Final answer:
ALT being higher than AST typically indicates acute liver damage, with ALT being more liver-specific and thus a more sensitive marker.
Step-by-step explanation:
ALT being higher than AST suggests acute liver damage, such as that from viral hepatitis or an overdose of paracetamol (acetaminophen). Alanine aminotransferase (ALT), which catalyzes the transfer of an amino group from alanine to alpha-ketoglutarate, is more specific to the liver than aspartate aminotransferase (AST).
While both ALT and AST can be elevated in cases of liver damage, ALT is typically more elevated in acute liver injury scenarios. In contrast, AST is also present in red cells, and cardiac and skeletal muscles, making it less specific to the liver. However, the ratio of AST to ALT can help differentiate between causes of liver damage.
Additional enzymes like alkaline phosphatase (ALP) and gamma glutamyl transpeptidase (GGT) also play roles in diagnosing liver conditions. ALP levels rise in cases of large bile duct obstruction or liver infiltrative diseases, and GGT levels can indicate sub-clinical levels of liver dysfunction or alcohol toxicity.