What To Do When Your Dog Or Cat's Liver Tests Are High
Ron Hines DVM PhD
The blood test results most indicative of a potential liver problem in your pet are elevations in its ALT, AST, GGT, and ALP enzyme levels. Its not that unusual for one or more of these tests to be a bit high; but for your dog or cat to appears healthy. Those moderate elevations are often found in “wellness” checkups or suggested yearly health exams.
The first thing you need to understand is that although we associate these enzymes with the liver, there are many non-liver health issues that will also cause these enzyme levels to rise. Things like pancreatitis, infections (like lepto), gall bladder disease (bacterial cholangitis) , portosystemic shunts, intestinal disease or failing heart. Medications (like corticosteroids) anti-seizure medications (ref) or NSAIDs, like Rimadyl® , that your pet might be taking can also be responsible. So can herbal supplements. (ref) My approach is to retest these pets in 4-6 weeks. Many times, the second round of tests will be normal.
If its still abnormal, a bile acid test is in order. If the bile acids test is high, veterinarians often place pets on a trial course of antibiotics and usually throw in some “liver support” products like Denamarin® or Denosyl®. They might even suggest a prescription diet such as l/d® Liver Care with the suggestion to repeat the blood test in 4-7 weeks. There is certainly no harm in giving those unproven products.
If the elevation is still there, your veterinarian needs to determine if the underlying issue is some non-liver problem or if the problem is indeed in your dog or cat’s liver. Symptoms like jaundice (icterus, yellowish skin), fluid buildup in the tummy (ascites), a mass or lump felt in the liver or seen on x-rays or any changes in the pet’s mental state (ie hepatic encephalopathy) make a primary liver problem more likely. If no non-liver problem could be found, most vets would then recommend x-rays and ultrasound examination of the pet’s abdomen. If those exams were not sufficient to make the diagnosis, most vets would suggest that a fine, long needle be entered, under anesthesia, through the pet’s body wall and into its liver and a tiny plug of liver tissue removed. That tissue would be sent to a pathologist to determine what abnormalities were present at a cellular level (fine needle aspirate).