Effect of Vitamin D Treatment on Dynamics of Stones Formation in the Urinary Tract and Bone Density in Children with Idiopathic Hypercalciuria

Abstract

Vitamin D supplementation in patients with urolithiasis and hypercalciuria is considered to be unsafe. We analyzed the impact of vitamin D supplementation on selected health status parameters in children with idiopathic hypercalciuria. The study included 36 children with urolithiasis resulting from excessive calcium excretion. The level of calcium and 25(OH)D (hydroxylated vitamin D - calcidiol) in serum, urinary calcium excretion and the presence of stones in urinary tract were assessed prospectively. Blood and urine samples were collected at the time when the patient was qualified for the study and every three months up to 24 month of vitamin D intake at a dose of 400 or 800 IU/day. At time zero and at 12, and 24 months of vitamin D supplementation, densitometry was performed. Supplementation with vitamin D caused a statistically significant increase in the concentration of 25(OH)D in serum. There were no significant changes in calcium concentration in serum, excretion of calcium in urine but also in bone density. There was no significant increase in the risk of formation or development of stones in the urinary tract. Supplementation with vitamin D (400–800 IU/day) in children with idiopathic hypercalciuria significantly increases 25(OH)D concentration, does not affect calciuria, but also does not improve bone density.

Infantile urolithiasis

“…Fallahzadeh et al [14] found serum levels of 25(OH)-vitamin D to be significantly higher in the infants with urolithiasis than in the controls, as well as positive correlation between serum levels of 25(OH)-vitamin D and serum calcium. Milart et al [24], studying children with hypercalciuria, observed a rise in serum 25(OH)-vitamin D following supplementation with vitamin D but no increase in calcium excretion. An extensive literature search concluded that the effect of oral vitamin D on urine calcium may vary between populations [23].…”

Beyond kidney stones: Why pediatricians should worry about hypercalciuria

“…The genetic background is also involved in the pathogenesis of IH. It has been described that patients with UL due to hypercalciuria can be carriers of genetic polymorphisms that encode certain proteins involved in the tubular reabsorption of calcium and phosphate (VDR, SLC34A1, SLC34A4, CLDN14, CaSR, TRPV6), or in the prevention of it precipitation of calcium salts (CaSR, MGP, OPN, PLAU, UMOD)[ 67 - 69 ]. Garcia Nieto et al [ 23 ] published a summary with all the pathophysiological mechanisms involved in IH described to date (Figure 1 ).…”

“…This supplementation has been related to hypercalciuria. Milart et al [ 69 ] analyzed the impact of vitamin D supplementation on 36 children with IH and UL prospectively. Blood and urine samples were collected every three months up to 24 mo of vitamin D intake at a dose of 400 or 800 IU/d.…”

Vitamin D in 2020: An Old Pro-Hormone with Potential Effects beyond Mineral Metabolism

“…Interventional studies showed no effect of cholecalciferol on body weight reduction in obese children participating in a weight management program [14], or on bone mineral density in children with hypercalciuria [15]. This last study emphasizes the safety of vitamin D treatment (400-800 IU/day) on calciuria and on the evolution of stones in the urinary tract in these children [15]. In post-menopausal women, ergocalciferol 40,000 IU/week did not change vulvovaginal atrophy compared to placebo, but improved vaginal pH and visual analog scale of vulvovaginal atrophy symptoms between baseline and 12 weeks in the vitamin D group [16].…”

“…Regarding 25OHD assessment, it is specified that the detection of 3-Epi25(OH)D 3 using liquid chromatography-tandem mass spectrometry prevents the overestimation of 25OHD and misclassification of vitamin D status [11]. Interventional studies showed no effect of cholecalciferol on body weight reduction in obese children participating in a weight management program [14], or on bone mineral density in children with hypercalciuria [15]. This last study emphasizes the safety of vitamin D treatment (400-800 IU/day) on calciuria and on the evolution of stones in the urinary tract in these children [15].…”