Approach to evaluating elevated liver tests in pregnant patients without acute liver failure

AFLP: acute fatty liver of pregnancy; HELLP: hemolysis, elevated liver enzymes, low platelet count; BMI: body mass index; NAFLD: nonalcohol-associated fatty liver disease; DILI: drug-induced liver injury; CMV: cytomegalovirus; EBV: Epstein-Barr virus; HAV: hepatitis A virus; HBV: hepatitis B virus; HBsAg: hepatitis B surface antigen; anti-HBc: antibody to hepatitis B core antigen; anti-HBs: antibody to hepatitis B surface antigen; HCV: hepatitis C virus; HEV: hepatitis E virus; HSV: herpes simplex virus; ANA: antinuclear antibody; MRCP: magnetic resonance cholangiopancreatography; ALT: alanine aminotransferase; AST: aspartate aminotransferase; IgM: immunoglobulin M; IgG: immunoglobulin G.
* Liver biochemical and function tests that are commonly measured include:

• Serum aminotransferases: ALT and AST
• Alkaline phosphatase
• Total bilirubin
• Prothrombin time/international normalized ratio

¶ Acute liver failure is characterized by severe liver injury (ie, serum aminotransferases typically more than 10 times the upper limit of normal, encephalopathy, and coagulopathy). Pregnant patients with acute liver failure require urgent consultation with maternal-fetal medicine and hepatology specialists and referral to a liver transplantation center.
Δ History includes risk factors for liver disease (eg, medications, alcohol), symptoms of liver disease (eg, jaundice, itching), and gestational age.
◊ For patients with suspected vascular disorders (eg, right upper quadrant pain, ascites), we also obtain doppler study to exclude vascular thrombosis.
§ A cholestatic pattern is a disproportionate elevation in the alkaline phosphatase compared with ALT and AST. Hepatocellular pattern of liver injury is a disproportionate elevation in ALT and AST compared with alkaline phosphatase.
¥ In regions where HEV is endemic, testing for IgM anti-hepatitis E virus is performed.