What is the significance of elevated Aspartate Aminotransferase (AST) and Alanine Aminotransferase (ALT) levels, specifically AST 229 and ALT 106, indicating hepatocellular injury?

From the Guidelines

I strongly recommend immediate further evaluation for this patient with elevated liver enzymes (AST 229, ALT 106) to prevent progression to more severe liver disease, as indicated by the most recent study 1. The patient's elevated liver enzymes indicate moderate liver inflammation, with an AST:ALT ratio >2:1, which is concerning and suggests ongoing liver cell damage. This ratio can suggest alcoholic liver disease, muscle injury, or certain medication effects, as noted in the study 1.

Key Recommendations:

• The patient should temporarily discontinue any potentially hepatotoxic medications and avoid alcohol completely, as advised in the study 1.
• Immediate blood tests should include a complete liver panel (bilirubin, alkaline phosphatase, GGT, albumin), viral hepatitis serologies, autoimmune markers, and iron studies, as recommended in the study 1.
• Ultrasound of the liver is also recommended to assess for structural abnormalities, as suggested in the study 1.
• While waiting for results, the patient should stay well-hydrated and avoid acetaminophen and NSAIDs, as cautioned in the study 1.
• If symptoms like jaundice, severe abdominal pain, confusion, or dark urine develop, immediate medical attention is necessary, as emphasized in the study 1. The elevated AST:ALT ratio (>2:1) is concerning and suggests ongoing liver cell damage that requires prompt investigation to prevent progression to more severe liver disease, as highlighted in the study 1.

From the Research

AST and ALT Elevations

• Elevated serum levels of transaminases (AST and ALT) usually indicate hepatocellular damage 2
• ALT elevations can also be of extrahepatic origin, such as muscle injury 2, 3
• The ratio of AST to ALT in serum and the mitochondrial isoenzyme of AST can help differentiate between alcoholic and non-alcoholic liver diseases 2

Causes of Elevated AST and ALT

• Common causes of elevated AST and ALT include:
  • Alcoholic liver disease
  • Chronic viral hepatitis
  • Non-alcoholic steatohepatitis (NASH)
  • Chronic viral hepatitis
  • Drug-induced liver disease
  • Non-alcoholic steatosis 2, 4
• Non-hepatic causes of elevated AST and ALT include:
  • Polymyositis
  • Acute muscle injury
  • Acute myocardial infarction
  • Hypothyroidism 4

Evaluation of Abnormal Liver Chemistries

• The evaluation of hepatocellular injury includes testing for viral hepatitis, assessment for nonalcoholic fatty liver disease, and screening for hereditary hemochromatosis, autoimmune hepatitis, Wilson's disease, and alpha-1 antitrypsin deficiency 5
• A liver biopsy may be considered when serologic testing and imaging fails to elucidate a diagnosis, to stage a condition, or when multiple diagnoses are possible 5

Clinical Significance of AST and ALT Elevations

• Elevated AST and ALT levels have been associated with increased liver-related mortality 5
• The degree of elevation of ALT and/or AST can help guide the evaluation of abnormal liver chemistries 5
• A combined assessment of AST/ALT in conjunction with IL-2 at the early stages of symptomatic dengue virus infection may be useful to predict severe forms of dengue 6