Types of renal disease associated with Gout
• Urate nephropathy: deposition of MSU crystals in renal interstitial tissue with a surrounding giant cell reaction; may cause low-grade, intermittent proteinuria but only rarely causes significant renal dysfunction.
• Uric acid nephropathy: precipitation of uric acid crystals in the collecting ducts and ureters results in acute renal failure, as in the acute tumor lysis syndrome; characteristically occurs following chemotherapy for lymphoma or leukemia.
• Uric acid nephrolithiasis: occurs in up to10% to 25% of gout patients; risk parallels increases in serum and urinary urate concentrations as well as urine acidity. In contrast to calcium stones, uric acid stones are radiolucent. The incidence of calcium stones is also increased in patients with gout, particularly in those with hyperuricosuria, as uric acid serves as a nidus for calcium stone formation.
• Other: autosomal dominant medullary cystic kidney disease (one-third of patients have gout), lead intoxication (saturnine gout), and familial juvenile hyperuricemic nephropathy (an inherited uromodulin defect).
