EBV‐Negative Burkitt Lymphoma Following Pediatric Liver Transplantation in a Child With Maple Syrup Urine Disease

Background Maple Syrup Urine Disease (MSUD) is a genetic metabolic disorder requiring dietary protein restriction. Liver transplantation corrects the metabolic defect but carries a risk of post‐transplant lymphoproliferative disorder (PTLD), often associated with Epstein–Barr virus (EBV) infection. EBV‐negative PTLD is rare, and optimal management remains uncertain. Case Presentation A 7‐year‐old boy with classical MSUD underwent living donor liver transplantation at 15 months. Five years later, he developed progressive cervical lymphadenopathy. Lymph node biopsy revealed CD10‐, CD20‐, and MYC‐positive atypical lymphoid cells consistent with post‐transplant Burkitt lymphoma. EBV studies, including PCR and EBER in situ hybridization, remained negative throughout. The disease was staged as Murphy/St. Jude stage IV with bone marrow involvement. Chemotherapy followed the B‐NHL03 protocol with rituximab. Tacrolimus (FK‐506) was reduced to 1.0 ng/mL during treatment and temporarily withheld during febrile neutropenia. Interstitial nephritis resolved after treatment cessation. Post‐therapy imaging confirmed complete remission, and liver biopsy showed no evidence of rejection. Five years after completing therapy, the patient remains disease‐free with stable graft function and metabolic control. Conclusion This rare EBV‐negative post‐transplant Burkitt lymphoma underscores the need to clarify its prognostic significance and optimize treatment strategies for pediatric PTLD.