[Idiopathic interstitial nephritis induced acute renal failure: clinical and pathological analysis]

To understand idiopathic interstitial nephritis (IIN) and its relationship with acute renal failure as well as its clinical and pathological characteristics for avoiding misdiagnosis and missing diagnosis.

A detail clinical and pathological analysis was performed on 7 patients with idiopathic interstitial nephritis.

The major manifestations were acute non-oliguric renal insufficiency combined with mild proteinuria (< 2 g/d), microscopic hematuria and obvious disorder of renal tubular function (for example, glycosuria). Three patients had high gamma-globulinemia and 2 were associated with uveitis. Renal biopsy showed typical tubulointerstial nephritis but glomeruli, and the renal vasculature was almost normal. All patients were treated with prednison. Renal function recovered in 5 patients.

When a patient has renal insufficiency especially non-oliguric renal failure with disorder of tubular function without definite causes, IIN should be considered. The diagnosis and treatment should be done immediately.