[Liver disorders in adults: ALT and AST]

Area of Science:

• Clinical Biochemistry
• Hepatology
• Internal Medicine

Background:

• Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) are key serum biomarkers for assessing liver health.
• While ALT is primarily found in the liver, AST is also present in cardiac muscle, skeletal muscle, and erythrocytes, making ALT a more specific indicator of liver damage.

Observation:

• This report details two distinct cases of patients presenting with persistently elevated ALT and AST levels.
• The first case involved a 79-year-old woman with elevated transaminases post-myocardial infarction.
• The second case featured an obese 40-year-old woman with elevated transaminases without apparent symptoms, whose father died of liver cirrhosis.

Findings:

• The cases underscore the necessity of a thorough differential diagnostic approach when encountering elevated serum transaminase levels.
• The presence of AST in non-hepatic tissues complicates the interpretation of AST elevations.
• ALT remains the more specific biomarker for liver injury.

Implications:

• Understanding the differential diagnosis of elevated liver enzymes is crucial for accurate patient management.
• This review emphasizes the importance of considering various etiological factors beyond primary liver disease when interpreting ALT and AST levels.
• Further investigation into the diagnostic work-up, monitoring, and analytical considerations for these biomarkers is warranted.