There's lots you can do to combat warts...but since yours are internal, normal treatments like Aldara or other HPV topical treatments may be ineffective. The best thing to do would be to schedule an appointment with a proctologist and request for cryo, laser, or leep therapy to remove them. After that, you'll need to have annual anal pap smears to ensure that the cells in your anus do not undergo dysplasia...thus putting you at risk for anal cancer.
Hey, there's a Living with HIV forum, and the users there I think are the best people to answer your question :)