Determinants of transfusion-associated bacterial contamination: results ofthe French BACTHEM Case-Control Study

BACKGROUND: Transfusion-associated bacterial contamination (TABC), probably the most frequent transfusion-transmitted infection, may induce serious ad verse events. Systematic information and documentation on determinants are lacking. STUDY DESIGN AND METHODS: The BACTHEM Study is a French matched case-contro l study assessing TABC determinants. Included were cases of TABC reported i n France in a 2-year period, as determined from uniform definitions. Inform ation on recipient; blood component; and donor-related potential determinan ts was collected on site. ORs were estimated by conditional logistic regres sion. RESULTS: Of the 158 cases of suspected TABC reported, 41 that involved tran sfusion with 25 RBCs and 16 platelet concentrates were included. Gram-negat ive rods accounted for nearly half of the bacteria species involved and for all six deaths. In comparison with the risk of TABC for patients receiving RBCs for anemia, the risk was higher for patients receiving RBCs for pancy topenia (OR, 7.3; 95% CI, 1.3-41.0) and for those receiving platelets for t hrombocytopenia (OR, 5.3; 95% CI, 1.2-24.1). Other potential determinants w ere platelet transfusion for pancytopenia (OR, 4.5; 95% CI, 0.5-40.0), immu nosuppressive treatment (OR, 2.8; 95% CI, 0.7-10.6), shelf-life of more tha n 1 day for platelets or 8 days for RBCs (OR, 2.6; 95% CI, 0.7-9.6), and mo re than 20 previous donations by donors (OR, 1.9, 95% CI, 0.7-5.3). CONCLUSION: This first comparative study revealed TABC determinants that su ggest approaches for prevention.