Granulomatous interstitial nephritis and uveitis presenting as salt-losing nephropathy.

Salt-wasting nephropathy is a rare syndrome in which renal insufficiency is associated with extracellular volume depletion from marked natriuresis in the absence of adrenal insufficiency or diuretics. We report the clinical course of a 23-year-old woman with renal insufficiency, in association with orthostatic hypotension and salt wasting. A combination of daily infusion of saline, a high-salt diet and oral fludrocortisone did not compensate for her salt loses. Renal biopsy showed noncaseating granulomas and marked interstitial inflammation. Renal function and salt loss improved with prednisone therapy and 6 months after withdrawal of steroids, her renal function remains stable.