Early pathologic features of hereditary nephritis: a clinicopathologic correlation.

The histologic, immunofluoresence and electron microscopic features of renal biopsies from twelve patients having hereditary nephritis were examined and correlated with the clinical data. In ten patients with normal renal function, light microscopy showed similar but nonspecific glomerular abnormalities consisting of mild focal and segmental hypercellularity and thickening of capillary walls. Biopsies from two patients with azotemia had diffuse lesions of the glomeruli and associated interstitial fibrosis. There were no characteristic findings on immunofluorescence. Electron microscopy revealed alterations in thickness and density of the glomerular capillary basal lamina in all patients. However, lamellation of the basement membrane and the presence of electron dense granules were present only in the two patients with renal functional impairment. These findings support the view that hereditary nephritis is a form of glomerular disease in which ultrastructural changes in the basal lamina of glomerula capillaries are the earliest and most consistent lesions. However, the morphologic spectrum of these ultrastructural abnormalities is broader than previously recognized.