Jaundice

Jaundice refers to a clinical sign of hyperbilirubinemia (>2.5 mg/dl) which has many causes. It is often a clue to a diagnosis. It can be largely divided into two types:

• non-obstructive, i.e. pre-hepatic and hepatic causes
• obstructive, i.e. post-hepatic causes

Imaging has a major role in detecting the obstructive causes.

Clinical presentation

Jaundice is the yellowing of the skin and/or sclerasclerae. Patients may present with painless or painful jaundice. Painless jaundice is always very suspicious for an underlying obstructive malignant cause ³. 

Pathology

Categories of causes ³:

• prehepatic
  • haemolytic anaemia
  • mechanical heart valve
  • hypersplenism
• hepatic
  • acute hepatitis / acute liver failure
  • cirrhosis
  • Gilbert syndrome
• post-hepatic (a.k.a. obstructive jaundice)
  • benign causes
    • choledocholithiasis
    • strictures, e.g. post-inflammatory/infectious, primary sclerosing cholangitis
    • external biliary tree compression, e.g. pancreatic pseudocyst, Mirizzi syndrome
  • malignant causes
    • portal lymphadenopathy
    • cholangiocarcinoma
    • carcinoma of head of pancreas
    • hepatocellular carcinoma
    • gallbladder carcinoma

Radiographic features

Patients presenting with jaundice is a common indication for imaging. Often a specific cause will not be found, and the main role is differentiating between non-obstructive and obstructive jaundice. In the latter, extrahepatic and/or intrahepatic bile duct dilatation can be expected, depending on the level of obstruction. 

Hepatobiliary ultrasound and MRCP are the mainstay imaging modalities. Bilirubin levels are often too elevated for CT cholangiography to be performed.  

Treatment and prognosis

Management depends on the underlying aetiology. In jaundiced neonates, phototherapy and exchange transfusion should be considered.

Complications

• bilirubin-induced neurologic dysfunction (e.g. kernicterus) in unconjugated jaundice