Definition of Nephrocalcinosis:

Nephrocalcinosis is a kidney disorder in which there is an increased amount of calcium in the kidneys.

Causes, incidence, and risk factors:

Nephrocalcinosis may be caused by a number of conditions:

• Excess excretion of calcium by the kidney
• Renal tubular acidosis
• Medullary sponge kidney
• Hypercalcemia (high calcium levels in the blood)
• Renal cortical necrosis
• Tuberculosis

Pieces of of calcium oxalate or calcium phosphate may break free from the kidney. The pieces (deposits) enter the kidney tubules and areas in between them. The deposits may result in reduced kidney function. Pieces of calcium may lead to the formation of stones (nephrolithiasis).

This condition is relatively common in premature infants, partly from intrinsic kidney calcium losses and partly from enhanced calcium excretion when they are given loop diuretics.