EBV‐Negative Post–Lung Transplant Lymphoma Diagnosed via Paracentesis: A Case Report and Literature Review

Posttransplant lymphoproliferative disorder (PTLD) is a serious complication of solid organ transplantation. While usually Epstein–Barr virus (EBV)–positive PTLD, EBV‐negative PTLD is a distinct, typically late‐onset, and aggressive entity. A 66‐year‐old man developed progressive abdominal distension and anemia 11 years after bilateral lung transplantation for idiopathic pulmonary fibrosis. Paracentesis with flow cytometry of ascitic fluid revealed a monoclonal B‐cell population (CD10, CD19, and CD20 positive). EBV PCR and EBER chromogenic in situ hybridization confirmed EBV negativity, establishing EBV‐negative PTLD. Mycophenolate mofetil was discontinued, and tacrolimus levels were maintained at 6–8 ng/mL. Five additional EBV‐negative PTLD cases after lung transplantation were identified in the literature; most occurred beyond 1 year, were diagnosed by biopsy, and had high mortality. EBV‐negative PTLD is rare and often fatal. Ascitic fluid cytology can facilitate early, minimally invasive diagnosis, warranting high clinical suspicion in transplant recipients with unexplained ascites.