HPPの診断
アルカリフォスファターゼ（ALP）の活性低下で、HPPは鑑別できます。ALP活性低下とともに、骨格系または全身の特徴的所見が認められれば、HPPを強く疑います1,2
一般的な血液検査でALP活性低下は確認することができます1,2
HPP患者さんでは通常、ALP活性が年齢別基準値の正常下限値を下回ります1,2
早期の正確な診断が重要です
診断の遅れが、症状を悪化させ、生命を脅かす症状を引き起こすことがあります1,3,6,7
HPPが見過ごされ、適切でない治療が行われた場合、症状が悪化する可能性があります1-4
よくある見過ごしを回避する
HPPの臨床症状は、一般的な骨系統疾患と類似することから、見過ごされることがよくあります1,2
References: 1. Rockman-Greenberg C. Hypophosphatasia. Pediatr Endocrinol Rev. 2013;10(suppl 2):380-388. 2. Mornet E, Nunes ME. Hypophosphatasia. In: Pagon RA, Bird TD, Dolan CR, Stephen K, eds. GeneReviews. Seattle, WA: University of Washington, Seattle; 1993. http://www.ncbi.nlm.nih.gov/books/NBK1150/. Published November 20, 2007. Updated August 5, 2010. Accessed March 31, 2014. 3. Mohn A, De Leonibus C, de Giorgis T, Mornet E, Chiarelli F. Hypophosphatasia in a child with widened anterior fontanelle: lessons learned from late diagnosis and incorrect treatment. Acta Paediatr. 2011;100(7):e43-e46. 4. Sutton RAL, Mumm S, Coburn SP, Ericson KL, Whyte MP. “Atypical femoral fractures” during bisphosphonate exposure in adult hypophosphatasia. J Bone Miner Res. 2012;27(5):987-994. 5. Cundy T, Michigami T, Tachikawa K, Dray M, Collins J. Phenotypic change in a patient with hypophosphatasia with the onset of renal failure. Paper presented at: 40th Annual Congress of the European Calcified Tissue Society (ECTS); May 18-21, 2013; Lisbon, Portugal. 6. Baumgartner-Sigl S, Haberlandt E, Mumm S, et al. Pyridoxine-responsive seizures as the first symptom of infantile hypophosphatasia caused by two novel missense mutations (c.677T>C, p.M226T; c.1112C>T, p.T371I) of the tissue-nonspecific alkaline phosphatase gene. Bone. 2007;40(6):1655-1661. 7. Whyte MP, Greenberg CR, Kishnani PS, et al. Fracture burden in children and adults with hypophosphatasia. Poster presented at: 39th Annual Congress of the European Calcified Tissue Society (ECTS); May 19-23, 2012; Stockholm, Sweden.