What is the management approach for elevated Liver Function Tests (LFTs) in pregnancy?

Management of Elevated Liver Function Tests in Pregnancy

When elevated liver function tests (LFTs) are detected in pregnancy, prompt identification of the underlying cause and appropriate management are essential to reduce maternal and fetal morbidity and mortality.

Differential Diagnosis of Elevated LFTs in Pregnancy

Pregnancy-Specific Liver Disorders:

• Intrahepatic Cholestasis of Pregnancy (ICP)

  • Characterized by pruritus and elevated bile acids (>10 μmol/L) 1
  • May present with elevated transaminases and bilirubin 1
  • Increased risk of adverse fetal outcomes including stillbirth, especially with bile acids >100 μmol/L 1

• HELLP Syndrome (Hemolysis, Elevated Liver Enzymes, Low Platelets)

  • Often associated with pre-eclampsia 1
  • Characterized by hemolysis, elevated liver enzymes, and thrombocytopenia 1
  • Risk of hepatic hemorrhage or hematoma, especially with platelet count <20×10⁹/L 1

• Acute Fatty Liver of Pregnancy (AFLP)

  • Rare but potentially fatal condition 1
  • Usually presents in third trimester with nausea, vomiting, abdominal pain, and jaundice 1
  • May progress rapidly to liver failure 2

• Hyperemesis Gravidarum

  • Elevated LFTs in 40-50% of severe cases 1
  • Usually mild and self-limiting 1

Pre-existing or Coincidental Liver Disease:

• Non-alcoholic Fatty Liver Disease (NAFLD)

  • Found in 16-18% of pregnant women 3
  • Associated with obesity, diabetes, and metabolic syndrome 3
  • Increased risk of pregnancy complications 3

• Viral Hepatitis, Autoimmune Hepatitis, Drug-Induced Liver Injury

  • May present or exacerbate during pregnancy 4

Diagnostic Approach

1. Initial Assessment:

   • Measure serum bile acids, transaminases (ALT/AST), bilirubin, alkaline phosphatase, GGT, and platelets 1
   • Evaluate for symptoms of liver disease (pruritus, right upper quadrant pain, jaundice) 1

2. Further Evaluation Based on Clinical Presentation:

   • If pruritus is present: Test for serum bile acids to identify ICP 1
   • If hypertension is present: Consider pre-eclampsia and HELLP syndrome 1
   • If severe symptoms with jaundice: Consider AFLP and evaluate using Swansea criteria 1
   • If hyperemesis with elevated LFTs: Screen for primary liver disease if markedly elevated 1

3. Imaging:

   • Abdominal ultrasound for women with severe pre-eclampsia or HELLP syndrome with symptoms suggestive of hepatic hematoma 1
   • Ultrasound is safe at any gestation in pregnancy 1

Management Strategies

Intrahepatic Cholestasis of Pregnancy (ICP):

• Monitor serum bile acids at least weekly from 32 weeks' gestation 1
• Ursodeoxycholic acid (UDCA) should be offered for:
  • Treatment of maternal pruritus 1
  • Reduction of spontaneous preterm birth risk in women with bile acids >40 μmol/L 1
• Delivery planning:
  • For bile acids >100 μmol/L: Recommend delivery from 35 weeks' gestation due to increased stillbirth risk 1
  • For bile acids >40 μmol/L but <100 μmol/L: Consider induction by 39 weeks' gestation 1

HELLP Syndrome:

• Prompt delivery once maternal coagulopathy and severe hypertension have been corrected 1
• Treat severe hypertension urgently with antihypertensive therapy 1
• Administer magnesium sulfate to prevent eclamptic seizures 1
• Corticosteroids for fetal lung maturity if delivery before 35 weeks' gestation 1
• Early referral to a transplant center if signs of hepatic failure 1

Acute Fatty Liver of Pregnancy (AFLP):

• Intensive care admission for women who develop encephalopathy, elevated serum lactate (>2.8 mg/dl), MELD score >30, or Swansea criteria score >7 1
• Expedite delivery once coagulopathy and metabolic derangements have been treated 1
• Consider plasma exchange post-delivery for severe hepatic impairment 1
• N-acetylcysteine may be considered for women in intensive care 1
• Early referral to a transplant center for severe hepatic impairment 1

Hyperemesis Gravidarum:

• Monitor LFTs as they are elevated in 40-50% of severe cases 1
• Screen for primary liver disease if markedly raised LFTs 1

Special Considerations

• Multidisciplinary approach: Management by a team including hepatologists, obstetricians, and midwives with expertise in liver diseases of pregnancy 1

• Post-delivery monitoring:

  • Ensure normalization of LFTs within 3 months post-delivery 1
  • If LFTs remain abnormal, investigate for underlying liver disease 1

• Genetic screening for women with ICP if there is a family history of hepatobiliary disease, early onset, or severe disease 1

Common Pitfalls to Avoid

• Dismissing mildly elevated LFTs which may indicate serious underlying conditions 5
• Failing to measure serum bile acids in women with pruritus 1
• Delaying delivery in women with HELLP syndrome or AFLP 1
• Not recognizing NAFLD as a common cause of abnormal LFTs in pregnancy 3
• Missing the distinction between pregnancy-related and coincidental liver disease 2