Patients with HPS and colitis who are 18 years of age or older may be eligible for this study. Participants receive treatment for their colitis symptoms with one or more of several study drugs, which include mesalamine (5-ASA), corticosteroids, infliximab and 6-mercaptopurine, adalimumab and tacrolimus. The drugs are added to the treatment plan one at a time to find the combination that works best for the individual patient. Patients who respond to one or more of the medications may continue treatment with that same combination for up to 6 months.