Welcome! It's great that you are already seeing a hepatologist. The way you should see your medication is that the benefit far outweighs the risks they have. Immunosuppressants generally increase risk for certain cancers after very long term use...but they are only increased risks not guarantees that you'll develop them. On the flip side, the mortality rate with untreated AIH (especially severe as yours is with already having cirrhosis) is 5 years. Treated AIH generally has the same life span as the average Joe/Jane. Your docs are probably not concerned with your cirrhosis because there is still probably a lot of healthy liver left. So getting your AIH under control will keep what is still viable, viable. The liver is the only regenerating organ so what is still good can be all you need and what is only inflamed and not cirrhotic, can heal. You want to keep your own liver for as long as possible and not worry about another until absolutely necessary. A transplant doesn't mean you won't have AIH anymore as it isn't your liver that is ill, it's your immune system that is confused.
There's a girl, whose mom I've chatted with, she was diagnosed when she was 10. She hardly had any viable cells left and the docs wanted to transplant her right away. Mom said no as she wanted her to keep her own liver as long as possible. 6 years later, her liver is regenerating from the few cells that were there and she's a perfectly normal (takes quite a few meds though) teenager.
I, too, have AIH. When initially diagnosed I was on high pred and CellCept. Since I need to be on immunosuppressnats indefinitely (severe onset so trying not to risk a flare as those are harder to get into remission), I was switched to Imuran as it has long term data and CellCept is a newer drug. I didn't have any porblems on the CellCept at the time. I am fine on the Imuran so for now it's what I take. Currently, I am only on Imuran (100mg). Last year I started having some cholestasis from it but refused to decrease dose for fear of a flare so now I take Urso as well and all my numbers are normal.
Your fatigue can totally be because of your AIH. It is a side effect of the disease as is joint pain.
Make sure you don't start your pred wean until your numbers are normal. They should wean you quickly at first (I dropped 10 mgs every month). When I got to 7.5mg I stayed there for a few months then went to 5mg. I stayed on 5 mg for 11 months. The wean off the 5 mg is the slowest as your adrenal glands need to time start working again. That wean was 2 months. I was diagnosed in Jan 2007. My pred stopped Dec 2008 and so far so good.
Good luck and keep us posted on how you are feeling!
Diagnosed with AIH January 2007,
CMV (cytomegalovirus) June 2008
Raynaud's February 2010
meds: Azathioprine 100mg, Ursodiol 250mg BID