Clinical variability of hypophosphatasia in colombian patients: Case reports

Hypophosphatasia (HPP) is a rare inherited disorder characterized by low serum alkaline phosphatase. It affects bone and tooth min-eralization, although extra-skeletal manifestations are frequent. HPP is caused by loss-of-function mutations in the ALPL gene, encoding the protein tissue-nonspecific alkaline phosphatase. The phenotype is broadly variable, from a subtype with exclusive odontological com-promise (odontohypophosphatasia) to five subtypes with systemic in-volvement, classified according to the age of onset at first symptoms. We present seven cases of HPP, in order to perform the clinical, bio-chemistry and radiological description of these Colombian patients, as well as to show the clinical variability of the disease in patients who present the same mutation or genetic defect.