Swiss Haemovigilance Data and Implementation of Measures for the Prevention of Transfusion Associated Acute Lung Injury (TRALI).

SUMMARY: In Switzerland, blood donations are collected exclusively from healthy non-remunerated voluntary blood donors mainly by 13 regional Blood Transfusion Services throughout the country. Thereby, self-sufficient blood supply for a population of about 7.5 million is achieved, and approximately 300,000 units of red cells, 75,000 therapeutic units of fresh plasma, and 20,000 therapeutic units of platelets are transfused annually. Reporting to Swissmedic (the Swiss agency for therapeutic products) of all suspected adverse transfusion events on a standardised form is mandatory. Data are then analysed to estimate the risks of the most serious transfusion events. Together with transfusion of an incorrect blood component and bacterial contamination of platelet concentrates, TRALI is a significant risk of transfusion in Switzerland and occurs in approximately every 8,000-20,000 FFP transfusions according to current haemovigilance data. Among 25 reported cases between 2002 and November 2007, 4 are proven immune TRALI, 2 are highly likely immune TRALI, 10 are possibly immune TRALI, 8 are non-immune TRALI, and 1 is a suspected case which could not be confirmed as TRALI. Based on the hypothesis of an immunological trigger of TRALI, an exclusion of the transfusion of plasma from female donors can be considered as a precautionary measure which might have prevented 4 cases of proven immune TRALI, 2 cases of highly likely immune TRALI, and an unknown number of the 10 cases of possibly immune TRALI. Based on these data and encouraging preliminary reports of the effects of comparable measures in other countries, the decision was made that starting with January 1st 2007 the production of quarantined FFP is restricted to donations from men or from women confirming that they have never been pregnant (to their knowledge) or with negative tests for antibodies against HLA class I and II. The analysis of further vigilance data is needed to elucidate the efficacy of this preventive measure.