Comparison of the Septi-Chek AFB and BACTEC systems and conventional culture for recovery of mycobacteria.
The performance of the Septi-Chek AFB system was compared with that of the BACTEC radiometric system and that of Lowenstein-Jensen agar slants (LJ) for detection of mycobacteria in clinical specimens. A total of 642 specimens were cultured; 61 (9.5%) yielded mycobacteria. Mycobacterium tuberculosis (34 isolates) and Mycobacterium avium complex (25 isolates) were the predominant species isolated. Of the 61 culture-positive specimens, 30 were smear positive and 31 were smear negative. Overall, 95% of the positive specimens were detected by Septi-Chek and BACTEC (100% of M. tuberculosis isolates) and 75% by LJ (82% of M. tuberculosis isolates). The mean times to detection were 15 days for BACTEC, 23 days for Septi-Chek, and 27 days for LJ. Of the 30 smear-positive specimens, 100% were recovered by Septi-Chek and BACTEC and 90% were recovered by LJ. Of the 31 smear-negative specimens, 90% were detected by Septi-Chek and BACTEC and 61% were detected by LJ. The Septi-Chek and BACTEC systems are superior to the conventional (LJ) mycobacterial culture method. Although Septi-Chek requires more time for the detection of mycobacteria than BACTEC, it is comparable in terms of overall recovery.
Sewell
D L
DL
Laboratory Service, Veterans Affairs Medical Center, Portland, Oregon.
Rashad
A L
AL
Rourke
W J
WJ
Poor
S L
SL
McCarthy
J A
JA
Pfaller
M A
MA
D001431:Bacteriological Techniques; D006801:Humans; D008297:Male; D015269:Mycobacterium avium Complex / Q000302:isolation & purification*; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D013997:Time Factors