Evaluation of Culture Methods for Isolation of Mycobacterium tuberculosis Complex and Its Resistance among Pulmonary Tuberculosis Cases in a Tertiary Care Setting, Kerala - A Pilot Study
Year: 2018
Type: article
Abstract: Tuberculosis is an important public health problem in India and globally. Prompt detection and susceptibility testing of Mycobacterium tuberculosis complex from clinical specimens is essential for appropriate management of patients with tuberculosis. With this in background, this study aimed at the comparison of isolation of Mycobacterium tuberculosis complex from clinical specimens of patients suspected of pulmonary tuberculosis using BACTEC Micro MGIT and Lowenstein Jensen (LJ) media with detection of resistance. A prospective study was carried out for one year from November 2016 to October 2017 in the Department of Microbiology, Pushpagiri Medical College, Tiruvalla, Kerala. A total of 81 samples were processed for Ziehl-Neelsen (Z-N) staining and was then cultured using liquid Mycobacterium growth indicator tube (BDTM BACTECTM Micro MGIT) and solid (Lowenstein Jensen’s) media. Isolates confirmed as Mycobacterium tuberculosis complex were subjected to drug susceptibility testing (DST) using modified proportion method by MGIT for 1st line drugs i.e. streptomycin (1.0µg/ml), isoniazid (0.1µg/ml), rifampicin (1µg/ml), ethambutol (5µg/ml) and pyrazinamide (100µg/ml). Of the total 81 samples that were cultured, seven (8.6%), were positive by both MGIT and Lowenstein Jensen’s. Three (3.7%) were positive by MGIT only and not by LJ. Only 4/10 (4.9%) culture positive samples were positive by direct smear examination. Turnaround times for culture positivity by MGIT vs LJ was an average of 15.1 days vs 23.8 days. Sensitivity to all drugs was observed in 4/10 (40%) isolates. None of these 10 isolates were multidrug resistant. Culturing of the organism in addition to smear, increases the possibility of microbiological diagnosis and offers a possibility for drug susceptibility testing.
Authors: Sreeja Nair, Seema Oommen, Vidya Pai
Institutions: Pushpagiri Medical College, Yenepoya University
Language: English
Subfield: Infectious Diseases
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W2903390856