[High incidence of unexplained hypoalbuminemia in an internal medicine practice]

The frequent observation of hypoalbuminemia in patients without hepatic disease or renal protein loss led us to compare different methods of direct and indirect serum albumin measurement. One hundred patients were randomly selected and analysed retrospectively and the serum albumin was related to clinical, hematological and biochemical parameters. 51Cr labeled albumin was injected intravenously in 6 healthy volunteers and 8 patients with hypoalbuminemia to obtain further information on the pathogenesis of hypoalbuminemia. The results obtained by the method using bromcresol purple were almost identical with those obtained by immunological methods. On the other hand, serum electrophoresis gave results that were a mean 14% higher than those with the method using bromcresol purple. Nearly half of the patients selected randomly, generally without signs of liver disease or renal protein loss, were hypoalbuminemic. There was no correlation with the age, sex, blood sedimentation rate, serum orosomucoid, hemoglobin, aminotransferase or the prothrombin time. 51Cr labeled albumin showed normal disappearance in four patients and an accelerated disappearance in another four patients. Hypoalbuminemia is a common finding in internal medicine which is underestimated in incidence and extent when serum electrophoresis is used. There is no correlation with the age and the hematological or chemical parameters measured. Both reduced synthesis and/or increased loss or catabolism are important factors in the pathogenesis of hypoalbuminemia.