Diagnostic Challenge in Renal Transplantation: Splenosis vs. Post-Transplant Lymphoproliferative Disorder—A Case Report

Abstract

Splenosis is a benign, acquired condition characterized by the auto-implantation of focal deposits of splenic tissue throughout the peritoneal cavity, most commonly occurring after splenic injury and/or splenectomy. Post-Transplant Lymphoproliferative Disorder (PTLD) is a well-known complication of solid organ transplantation that results from unregulated B-cell proliferation due to chronic immunosuppression. Given their clinical and radiologic similarities, these two entities may pose a diagnostic dilemma in select solid-organ transplant recipients. We present the case of a 54-year-old kidney-transplant recipient presenting with abdominal pain and found to have a retroperitoneal soft-tissue mass concerning for PTLD. He underwent a CT-guided biopsy of the mass, and histopathological studies revealed lymphoid tissue consistent with splenic tissue, thus ruling out PTLD. The patient subsequently underwent symptomatic management, with the eventual resolution of his symptoms. The early diagnosis of PTLD is paramount, as prompt intervention has a substantial impact on the high rate of morbidity and mortality associated with this condition. Additionally, the diagnosis of splenosis in the setting of a retroperitoneal mass is critical in order to avoid invasive diagnostic and therapeutic procedures that may result in significant complications. A detailed surgical history, including prior splenic trauma and/or splenectomy, should raise clinical suspicion for splenosis and guide further diagnostic and therapeutic decision making.