Renal medullary nephrocalcinosis is the commonest form of nephrocalcinosis and refers to the deposition of calcium salts in the medulla of the kidney. Due to the concentrating effects of the loops of Henle, and the biochemical milieu of the medulla, compared to the cortex, it is 20 times more common than cortical nephrocalcinosis.
Often (and perhaps unsurprisingly) the same entities may also lead to nephrolithiasis (renal calculi).
Pathology
Causes include 1,2:
- medulla
- hyperparathyroidism
- medullary sponge kidney
- renal tubular acidosis (type 1)
- hypervitaminosis D
- milk-alkali syndrome
- sarcoidosis
- hyperthyroidism or hypothyroidism 5
- other pathological hypercalcemic or hypercalciuric states
- pyramids
- hyperuricemia
- infection (particularly renal tuberculosis)
- sickle cell disease (leading to infarction and subsequent dystrophic calcification)
- renal papillary necrosis
- drugs
- furosemide abuse 4