Escherichia coli sepsis from contaminated platelet transfusion.

Transfusion of pooled platelet concentrate (PC) caused a septic reaction characterized by sustained hypotension, high cardiac output, and low systemic vascular resistance. Investigation demonstrated the same strain of Escherichia coli in the patient's blood, the transfused pooled PC, and recalled packed red blood cells separated from the same unit of whole blood as one of the platelet units in the contaminated pool. Five hundred other units of PC from the same supplier were cultured prospectively, and 7% were bacterially contaminated. The level of contamination was 20 or fewer colony-forming units per milliliter in all except one unit, the only one associated with a febrile transfusion reaction. This episode illustrates the continuing importance of sepsis as a cause of platelet transfusion reactions and demonstrates the usefulness of appropriate cultures and epidemiologic information in assessing the source.