From the Guidelines
The workup for elevated liver enzymes in pregnancy, specifically Alanine Transaminase (ALT) and Aspartate Transaminase (AST), should begin with a thorough history and physical examination, followed by laboratory testing to determine the cause, including a complete liver function panel, bile acid levels, and hepatitis serologies, as recommended by the most recent guidelines 1. The initial assessment should include a complete liver function panel (AST, ALT, alkaline phosphatase, bilirubin, albumin), complete blood count, coagulation studies (PT/INR), and hepatitis serologies.
- Additional tests to consider include:
- Bile acid levels to diagnose intrahepatic cholestasis of pregnancy (ICP)
- Autoimmune markers (ANA, anti-smooth muscle antibody) to evaluate for autoimmune hepatitis
- Right upper quadrant ultrasound to evaluate for gallbladder disease or fatty liver The timing of enzyme elevation is important, as first trimester elevations may suggest viral hepatitis or hyperemesis gravidarum, while third trimester elevations could indicate preeclampsia, HELLP syndrome, or acute fatty liver of pregnancy.
- For mild elevations (less than 2-3 times normal) without symptoms, monitoring may be appropriate, with repeat testing every 2-3 weeks until 32-40 weeks' gestation, and then at least weekly until delivery, as recommended by the European Association for the Study of the Liver guidelines 1.
- For moderate to severe elevations, especially with symptoms like right upper quadrant pain, nausea, vomiting, or pruritus, prompt evaluation is necessary, including consideration of pregnancy-specific liver disorders like ICP, which may require treatment with ursodeoxycholic acid 10-15 mg/kg/day, as recommended by the American Gastroenterological Association 1. The workup should distinguish between pregnancy-specific conditions (which may require delivery for definitive treatment) and coincidental liver disease, with consultation with both maternal-fetal medicine and hepatology specialists recommended for persistent or severe elevations to ensure appropriate management for both mother and fetus 1.
From the Research
Diagnostic Approach to Elevated Liver Enzymes in Pregnancy
The workup for elevated liver enzymes, specifically Alanine Transaminase (ALT) and Aspartate Transaminase (AST), in pregnancy involves a comprehensive diagnostic approach to distinguish between pregnancy-specific liver diseases and non-pregnancy-related liver damage 2, 3.
Pregnancy-Specific Liver Diseases
Pregnancy-specific liver diseases include:
- Intrahepatic cholestasis of pregnancy (ICP), characterized by pruritus and elevated bile acid levels, with increased risk of preterm birth, meconium-stained amniotic fluid, and stillbirth 4
- Hemolysis, elevated liver enzyme, low platelet (HELLP) syndrome, a severe complication of pre-eclampsia 5
- Acute fatty liver of pregnancy, a rare but life-threatening condition requiring urgent delivery 5
Non-Pregnancy-Related Liver Damage
Non-pregnancy-related liver damage includes:
- Pre-existing liver diseases, such as non-alcoholic fatty liver disease (NAFLD), which can progress to hepatocellular carcinoma and is associated with increased risk of pregnancy complications and abnormal fetal growth 6
- Coincidental liver damage, such as viral hepatitis or drug-induced liver injury
Diagnostic Workup
The diagnostic workup for elevated liver enzymes in pregnancy should consider both pregnancy-specific and non-pregnancy-related liver diseases, and may include:
- Liver function tests, such as ALT, AST, and bile acid levels
- Imaging studies, such as ultrasound or MRI
- Laboratory tests, such as complete blood count and coagulation studies
- Medical history and physical examination to identify risk factors and symptoms of liver disease
Management and Treatment
Management and treatment of elevated liver enzymes in pregnancy depend on the underlying cause and may involve:
- Ursodeoxycholic acid treatment for ICP to improve maternal symptoms and biochemical tests 4
- Urgent delivery for pregnancy-specific liver diseases, such as acute fatty liver of pregnancy or HELLP syndrome 5
- Management of pre-existing liver diseases, such as NAFLD, to reduce the risk of pregnancy complications and abnormal fetal growth 6