[Calcifications and phosphocalcic metabolism].

Extraosseous calcifications correspond to ubiquitous deposits of intra-tissue calcium salts leading to dysfunction of the affected tissue or organ. There are two types: metastatic calcifications and dystrophic calcifications. Their formation mechanism is by mimicking the physiological mineralization process with an "osteoblast-like" cell. The cause of extra-osseous calcification is variable and depends on risk factors. If the subject is young, you will have to think about a genetic syndrome!