Antierythrocyte antibodies in hemodialysis and kidney transplant patients

Anti‐N‐Like and Anti‐Form Red Cell Antibodies in Chronic Hemodialysis Patients

Allogeneic red blood cell (RBC) transfusions and the use of reusable dialyzers sterilized with formaldehyde can lead to RBC alloimmunization in chronic hemodialysis patients. The formed RBC alloantibodies have been implicated in immediate kidney allograft failure and decreased RBC survival observed in these patients. Using indirect antiglobulin test, direct antiglobulin test (DAT), and direct Polibrene test (DPT), we detected an RBC alloimmunization rate of 17.2% (11/64) in transfused hemodialysis patients, and found the presence of anti-N-like and anti-Form antibodies in 5 (5.7%) and 53 (60.9%) individuals, respectively. The sensitivity rate of the DPT was significantly higher than that of the DAT in detecting anti-Form, but the DAT showed a higher specificity rate compared with the DPT. We conclude that patients treated with reusable dialyzers sterilized with formaldehyde may develop specific RBC alloantibodies that could increase the potential risk of hemolysis, decrease survival of RBCs, and increase the need of blood supply.

Additional red blood cell alloantibodies after blood transfusions in a nonhematologic alloimmunized patient cohort: is it time to take precautionary measures?

BACKGROUND

Red blood cell (RBC) alloimmunization is common in transfused patients. Most studies report on the rate of alloimmunization in chronically transfused patients, which can be as high as 60 percent. Less is known on the incidence of clinically relevant antibodies in accidentally transfused patients. Because the probability of repeat transfusion increases with longer life expectancy, it was wondered to which extend non-chronically transfused alloimmunized patients are prone to form additional antibodies after repeat transfusion events.

STUDY DESIGN AND METHODS

A 20-year retrospective multicenter study was performed analyzing additional alloantibody formation, against the RH, KEL, FY, JK, and MNS blood group systems.

RESULTS

After additional transfusions, 21.4 percent of 653 patients produced additional antibodies, resulting in 157 new antibody specificities. At the end of the study 33.4 percent of patients had multiple antibodies. Eighty of 140 patients (57%) who formed additional antibodies did so after one transfusion episode of a median of 2 units of RBCs. Based on the antigen profile of 316 patients, 83 percent of antibodies could have been prevented by extended matching for the C, E, c, K, Fy(a), and Jk(a) antigens. Considering the current available donors in our region, 1 to 10 percent of potential donors would be available for 39 percent of patients and greater than 10 percent of potential donors for 61 percent of patients.

CONCLUSION

It has been shown that nonhematooncologic alloimmunized patients are high antibody responders, with a more than 20 times increased risk to form antibodies compared to first-time alloimmunization risk. If extended matching for C, c, E, K, Fy(a), and Jk(a) antigens in the future is considered, this group should be taken into account.