[The significance of "slight proteinuria"].

It is reported on renal biopsies in 67 patients with "slight proteinuria", 39 of whom were at an age of younger than 20 years. In 53 patients the cause of the "slight proteinuria" is a mesangio-proliferative glomerulonephritis, where in 2 cases severe changes with sclerosis were proved. Thus by way of addition the necessity of a renal biopsy is emphasized for the clarification of the cause also of a "slight proteinuria".