Pylephlebitis, also known as ascending septic thrombophlebitis, is a thrombotic occlusion of the portal vein or its branches secondary to infection in regions that drain to the portal venous system.

Clinical presentation

Clinical presentation is often vague. Patients may initially present with non-specific abdominal pain, nausea and sepsis in the context of an intra-abdominal infection. Sequelae from hepatic involvement such as jaundice or hepatomegaly may occur in advanced stages. 

Pathology

Thrombosis of the portal circulation rapidly leads to bowel ischemia, necrosis and perforation. 

Etiology

• septic focus

  • diverticulitis is the most common cause

  • appendicitis

  • necrotizing pancreatitis

  • hepatic abscess

• hypercoagulative status

• trauma

• abdominal surgery

• hepatobiliary diseases: cirrhosis, hepatocellular carcinoma

Radiographic features

Ultrasound

Findings on color duplex sonography include flow defect and dilation or absent compressibility of the portal venous system ³.

CT

CT is the modality of choice as it may also detect an underlying cause as well as complications such as bowel ischemia or abscess formation. The finding of an endoluminal thrombus causing a filling defect in contrast filled mesenteric veins is diagnostic ³.

Treatment and prognosis

Complications of pylephlebitis include thrombus propagation into a mesenteric vein, hepatic abscess, hepatic and splenic infarctions and chronic thrombosis ⁴.

Medical management with antibiotics and anticoagulation is the mainstay of therapy. 

Mortality with early treatment remains as high as 25% ^2,4.

History and etymology

Pylephlebitis was initially described by Waller in 1954 as a cause of hepatic abscess found during autopsy ¹.