SERUM 25-HYDROXY VITAMIN D;

Abstract

Deficiency of vitamin D is an emerging issue in children worldwide. It has beenobserved that all patients with vitamin D deficiency does not manifest clinical features or hyperparathyroidresponse. In this study we have evaluated the interaction of serum vitamin D level,parathyroid hormone (PTH) level and bone mineral density (BMD) in children. Objectives: Ourobjectives were to determine the frequency of Vitamin D deficiency in children and association oflow serum D level with serum parathyroid level and bone mineral density (BMD). Study Design:Descriptive cross sectional study. Period: June 2012 to May 2014. Setting: Pediatric and Orthopediatricout-patient departments. Material & Methods: A total of 500 children up to 15 yearswith low serum vitamin D level were enrolled to analyze the interaction of Serum vitamin D, PTHand BMD. Patients were divided in groups on the basis of serum PTH. We have categorize thedeficiency of Vitamin D on the basis of level of 25OHD. It was defined as severe (25OHD ≤ 5ng/ml), moderate (25OHD≤ 10 ng/ml) and mild (25OHD ≤ 20 ng/ml) and hyperparathyroidism(SHPT) was valued if level >65 pg/ml. All children with 25OH ≤ 20 ng/ml were included andassociation with SHPT and BMD were measured. Results: It has been observed that 30–40%of patients with moderate and severe deficiency of vitamin D respectively had shown increasedlevel of PTH. Bone mineral density has demonstrated decline pattern from PTH Quartile 1toQuartile 4 at all sites in children, with only minimal difference (decreasing trend) in serum25OHD levels between these quartiles. The critical level of parathyroid hormone beyond whichBMD going to decline is 35 pg/ml. No demonstrable difference has been observed in BMDwithin each PTH quartile according to categorization of Vitamin D Deficiency. Conclusions:Around 40% of the patients having low serum vitamin D level demonstrated SHPT. Regardingthe BMD levels, it begins to decreases at PTH levels currently well thought-out to be normal.So there is a need to re-define SHPT among different age groups considering the relationshiplinking PTH and BMD. This may also affect guidelines regarding vitamin d supplementation inpatients with vitamin D deficiency.