<prompt> Sudden abdominal pain in polycythemia vera is due toHepatic vein thrombosisHyperviscosityPancreatitisSmall bowel-obstruction  <response>: A Hepatic vein thrombosis 898-H 18th Intra abdominal venous thrombosis is particularly common in young women and may be catastrophic if a sudden and complete obstruction of the hepatic vein occurs 898- H 18th Thrombosis sometimes also occurs in the hepatic veins producing Budd- chiary syndrome and the porlal and mesenteric veins leading to bowel infarction 619- Robbins south- asian edition Intense pruritis and peptic ulceration may occurs both possibly resulting from the release of histamine from basophils 619- RobbinsHepatic vein thrombosis is associated with indecreasing order of frequency Polycythemia vera Pregnancy Post partum state Use of oral contraceptions Paroxysmal nocturnal hemoglobinuria PNH Hepatocellular carcinomaBudd chiarys syndrome - characerised by Hepatomegaly Weight gain Ascites Abdominal vein 