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 of one or two enzymes are often picked up in “wellness” checkups or yearly health checkups your veterinarian suggests.

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 above normal averages. Things like pancreatitis, infections like leptospirosis, gall bladder disease (bacterial cholangitis), portosystemic shunts, intestinal disease or a 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) Transient unidentified processes not associated with organ disease can cause moderate, temporary elevations in these tests as well. So my approach is to retest these pets in 4-6 weeks. Many times, the second round of tests will be normal.

If tests are still abnormal, a bile acids test is probably 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 will want to determine if the pet’s underlying issue is some non-liver problem or if the problem is indeed in your dog or cat’s liver. Symptoms like jaundice (icterus or 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. While guided by ultrasound, into its liver a tiny plug of liver tissue (biopsy) would be collected. That tissue would be sent to a pathologist to determine what abnormalities were present at a cellular level. An alternative when an abnormal liver mass (lump) is detected might be a fine needle aspirate.

You are on the Vetspace animal health website