The natural history of screening detected IgA glomerulonephritis in children.

The clinical course of 43 children with IgA glomerulonephritis detected by mass urine screening was followed for a mean period of 8.1 years. Histological findings were graded according to the severity of glomerular and tubulointerstitial lesions. There was no correlation in the severity of histological grade and clinical outcome between subjects with microscopic hematuria and those with microscopic hematuria and proteinuria nor between those with and without one or more episodes of macroscopic hematuria during the follow-up period. None of the 35 children with proteinuria less than or equal to 1 g/m2/day had severe histological findings or developed renal impairment. In contrast, the 8 children with proteinuria greater than 1 g/m2/day had moderate and severe histological findings. Four of these 8 children developed hypertension or renal insufficiency during the follow-up period. Our study indicates that the outcome of screening detected IgA glomerulonephritis in children correlates with the level of proteinuria and the severity of renal pathology.