Nephrocalcinosis seen in all except: March 2005

Ans. B: Acute pancreatitis Primary hyperparathyroidism is single most common cause of nephrocalcinosis in adults Distal Renal Tubular Acidosis is second most common cause of medullary nephrocalcinosis - Both familial and secondary forms have high incidence - Contributing mechanisms are hypercalcemia, acidosis, and reduced excretion of citrate in the presence of increased urinary pH - Renal function is fairly well maintained Other causes of nephrocalcinosis are - Hypervitaminosis D due to treatment of hypoparathyroidism or self-administration of vitamins - Milk-alkali syndrome due to ingestion of milk or alkali for ulcer dyspepsia Sarcoidosis due to increased conversion of 25-hydroxycholecalciferol to 1,25-dihydroxycholecalciferol within the sarcoid granuloma - In children with hypophosphatemic rickets, nephrocalcinosis is increasingly being recognized as most common complication - Idiopathic hypercalciuria, one of the common metabolic diseases, also is known cause of nephrocalcinosis - Medullary sponge kidney is a common cause of medullary calcification in which calcium lies in ectatic collecting ducts rather than renal substance - Renal papillary necrosis associated with phenacetin-induced analgesic nephropathy is identified as calcified papillae rather than speckled pattern. - Rapidly progressive osteoporosis due to immobilization, menopause, senility, or steroids also may cause nephrocalcinosis - Hyperoxaluria, primary (familial) or secondary to increased intake of oxalates, enhanced absorption due to intestinal disease, or ingestion of ethylene glycol or methoxyflurane can induce medullary calcification