Last Monday when I had Remus at the vet (the day he got diagnosed with insulinoma) I had them do a full blood screen. The vet called back today and said that his ALT liver enzymes were "a bit" elevated. He didn't sound too concerned so I brushed it off and said that I would come in next Monday for a BG check and we could talk then, but now I'm looking into it and found it that elevated ALT is indicative of liver damage... Can anyone give me some advice and sources to look through before I take him back on Thursday?
If he said not to worry I would try not to worry until you know more. I find that when they say "a bit" they often (though not always) just mean "a Bit," as in barely. Do you have any old lab values for Remus to compare to? Some individuals run naturally high or low, which is why getting blood work done while they are healthy is super important so you have a baseline to compare to. Often values that are just slightly elevated or decreased are not necessarily significant enough to be indicators of anything bad. Granted I do not know your vet or his ferret knowledge, but if he said not to worry I wouldn't work yourself up about it just yet. It's likely that they are only slightly elevated.
Additionally you should keep in mind that Pred can be hard on the liver, which may account for the elevated numbers (important Q: is he on prednisolone or prednisone? You want to make sure it's prednisolone as that's easier on the liver). Also, pancreatic inflammation can cause elevated liver values - and insulinoma is cancer of the pancreas.
Oh yes I forgot to add - muscle damage can also cause elevated values which I was once told by a vet can even in Some animals show up in super mild trauma such as rough play (you know ferrets), restraint, etc.
The blood was taken before he started on prednisolone. After looking up a bit more info I'm thinking it may just be because he had blood taken a couple days after a hypoglycemic episode? Because of the relation of pancreatic function to liver function. Either way, I'm probably going to make an appointment for Thursday afternoon or Friday morning.
If you planned to go in on Monday to check BG, then do that and simply tell the vet what you just told us. You've looked into it and now you're concerned and wondering what may have caused elevated levels. If the vet didn't sound concerned, you probably have nothing to worry about. His job is health, and if Remus was unhealthy, I'm sure this would've been brought up in a less passive manner. Let us know how the visit goes!