#BACTEC BLOOD CULTURE BOTTLES SKIN#

Because of the lack of published data regarding the optimal length of incubation for this system, we instituted a 7-day protocol of incubation and, at the end of 1 year, reviewed the times to detection for the organisms recovered to determine the incubation periods necessary to recover clinically significant bacteria and yeasts. The continuously monitored system used in our laboratory is the BACTEC 9240. Evaluations of the ESP and BacT/Alert systems also support a 5-day protocol ( 1, 3, 10, 12). Studies with the BACTEC NR660 and NR860 systems (Becton Dickinson), two of the earlier noncontinuously monitored automated blood culture systems, demonstrated that incubation for 5 days is sufficient to identify the vast majority of bloodstream infections ( 6, 8, 11), and data from one study suggested that 4 days may be sufficient ( 2). Moreover, additional instruments may be required to accommodate the increased number of bottles.

#BACTEC BLOOD CULTURE BOTTLES SKIN#

With such highly automated systems, very little additional labor is required to incubate cultures for a full 7 days however, with longer incubation, more organisms considered to be skin contaminants may be isolated and final results of negative cultures will be delayed. All systems can be programmed by the user to incubate specimens for various time periods recommendations range from 5 to 7 days ( 4, 7, 9). The ESP detects pressure changes in the headspace of the vial, the BacT/Alert detects color changes with a sensor on the bottom of the vial, and the BACTEC 9240 system detects fluorescence.

The primary difference lies in the method used to detect growth. There does not appear to be any major difference in the performances of the systems, and all have been shown to be highly reliable ( 7, 9). There are currently three systems available: ESP (Trek Diagnostic Systems, Westlake, Ohio), BacT/Alert (Organon Teknika Corp., Durham, N.C.), and BACTEC 9240 (Becton Dickinson, Cockeysville, Md.). The most technologically advanced systems for culturing blood are the continuously monitored blood culture instruments.

Culturing blood specimens for microorganisms is one of the most important functions of the microbiology laboratory.

Bactec blood culture bottles