A Japanese multi-institutional collaborative study of antigen-positive red blood cell (RBC) transfusions in patients with corresponding RBC antibodies.

BACKGROUND AND OBJECTIVES: It is sometimes difficult to obtain antigen-negative red blood cells (RBCs) for patients with antibodies against RBCs. However, the frequency and severity of the adverse reactions have not been well elucidated. Here, we conducted a multi-institutional collaborative study to clarify the background, frequency and clinical significance of antigen-positive RBC transfusions to patients with the respective antibodies. MATERIALS AND METHODS: The survey included the background of patients, antigens on RBCs transfused, total amount of antigen-positive RBCs transfused, results from antibody screen and direct antiglobulin tests, specificity of antibodies, adverse reactions and efficacies. All antibodies were surveyed regardless of their clinical significance. RESULTS: In all, 826 cases containing 878 antibodies were registered from 45 institutions. The main reasons for antigen-positive RBC transfusions included 'negative by indirect antiglobulin test' (39%) and 'detection of warm autoantibodies' (25%). In 23 cases (3% of total), some adverse reactions were observed after antigen-positive RBC transfusion, and 25 antibodies (9 of 119 clinically significant and 16 of 646 insignificant antibodies) were detected. Non-specific warm autoantibodies were detected in 9 cases, anti-E in 5 cases, 2 cases each of anti-Lea , anti-Jra or cold alloantibodies, and 1 case each of anti-Dib , anti-Leb or anti-P1. Other antibodies were detected in 2 further cases. Five (22%) of these 23 cases, who had anti-E (3 cases) or anti-Jra (2 cases), experienced clinically apparent haemolysis. CONCLUSIONS: Adverse reactions, especially haemolysis, were more frequently observed in cases with clinically significant antibodies than those with clinically insignificant antibodies (P < 0·001).

Accumulated cytokines in stored autologous blood do not cause febrile nonhemolytic transfusion reactions.

Accumulated inflammatory cytokines are considered to be a cause of febrile nonhemolytic transfusion reactions (FNHTRs) of platelet transfusions. Inflammatory cytokines have been found in red cell components stored at 4 degrees C; however, their relationship to FNHTRs has not been clearly demonstrated following red cell transfusions. We measured cytokine levels in stored blood, and determined whether inflammatory marker concentrations were elevated in subjects infused with autologous blood stored for 5 weeks. In conclusion, cytokines accumulated in blood stored at 4 degrees C, but their increases were small. No changes were seen in recipients' inflammatory markers after blood transfusion. Our results indicate that cytokines in stored autologous blood are not responsible for FNHTRs.

Pre-transfusion screening for platelet-reactive antibodies.

We retrospectively compared the cost of platelet concentrates (PCs) used for patients whose serum had already been screened for platelet-reactive antibodies with the cost for patients whose serum was examined after the commencement of treatment using platelets. On the basis of 774 patients' data, the mean cost of PCs for the latter group of patients ($5562) was higher than that for the former group ($2547). Screening beforehand ensured a prompt supply of specific PCs, and costs were suppressed by the avoidance of multiple transfusions. We conclude that screening for platelet-reactive antibodies followed by administration of crossmatch-negative PCs appears to be both clinically and economically advantageous.

Transfusion-related problems following major ABO-incompatible bone marrow transplantation.

A case of acute myelocytic leukemia has been reported in which the patient's surviving original B lymphocytes after pretransplant-conditioning chemotherapy probably reproduced hemagglutinins that reacted with red blood cells (RBCs) derived from engrafted donor marrow for a prolonged period of time. Although the direct antiglobulin test was negative and hemagglutinins were not detectable in the patient's sera but only in the eluate, the antibodies reappeared in the sera. Therefore, it is important to confirm that the eluate does not contain antibodies that would react with donor-derived RBCs when the type of red cell used for transfusion is switched from the patient's type to the donor's type in a major ABO-mismatched bone marrow transplantation (BMT). Testing of ABO subgroups using lectins is also recommended to avoid a delayed hemolytic transfusion reaction following BMT.