Effect of vitamin D repletion on urinary calcium excretion among kidney stone formers

Clin J Am Soc Nephrol. 2012 May;7(5):829-34. doi: 10.2215/CJN.11331111. Epub 2012 Mar 15.


Background and objectives: Despite the important role of vitamin D in maintaining bone health, many clinicians are reluctant to treat vitamin D deficiency in kidney stone formers because of the theoretical risk of increasing urinary calcium excretion. This study examined the effect of vitamin D repletion on urinary calcium excretion among stone formers.

Design, setting, participants, & measurements: Participants (n=29) were recruited from urology clinics affiliated with New York Presbyterian Hospital. Enrollment criteria included a history of nephrolithiasis, urinary calcium excretion between 150 and 400 mg/d, and a serum 25-hydroxyvitamin D level <30 ng/ml. Participants were given oral ergocalciferol (50,000 IU/wk) for 8 weeks. Serum and 24-hour urine tests were repeated after 8 weeks.

Results: Levels of 25-hydroxyvitamin D increased significantly after vitamin D repletion (17±6 and 35±10 ng/ml, P<0.001), but mean 24-hour urinary calcium excretion did not change (257±54 and 255±88 mg/d at baseline and follow-up, respectively, P=0.91). However, 11 participants had an increase in urinary calcium excretion ≥20 mg/d; these participants also had an increase in urine sodium excretion, likely reflecting dietary variability. No participant experienced adverse effects from vitamin D, including hypercalcemia.

Conclusions: Among stone formers with vitamin D deficiency, a limited course of vitamin D repletion does not seem to increase mean urinary calcium excretion, although a subset of individuals may have an increase. These data suggest that vitamin D therapy, if indicated, should not be withheld solely on the basis of stone disease, but 24-hour urinary calcium excretion should be monitored after repletion.

Publication types

  • Clinical Trial

MeSH terms

  • Adult
  • Calcium / urine*
  • Ergocalciferols / adverse effects
  • Ergocalciferols / pharmacology*
  • Ergocalciferols / therapeutic use
  • Female
  • Humans
  • Kidney Calculi / complications
  • Kidney Calculi / urine*
  • Linear Models
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Parathyroid Hormone / blood
  • Sodium / urine
  • Statistics, Nonparametric
  • Vitamin D / analogs & derivatives
  • Vitamin D / blood
  • Vitamin D Deficiency / blood
  • Vitamin D Deficiency / complications
  • Vitamin D Deficiency / drug therapy*
  • Vitamins / adverse effects
  • Vitamins / pharmacology*
  • Vitamins / therapeutic use


  • Ergocalciferols
  • Parathyroid Hormone
  • Vitamins
  • Vitamin D
  • Sodium
  • 25-hydroxyvitamin D
  • Calcium