Albumin Metabolism and Gastrointestinal Loss of Protein in Chronic Renal Failure

Abstract

The catabolism of albumin labeled with 125I was studied in 10 patients with advanced renal failure and in 5 with nephrotic syndrome. In 10 patients the gastrointestinal [GI] protein loss was studied simultaneously by determining the fecal excretion during 7 days of 51Cr after i.v. administration of 51Cr-labelled CrCl2. The results were related to a control group in which 12 subjects were studied with respect to albumin catabolism and 17 with respect to the GI protein losses. In the 2 patient groups the mean for serum albumin concentration and the intravascular albumin pool, expressed as g or g/kg body weight, were significantly decreased compared with those of the control group. The 2 patient groups had an increased extravascular albumin pool and an elevated ratio between extra- and intravascular pools. The mean albumin catabolic rate was not increased in the renal insufficiency group, expressed as a percentage of the intravascular pool/24 h or as g/24 h. In the patients with nephrotic syndrome, it was significantly increased. The renal insufficiency group had a mean cumulative 51Cr excretion during 7 days of 1.6 .+-. 0.80% of the given dose, the control group 0.63 .+-. 0.30%. This difference was highly significant. The patients with nephrotic syndrome did not differ from the control group.