Incidence, Risk Factors, and Treatment of Autoimmune Cytopenia Following Pediatric Allogeneic Hematopoietic Stem Cell...

Autoimmune cytopenia (AIC) following pediatric allogeneic hematopoietic stem cell transplantation (allo-HSCT) is relatively rare but it is a challenging complication, and standardized treatment guidelines are lacking. We retrospectively analyzed 436 pediatric patients undergoing allo-HSCT; 37 (8.5%) developed AIC, characterized by autoimmune hemolytic anemia (n = 13), immune thrombocytopenia (n = 11), and Evans syndrome (n = 13). Risk factor analysis revealed that younger age at HSCT, nonmalignant diseases, unrelated donor transplantation, and chronic graft-versus-host disease (cGVHD) were significantly associated with the development of AIC. Through multivariate analysis, cGVHD was identified as an independent risk factor for AIC. In our study, the first-line treatment for AIC involved steroids and/or intravenous immunoglobulin, with a complete remission rate of 48.6%. Additional therapeutic strategies included rituximab, which led to complete remission in 5 of 12 patients we treated, and sirolimus, with 3 of 7 patients achieving complete remission. Three patients achieved partial remission, while 9 patients died due to complications, such as severe infections, extensive GVHD, and multiorgan bleeding. Our findings suggest that cGVHD is an independent risk factor for post-transplant AIC and is typically associated with adverse outcomes, highlighting the critical importance of timely and effective interventions.