title: Standardization of first and second-line antitubercular susceptibility testing using BacT Alert 3D system: a report from a tertiary care centre in India.
abstract: Resurgence of multidrug resistant tuberculosis has lead to demand for rapid susceptibility testing. Conventional methods take > 3 weeks and are tedious. Automated methods have superseded them for first line drug susceptibility testing. An attempt was made to standardize first and second line susceptibility testing using the BacT Alert 3D system (Biomerieux). And compare results with Lowenstein Jensen's (LJ) method. 121 isolates of Mycobacterium tuberculosis, 67 pulmonary and 54 extra pulmonary were subjected to sensitivity to first and second line drugs. Multidrug resistance was detected equally by both methods at 15.7%. 100% agreement was observed between the two methods for aminoglycosides, rifampicin, ethionamide and ciprofloxacin. 91.5% agreement was observed for isoniazid, 85% for pyrazinamide and 72.4% for ethambutol. The time taken by LJ method was 18-32 days and BacT Alert 3D system took 4-12 days. In the lesser developed nations where tuberculosis is rampant a rapid effective method for confirming multidrug resistant tuberculosis is definitely desirable and the BacT Alert 3D system was found an effective method when compared to the 'gold standard' LJ proportion.
authors.affiliation: Department of Medical Microbiology, Safdarjung Hospital, Vardhman Mahaveer Medical College, New Delhi, India. deepthinair2@gmail.com
authors.forename: Deepthi
authors.initials: D
authors.lastname: Nair
authors.forename: Malini R
authors.initials: MR
authors.lastname: Capoor
authors.forename: Deepti
authors.initials: D
authors.lastname: Rawat
authors.forename: Lakshmi
authors.initials: L
authors.lastname: Srivastava
authors.forename: Pushpa
authors.initials: P
authors.lastname: Aggarwal
mesh_terms: D000995:Antitubercular Agents / Q000494:pharmacology*; D006801:Humans; D007194:India; D008826:Microbial Sensitivity Tests / Q000379:methods / Q000592:standards*; D009169:Mycobacterium tuberculosis / Q000187:drug effects* / Q000302:isolation & purification; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018088:Tuberculosis, Multidrug-Resistant / Q000188:drug therapy* / Q000382:microbiology
chemical_list: D000995:Antitubercular Agents