Vitamin D Repletion in Stone Formers With Hypercalciuria
Condition: Nephrolithiasis; Urolithiasis; Idiopathic Hypercalciuria; Vitamin D Deficiency; Disorder of Vitamin D
MeSH terms: Urolithiasis; Nephrolithiasis; Kidney Calculi; Vitamin D Deficiency; Hypercalciuria
Intervention: Ergocalciferol
Intervention description: Ergocalciferol 50,000 IU's orally per week, for 8 weeks
Intervention MeSH terms: Vitamin D; Ergocalciferols
Phase: Phase 4
Study type: Interventional
Primary purpose: Treatment
Intervention model: Single Group Assignment
Masking: None (Open Label)
Enrollment: 30.0
Sex: All
Minimum age: 18 Years
Healthy volunteers: No
Keywords: Vitamin D insufficiency

Summary:

      Vitamin D plays a critical role in maintaining bone health, as well as preventing
      cardiovascular disease, cancer, and various autoimmune diseases, such as diabetes. Vitamin D
      deficiency is very common in the United States and worldwide, and is now being increasingly
      recognized and treated. One group in which vitamin D deficiency may be particularly important
      is patients who have had kidney stones. These patients frequently have elevated levels of
      calcium in their urine, which is a common and important risk factor for calcium containing
      kidney stones. Because vitamin D increases absorption of calcium into the blood by the
      intestines, physicians may be reluctant to prescribe vitamin D therapy to patients with
      vitamin D deficiency if they also have kidney stones and high amounts of calcium in the
      urine. They are concerned about the possible risk of increasing the amount of calcium in the
      urine (and thereby increasing the risk of calcium stones occurring again). However, studies
      in patients without kidney stones, as well as studies in patients with high calcium levels in
      the urine, have demonstrated that giving vitamin D is effective and safe and does not
      increase calcium in the urine. Therefore, the investigators will study the effects of giving
      vitamin D on the amount of calcium in the urine in patients with a history of kidney stones
      and elevated calcium in the urine. The investigators will evaluate the safety of giving
      vitamin D to this particular group of patients.
    

Eligibility criteria:

        Inclusion Criteria:

          -  History of nephrolithiasis as per medical record

          -  Urinary calcium excretion between 150 and 400 mg/day (measured within 3 months of
             study enrollment)

          -  25(OH)D deficiency or insufficiency (defined as a serum level < 30 ng/ml) within 3
             months of enrollment

        Exclusion Criteria:

          -  Pregnant women, since the optimal dose of vitamin D supplementation in this population
             has not been rigorously studied.

          -  Known uric acid, cystine, or struvite stone disease (because our intervention is
             predominantly aimed at patients with calcium stone disease). An exception to this is
             patients who have passed both uric acid and calcium stones, or patients who have
             passed stones of mixed composition (uric acid and calcium).

          -  Hypercalcemia (serum calcium > 10.4 mg/dL) at baseline

          -  Acute stone event or gross hematuria (blood in the urine) within the past 2 months

          -  Recent stone intervention within the past 1 month

          -  Suspected or known secondary causes of hypercalciuria, such as primary
             hyperparathyroidism, sarcoidosis, hyperthyroidism, or malignancy (except nonmelanoma
             skin cancer)

          -  Addition or dose change of medicines potentially affecting urinary calcium since the
             baseline 24hour urine collection (including diuretics, magnesium supplements,
             potassium supplements, potassium citrate, and vitamin D supplementation)