Cholestasis

Cholestasis refers to reduced or blocked flow of bile through the biliary tree, usually due to an obstruction. This causes bile components, including bile acids and bilirubin to be absorbed into the blood. It may cause jaundice if severe enough.

Cholestasis may be intrahepatic or extrahepatic, depending on the location of the problem.

Treatment depends on the underlying cause and is indicated as cholestasis predisposes to secondary infection (cholangitis) or liver disorder.

Etiology

• Extrahepatic cholestasis
  • Choledocholithiasis
  • Obstruction by malignancy (pancreatic, hepatobiliary)
  • Biliary stricture (as a postoperative complication or post-inflammation)
  • Parasites
• Intrahepatic cholestasis
  • Drug-induced cholestasis (antibiotics, antipsychotics)
  • Primary biliary cholangitis
  • Primary sclerosing cholangitis
  • Intrahepatic cholestasis of pregnancy
  • Liver disease

Clinical features

If cholestasis causes sufficient hyperbilirubinaemia, it may cause jaundice. Pruritus is also a symptom of cholestasis, which can be debilitating. The cause of the cholestasis may also cause symptoms, like biliary colic or symptoms of malignancy.

Diagnosis and evaluation

See also liver biochemical tests.

Laboratory evaluation can show signs of cholestasis, mostly the cholestatic parametres ALP and GGT. Alkaline phosphatase (ALP) is significantly elevated, more than three times the upper normal limit, but ALP can be elevated in bone disorders as well. Gamma-glutamyl transpeptidase (GGT) is also significantly elevated in cholestasis. If ALP and not GGT is elevated, a non-biliary cause is likely.

Hepatocellular markers like ALT and AST may also be elevated in cholestasis, but usually to a lesser degree than the cholestatic markers.

Conjugated hyperbilirubinaemia is a sign of cholestasis.

Imaging is indicated and may show the cause itself, but not necessarily. Dilated bile ducts is a sign of cholestasis. Ultrasound is usually the first choice, other options are MR cholangiopancreatography (MRCP), CT, or endoscopic ultrasound.

Treatment

Specific treatment depends on the underlying cause.

Cholestatic pruritus may be severe. Warm baths and antihistamines may help, but not always. The best treatment is the combination of a bile acid sequestrant (cholestyramine or colestipol) together with ursodeoxycholic acid (UDCA). Other options include rifampin, opioid antagonists, SSRIs, or phenobarbital.