Distribution and degradation of albumin in extensive skin disease.

The distribution and degradation of albumin were determined in twelve patients with extensive skin disease and in ten control subjects by measuring the metabolic turnover and transcapillary escape of 132 I-labelled albumin. The ratio of intravascular to total mass of albumin was normal. Thus the observed hypoalbuminaemia and the low intravascular mass reflect a reduced mass of total body albumin. The rate of synthesis was normal, but the transcapillary escape rate reflecting the microvascular leakiness to macromolecules, and the fractional disappearance rate were significantly higher in the patients than in the controls (P less than 0.001). It is concluded that the hypoalbuminaemia in these patients is the result of an increased endogenous catabolism of albumin without significant loss via urine, stools or skin. A positive correlation between the transcapillary escape rate and fractional catabolic rate of albumin supports the concept of a causal relationship between these parameters.