Bacterial contamination of random‐donor platelets in a university hospital in the midwestern region of Brazil

Abstract

BACKGROUND: Bacterial blood contamination was probably the first recognized transfusion-transmitted disease. Although the transfusion-associated bacterial sepsis has been known for a long time, it remains an important health problem. At present it is the most frequently reported cause of infectious transfusion-related fatalities. The aims of the study were to determine the prevalence of microbiologic contamination in random-donor platelets (RDPs) and to identify the isolated microorganism obtained from a Brazilian university hemotherapy service. STUDY DESIGN AND METHODS: A total of 2000 RDPs were analyzed from November 2004 to June 2005. The time of storage of the platelet (PLT) concentrates studied ranged from the day of donation (Day 0) to the fifth day of storage (Day 5). The RDP cultures were initially performed in pools with bottles containing brain heart infusion (BHI) growth medium, and cultures were incubated aerobically at 37 degrees C for up to 7 days and subcultured onto chocolate agar at 37 degrees C for 48 hours under conditions of microaerophilia. In the cases of positivity of one pool, the culture was individually performed for all the samples of that pool. RESULTS: Eight units (0.4%; 95% confidence interval, 0.31-0.49) were found to be contaminated. Isolated microorganisms were three Acinetobacter lwoffii, one Enterobacter intermedium, one Serratia phymuthica, one Staphylococcus haemolyticus, one Staphylococcus hominis, and one Bacillus sp. CONCLUSION: PLT concentrates were contaminated with bacteria in 0.4 percent of tested units, which represents a potential risk to patients and a public health problem. Regarding the contaminant microorganisms, a predominance of Gram-negative agents was observed (62.5%).