That was me, just asking if your husband was taking any medications. Some medications can cause an elevation in liver enzymes, even acetaminophen (tylenol) can have this effect in some people especially if it is used every day.
There are so many causes of elevated liver enzymes. If the elevation is mild, it could be a temporary problem that will reverse itself without treatment, and does not mean anything serious is going on. If the elevation is more than mild, and has been a problem for some time, there is probably some underlying health issue. It looks like his doctors are trying to determine the cause. And you mentioned that he is seeing a specialist---so I'm sure they will get to the root of the problem.
Here is a link for more information. There is a list of things that can cause elevated liver enzymes and you can click on each one for a description. But please do not get overly concerned yet, until you know what is going on for sure.
Elevated Liver Enzymes
There is a listed side effect, though rare, of liver problems with Lisinopril. You might want to talk to his doctor about this. He might be able to try another drug to see if it has some effect. Make sure to talk to the doctor about this first, do not let him stop taking the drug suddenly.