Characterization of lymphoid follicles with red ring signs as first manifestation of early Crohn's disease by confocal laser endomicroscopy

Background and aims: Clinical observations suggest that the lymphoid follicles (LFs) may play a crucial role in the pathogenesis of inflammatory bowel disease (IBD), especially in Crohn's disease (CD), being sites of initial mucosal inflammation. The aim of this study was to compare the morphology of LFs in CD, ulcerative colitis (UC) and control patients using confocal laser endomicroscopy (CLE) in correlation to histological and immunohistochemical findings of targeted LFs biopsies. Methods: 146 patients (46 patients in CD group, 32 in ulcerative colitis (UC) group, 1 patient with indeterminate colitis; 72 mal…