Premature loss of baby teeth with root intact, 2 nontraumatic fractures in his teenage years, kidney stone 2 years ago, ALP value reported as 30 U/L* on lab results 2 years ago.
Persistently low age- and sex-adjusted alkaline phosphatase (ALP) levels can be the key to identifying HPP in some hard-to-diagnose patients.1,2
Multinational observational, prospective Global HPP Registry study conducted in children (N=121; ≥18 years) from January 2015 - September 2017.
*Excludes patients aged <2 years at enrollment.
†Excludes patients aged <6 months at enrollment.
In HPP, low alkaline phosphatase activity leads to an accumulation of pyridoxal 5’-phosphate (PLP) in the systemic circulation resulting in a deficiency of vitamin B6 in the central nervous system, which can cause seizures (which is most common in infants)1
Patient image is hypothetical.
In adulthood, mineralization deficits can lead to risk for osteopenia and osteoporosis and to increased risk of fracture.9
Decreased bone mass in childhood may lead to a higher rate of fractures in adulthood.7
*Data from a multinational noninterventional, retrospective chart review study designed to understand the natural history of 48 patients ≤5 years of age with severe perinatal- and infantile-onset HPP. Patients included in the study were those diagnosed with HPP based on at least one of the following: serum biomarker levels (below-normal ALP and above-normal PLP or PEA), below-normal ALP and radiographic abnormalities, and/or genetic analysis of the ALPL gene. Additionally, onset of HPP must have occurred prior to 6 months of age based on signs that included at least one of the following: respiratory compromise, rachitic chest deformity, and/or vitamin B6–responsive seizures.2
†Data from a retrospective, multinational, noninterventional natural history study of childhood HPP in patients 5 to 15 years of age (N=32). 3
‡Combined data from HIPS/HOST, an Internet questionnaire and telephone survey that queried demographics, HPP-related illness history, disease progression, and health-related quality of life. One hundred twenty-five adults participated.4
What is considered “low ALP” in children varies across ages and sexes.
References: 1. Rockman-Greenberg C. Pediatr Endocrinol Rev. 2013;10(suppl 2):380-388. 2. Bianchi ML, et al. Osteoporos Int. 2020;31(8):1445-1460. doi: 10.1007/s00198-020-05345-9 3. Hӧgler W, et al. BMC Musculoskelet Disord. 2019;20(1):80. doi: 10.1186/s12891-019-2420-8 4. Colantonio DA, et al. Clin Chem. 2012;58(5):854-868. doi: 10.1373/clinchem.2011.177741 5. McKiernan FE, et al. J Bone and Miner Res. 2014;29(7):1651-1660. doi: 10.1002/jbmr.2178 6. Bishop N, et al. Arch Dis Child. 2016;101(6):514-515. doi: 10.1136/archdischild-2015-309579 7. Davies JH, et al. Arch Dis Child. 2005;90(4):373-378. doi: 10.1136/adc.2004.053553 8. Clarke J, et al. Accessed August 31, 2021. http://www.statcan.gc.ca/pub/82-624-x/2016001/article/14637-eng.pdf 9. Maggioli C, et al. Ann Pediatr Endocrinol Metab. 2017;22(1):1-5. doi:10.6065/apem.2017.22.1.1 10. Whyte MP, et al. J Pediatr. 2019;209:116-124:e4. doi: 10.1016/j.jpeds.2019.01.049 11. Whyte MP, et al. A retrospective, multi-national, non-interventional, natural history study of the childhood form of hypophosphatasia. Presented at: the Endocrine Society’s 97th Annual Meeting and Expo; March 15, 2015; San Diego, CA. 12. Weber TJ, et al. Metabolism. 2016;65(10):1522-1530. doi: 10.1016/j.metabol.2016.07.006