Background and methods: From 1996 through 2006, 195 cases were reported as transfusion-related acute lung injury (TRALI) to the Serious Hazards of Transfusion scheme and from 1999 onward classified by probability, using clinical features and HLA and/or HNA typing. From late 2003, the National Blood Service provided 80 to 90 percent of fresh-frozen plasma (FFP) and plasma for platelet (PLT) pools from male donors.
Results: Forty-nine percent of reports were highly likely/probable TRALI, and 51 percent possible/unlikely. Of 96 investigations, donor antibodies recognizing recipient antigens were found in 73 cases (65%), with HLA Class I in 25 of those (40%), HLA Class II antibodies in 38 (62%), and granulocyte antibodies in 12 (17%). A review in 2003 revealed that the TRALI risk/component was 6.9 times higher for FFP and 8.2 times higher for PLTs than for red blood cells, and that in donors of implicated FFP/PLTs, white blood cell antibodies were found 3.6 times more often than by chance (p <or= 0.0001), with all implicated donors being female. Provision of male plasma was associated with a reduction in TRALI reports from 36 in 2003 to 23 in each of 2004 and 2005 and 10 in 2006. Highly likely/probable cases reduced from 22 in 2003 to 13, 6, and 3 [corrected] in the 3 subsequent years, with cases implicating FFP or PLTs with positive donor serology [corrected] falling from 16 to 9, 3, and 1 respectively.
Conclusions: The risk of highly likely/probable TRALI due to FFP has fallen from 15.5 per million units issued during 1999 through 2004 to 3.2 per million during 2005 through 2006 (p = 0.0079) and from 14.0 per million to 5.8 per million for PLTs.