[Rapid diagnosis of mycobacteria, especially Mycobacterium tuberculosis and Mycobacterium avium complex, using MB Check system].
Fourty-five sputum specimens were subjected to isolation for mycobacteria either MB Check system (MB method; F. Hoffmann-La Roche Ltd., Basel, Switzerland) or 3% Ogawa egg medium (Ogawa method). Test sputum was treated with 4 volumes of 4% NaOH for 1-2 min and 0.1 ml of the resulting mixture was inoculated onto 3% Ogawa egg medium. The remaining portion of the mixture was neutralized with IN HCl, diluted with 1/15 M phosphate buffer (PB; pH 6.8), and subsequently centrifuged at 3,000 rpm for 20 min. The sediment was suspended in 1.5 ml of PB and 0.5 ml each was inoculated into MB Check M bottle (20 ml) supplemented with M supplement (1 ml). In MB method, bacterial growth was measured on Middlebrook 7H11 agar medium and Middlebrook 7H11 agar medium containing NAP (p-nitro-alpha-acetylamino-beta-hydroxy-propiophenone). Among 45 sputum specimens, the number of positive specimens for mycobacterial growth in the above two cultivation methods and time required for growth were as follows: 3% Ogawa egg medium; 12 specimens (26.7%) gave positive growth, including 7 of M. tuberculosis complex strains on 14-35 days (average 22 days) and 5 of M. avium complex strains on 14-21 days (average 18 days); MB method; 15 of specimens (33.3%) gave positive growth, including 8 of M. tuberculosis complex strains on 7-21 days (average 15 days), 6 of M. avium complex strains on 7-14 days (average 11 days) and 1 of M. scrofulaceum strain on 28 days. There was no specimen which was positive for mycobacterial growth on 3% Ogawa egg medium but negative on MB medium.
Saito
H
H
Department of Microbiology and Immunology, Shimane Medical University, Izumo, Japan.
Tomioka
H
H
Sato
K
K
Inoue
K
K
Shigeto
E
E
D003470:Culture Media; D006801:Humans; D015269:Mycobacterium avium Complex / Q000302:isolation & purification; D015270:Mycobacterium avium-intracellulare Infection / Q000175:diagnosis* / Q000382:microbiology; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification; D011933:Reagent Kits, Diagnostic; D013183:Sputum / Q000382:microbiology; D014376:Tuberculosis / Q000175:diagnosis* / Q000382:microbiology
D003470:Culture Media; D011933:Reagent Kits, Diagnostic