Split and extremely thin glomerular basement membranes in hereditary nephropathy (Alport's syndrome).

Abstract

Alterations of the glomerular basement membrane are the earliest ultrastructurally demonstrable lesions in the course of hereditary nephropathy. The basement membranes may be either focally or diffusely thickened. They may be (a) homogeneously broadened, (b) show a typically split lamina densa, or (c) show a focally or diffusely thinned lamina densa layer. The latter may be one third or one half of the normal thickness. These findings provide further evidence for the hypothesis of basement membrane alterations as the basic lesion in hereditary nephritis.