Abstract: Objective To analyze the serological characteristics of blood group in patients with autoimmune hemolytic anemia (AIHA) and the therapeutic effect and applications of suspended red blood cells (SRBCs). Methods Fifty-six patients with AIHA hospitalized in our hospital from January 2014 to December 2019 were selected. The serological characteristics of blood group in 56 patients were analyzed retrospectively. The association between positive direct antiglobulin test (DAT), agglutination strength and hemolytic intensity and degree of anemia were analyzed. Patients were divided into three groups: group A (8 cases, with drug), group B (18 cases, with washed RBCs) and group C (30 cases, with SRBCs). The treatment effect and the changes of RBCs, hemoglobin (Hb), reticulocyte (Ret) and total bilirubin (TBIL) were compared before and after treatment. The clinical symptoms and adverse reactions were compared among the three groups. Result Among 56 patients,34 (60.71%) were anti-IgG autoantibodies, 5 (8.93%) anti-C3d autoantibodies and 17 (30.36%) anti- IgG+ C3d mixed autoantibodies. There was significant difference in hemolytic parameters between simple type (IgG, C3d) and complex type (IgG+ C3d) (P<0.05). Fifty-six patients had positive DAT (agglutination strength W + - 4+). Autoantibodies and DAT agglutination strength were positively correlated with hemolysis and anemia (P<0.05). After treatment, Ret% and TBIL were significantly decreased, and RBC and Hb were significantly increased (P<0.05). There was no significant difference in RBC, Hb, Ret and TBIL among the three groups before and after treatment (P>0.05). Based on the total effective rate in group A (87.5%), group B (94.4%), and group C (100%) after treatment, there was no significant difference in the effective rate of complete and partial of clinical symptoms among the three groups (P>0.05). Conclusion The stronger the agglutination intensity of DAT and autoantibody in AIHA patients, the more severity of hemolysis and anemia. AIHA patients treated with SRBCs had definite effect, which could obviously improve lab tests index and improve the patient's anoxia symptom. It has safety, no adverse reactions, and has clinical significance. It is worth popularizing and suitable for clinic.

Key words: AIHA, Blood group serology, Suspended red blood cells, Transfusion efficacy, Transfusion safety