[Immunohistochemical findings in renal biopsies performed on diabetics (author's transl)]

Renal biopsies obtained from 22 patients with diabetes (8 women, mean age 38.5 years; 14 men, mean age 27.3 years)--including patients with potential, latent, short-term, and long-term diabetes--were examined by light microscopy as well as by immunofluorescence microscopy. Histologically, segmental and focal proliferation of mesangial cells as well as a mesangial broadening and an increase of substance deposited in the mesangium was found. These findings well documented by cell counting an differentiation are described in detail elsewhere (see Sorger et al. 1976 Immunhistochemically, we detected most frequently IgA (9/17) and IgG(9/17), usually in a linear or mesangial pattern, less frequently IgM (1/17). We failed to detect beta 1C and IgE in the glomerulus. Labeled insulin was demonstrated 5 times. Out of the plasmaproteins albumin, fibrinogen, transferrin, and beta-lipoproteid only albumin was perceptable. We consider the deposition of immunglogulins and serum-proteins in the glomerular filter to be an unspecific stimulation of proliferation of the mesangial cells being caused by overfunction and obviously produce an excess of the mesangial matrix.