Multifocal Epstein-Barr Virus-Negative Posttransplantation Lymphoproliferative Disorder Treated With Reduction of Immunosuppression.

Posttransplantation lymphoproliferative disorder (PTLD) is associated with significant mortality in kidney transplant recipients. PTLD cases associated with poor prognostic factors that are refractory to reduction of immunosuppression generally require chemotherapy and immunotherapy. We present a patient with PTLD who achieved complete remission after reduction of immunosuppression alone despite having a poor prognosis. A boy with a mutation in the WT1 gene developed bilateral Wilms tumor at 15 months and received a kidney transplant at the age of 4 years. At 13 years of age, the patient's condition was managed with methylprednisolone, tacrolimus, and mycophenolate mofetil. He developed Epstein-Barr virus-negative monomorphic PTLD with numerous nodular lesions in the liver, vertebral bodies, and gastric wall. To reduce immunosuppression, we discontinued mycophenolate mofetil treatment, decreased tacrolimus dosage to 1mg/d, and increased methylprednisolone dosage to 2mg/d. The PTLD lesions drastically diminished in size within several days and disappeared 144 days after reduction of immunosuppression, although the patient had several factors indicating a poor prognosis. As of 13 months after reduction of immunosuppression for PTLD, the transplanted kidney was still functional. We conclude that even when patients with PTLD have a poor prognosis, reduction of immunosuppression alone may result in complete remission when the early response is excellent.