What biochemical marker is most commonly elevated in patients with liver disease?

Alanine aminotransferase (ALT) is the most commonly elevated biochemical marker in patients with liver disease because it is an enzyme that is primarily found in the liver. When liver cells are damaged, ALT is released into the bloodstream, leading to elevated levels. This makes it a sensitive marker for liver injury, often used in the diagnosis and monitoring of various liver conditions, such as hepatitis, fatty liver disease, and liver cirrhosis.

Elevated ALT levels indicate hepatocellular damage, which is a common feature in many types of liver diseases. While alkaline phosphatase may be elevated in cases involving bile duct obstruction or cholestasis, it is not as specific for liver cell injury as ALT. Creatinine levels relate more closely to kidney function rather than liver disease, and while bilirubin can be elevated in liver diseases, it is typically a later finding and indicates complications such as bile duct obstruction or liver failure rather than initial hepatocyte damage. Therefore, ALT serves as a primary marker for early detection and evaluation of liver health.