My son is 5 months post a bmt for ipex syndrome. in the last 3 weeks his atl liver enzymes have risen to over 500! would would be causing this?

Many possibilities..: Elevated liver enzymes can be caused by a variety of things in the post transplant setting. Infections (such as viruses), medications, and gvhd (graft versus host disease) are among the more common. It sometimes can be difficult to figure out the cause (sometime we never do). Close monitoring is key. I hope your son gets better soon.