Aetiology

A third of cases are idiopathic. Recognised causes include:

• hypercoagulable states:
  • including polycythaemia vera
  • pregnancy
  • antiphospholipid syndrome
  • essential thrombocythaemia
  • protein S / protein C / antithrombin III deficiency
• myeloproliferative disease
• contraceptive pill
• posterior abdominal wall sarcomas
• renal and adrenal tumours
• hepatocellular carcinoma
• hepatic infections, such as hydatid disease
• trauma
• congenital venous webs - idiopathic membranous stenosis of inferior vena cava between hepatic veins and right atrium is often associated with hepatic venous thrombosis
• paroxysmal nocturnal haemoglobinuria
• radiotherapy