AST still elevated

About 6 weeks ago my AST began being somewhat elevated. It was mentioned to me before surgery but it was hoped to be caused by some other medication I was on (Avonex) and I was taken off of it. It's still high though. It's now at 139. The doctor mentioned I may need to get my G.I. tract looked through.

Does anyone know what a likely cause of this would be? I've done a lot of research online and on Wikipedia but it's been really hard to sort through all the stuff. I'm really nervous about this as all the causes basically sound pretty bad.

I've had NO problems though. I feel healthy, have had no digestive problems aside from the normal lapband liquid and mushy diet side effects . I don't drink alcohol and my only prescription I'm currently on is hydrochlorothiazide for blood pressure and it is controlling it great.

In two weeks I get my liver function levels tested yet again to decide if I need to have that done. I'm 23/m and I'm pretty scared about this. I'm healing great from lapband surgery I had on oct 15 but now this has come up. I've lost about 25 pounds since the beginning of the pre-op diet and am feeling good.

I wish I could hurry up and found out if there is a problem or not and what it could be!