Are facilities routinely performing platelet sterility QC with the BacT/ALERT® system using both aerobic and anaerobic culture bottles?

A Blood Bank Compliance Officer for a hospital network in Southern California reports that during a recent inspection of their blood donation program by the State of California, the inspector raised a question about the wording of the March 2006 version of the package insert for BacT/ALERT® which reportedly "Strongly recommends" that platelet sterility QC testing include both aerobic and anaerobic culture bottles. The Compliance Officer acknowledges that her network is currently only testing donated platelets for contamination using an aerobic culture with the BacT/ALERT® system. She comments that she heard strong support for using only an aerobic culture for platelet sterility QC at the 2006 AABB meeting in Miami. She asks if other facilities are routinely performing platelet sterility QC by the BacT/Alert system both aerobic and anaerobic culture bottles. Finally, she wonders if anyone is aware of the data that prompted the strong recommendation to be printed in the package insert?

The following comments have been received.

1. According to Dr. Mark Brecher of the University of North Carolina at Chapel Hill School of Medicine, the BioMérieux (formerly Organon Teknica) package inserts have, since initially cleared for platelet quality control stated "For best overall recovery when culturing platelet specimens, it is strongly recommended that more that one type of culture bottle be utilized (e.g. one aerobic and one anaerobic)".
   
   The inclusion of this recommendation resulted from the data submitted to the FDA for approval which included data from both bottles and a review of the literature. The inclusion of the anaerobic bottle was based on:
   1. The observation that obligate anaerobic organisms (e.g. Clostridium perfringens) known to have been implicated in cases of post transfusion sepsis frequently could only be isolated with the anaerobic bottles.
   2. This initial data set and subsequent submissions showed that for many “aerobic” organisms recovery was faster in the anaerobic bottles.
   3. The known fact that with low initial concentrations, the maximum volume cultured optimizes the chance of a successful recovery.

Dr. Brecher adds that most recently, his lab has shown with one organism (S. lugdenensis) known tqo have caused a fatal transfusion reaction, recovery was faster in the anaerobic bottle when concentrations were low, but was equivalent at higher concentrations. Thus "for best overall recovery", the phrase is used in the broad sense of both time to recovery and type of organisms recovered.

In terms of current usage, a survey in 2004 by the AABB showed that of those blood centers employing the BacT/ALERT®, 85 percent used only an aerobic bottle, whereas 46 percent of hospital blood banks employed both an aerobic and an anaerobic bottle. See: Silva MA, Gregory KR, Carr-Greer MA, Holmberg JA, Kuehnert MJ, Brecher ME; Summary of the AABB Interorganizational Task Force on Bacterial Contamination of Platelets: Fall 2004 impact survey. Transfusion. 2006;46:636-41.

Although there were some presentations at the recent AABB meeting in support of using an aerobic only bottle, other presentations argued for the use of the anaerobic bottle. A PDF of the presentation that Dr. Brecher made may be found HERE. In this presentation he argued that anaerobic bottles were indicated for the following reasons:

1. The Package inserts recommends two bottles.
2. Anaerobic organisms can kill.
3. The greater the volume, the greater the sensitivity.
4. Some aerobic organisms "prefer" one media over another.
5. 7 days storage requires anaerobic culture.

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