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 ones 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. Prognosis
The prognosis of nephrocalcinosis is determined by the underlying cause. Most cases of nephrocalcinosis do not progress to end stage renal disease, however if not treated it can lead to renal dysfunction this includes primary hyperoxaluria, hypomagnesemic hypercalciuric nephrocalcinosis and Dents disease. Once nephrocalcinosis is found, it is unlikely to be reversed, however, partial reversal has been reported in patients who have had successful treatment of hypercalciuria and  hyperoxaluria following corrective intestinal surgery. Recent research
In recent findings they have found that there is a genetic predisposition to nephrocalciosis, however the specific genetic and epigenetic factors are not clear. There seems to be multiple genetic factors that regulate the excretion of the different urinary risk factors. There has been some correlation seen that shows gene polymorphisms related to stone formation for calcium-sensing receptor and vitamin D receptors.
nephrogenic diabetes insipidus) as can be seen in hypercalcemia, medullary nephrocalcinosis of any cause, or in children with Bartter syndrome in whom essential tubular salt reabsorption is compromised.There are several causes of nephrocalcinosis that are typically acute and present only with kidney failure. These include tumor lysis syndrome, acute phosphate nephropathy, and occasional cases of enteric hyperoxaluria. Cause
Nephrocalcinosis is connected with conditions that cause hypercalcemia, hyperphosphatemia, and the increased excretion of calcium, phosphate, and/or oxalate in the urine. A high urine pH can lead to  Nephrocalcinosis but only if it is accompanied by hypercalciuria and hypocitraturia, since having a normal urinary citrate usually inhibits the crystallization of calcium. In conjunction with Nephrocalcinosis, hypercalcemia and hypercalciuria the following can occur:
Primary hyperparathyroidism: Nephrocalcinosis is one of the most common symptoms of primary hyperparathyroidism. Sarcoidosis: Nephrocalcinosis is one of the most common symptoms. Vitamin D: This can cause nephrocalcinosis because of Vitamin D therapy because it increases the absorption of ingested calcium and bone resorption, resulting in hypercalcemia and hypercalciuria. Medullary nephrocalcinosis
Medullary sponge kidney
Distal renal tubular acidosis
Hyperoxaluria
Renal papillary necrosisAnd other causes of hypercalcemia (and thus hypercalciuria)
Immobilization (leading to hypercalcemia and hypercalciuria)
Milk-alkali syndrome
Hypervitaminosis D
Multiple myeloma

Hypercalciuria without hypercalcemia
These conditions can cause nephrocalcinosis in association with hypercalciuria without hypercalcemia:
Distal renal tubular acidosis
Medullary sponge kidney
Neonatal nephrocalcinosis and loop diuretics
Inherited tubulopathies
Chronic hypokalemia
Beta thalassemia

Mechanism
Nephrocalcinosis is caused by an increase in the urinary excretion of calcium, phosphate, and/or oxalate. Nephrocalcinosis is closely associated with nephrolithiasis, and patients frequently present with both conditions, however there have been cases where one occurs without the other.