Post-transplant lymphoproliferative disorder--case reports of three children with kidney transplant.

INTRODUCTION: Post-transplant lymphoproliferative disorder (PTLD) is a heterogeneous group of diseases, characterized by abnormal lymphoid proliferation following transplantation. It is a disease of the immunosuppressed state, and its occurrence is mostly associated with the use of T-cell depleting agents, and also intensification of immunosuppressive regimens. In the majority of cases, PTLD is a consequence of Epstein-Barr virus (EBV) infection and is a B-cell hyperplasia with CD-20 positive lymphocytes. The 2008 World Health Organization classification for lymphoid malignancies divides PTLD into four major categories: early lesions, polymorphic PTLD, monomorphic PTLD and Hodgkin PTLD. The treatment and prognosis depend on histology. The cornerstone of PTLD therapy includes reduction/withdrawal of immunosuppression, monoclonal anti CD-20 antibody (rituximab) and chemotherapy.

OUTLINE OF CASES: We reported here our experiences with three patients, two girls aged 7.5 and 15 and a 16-year old boy. They had different organ involvement: brain, combined spleen-liver and intestines, respectively. Even though EBV was a trigger of lymphoid proliferation as it was confirmed by histopathology or in cerebrospinal fluid, qualitative EBV-PCR was positive only in one patient at disease presentation. Reduction of immunosuppression therapy was applied in treatment of all three patients, while two of them received rituximab and ganciclovir. They had an excellent outcome besides many difficulties in diagnosis and management of disease.

CONCLUSION: Qualitative EBV-PCR is not useful marker in pediatric transplant recipients. Our suggestion is that patients with the risk factors like T-cell depleting agents, immunosuppressant protocol or increasing immunosuppressive therapy and EBV miss-match with donor must be more accurately monitored with quantitative EBV PCR.