The different forms of glomerulonephritis morphological and clinical aspects, analyzed in 2500 patients.
Comparative morphological and clinical studies of 2,500 patients suffering from glomerulonephritis, enabled us to divide the different forms of diffuse glomerulonephritis into 3 distinct groups and to separate these groups from the focal glomerulonephritides. The different forms of diffuse glomerulonephritis in group I are: 1. endocapillary (acute) glomeruloenphritis (of the post-streptococcal type), 2. mesangioproliferative glomerulonephritis, 3. mesangioproliferative glomerulonephritis with focal crescents, 4. mesangioproliferative glomerulonephritis with focal scarring, 5. minimal proliferating intercapillary glomerulonephritis without nephrotic syndrome. It is emphasised that these forms can transform into one another, that they seldom occur with nephrotic syndrome, and with varying frequency with hypertension. Group II consists of: 1. minimal proliferating intercapillary glomerulonephritis with nephrotic syndrome, 2. focal sclerosing glomerulonephritis, 3. perimembranous glomerulonephritis, 4. membranoproliferative glomerulonephritis, 5. lobular glomerulonephritis. It is stressed that these glomerulonephritis forms usually do not develop out of group I type glomerulonephritis forms, and that in this group a nephrotic syndrome is the most prominent clinical syndrome. In the third group are 1. mesangioproliferative glomerulonephritis with diffuse crescents, 2. necrotising glomerulonephritis. It is shown that this form of glomerulonephritis does not usually develop from either group I of II forms. The fourth group of focal glomerulonephritis is uncommon. This disease is characterized by a necrotising and proliferative inflammatory lesion found segmentally and focally in the glomeruli. Most of the other glomeruli appearing normal. It is emphasised that in the literature the diagnosis focal glomerulonephritis is made far too often. This is because glomeruli in which the inflammatory process in a few lobules is of varying prominence, are included in the focal glomerulonephritis group. The classification of the different forms of glomerulonephritis into 3 groups here described, is thought of as a basic classification. It is compared with Ellis' classification (1942), with which it has much in common.