Autoimmune hemolytic anemia in pediatric liver or combined liver and small bowel transplant patients: a case series and review of the literature.

BACKGROUND: Autoimmune hemolytic anemia (AIHA) occurring after solid organ transplantation is an infrequently reported entity. We describe in this report six cases of AIHA in pediatric liver or combined liver and small bowel transplant patients. STUDY DESIGN AND METHODS: We retrospectively identified and reviewed the records of pediatric liver or combined liver and small bowel transplant patients with both serologic and clinical evidence of AIHA. We also performed an English language literature review for prior publications of AIHA occurring after solid organ transplantation. RESULTS: We identified six patients presenting with severe hemolysis 9 months to 14 years after transplantation. All six developed warm AIHA, and two had concomitant cold agglutinins. All except one patient received various therapeutic combinations including steroids, intravenous immune globulin, rituximab, plasmapheresis, splenectomy, and vincristine. Five patients achieved remission 2 weeks to 3 months after presentation. Although tacrolimus has been speculated to play a causative role in the development of AIHA after organ transplantation, our case series demonstrated slightly better outcomes despite continuing tacrolimus compared to published cases where most patients either received significantly reduced doses of tacrolimus or were switched to a different immunosuppressant (83% vs. 76% cumulative literature remission rate). CONCLUSION: AIHA may occur in solid organ transplant patients at a much higher frequency than previously believed. Hemolysis is often severe and resistant to steroid treatment alone. Thus early diagnosis and institution of aggressive multimodality treatment, including the use of rituximab, may be needed to achieve remission.