During 2018–2021, eight septic transfusion reactions occurred from transfusion of platelet units contaminated with Acinetobacter spp., Staphylococcus saprophyticus, Leclercia adecarboxylata, or a combination of those environmental organisms. Whether biofilm formation contributed to evasion of bacterial risk mitigations, including bacterial culture, point-of-care testing, or pathogen-reduction technology, is unclear. We designed a 12-well plate-based method to evaluate environmental determinants of single-species and multispecies biofilm formation in platelets. We evaluated bacteria isolated from septic transfusion reactions for biofilm formation by using crystal violet staining and enumeration of adherent bacteria. Most combinations of bacteria had enhanced biofilm production compared with single bacteria. Combinations involving L. adecarboxylata had increased crystal violet biofilm production and adherent bacteria. This study demonstrates that transfusion-relevant bacteria can produce biofilms well together. More work is needed to clarify the effect of biofilms on platelet bacterial risk control strategies, but US Food and Drug Administration–recommended strategies remain acceptable.

2018 年至 2021 年期间，因输注被不动杆菌属、腐生葡萄球菌、脱羧Leclercia adecarboxylata或这些环境微生物的组合污染的血小板单位，发生了 8 起败血症性输血反应。生物膜的形成是否有助于逃避细菌风险缓解措施，包括细菌培养、即时检测或病原体减少技术，尚不清楚。我们设计了一种基于 12 孔板的方法来评估血小板中单物种和多物种生物膜形成的环境决定因素。我们通过使用结晶紫染色和粘附细菌计数来评估从脓毒症输血反应中分离的细菌的生物膜形成。与单一细菌相比，大多数细菌组合都增强了生物膜的产生。涉及脱羧乳杆菌的组合增加了结晶紫生物膜的产生和粘附细菌。这项研究表明，与输血相关的细菌可以很好地一起产生生物膜。需要做更多的工作来阐明生物膜对血小板细菌风险控制策略的影响，但美国食品和药物管理局推荐的策略仍然可以接受。