Evaluation of the Automated Immunohematology Analyzer DAYMATE M

BACKGROUND: An automated immunohematology analyzer, DAYMATE M (DAY Medical, Switzerland), has been recently developed. The potential of this analyzer to improve test results has been evaluated. METHODS: A total of 300 blood samples from Seoul St. Mary's hospital and Incheon St. Mary's hospital were tested for ABO and RhD typing. In addition, 336 antibody screening test (AST) samples and 82 patients treated with hematopoietic stem cell transplantation (HSCT) were included. AST results by DAYMATE M were compared with those obtained by a manual method using DS-Screening II (Bio-Rad Laboratories, Switzerland) and red blood cells from Selectogen (Ortho-Clinical diagnostics Inc., USA). RESULTS: Of the 300 patients enrolled, 87, 73, 79, and 61 had type A, B, O, and AB blood, respectively. The concordance rate was 99.9% for cell typing and 97.0% for serum typing. One discordant case was classified as type B instead of AB, and six discordant serum-typing cases were type A, but classified as type AB. Among the 336 AST samples, the concordance rate was 93.2%. From 136 positive cases, six were discordant. Within the 82 HSCT-treated patients, the concordance rate for ABO blood typing was 92.2%. Among the six discordant cases, DAYMATE M typed four cases as donor type where the standard method typed them as the recipient blood type. CONCLUSIONS: The DAYMATE M automated immunohematology analyzer performs reliably for ABO and RhD typing, as well as for ASTs and on samples from patients treated with HSCT.

Experience of a Performing Alternative Assessment Procedure for Tests without External Proficiency Test Program / 대한수혈학회지

BACKGROUND: Proficiency testing is part of a total quality management program that provides objective evidence of clinical laboratory testing competence for customers, accrediting bodies, and regulatory agencies. Performing alternative assessment procedures for clinical tests, without proficiency testing, is recommended by Clinical and Laboratory Standards Institute (CLSI) guideline. In our study, an alternative assessment procedure was performed for blood bank tests that do not have an external proficiency program. METHODS: The laboratory for development and an evaluation center, supervised the program. Proficiency testing by seven institutions was performed 3 times at 6 month intervals by evaluating isoagglutinin and anti-D titers, and Weak D, Rh C and E typing, using ID-Internal Quality Control (Bio-Rad Laboratories) kits. RESULTS: Isoagglutinin and anti-D titer results were within one fold dilution range for all seven participating institutions, and Weak D, Rh C and E typing results all demonstrated identical antigenic reference patterns. CONCLUSION: An alternative assessment procedure was successfully performed without a proficiency testing program. Commercially manufactured reference materials could be an alternative method to support commutable, external, proficiency testing program.

A Case of Autoimmune Hemolytic Anemia Caused by Anti-D and Anti-C in RhD Positive Patient / 대한수혈학회지

We report a case of autoimmune hemolytic anemia caused by anti-D and anti-C in an RhD positive patient with Epstein-Barr Virus (EBV) infection. The patient achieved complete response by transfusion, treatment with a cytotoxic drug and plasmapheresis. A 66-year-old male patient visited the local hospital for exertional dyspnea. Incompatible crossmatching resulted in the transfer of the patient to our institution for transfusion. Anti-D, C were identified as the autoantibodies causing hemolytic anemia by the use of a direct antiglobulin test, antibody screening test, adsorption and elusion test, and antibody titration in the serum and eluate. The auto IgG warm antibodies were thought to be associated with the EBV infection. This case demonstrates the importance of performing antibody screening and an identification test for transfusion. Transfusion in autoimmune hemolytic anemia is complicated by the presence of pan reactive IgG autoantibodies. However, in this case,the autoantibody was specific for a defined blood group, RhD and RhC antigens,and serocompatible blood was administered without difficulty. Not only transfusion, but also treatment with steroids, a cytotoxic drug and plasmapheresis were critical in the treatment of autoimmune hemolytic anemia.

Rh antigen determination: A marker for erythroid engraftment and proliferation after ABO compatible allogeneic bone marrow transplantation / 대한수혈학회지

BACKGROUNDS: It is useful to estimate the percentage of donor's red cell population in the recipient's blood for determinating the erythroid engraftment and proliferation after allogeneic bone marrow transplantation (BMT). We evaluate the usefulness of Rh antigen determination by flow cytometry and agglutination method for the decision of erythroid engraftment and proliferation after ABO compatible BMT. METHODS: In the case of ABO compatible, Rh mismatched BMT (donor; ccDEE, recipient; Ccdee), the percentage of donor typed red cells was estimated by the flow cytometric analysis using polyclonal anti-D sera during the follow-up period by weekly. At the same time, the agglutination test using polyclonal/monoclonal anti-D sera and monoclonal anti-E sera were performed. RESULTS: At 4th week after BMT, the percentage of RhD positive-donor typed red cells was increased up to 5% in flow cytometric analysis, whereas the agglutination test did not reveal any changes of agglutination in reaction using anti-D and anti-E antibodies. At 5th week after BMT, about 10% of RhD positive cells were identified by flow cytometry, the agglutination test for D and E antigen determination revealed the changes of agglutination strength at first. At 12th week after BMT, 95% of patient's red cells converted RhD positive in flow cytometric analysis. CONCLUSIONS: Rh antigen determinations by flow cytometric analysis and agglutination test are useful to estimate erythroid engraftment and proliferation after ABO compatible BMT.