Plasma factor X_a-inhibitory activity in alcoholic liver disease and the effect of heparin

Factor X_a-inhibitor (X_a-I) activity was measured in twenty patients with alcoholic liver disease and found to be more than 3 standard deviations below normal in fourteen patients. When trace amounts of heparin were added to these plasmas, the X_a-I activity was potentiated to the same level as normal plasma with heparin added. This suggests that X_a-I is actually present in alcoholic liver disease, but has less than normal activity. Possible explanations such as the lack of endogenous heparin or the presence of an inhibitor are discussed.