Review of systems should seek extra-articular symptoms of causative disorders, including fever (infection, sometimes crystal-induced arthritis), urethritis (gonococcal arthritis or reactive arthritis), rash or eye redness (reactive arthritis, spondylitis, vasculitis, or psoriatic arthritis), history of abdominal pain and diarrhea (inflammatory bowel disease), and recent diarrhea or genital lesions (reactive arthritis).