Presentation and outcome of gastrointestinal involvement in systemic necrotizing vasculitides: analysis of 62 patients with polyarteritis nodosa, microscopic polyangiitis, Wegener granulomatosis, Churg-Strauss syndrome, or rheumatoid arthritis-associated vasculitis - Pagnoux,C.; Mahr,A.; Cohen,P.; Guillevin,L. (Medicine (Baltimore), 2005)