Nephrocalcinosis

Introduction

Nephrocalcinosis is characterized by deposition of calcium in the kidney tissue. Usually this occurs in medullary interstitial areas of the kidney. The condition is often associated with kidney stones calcareous (calcium phosphate or calcium oxalate). Otherwise can nephrocalcinosis cause acute or chronic renal failure or be randomly discovered by X-ray examination. Nephrocalcinosis may have different causes, and renal prognosis is determined by the underlying cause.

Causes

Nephrocalcinosis due to increased excretion of calcium salts in urine (calcium phosphate or calcium oxalate). In medullary areas where the osmolality is high and the concentration of salts exceeds the saturation solubility. Citrate is a natural inhibitor of the precipitation of calcium salts and hypocitraturi may contribute to the condition.

Table of common causes of nephrocalcinosis

Causes Examples
Hypercalciuria with hypercalcemia Primary hyperparathyroidism
Sarcoidosis
Hypervitaminosis D
Hypercalciuria without hypercalcaemia Distal renal tubular acidosis
Medulær sponge kidney
Loop diuretics
Congenital tubulopathy
Chronic hypokalemia
Hyperfosfaturi
Hyperoxaluria Congenital: primary
Acquired: fat malabsorption (short bowel syndrome)

Causes	Examples
Hypercalciuria with hypercalcemia	Primary hyperparathyroidism
	Sarcoidosis
	Hypervitaminosis D
Hypercalciuria without hypercalcaemia	Distal renal tubular acidosis
	Medulær sponge kidney
	Loop diuretics
	Congenital tubulopathy
	Chronic hypokalemia
Hyperfosfaturi
Hyperoxaluria	Congenital: primary
	Acquired: fat malabsorption (short bowel syndrome)

Histopathology

Heating, intracellular and interstitial calcium deposition. Interstitial inflammation, interstitial fibrosis and tubular atrophy could be a consequence of lime impact. (Picture Helge)

Urinary Findings

Hematuria may occur with concurrent kidney stones. Otherwise urinary findings usually sparse without proteinuria.

Course and treatment