Severe Hypercalcemia in Burkitt Lymphoma Following Heart Transplant in an Elderly Male

Burkitt lymphoma (BL) is a highly aggressive B-cell non-Hodgkin lymphoma (NHL) that rarely occurs as a post-transplant lymphoproliferative disorder (PTLD), especially in the elderly. We report a rare case of BL in a male in his 70s who developed BL several years following heart transplantation in the setting of chronic immunosuppression. He initially presented with signs and symptoms of severe hypercalcemia and retroperitoneal lymphadenopathy, which was biopsied to confirm the diagnosis. Treatment was initiated with rituximab and intrathecal methotrexate; however, his hospital course was complicated by a sigmoid microperforation due to a newly formed colonic fistula. This is an unusual case of Epstein-Barr virus (EBV) reactivation causing PTLD and underscores the importance of considering aggressive lymphomas in immunocompromised elderly patients following solid organ transplantation.