What results in increased liver values?

There are several types of parameters that are measured to assess the liver. The values most often referred to are the liver enzymes ALT and ALP as well as bile acids.

Liver enzymes are found within the liver cells. If the liver is damaged these enzymes leak out of the cells, resulting in higher levels found in the blood.

    - The liver enzyme ALT is quite specific to the liver; that is, if a dog has an increased amount of ALT     it is likely due to liver damage.

   - :ALP however, is less specific to the liver; it is found in other parts of the body (such as the skeleton). For instance, an increase in ALP is also seen in digestive problems, Cushings disease and young, growing, dogs.

Liver enzymes help indicate liver damage, but do not provide information regarding liver function. To gain information regarding liver function bile acids need to be measured. Increased levels of bile acids in the blood indicate the liver is unable to function properly.

It can be difficult to find the cause behind increased liver enzymes because the liver is easily affected by other body systems. Substantial increases in liver enzymes are often associated with direct trauma/damage to the liver (such as tumours). Inflammation of the mouth, conditions affecting the digestive tract, as well as certain hormonal diseases can also result in increased liver values. Therefore an extensive diagnostic work up is often required to identify the underlying cause.