Background: The BACTEC MGIT 320 is a new, lower-capacity instrument for liquid culture developed for the growth and detection of M. tuberculosis and antimicrobial susceptibility testing. MGIT has an improved speed and sensitivity of MTB isolation and drug susceptibility testing, irrespective of the HIV status of the patient. This study was undertaken to find the appropriate antibiotic susceptibility pattern of confirmed positive MTB strains via MGIT 320 liquid culture technique. Objectives: Isolation of positive MTB strains and determination of their antibiotic susceptibility pattern using BACTEC 320 from the females of child bearing age group. Material and Methods: A total of 217 samples were processed involving the isolation of MTB strains along with the antibiotic susceptibility pattern of positive MTB’s. Both techniques were used culture and RT-PCR to find the prevalence and AST via BACTEC 320 system. Analysis of the results was done at the end of the procedure. Results: Out of 217 samples, there were 29 positive MTB strains by RTPCR technique whereas via liquid culture there were 11 positive MTB strains. The Antibiotic susceptibility pattern for MTB positive strains for both the first and second line was Levofloxacin, Kanamycin and PAS were found to be much sensitive whereas Isoniazid and Ethionamide were found to be more resistant than others. Conclusion: RT-PCR technique detects the total count of mycobacterial bacilli whereas via liquid culture only viable bacteria are detected i.e. true positive MTB strains. There were 2 MDR and 2 XDR TB detected, out of 11 confirmed MTB strains.

Keywords: AST; BACTEC 320; MTB Strains; RT-PCR Technique; Liquid Culture.