[IgA nephropathy in diabetes mellitus (author's transl)]

Report on a diabetic patient with IgA nephropathy whose kidneys were examined by biopsy four times during a period of four years. Morphologically the typical findings were observed: Outstanding deposits of IgA, hypercellularity and increase of matrix within the mesangium. The findings persisted during the period of observation. The differential diagnosis between IgA nephropathy and a slight diffuse glomerulosclerosis in diabetes mellitus is discussed. IgA nephropathy is diagnosed with certainty only by the aid of immunohistology.