What causes elevated liver enzymes in dogs?

Original Question: Annual blood test has revealed that ALP has risen from 150 (last year) to 270 (last week). Should I be concerned? My dog seems to be doing well. Also she had another rabies (3 year) and I discovered when reviewing past vaccinations she had a rabies vaccination last year when she was not supposed to receive one until this year. What problems do over vaccinations cause? I just discovered a small lump on her thigh. Could that be the result of other vaccinations she also received last week? - Marie

Sep 18, 2018

Hi Marie,

Thanks for your question.

ALP is a liver enzyme that we can assess on blood work. Whenever we see an elevated ALP in dogs on blood work, it is important that you don’t evaluate it in isolation. It needs to be interpreted as part of the bigger picture. We can see ALP elevate with particular conditions, Cushing’s disease would certainly be the most common, and less likely are conditions of the liver such as liver disease, liver cancer, infectious conditions of the liver, and general hepatitis. It’s important to know that in most cases of liver damage, another enzyme is often elevated called ALT. An elevated ALT in dogs is much more indicative of liver cell damage and is the more concerning enzyme of the two.

It is also common for ALP to be elevated for benign reasons and it’s common to see it elevated in dog’s that are older. I have seen elevations on routine wellness testing of very healthy dogs on a frequent basis and I often cannot find any condition causing it. I have known it to be elevated in dogs that are anxious as well which is a situation that mimics overactive adrenal glands, which is what occurs in Cushing’s disease.

In dogs that are older and do have elevated ALP levels, we often see it slowly rise every year. The vast majority of cases are not due to disease states. However, many vets will recommend testing to determine whether there is a condition present that is responsible for it. They will often perform a test for Cushing’s disease and a liver function test for liver impairment. They may also recommend imaging the liver with X-rays (radiographs) or ultrasonography. It’s ideal to look for a source of the anomaly but keep in mind that blood levels can differ in individual dogs and they don’t need to fall into the range of the masses. It’s important to judge the significance of a blood abnormality in conjunction with symptoms that are present or any other signs that make your veterinarian or yourself suspect that there could be an ailment present. There is an adage in veterinary medicine that goes: ‘treat the dog, not the data’. This means you can’t get hung up on one abnormality and address it alone, you need to consider the overall health of the patient to better understand whether it is a genuine concern.