[Anti-A antibodies and bacterial contamination of platelet concentrates].

Objectives: The possible ABO group antibodies protective function against several infections has been classically described. We analyze the platelet concentrates (PC) bacterial control results and their ABO antibodies.

Material and methods: We studied 245 outdated PCs (> 5 days). The samples were sterilely collected for adequate microbiological investigation studies on sheep-blood agar plates. If bacterial growth is found, the microbiological identification is performed on the basis of standard tests, the specific anti-biotype being achieved by disk-diffusion method on Müeller-Hinton agar plates, and the red cell concentrate was analyzed.

Results: Bacterial growth by negative coagulase Staphylococcus was found in 10 PCs (4.1%; CI95%; 1.97-7.37). The contaminated PCs lacked natural anti-A antibodies. There were no statistical differences when we analyzed the PC's age, colour or blood group.

Comments: The anti-A antibodies may be a protective factor versus PCs contamination caused by resident bacteria.