REASSESSMENT OF THE INCUBATION-TIME IN A CONTROLLED CLINICAL COMPARISON OF THE BACT ALERT AEROBIC FAN BOTTLE AND STANDARD ANAEROBIC BOTTLE USED AEROBICALLY FOR THE DETECTION OF BLOOD-STREAM INFECTIONS/

This study assessed the minimum incubation time required to detect blo odstream infections during a controlled clinical comparison of the per formance characteristics of rite Bact/Alert aerobic FAN bottle and the standard anaerobic bottle used aerobically except on a selective basi s. Blood was collected from adults with suspected bloodstream infectio ns and inoculated into each bottle, which was monitored in the BacT/Al ert Microbial Detection System. The anaerobic bottle was vented before incubation except when cultures were obtained from patients on the co lorectal and gynecologic surgical and emergency services. Statistical analysis was limited to those culture sets in which each bottle was in oculated with greater than or equal to 8 int of blood and bacterial gr owth was considered to be clinically significant. A total of 682 posit ive cultures from 243 patients satisfied the inclusion criteria. Signi ficantly more isolates of Staphylococcus aureus (p <0.001), S. epiderm idis (p <0.001), other congulase-negative staphylococci (p <0.001), En terococcus spp. (p = 0.04), Escherichia coli (p = 0.03), all Enterobac teriaceae (p <0.001), Pseudomonas aeruginosa (p = 0.001), and Candida spp. (p <0.001) were detected by the aerobic FAN bottle. Significantly more septic episodes due to S. aureus, S. epidermidis. other coagulas e negative staphylococci, Enterobacteriaceae, P. aeruginosa, and Candi da spp. were detected by the aerobic FAN bottle. Significantly more ba cterial isolates were detected by the aerobic FAN whether or not antib iotics were being administered at the time of blood culture, whereas t here were significantly fewer positive cultures in the vented standard anaerobic bottle when patients were receiving antimicrobial therapy t han when they were not. All but 5% of positive cultures were detected within three days. Only six of the cultures requiring four or five day s of incubation represented true misses, and only one of these six res ulted in a change in therapy which, however, did not affect the patien t's outcome. (C) 1998 Elsevier Science Inc.