Reduced serum levels of immunoreactive erythropoietin in patients with cirrhosis and chronic anemia.

Chronic anemia is frequently observed in patients affected by cirrhosis. To investigate the possible role of erythropoietin (Epo) in the pathogenesis of anemia in cirrhosis, we measured the immunoreactive Epo levels and the respective hemoglobin (Hb) concentrations in 48 anemic and nonanemic cirrhotic patients and in a control group of healthy subjects and patients with iron-deficiency anemia. Epo concentrations were determined in serum using a sensitive enzyme immunoassay. The regression curve between Epo values and Hb concentrations showed a significant inverse exponential trend both in cirrhotic patients (r = -.55; P < .0001) and controls (r = -.92; P < .0001). In a semilogarithmic plot, the line slope obtained in cirrhotic patients was significantly lower (P < .005) than that of controls, suggesting a blunt Epo response to anemia in cirrhosis. Moreover, covariance analysis showed that the Epo levels for a given degree of anemia were further reduced in the patients with a more severe disease, suggesting a close relation between cirrhosis and the mechanisms involved in the derangement of the Epo feedback system. Finally, the Epo concentrations measured in the cirrhotic patients without anemia did not significantly differ from Epo values obtained in healthy subjects. An impaired Epo response may play a role in maintaining low Hb concentrations in cirrhotic patients with anemia. However, the evidence of a residual Epo response to anemia in cirrhosis and the presence of normal basal Epo levels in nonanemic cirrhotic patients do not support an inadequate Epo secretion as one of the primary causes of anemia in cirrhosis.