An association between inflammatory bowel disease and enteroarthritis and the spondyloarthropathies has been known of for a while. Within the past few years, ileocolonic studies have expanded the diagnostic accuracy of asymptomatic gut inflammation, and it now seems evident that chronic gut inflammation is either associated with or is even the cause of chronicity of peripheral arthritis and the development of ankylosing spondylitis. This situation, previously studied in adult patients, now appears also to affect pediatric patients with spondyloarthropathies, who seem to have similar genetic and inflammatory bowel findings. Chronic infection in the gut has been demonstrated in Whipple's disease. Analogously, infection or immunologic aberrations probably contribute to chronicity in other forms of spondyloarthropathy. Infection also might be involved, at least partly in attacks of uveitis, but activation of immunologic mechanisms can mediate tissue destruction during eye inflammation.