Posttransplant lymphoproliferative disease in a child: clinical and molecular characterization.

We report a 12-year-old girl suffering from end-stage renal disease due to focal-segmental sclerosis and retardation of statomotoric and mental development of unknown origin. Renal transplantation (TX) was performed 7 months after initiation of peritoneal dialysis at the age of 11 years. Immunosuppressive therapy included cyclosporine A, mycophenolate mofetil and methylprednisolone. The patient developed spiking fever up to 40 degrees C without signs of infection 10 months after TX. Kidney function remained stable but ultrasound examination and CT-scan showed hypodense masses within both liver and spleen. Epstein-Barr virus (EBV) polymerase chain reaction (PCR) results with a high number of copies (20 x 10(6) copies/ml blood) against the background of a previous EBV infection (IgG positive, IgM negative) made the diagnosis of EBV-reactivation likely. Splenectomy was performed. Examination of the spleen showed EBV-associated polymorphic posttransplant lymphoproliferative disease (PTLD) with predominant B cell proliferation and monoclonal VH3-rearrangement of the IgG heavy chain locus. Therapy with acyclovir was introduced and immunosuppression was reduced. No rejection episode occurred. Body temperature normalized and the patient recovered over a 3-month period. EBV-PCR in plasma was negative (0.02 x 10(6) copies/ml blood) 12 weeks after reduction of immunosuppression. The liver masses completely resolved after 27 months. After a total follow-up of 36 months the child remains in good health.