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Updated: Nov 1, 2025
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Published on: October 15, 2014
Platelet Component False Positive Detection Rate in Aerobic and Anaerobic Primary Culture: A Systematic Review and
Jessica Corean1, Sandra K White1, Robert L Schmidt2
1Department of Pathology, University of Utah, Salt Lake City, UT, USA.
Abstract:
Septic reactions from platelet transfusions are one of the leading causes of transfusion-associated mortality. The FDA guidance for platelet bacterial risk control includes bacterial culture using both aerobic and anaerobic bottles. Several studies have reported false positive rates (FPR) of culture, but these data have not been summarized or influencing factors analyzed. A systematic review and meta-analysis was performed according to published guidelines to assess the false positive rate and influencing factors. Eighteen studies were included for analysis. The combined aerobic/anaerobic FPR was 2.4 events per thousand (EPT) with a prediction interval of 0.5 to 5.7, while the aerobic FPR rate was 1.0 EPT (prediction interval: 0.2-2.2) and the anaerobic rate was 1.8 EPT. Estimates were based on a total of almost 5 million units tested. The rate of false positives due to instrument error was between 0.5-1.7 EPT, while it was between 0.3-1.0 EPT for sampling contamination based on whether only aerobic, anaerobic, or aerobic/anaerobic cultures were performed. The FPR is approximately 2 to 5 times higher than the literature reported true positive rate of 0.5 EPT.
Insights
False positive rates in platelet transfusion bacterial cultures are high, potentially misleading safety efforts. This systematic review analyzes culture methods to improve accuracy and patient safety.
Area of Science:
- Hematology
- Microbiology
- Public Health
Background:
- Septic reactions from platelet transfusions are a significant cause of transfusion-associated mortality.
- Current FDA guidelines mandate aerobic and anaerobic bacterial cultures for platelet safety.
- Previous studies reported false positive rates (FPR) but lacked comprehensive summarization and analysis of influencing factors.
Purpose of the Study:
- To systematically review and meta-analyze existing data on the false positive rate (FPR) of bacterial cultures in platelet transfusions.
- To identify and analyze factors influencing the FPR in platelet bacterial risk control.
Main Methods:
- A systematic review and meta-analysis were conducted following established guidelines.
- Eighteen studies, encompassing nearly 5 million tested units, were included in the analysis.
- FPR was assessed for combined aerobic/anaerobic, aerobic-only, and anaerobic-only culture methods.
Main Results:
- The combined aerobic/anaerobic FPR was 2.4 events per thousand (EPT) (prediction interval: 0.5-5.7).
- Aerobic-only cultures showed an FPR of 1.0 EPT (0.2-2.2), while anaerobic-only cultures had an FPR of 1.8 EPT.
- Instrument error contributed 0.5-1.7 EPT false positives, and sampling contamination contributed 0.3-1.0 EPT.
Conclusions:
- The overall FPR of platelet bacterial cultures is significantly higher than the true positive rate, potentially impacting transfusion safety protocols.
- Understanding the sources of false positives, such as instrument error and contamination, is crucial for refining bacterial detection methods.
- The findings highlight the need for improved strategies to reduce false positives and enhance the reliability of bacterial screening in platelet products.
