectives: The aim of the present study was to evaluate the efficacy (recovery rate, time to detection and Drug Susceptibility Tests –DST- of Mycobacteria-only B460) of new colorimetric medium, Dio-TK and to compare it with routinely used conventional media, Lowenstein Jensen (LJ) and Bactec 460 TB culture system. Materials and methods: Totally 901 clinic specimens were investigated for assignment of tuberculosis by Ehrlich-Ziehl-Nielsen smear strain method, Lowenstein-Jensen, BACTEC 460TB and Dio-TK medium culture systems. Results: Nineteen of 901 clinic specimens (2.1%) were positive by any of these methods. 17 (89.5%) of these specimens positive found by smear strain method, 17 (89.5%) by Lowenstein-Jensen, 19 (100%) by BACTEC 460TB and 14 (73.7%) by Dio-TK medium. NAP and Niacin identification tests were applied to Mycobacterium strains. 12 (63.1%) of 19 isolates were identified as M.tuberculosis complex and 7 (36.9%) were identified as Mycobacterium other than tuberculosis (MOTT) bacilli. 10 (83.3%) of 12 M.tuberculosis complex strains were not resistant to any major drug. But one of 2 isolate was resistant to streptomycin and the other one isolate was resistant to both streptomycin and isoniazid. Conclusion: Our data suggest that some advantages (such as an early detection and differentiation mycobacterium growth from contamination) of the Dio-TK CS over other mycobacterial culture systems make it a practical and rapid system for daily use, and a suitable alternative to other currently available solid media, such as LJ, for detection time of mycobacteria and DST.

Keywords: