What is the real function of the liver 'function' tests?

Liver enzymes are commonly used in the evaluation of patients with a range of diseases. Classically they are used to give information on whether a patient's primary disorder is hepatitic or cholestatic in origin. However, knowledge of enzyme ratios and pattern recognition allow much more information to be derived from these simple tests. This paper offers an insight to generalists on how to extractgreater information from these tests in order to improve theinvestigation and management of liver disease.