Patient-derived reference intervals for alkaline phosphatase to support appropriate utility for isoenzymes determinations and hypophosphatasia.

Background: Appropriate age- and sex-specific reference intervals for alkaline phosphatase (ALP) are essential to identify patients with hypophosphatasia (low ALP) and to avoid unnecessary ALP isoenzymes analysis (elevated ALP). This study used patient ALP historical data to statistically derive sex- and age-specific reference intervals.

Methods: The ALP values reported as part of clinical management during an 18 month period (from July 2021 to March 2023) were obtained.