The case is reported of a 50 year old man with longstanding seronegative rheumatoid arthritis who developed ulcerative colitis. The patient also had sacroiliitis and his tissue was typed as HLA-A2-B27 several years before the bowel disease began. A possible overlap between primary inflammatory bowel disease, complications to the treatment of rheumatoid arthritis with drugs, and gastrointestinal rheumatoid vasculitis is discussed.