title: Comparison of rapid colorimetric method with conventional method in the isolation of Mycobacterium tuberculosis.
abstract: The aim of the study was to evaluate two methods (colorimetric and conventional) for isolation of Mycobacterium tuberculosis. A total of 500 clinical specimens were processed by modified Petroff's method and then inoculated into MB/BacT-240 system bottles and on LJ medium slopes. The specimens included 242 sputum, 95 gastric aspirates, 47 pleural fluids, 45 CSF, 32 urine, 18 pus, 11 bronchoalveolar lavage, 3 tissue, 2 stool, 2 lymphnode specimens, 2 synovial fluid and 1 bronchial wash specimens. The isolation rate was 16.4% by the colorimetric method and 2.2% by the conventional method. The mean detection time was 16 days and 26 days respectively. Among 36 direct smear positive samples, 63.9%(23/36) and 30%(11/36) were positive by colorimetric and conventional methods respectively. Out of 464 direct smear negative samples 12.9%(60/464) and 0.6%(3/464) were positive by colorimetric and conventional methods respectively. Therefore, colorimetric method enables rapid detection leading to early diagnosis and drug susceptibility testing.
authors.affiliation: Department of Microbiology, Christian Medical College and Hospital, Ludhiana - 141 008, Punjab, India.
authors.forename: A
authors.initials: A
authors.lastname: Oberoi
authors.forename: H
authors.initials: H
authors.lastname: Kaur