portal vein thrombosis

Etiology

• hypercoagulable state
  • inherited
    • JAK2 V617F mutation (50%)
    • factor V Leiden mutation
    • prothrombin gene mutation (G20210)
    • antithrombin 3 deficiency
    • protein C deficiency
    • protein S deficiency
  • acquired
    • lupus anticoagulant
    • cirrhosis
    • disseminated intravascular coagulation (DIC)
    • burns
    • sepsis
    • malignancy
    • myeloproliferative disorders
    • pregnancy & postpartum state
    • oral contraceptives
    • inflammation
      • diverticulitis, inflammatory bowel disease, pancreatitis
    • stasis from reduced blood flow
    • splenectomy
    • ingestion of a foreign body (fish bone), with penetration of the duodenum, pancreas, & superior mesenteric vein (case report)
• not a consequence of the progression of cirrhosis

Pathology

• formation of a thrombus within the portal vein
  • thrombus can involve segments of the mesenteric veins or splenic vein
• portal hypertension
• diminished blood supply to the liver
• cavernous formation of the portal vein, which represents bridging collaterals around the occlusion

Clinical manifestations

• acute form
  • fever
  • abdominal pain if mesenteric vein extension

Laboratory

• D-dimer level may be elevated
• JAK2 V617F mutation

Diagnostic procedures

• abdominal ultrasound (doppler)

Radiology

• computed tomography (CT) with contrast
• magnetic resonance imaging (MRI)

Complications

• intestinal ischemia, infarction
• does not directly affect progression of cirrhosis
• predicts near-term appearance of liver cancer & pancreatic cancer with a poor prognosis

Management

• acute form (non-cirrhotic patients)
  • thrombolysis through the transhepatic route, avoids the need for systemic thrombolysis
    • tissue-type plasminogen activator (tPA)
    • follow with warfarin for at least 3 months (indefinitely inpatients with inherited coagulation disorders
    • rivaroxaban of benefit (rather than warfarin)
  • shunt surgery with subsequent anticoagulation is an alternative if intestinal infarction suspected
  • anticoagulation for at least 3 months
• chronic form
  • patient presenting with bleeding varices with imaging revealing cavernous transformation of the portal vein, denoting long-standing disease
  • anticoagulation is not advisable
    • anticoagulation may facilitate regression of thrombosis with recanalization & diminish cirrhosis progression without increasing bleeding risk in patients with cirrhosis
  • variceal banding or sclerotherapy, often requires several sessions to obliterate the bleeding
  • octreotide infusion has also been used in acute bleeding
  • propranolol is often used prevent rebleeding in the setting of portal vein thrombosis, but evidence base is lacking

More general terms

• splanchnic vein thrombosis (SVT)
• liver disease
• hypercoagulability

Additional terms

• portal vein