text: In some cases a renal biopsy is done instead if imaging is not enough to confirm nephrocalcinosis. Once the diagnosis is confirmed additional testing is needed to find the underlying cause because the underlying condition may require treatment for reasons independent of nephrocalcinosis. These additional tests will measure serum, electrolytes, calcium, and phosphate, and the urine pH. If no underlying cause can be found then urine collection should be done for 24 hours and measurements of the excretion of calcium, phosphate, oxalate, citrate, and creatinine are looked at.
  Stages of nephrocalcinosis
  Chemical or Molecular nephrocalcinosis: Defined as a measurable increase in intracellular calcium concentrations, however, it is not visible through X-ray or microscopically.
  Microscopic nephrocalcinosis: Occurs when depositis are visible by light microscope by obtaining a tissue sample from a biopsy. However, this cannot be seen in an X-ray.
  Macroscopic nephrocalcinosis: Occurs when calcification can be seen through X-ray imaging.
  Treatment
  Increasing fluid intake to yield a urine output of greater than 2 liters a day can be advantageous for all patients with nephrocalcinosis. Patients with hypercalciuria can reduce calcium excretion by restricting animal protein, limiting sodium intake to less than 100 meq a day and being lax of potassium intake. If changing one's diet alone does not result in a suitable reduction of hypercalciuria, a thiazide diuretic can be administered in patients who do not have hypercalcemia. Citrate can increase the solubility of calcium in urine and limit the development of nephrocalcinosis. Citrate is not given to patients who have urine pH equal to or greater than 7.