Acute fatty liver of pregnancy

• Overview:

  • Rare condition that occurs in the third trimester of pregnancy
  • Rapid accumulation of fat within the hepatocytes, causing acute hepatitis
  • High risk of liver failure and mortality, for both the mother and fetus
• Pathophysiology:

  • Impaired processing of fatty acids in the placenta
  • Result of a genetic condition in the fetus that impairs fatty acid metabolism
  • Most common cause is long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency in the fetus, which is an autosomal recessive condition. 
  • The fetus and placenta are unable to break down fatty acids - enter maternal circulation and accumulate in the liver
  • Leads to inflammation and liver failure
• The presentation is with vague symptoms associated with hepatitis :

  • General malaise and fatigue
  • Nausea and vomiting
  • Jaundice
  • Abdominal pain
  • Anorexia (lack of appetite)
  • Ascites
• Liver function tests will show elevated liver enzymes (ALT and AST).

  Other bloods may be deranged, with:

  • Raised bilirubin
  • Raised WBC count
  • Deranged clotting (raised prothrombin time and INR)
  • Low platelets
• HELLP syndrome also causes elevated liver enzymes and low platelets, but is more common than acute fatty liver of pregnancy - HELLP syndrome will have features of severe pre-eclampsia e.g. hypertension, oedema, hyperreflexia and clonus
• Management:

  • Obstetric emergency that requires prompt admission and delivery of the baby
  • Most patients will recover after delivery
  • Management also involves treatment of acute liver failure if it occurs - including consideration of liver transplant