Refractory Autoimmune Hemolytic Anemia Following Hematopoietic Stem Cell Transplant (Hsct) In The Setting Of Impaired Immune Reconstitution Among Pediatric Hsct Recipients

Background: Autoimmune hemolytic anemia is a well-recognized complication of hematopoietic stem cell transplant (HSCT). While occurring in only ~2-6% of pediatric patients receiving HSCT, it is associated with significant morbidity and mortality of up to 50%. Post-transplant AIHA is poorly studied due to small patient numbers. Therefore, risk factors for the development of post-transplant AIHA are not well delineated and optimal treatment strategies are not known. Disease course is often refractory and multiply relapsing, with current treatment approaches remaining empiric. The most commonly utilized immunomodulatory therapies include glucocorticoids, intravenous immune globulin (IVIG), and rituximab; and potentially repeat bone marrow transplantation. Better understanding of the underlying immunobiology in post-transplant AIHA is imperative, as it may uncover the potential for newer, more effective targeted treatment options and better elucidate pre-disposing risk factors which could be modified for future HSCT patients, resulting in overall improvement in clinical outcomes among this group of high-risk patients.