Metastatic Calcification

A patient with metastatic calcification is presented and the contributions of plain film, computed tomography, and bone scintigraphy in the diagnosis are discussed. The patient had a long history of end-stage renal failure, and was previously receiving peritoneal dialysis and calcium supplements. His serum calcium level had been persistently elevated for several years without correction. Recently, the patient complained of generalised bone pain and dyspnoea. Chest radiography at presentation showed diffuse pulmonary calcification. He was subsequently referred for a bone scan examination to exclude osteomyelitis given his markedly elevated alkaline phosphatase levels. Widespread distribution of abnormal radiotracer uptake in multiple organs was seen at technetium 99m hydroxymethylene diphosphonate bone scan, consistent with metastatic calcification. Further biochemical and histological investigations revealed persistent hypercalcaemia and hyperparathyroid bone disease, while non-enhanced computed tomography scanning and high-resolution computed tomography scanning of the thorax showed characteristic chest wall vascular calcification and parenchymal calcification.