Platelet transfusions carry risk of infection

Despite the fact that a blood infection called bacterial sepsis is one of the most frequent causes of death in people who have received platelet transfusions, most infectious-disease specialists are not aware of recent standards requiring bacterial testing for contamination of platelets, according to a new report.

Unlike other blood components that are stored in the cold, platelets are particularly vulnerable to bacterial growth because they are stored at room temperature.

Writing in the US Centers for Disease Control and Prevention's Morbidity and Mortality Weekly Report (MMWR), Dr. A. Arendt, with the Cuyahoga County Board of Health in Ohio, and associates describe two case reports of patients who died after receiving pooled platelets contaminated with the bacteria Staphylococcus aureus and S. lugdunensis.

They also report results of surveys sent out by the Infectious Diseases Society of America to infectious-disease consultants in the US. Among the 399 respondents, 36% reported they were unaware that "bacterial contamination of platelets is one of the most common infectious risks of transfusion therapy."

Only 20% were familiar with the 2004 standard set by the AABB (formerly the American Association of Blood Banks) for bacterial testing of all platelet components.

Even when testing is performed, false-negative results are possible, so doctors should consider the possibility of bacterial contamination when they are treating patients who develop fevers in reaction to transfusions, the MMWR's editors pointed out in a note published with the report.

SOURCE: Morbidity and Mortality Weekly Report CDC Surveillance Summary, February 25, 2005.