Analysis of Epstein-Barr virus-associated posttransplantation lymphoproliferative disorder after lung transplantation

Background. Epstein-Barr virus (EBV)-associated posttransplantation lymphoproliferative disorder (PTLD) is a serious complication of lung transplantation, Besides immunosuppression the risk factors for PTLD development are largely unknown. Methods. The incidence of PTLD was ascertained in a lung transplant population consisting of 45 patients. Nine patients (20%) experienced PTLD. The clinical, histologic, and human leukocyte antigen (HLA) data were collected on all patients. The incidence of EBV infection in lymphoid tissue taken at the time of engraftment was studied by using EBV in situ hybridization. Results. All patients with PTLD had polymorphous lymphoproliferations, seven of which were polymorphous B-cell hyperplasias and two of which were polymorphous B-cell lymphomas. EBV was identified in all lesions. All patients with polymorphous B-cell hyperplasias had clinically unsuspected disease, five of which were identified at autopsy. The two polymorphous B-cell lymphoma lesions were monoclonal and regressed with immunosuppression reduction. EBV in situ hybridization on donor or recipient lymph nodes obtained at engraftment from the 45 transplant recipients showed no difference in the number of EBV positive cells in patients with and without PTLD. Cyclosporine and azathioprine dosages and cyclosporine levels were similar between patients with and without PTLD. PTLD was seen in patients with high cumulative doses of antilymphocyte globulin. Analysis of HLA status showed a predominance of HLA A2 and DR7 in the donors of the patients with PTLD, whereas donor HLA B7 was more common in patients without PTLD. Conclusions. Detailed studies are necessary to further elucidate the risk factors for PTLD development in the lung transplant population.