Association between the subepidermal autoimmune blistering diseases linear IgA disease and the pemphigoid group and inflammatory bowel disease: two case reports and literature review.

We report two patients with subepidermal autoimmune blistering diseases and inflammatory bowel disease (IBD) [one with linear IgA disease (LAD) and ulcerative colitis (UC), and the other with mucous membrane pemphigoid (MMP) and Crohn disease (CD)], and present a review of all previously reported cases. We reviewed the literature, and found 48 cases of patients with autoimmune blistering diseases and IBD. The blistering diseases were LAD (25 patients), bullous pemphigoid (BP) (21), MMP (1) and pemphigoid gestationis (1), while the IBD types comprised UC (40) and CD (8). We describe the clinical and immunopathological features and demographic characteristics of the patients. In all but one case, the diagnosis of IBD predated the development of the skin condition. The association was more common with LAD than BP. The immunopathogenesis of IBD and autoimmune blistering diseases is discussed and a link between them hypothesized, namely, that the presentation of multiple antigens to the immune system during the unregulated inflammation in the bowel wall results in excitation of the immune system and recognition of autologous antigens.