Abstract:
Introduction – Tuberculosis is the most common cause of death due to single infectious agent
worldwide in adults. India alone accounts for 30% of global tuberculosis burden. There is
manifest need for method of cultivation of mycobacteria that is reliable, economical and has
short turnaround time.
Objective – Present study was attempted to assess the feasibility of using MB bact and
middlebrook7H10 as primary isolation medium for mycobacteria. It has been compared with LJ
medium, the gold standard.
Materials and Methods – Various clinical specimens from total of 230 clinically suspected
cases of TB were studied. All isolates were decontaminated using modified Petroff’s method.
Each sample was subjected to ZN staining and simultaneously inoculated onto LJ medium,
middlebrook7H10 medium and MB bact. Growth from the culture were confirmed by ZN
staining and speciated using biochemical reactions.
Results – Out of 230 samples screened, 116 isolates were obtained. Of the 116 all of them were
isolated from MB bact, 82 were isolated by LJ medium and 62 were isolated by
middlebrook7H10. 82 isolates were obtained by MB bact and LJ medium, 62 were obtained by
middlebrook7H10 and MB bact, 58 by LJ and middlebrook7H10 and 58 by LJ medium,
middlebrook7H10 and MB bact. Neither L J medium nor middlebrook 7H 1O medium could
isolate mycobacteria exclusively. The average isolation time by L J, middlebrook 7H10 medium
and MB BACT was 30.81 days,31.06 days and 18.70 days.
