Electron microscopic studies in hereditary nephritis.

A characteristic electron microscopic lesion-longitudinal splitting of the glomerular basement membranes with accumulation of dark particles-was found in some cases of hereditary nephritis, especially in Alport syndrome. A somewhat similar but less specific alteration was present in the tubular basement membranes and in the Bowman capsule. The lesions tended to exhibit a familial segregation. The possible pathogenesis of the lesions and their relation to physiologic abnormalities are briefly discussed.