Adult hypophosphatasia manifests in a marathon runner. Issue 9 (9th September 2020)

• Record Type: Journal Article
• Authors: Fanous, Nada; Barb, Diana
• Is Part Of: BMJ case reports. Volume 13:Issue 9(2020)
• Publication Date: 2020-09-09
• Subjects: calcium and bone -- sports and exercise medicine; Medicine -- Case studies -- Periodicals; 610.5
• DOI: 10.1136/bcr-2020-234764
• Languages: English
• ISSNs: 1757-790X

Abstract

Abstract : A 49-year-old woman, previously healthy, presented with recurrent fractures provoked by minimal trauma. She had sustained seven fractures over the previous 2 years. While she was an avid runner, her injuries were determined to be out of proportion to the degree of trauma. Initial evaluation, exploring the more common causes such as low bone density and abnormal vitamin D metabolism, was unremarkable. On repeat of the some of the tests, a low alkaline phosphatase (AP) was noted, which raised suspicion for hypophosphatasia (HPP), a rare cause of recurrent fractures. Subsequent workup revealed a low bone-specific AP and elevated vitamin B6 . Subsequently, genetic testing confirmed the diagnosis of adult-onset HPP caused by a heterozygous mutation c.407G>A in the ALPL gene. Asfotase alfa was started; however, the patient developed an allergic reaction leading to the discontinuation of the drug.