Literature review of occurrence, effectiveness, safety, and hospitalization burden of blood transfusion in the management of warm autoimmune hemolytic anemia.

Introduction: Cases of warm autoimmune hemolytic anemia (wAIHA) often present with life-threatening levels of hemoglobin requiring red blood cell (RBC) transfusion support.

Aim: This literature review assessed the occurrence, safety, effectiveness, and hospitalization burden of RBC transfusions in the management of patients with wAIHA.

Methods: Electronic databases (Embase, MEDLINE) were searched from inception to December 2021 along with additional searches conducted up to March 2024.

Results: Of the 1478 articles screened, 17 observational studies and reviews were included. These studies demonstrated the use of 1-50 red blood cell transfusions to reach clinically acceptable hemoglobin levels in patients with wAIHA. In general, pre-transfusion hemoglobin levels were 6 g/dL and increased by an average 1.2 g/dL following a transfusion. Approximately 50% of patients with primary or secondary wAIHA suffered relapses. No data was available to distinguish between RBC transfusions used at initial presentation versus during relapse. Five studies found no increase in hemolysis or serious adverse reactions following transfusions and two studies reported mild transfusion-related adverse effects. Limited data was available regarding the hospitalization burden of RBC transfusion. Patients with wAIHA requiring transfusions had a median hospital stay from 15 to 17 days, which is considerably higher than all causes hospitalization of 4.5 days for 2023 U.S.

Conclusion: In patients with wAIHA, data supports wide variability in occurrence, but relative safety and effectiveness of RBC transfusions as supportive therapy. Additional studies are needed to assess the occurrence, safety, and hospitalization burden of RBC transfusions relative to other therapies in chronic relapsing wAIHA.