Bacterial contamination of platelet components not detected by BacT/ALERT

• Published in: Transfusion medicine (Oxford, England) Vol. 28; no. 1; pp. 65 - 70
• Main Authors: Abela, M. A., Fenning, S., Maguire, K. A., Morris, K. G.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.02.2018
• Subjects: automated bacterial culture detection; platelet components; visual inspection; platelet components; visual inspection; automated bacterial culture detection
• ISSN: 0958-7578; 1365-3148
• DOI: 10.1111/tme.12458

SUMMARY Objectives To investigate the possible causes for false negative results in BacT/ALERT® 3D Signature System despite bacterial contamination of platelet units. Background The Northern Ireland Blood Transfusion Service (NIBTS) routinely extends platelet component shelf life to 7 days. Components are sampled and screened for bacterial contamination using an automated microbial detection system, the BacT/ALERT® 3D Signature System. We report on three platelet components with confirmed bacterial contamination, which represent false negative BacT/ALERT® results and near‐miss serious adverse events. Methods NIBTS protocols for risk reduction of bacterial contamination of platelet components are described. The methodology for bacterial detection using BacT/ALERT® is outlined. Laboratory tests, relevant patient details and relevant follow‐up information are analysed. Results In all three cases, Staphylococcus aureus was isolated from the platelet residue and confirmed on terminal sub‐culture using BacT/ALERT®. In two cases, S. aureus with similar genetic makeup was isolated from the donors. Conclusion Risk reduction measures for bacterial contamination of platelet components are not always effective. Automated bacterial culture detection does not eliminate the risk of bacterial contamination. Visual inspection of platelet components prior to release, issue and administration remains an important last line of defence.