My dog has high liver enzymes but no symptoms. What should I do?

I assume when you say liver enzymes you mean ALT? There a few enzymes we look at and elevation in 1 value makes us consider different causes then elevation in another. ALT elevation is caused make liver cell injury and leakage of enzymes in to the bloodstream. As the liver sees all the blood of the body it can be quite a reactive organ. So the question is whether the liver enzyme is up because of something wrong with the liver/vessels to liver themselves (such as an infectious or inflammatory cause (hepatitis) or a shunt (more common in younger dogs)) or something the liver is responding too (toxicity, disease of over organs). Unfortunately all parts of sago palm are toxic to dogs with the seeds (nuts) being most toxic. And it can be quite challenging to know if this is the cause. If it is sago it depends on the degree of ingestion as to how severe the case is. Unfortunately the treatment for this is supportive as you have been doing. The values may continue to increase or hopefully may plateau off and remain mildly elevated or decrease again. Ultrasound will help to rule out other things going on in the abdomen, assess the liver for changes in texture (although a liver can appear normal on an ultrasound and not be functionally normal), and sometimes identify a portosystemic shunt. After the ultrasound then sampling either first by fine needle aspirate or with a biopsy (needed for many cases of hepatitis, some other issues) can be performed. Checking platelets and clotting times should be performed prior to liver sampling in patients whose livers are not normal to decrease the risk of bleeding from sampling. As shunts are more common in younger animals , if this is suspected, additional imaging may be recommended prior to sampling as ultrasound will not identify all shunts. There is also a disorder called microvascular dysplasia that can be found in the liver. This is best diagnosed by liver biopsy and the sample sent to a pathologist who specializes in liver pathology. I hope this has helped and not confused you more. It sounds like your vet has taken the appropriate steps thus far and has recommended the next best steps to try to rule out some other causes. Thank you for using Petco Pet Education Center, formerly Petcoach!