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.