Fulminant metastatic calcinosis with cutaneous necrosis in a child with end-stage renal disease and tertiary hyperparathyroidism.

Metastatic calcinosis is a common feature of chronic renal failure. Its first manifestations are bone demineralization and non-visceral and/or visceral calcification with mostly mural deposits in arteries and arterioles. It is initially characterized by hyperphosphataemia followed by secondary or tertiary hyperparathyroidism. Cutaneous involvement is a rare complication. Histologically, the lesions show vascular calcification with ischaemic skin necrosis. Extreme cases may produce calcinosis cutis (calciphylaxis), i.e. disseminated calcification of the subcutaneous tissue and dermis in the form of hard painful cutaneous nodules and plaques with subsequent ulceration. Metastatic calcinosis is a disease affecting adults, while the dystrophic or idiopathic type can develop in children. We present the case of a 6-year-old boy with end-stage renal disease, attributed to congenital renal hypoplasia, and accompanied by secondary hyperparathyroidism. He developed fulminant tertiary hyperparathyroidism and metastatic calcinosis of the lungs, as well as cutaneous necrosis of the buttocks and legs, subsequent to calcification of arteries and arterioles. A maternal renal transplant failed to function. The serum parathormone, calcium and phosphate levels could not be controlled by maintenance dialysis, phosphate binders and calcitriol. Total parathyroidectomy without autotransplantation of parathyroid tissue rapidly returned the serum parathormone, calcium and phosphate levels to normal. In addition, topical treatment using merbromine solution and hydrocolloid dressings, healed the ulcers with significant scar formation, within 2.5 months after parathyroidectomy. A renewed increase of the calcium x phosphate product, 2 months after parathyroidectomy, was attributed to mobilization of calcium compounds from the viscera, as confirmed by a chest X-ray.