SUMMARYThe case studies of four patients with post-transplantation calcinosis are presented. Three of the four patients died of inanition and sepsis secondary to infection of extensive soft tissue ulcers and diffuse cutaneous vascular calcification with gangrene. The fourth patient survived following removal of all four parathyroid glands and autografting of approximately one-half of one gland. Common to the patients was secondary hyperparathyroidism, elevated mean serum calcium levels after transplantation, and radiographie evidence of small and medium vessel calcification. No other differences could be found between these patients and other patients with post-transplantation hyperparathyroidism without calcinosis. In the face of apparently minor complaints of lower extremity discomfort, elevated parathyroid hormone levels (PTH) and positive xerography may indicate subtotal parathyroidectomy regardless of the serum calcium level.