A 42-year-old man is admitted with bleeding from esophageal varices. Investigation reveals that he has an occlusion of the portal vein. There is no evidence of liver cirrhosis. Which test will most likely reveal an underlying predisposing factor for this condition?
Hepatitis screening Iso-amylase Intravenous pyelogram to exclude hydronephrosis Coagulation tests to include antithrombin III