What laboratory parameter is most indicative of liver function?

Alanine aminotransferase (ALT) is considered one of the most sensitive indicators of liver function. This enzyme is primarily found in the liver, and its levels in the blood often increase in response to liver cell damage. When the liver is inflamed or injured, ALT is released into the bloodstream, making its measurement a valuable tool in assessing liver health.

In clinical practice, elevated ALT levels can signify various liver conditions, such as hepatitis or fatty liver disease. Monitoring this enzyme helps healthcare providers evaluate the degree of liver injury and assess ongoing liver function.

While alkaline phosphatase, creatinine, and bilirubin are important laboratory markers, they do not provide as clear a picture of liver function specifically. Alkaline phosphatase can indicate bile duct obstruction or certain bone disorders, creatinine is primarily a marker for kidney function, and bilirubin levels are more reflective of the liver's ability to conjugate and excrete bilirubin rather than overall liver function. Thus, ALT remains a key marker in the assessment of liver function.