Comparison of two automated systems for the isolation of mycobacteria from clinical specimens.

The Bactec MGIT 960 (Becton-Dickinson, UK) automated mycobacterial liquid culture system was compared with the Bactec 9000 MB (Becton-Dickinson) in order to assess ease of use, diagnostic reliability and safety features. One thousand twenty-nine clinical specimens were cultured in parallel, yielding a total of 125 (12.1%) mycobacterial isolates, including 71 Mycobacterium tuberculosis and 18 Mycobacterium avium. The Bactec MGIT 960 demonstrated a mycobacterial recovery rate and speed of detection equivalent to that of the Bactec 9000 MB for clinically important isolates. The Bactec MGIT 960 integrates smoothly into laboratory workflow, does not require needle inoculation and has a much larger capacity than the Bactec 9000 MB.