Bacterial sepsis secondary to platelet transfusion: an adverse effect of extended storage at room temperature.

In a 3-month period four episodes of bacterial sepsis related to contaminated random donor platelet concentrates were observed. Evaluation incriminated extended (5 or more days) platelet storage. To determine if platelets stored for longer periods were likely to have greater bacterial contamination, platelet concentrates were inoculated with bacteria and daily quantitative bacteriology was performed. In vitro studies using polyolefin bags indicated contamination could occur with a single organism of Staphylococcus epidermidis. By 72 hours, platelet concentrates contained from 10(3) to 10(8) organisms per 0.1 ml depending on the inoculum size. By 6 days all inoculated units contained 10(7) to 10(9) organisms per 0.1 ml.