What does it mean when alanine aminotransferase levels are elevated?

Alanine aminotransferase (ALT) is a marker of liver function. Elevated ALT levels may be caused by various conditions, including hepatitis, cirrhosis, viral infections, alcoholic liver disease, liver injury, and liver cancer. In addition, certain medications, such as antibiotics and anti-tuberculosis drugs, can also lead to increased ALT levels. When elevated ALT is detected, prompt medical evaluation is recommended.