Case report: successful treatment of posttransplant lymphoproliferative disorder and quiescence of dermatomyositis with rituximab and sirolimus.

Posttransplant lymphoproliferative disorder (PTLD) remains one of the most important complications of intensive immunosuppressive therapy. A 65-year-old Caucasian woman received a primary en bloc kidney transplant from a deceased 2-year-old donor. After antithymocyte globulin induction she was treated with a maintenance regimen including cyclosporine and mycophenylate mofetil (MMF). She had a history of recurrent dermatomyositis, suggesting a flawed immune system. After a benign course for 9 months and after an increase in MMF from 2 to 3 g daily, she presented with pneumonia owing to Candida albicans, which was responsive to antibiotics, as was the PTLD. Persistent fever led to a diagnosis of PTLD. The immunosuppressive regimen was converted to sirolimus (SRL) and rituximab, with over 90% necrosis of the neoplasm at 1 month. However, owing to concern at exploration, the allografts were extirpated. This case documented the benefit of the rituximab-SRL combination to treat PTLD while maintaining dermatomyositis in remission.