Alanine aminotransferase (ALT) is an enzyme primarily found in the liver, playing a crucial role in amino acid metabolism and the conversion of alanine to pyruvate. Elevated ALT levels are significant in clinical practice as they indicate liver cell injury, commonly associated with conditions like hepatitis, fatty liver disease, or drug-induced liver damage. Monitoring ALT is essential for diagnosing and managing liver disorders, guiding treatment decisions, and assessing liver function.