Water Excretion in Nephrotic Syndrome. Relationship Between Blood Volume and Plasma Vasopressin

In order to verify whether or not an increased secretion of ADH may cause the water retention commonly observed in nephrotic syndrome, 12 nephrotic patients and 11 normal subjects were studied in basal conditions and following a water load or iso-osmotic blood volume expansion. A significant direct correlation was observed between plasma ADH and Posm in controls but not in nephrotics. Plasma ADH was inversely correlated with BV in nephrotics but not in controls. Blood volume expansion in nephrotic patients was effective in reducing plasma ADH and promoting a water diuresis. These results demonstrate a sustained volume mediated secretion of ADH in nephrotic syndrome, which is responsible for the impairment in water excretion.