ESPE Abstracts

Background: Parathyroid Hormone (PTH), a key regulator of calcium and phosphorus homeostasis through its effect on bone, kidney, and intestine. The serum concentration of PTH is derived both from the release of PTH stored in secretory granules and from de novo synthesis of PTH in response to alterations in the serum levels of calcium, phosphorus, and vitamin D. Magnesium has a potent role in secretion of PTH, while alkaline phosphatase appears to be important biochemical marker of bone formation and involving in PTH disorders.

Method: A cross-sectional study was conducted in 80 children aged 2 – 5 years old with level of vitamin 25(OH)D < 30 ng/mL. Anthropometric and laboratory test including magnesium (Mg), calcium (Ca), phosphorus (Ph) and alkaline phosphatase (ALP) level were assessed. The reference values of vitamin 25(OH)D used in the present study were as follows: <20 ng/ml (deficiency), 20-29 ng/ml (insufficiency), 30-100 ng/ml (sufficiency), and > 100 ng/ml (increased). Anthropometrics were evaluated using WHO child growth standards.

Results: From 80 children included, the age means value 3,53 ± 0,90 years with minimal age in 2 years and maximal age in 5 years, consist of 37 (46,3%) boys and 43 (53,8%) girls. According to WHOCGS: 32 (40%) were stunted (height/age < -2SD), 31 (38.8%) were severely stunted and 17 (21.3%) were normal with mean BMI (body mass index) value 15,23±1,25. There are no signs and symptoms of mineral bone disorders found in all subjects. Children with insufficient vitamin D had PTH level was inversely associated with vitamin D and level of minerals as follow: vitamin 25(OH)D (r = 0.877; P<0.05), Mg (r = 0.890; P<0.05), Ca (r = 0.972; P<0.05), Ph (r = 0.897; P<0.05). PTH level was positively correlated with ALP (r = 0,965; P<0,05).

Conclusion: In children with Vitamin D insufficiency may not exhibit obvious symptoms and signs except various stature including normal and short stature. Nevertheless, levels of PTH, magnesium, calcium, phosphate and alkaline phosphatase were shifted.