title: Osteomalacia with low alkaline phosphatase: a not so rare condition with important consequences.
abstract: Hypophosphatasia is a genetic disorder, characterised by a dysfunctional tissue-non-specific isoenzyme of alkaline phosphatase that impacts bone metabolism and predisposes to osteomalacia or rickets. The clinical presentation is very diverse, depending on the age of onset and the severity of the disease. Several forms of hypophosphatasia are recognised. We present a case of a 50-year-old woman with low impact fractures and loss of teeth at a young age. She also had a low alkaline phosphatase and was diagnosed with adult hypophosphatasia. Although the severe forms of hypophosphatasia are rather rare, the adult form is thought to occur quite frequently. As this condition is not well known by healthcare professionals, the time to diagnosis and initiation of adequate treatment is often postponed. When encountering a patient with low alkaline phosphatase, low bone density or a history of bone fractures, the possibility of hypophosphatasia should be considered.
authors.affiliation: Department of Endocrinology, Universitair Ziekenhuis Brussel, Brussels, Belgium.
authors.forename: Jamal
authors.initials: J
authors.lastname: Belkhouribchia
authors.affiliation: Department of Endocrinology, Universitair Ziekenhuis Brussel, Brussels, Belgium.
authors.forename: Bert
authors.initials: B
authors.lastname: Bravenboer
authors.affiliation: Department of Genetics, Universitair Ziekenhuis Antwerpen, Edegem, Belgium.
authors.forename: Marije
authors.initials: M
authors.lastname: Meuwissen
authors.affiliation: Universitair Ziekenhuis Brussel, Brussels, Belgium.
authors.forename: Brigitte
authors.initials: B
authors.lastname: Velkeniers
mesh_terms: D000469:Alkaline Phosphatase / Q000097:blood* / Q000235:genetics; D050071:Bone Density Conservation Agents / Q000008:administration & dosage; D002118:Calcium / Q000008:administration & dosage; D004252:DNA Mutational Analysis; D019587:Dietary Supplements; D005260:Female; D050723:Fractures, Bone / Q000209:etiology* / Q000517:prevention & control; D005598:Fractures, Spontaneous / Q000209:etiology* / Q000517:prevention & control; D006801:Humans; D007014:Hypophosphatasia / Q000097:blood / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology; D008875:Middle Aged; D020125:Mutation, Missense; D010018:Osteomalacia / Q000097:blood / Q000175:diagnosis* / Q000503:physiopathology; D016896:Treatment Outcome; D014807:Vitamin D / Q000008:administration & dosage; D014808:Vitamin D Deficiency / Q000188:drug therapy
chemical_list: D050071:Bone Density Conservation Agents; D014807:Vitamin D; D000469:Alkaline Phosphatase; D002118:Calcium
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