Urinary osmolarity in late stage nephritis and nephrosis.

Urinary osmolarity was studied with the DDAVP test in 30 children in the late stage of glomerulonephritis or nephrosis syndrome, and in 12 control children. A restriction of the concentrating ability of the kidney was demonstrated in the cases accompanied by residual symptoms, in comparison to the healthy children and to the patients in lasting remission. In the cases examined histologically, tubular damage corresponding to the functional change could be demonstrated.