Development of ulcerative colitis in a patient with multiple sclerosis following treatment with interferon beta 1a

To alert clinicians to a potential novel adverse drug effect of interferon beta 1a, we herein report a patient with relapsing-remitting multiple sclerosis who developed ulcerative colitis following treatment with interferon beta 1a. Ulcerative colitis persisted despite discontinuation of interferon beta 1a treatment and switching the patient to glatiramer acetate. Tacrolimus (FK506), 6-mercaptopurine, and prednisolone were required to induce remission. Both ulcerative colitis and multiple sclerosis were eventually well controlled using this regimen. Our report underscores that caution should be exercised when prescribing immunostimulatory agents in patients with inflammatory bowel disease (IBD) and challenges current efforts to stimulate innate immunity as a novel therapeutic concept for IBD.