Evidence for an erythropoietin-stimulating factor in patients with renal and hepatic disease.

Recently, a factor was discovered in the serum of hepatectomized animals which was capable of augmenting the hepatic erythropoietin response to hypoxia when injected into normal rats. This substance was localized in the liver via an in situ perfusion technique and was termed the hepatic erythropoietic factor (HEF). Patients with kidney disease, liver disease, and combined renal and hepatic disease were studied in this report. Detectable HEF levels were found in the plasma of patients with both liver and kidney disease and were highest in anephric patients with various liver diseases. However, HEF levels were negligible in normal humans or in patients manifesting renal disease with no hepatic involvement. The data suggest that HEF-induced hepatic erythropoietin synthesis may occur in humans as well as in animals.