Comparative recoveries of Mycobacterium avium-M. intracellulare from isolator lysis-centrifugation and BACTEC 13A blood culture systems.

Blood cultures processed with a lysis-centrifugation (Isolator) system and a radiometric (BACTEC 13A) broth system were compared for the recovery of Mycobacterium avium-M. intracellulare from patients with acquired immunodeficiency syndrome. Forty-nine isolates of M. avium-M. intracellulare were recovered by both systems, 9 were recovered by the Isolator system only, and 12 were recovered by the BACTEC system only. Average times to detection were 16 and 14 days for the Isolator and BACTEC systems, respectively. There was no significant difference between the two blood culture systems in sensitivity or time to detection.