Severe vascular calcification and tumoral calcinosis in a family with hyperphosphatemia: a fibroblast growth factor 23 mutation identified by exome sequencing

Background. Tumoral calcinosis is an autosomal recessive disorder characterized by ectopic calcification and hyperphosphatemia. Methods. We describe a family with tumoral calcinosis requiring amputations. The predominant metabolic anomaly identified in three affected family members was hyperphosphatemia. Biochemical and phenotypic analysis of 13 kindred members, together with exome analysis of 6 members, was performed.