Evaluation of BACTEC mycobacteria growth indicator tube (MGIT 960) automated system for drug susceptibility testing of Mycobacterium tuberculosis

Citation
F. Ardito et al., Evaluation of BACTEC mycobacteria growth indicator tube (MGIT 960) automated system for drug susceptibility testing of Mycobacterium tuberculosis, J CLIN MICR, 39(12), 2001, pp. 4440-4444
Citations number
33
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Clinical Immunolgy & Infectious Disease",Microbiology
Journal title
JOURNAL OF CLINICAL MICROBIOLOGY
ISSN journal
0095-1137 → ACNP
Volume
39
Issue
12
Year of publication
2001
Pages
4440 - 4444
Database
ISI
SICI code
0095-1137(200112)39:12<4440:EOBMGI>2.0.ZU;2-H
Abstract
The reliability of the BACTEC MGIT 960 system, an automated version of the Mycobacteria Growth Indicator Tube (MGIT), for antimicrobial susceptibility testing of Mycobacterium tuberculosis was evaluated on 78 clinical isolate s. Rifampin (RMP), isoniazid (INH), streptomycin (SM), and ethambutol (EMB) were tested at the following concentrations: 1.0 mug/ml for RMP, 0.1 and 0 .4 mug/ml for INH, 1.0 and 4.0 mug/ml for SM, and 5.0 and 7.5 mug/ml for EM B. Results were compared with those obtained by the BACTEC 460 TB radiometr ic system. Initially the reproducibility study showed 99.5% agreement on re peat testing with all the four drugs. With susceptibility testing of clinic al isolates, excellent agreement between the two systems was found for all the drugs. A total of nine major errors were observed for only three isolat es, resistant according to BACTEC MGIT 960 and susceptible according to BAC TEC 460 TB, to SM (4.0 mug/ml), INH (0.1 mug/ml), and EMB (5.0 mug/ml) (one isolate) and to SM (1.0 mug/ml), INH (0.4 mug/ml), and EMB (5.0 mug/ml) (t wo isolates). When these isolates were tested by using the conventional pro portion method on Lowenstein-Jensen medium, agreement with BACTEC MGIT 960 was found for five results and with BACTEC 460 TB for the remainder. The ti me to report results was 7.9 days by MGIT 960 and 7.3 days by BACTEC 460 TB , which was not found statistically significant (P > 0.05). In conclusion, the performance of BACTEC MGIT 960 was found similar to that of BACTEC 460 TB and this new system can be considered a good alternative to the radiomet ric method for routine susceptibility testing of M. tuberculosis.