A rare, inherited, and sometimes fatal metabolic bone disease characterized by poor bone mineralization and profound skeletal defects.Hypophosphatasia (HPP) is a rare disease. The worldwide prevalence is unknown.
The frequency of severe HPP in live births is estimated at 1:100,000. The frequency of mild HPP is more challenging to assess because the symptoms may escape notice, or be misdiagnosed. The highest incidence of HPP has been reported in the Mennonite population in Manitoba, Canada, where one in every 2,500 newborns manifests severe disease.