Abstract: Objective To compare the positive rate and the cost of modified 56℃ heat elution method and freeze-thaw elution method in detecting ABO hemolytic disease of fetus and newborn (ABO-HDFN), and to discuss the clinical application value of the two methods. Methods All neonatal/umbilical cord blood samples received in our hospital in March 2023 were selected for ABO-HDFN detection (direct anti-human globulin test, free antibody test, elution test), and the elution method was used of modified 56℃ heat elution and freeze-thraw elution simultaneously, the results of the two elution methods were compared and analyzed by specific statistical methods. Results A total of 256 non-O blood type neonatal/umbilical cord blood samples were included for ABO-HDFN detection, of which 145 were type A, 109 were type B and 2 were type AB. The positive rate of modified 56℃ heat elution method was 69.92%, and the freeze-thraw method was 64.45%, there is no statistical difference between the two methods,either in the condition of different blood type, different aggregation intensity and different DAT. Only when free antibody was positive, the modified 56℃ heat elution method was better than the freeze-thraw method. Conclusion There is no statistical difference between the two methods for the diagnostic value of ABO-HDFN in most situations. Each laboratory can choose the method suitable for the laboratory according to the emergency degree of clinical patients, the equipment, consumables configuration, staff experience and time cost of the laboratory.

Key words: ABO hemolytic disease of fetus and newborn (ABO-HDFN), Modified 56℃ heat elution, Freeze-thraw elution, Clinical application