The authors describe a new complication observed in patients after transplantation of the kidneys, characterized by intensive periarticular pain of the joints of the lower extremities, mostly with a symmetrical affection of the heels and knees, associated with vasomotor changes in the affected area, X-ray evidence of patchy osteoporosis and an increased periarticular activity of radionuclide on bone scans. The symptoms develop shortly after transplantation and recede within several months. The clinical findings, X-ray and scintigraphic changes are typical for the syndrome of reflex sympathetic dystrophy. The etiology of the syndrome remains obscure, the symptomatology recedes parallel with reduction of the dosage and levels of cyclosporin A.