Gastrointestinal single-organ vasculitis is a vasculitis restricted to one organ in the gastrointestinal system and without systemic manifestations. These diseases are rare and true incidence and prevalence are difficult to determine. Most patients will have predominantly gastrointestinal symptoms although some will be asymptomatic, and in these cases the diagnosis is incidental. The diagnosis typically relies on pathology and/or imaging studies. Systemic vasculitis must be excluded in all cases. Cases of limited single-organ vasculitis can sometimes be managed with surgery alone whereas cases of diffuse disease often require immunosuppressive therapy. The disease has been associated with significant morbidity and mortality, particularly in the first year after diagnosis. All cases should be monitored closely for the possible evolution to systemic vasculitis.