Increased urinary nitrite excretion in children with minimal change nephrotic syndrome.

Abstract

We tested the hypothesis that nitric oxide synthesis by the kidney is increased in children with primary nephrotic syndrome. We examined the urinary excretion of nitrite, a stable metabolite of nitric oxide, using the Griess reaction, in children with nephrotic syndrome. In comparison with healthy children, patients with minimal change nephrotic syndrome had increased urinary nitrite excretion regardless of whether the disease was in relapse or remission (p < 0.025). In contrast, urinary nitrite excretion was similar in control subjects and patients with focal segmental glomerulosclerosis or IgA nephropathy. These findings indicate that measurement of urinary nitrite excretion may be a useful test to help discriminate between minimal change nephrotic syndrome and focal segmental glomerulosclerosis in children with idiopathic nephrotic syndrome.