Effect of leukocyte romoval filter on platelet function and prevention of post-transfusion side reactions.

A leukocyte removal filter (Pall PL Filter) were widely believed to show no significant effect on platelet function and platelet count of platelet concentrates. In this paper, we evaluated platelet function of platelet concentrates in detail. In the first 6ml filtered samples, ADP, collagen and epinephrine-induced aggregations were depressed and platelet count showed significant decrease with platelet recovery rate of 72%. These abnormalities returned to normal in more than 18ml filtered samples. In pooled samples, no significant changes were observed in platelet function before and after filtration. In twelve patients with hematological disorders, post-transfusion side reactions were significantly low incidence in those with the filter (25%) compared with those without filter (75%). Our results demonstrated that leukocyte removal filter was effective for the prevention of post transfusion side reactions but could give some possibility that very small amount of platelet transfusion might not be useful for preventing the bleeding.