Immunosuppression therapy carries inherent risks involving the occurrence of infections and neoplasms. Whereas therapeutic advancement have reduced its frequency, encrusted pyelitis reappears in kidney-transplanted patients and may lead to detransplantation. It is related to chronic urological infections and not inevitably favored by endoscopic explorations. Kaposi's sarcoma is the third cause of tumor in renal-transplanted patients. It is rarely multivisceral and develops exceptionally in the transplant. We report the case of a 60 year-old woman who developed an encrusted pyelitis and a Kaposi's sarcoma in a kidney which was transplanted 14 months earlier.