Parathyroid hormone-related peptide (
PTHrP) is expressed at a wide range of sites in the body and performs different functions including vasodilation, relaxation of smooth muscle cells, and regulation of bone development.
PTHrP also mediates
hypercalcemia related to neoplastic diseases. However, reference ranges specific method and age were not evaluated. We establish
PTHrP reference ranges in apparently healthy, normocalcemic, normophosphatemic pediatric individuals. In this observational prospective, study we measured
PTHrP in serum from 178 samples (55.06% male 44.94% female) from apparently healthy pediatric subjects [median age 10 years (range 1-18)] subunit ELISA method The statistical analysis performed provided for the calculation of the 95% reference interval, right-sided, with a non-parametric percentile method (CLSI C28-A3). Upper reference limits (URL) for
PTHrP was 2.89 ng/mL (2.60 to 3.18; 90% CI). No significant differences were found between the median
PTHrP concentrations in males vs females and in the age range categories selected. Comprehensive normal values for
PTHrP are indispensable to the assessment of
calcium phosphorus dysfunction in children. Severe
hypercalcemia is a rare, but clinically significant condition, in infancy and childhood.
PTHrP values higher than the reference value may help to distinguish the hypercalcemic product of a
malignancy,
paraneoplastic syndromes mediated by
PTHrP, from other causes.