1996 年 42 巻 6 号 p. 294-298
Bacterial contamination was observed in a platelet concentrate obtained by apheresis using COBE SPECTRA and stored for 45 hours with agitation at 20 to 24°C. The platelet product was contaminated with 107 CFU/ml of Bacillus cereus. The contamination was likely attributable to bacteria on the skin at the phlebotomy site, because 1) apheresis was performed in a closed system and 2) Bacillus cereus are known to exist ubiquitously including the skin surface, and to be resistant to the chlorohexidine-ethanol that is routinely used for disinfection of phlebotomy site in our blood center. In a spike experiment with apheresis platelets, the growth of Bacillus cereus was vey rapid, with a doubling time of 6 hours to reach 107 CFU/ml in 2 days.
Leukocyte depletion resulted in reduced phagocytic activity and allowed rapid growth of the contaminating bacteria in platelet products. There findings enpharize the importance of preventing as far as possible. In addition, platelet recipients, largely comprising leukemia patients, are vulnerable to infection.