Novel insights from a large cohort: Elucidating incidence, risk factors, treatment, and prognostic predictors in autoimmune hemolytic anemia after allogeneic hematopoietic stem cell transplantation

Background and Objectives: Autoimmune hemolytic anemia (AIHA) is a rare but serious complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Current understanding of post-allo-HSCT AIHA remains insufficient. This study aimed to elucidate the features and significant predictors of post-allo-HSCT AIHA to guide precise clinical management. Methods: A retrospective nested case-control study was conducted at Peking University People's Hospital from 2013 to 2024. A total of 61 patients with post-allo-HSCT AIHA were enrolled. For each case, three AIHA-free allo-HSCT recipients were randomly matched by sex, age (± 3 years), and transplant timing (± 3 months). Treatment modalities and responses of AIHA patients were analyzed. Cox regression analyses were employed to identify risk factors for post-allo-HSCT AIHA, as well as predictors of AIHA relapse and patient mortality. Results: = 0.031) were associated with an increased risk of mortality. Conclusions: This study provides novel insights into post-allo-HSCT AIHA. These findings highlight key prognostic markers, guiding risk stratification and the management of AIHA after allo-HSCT.