Diaphragm disease and stricturing Crohn’s disease: a clinicopathological study of overlapping and distinguishing features

Diaphragm disease is a rare cause of stricturing small bowel, associated with NSAID use, and may be unrecognized or misdiagnosed as Crohn’s disease. We compared histological features of diaphragm disease and stricturing Crohn’s disease, focusing on the submucosa and vascular structures.<br/><br/>Five diaphragm disease cases from were compared with five stricturing Crohn’s disease controls. Demographic and histological data were analysed.<br/><br/>Diaphragm disease was not clinically suspected in any case. One case had no documented NSAID use. Notable histological features included perpendicular submucosal connective tissue fibres, superficial ulceration and scattered inflammation. In contrast, Crohn’s disease strictures were associated with severe inflammation, lymphoid aggregates, deep ulceration and granulomas. Shared features included submucosal fibromuscular expansion and neuromuscular and vascular hamartomatous-like changes. Vascular injury was not seen.<br/><br/>Whilst the diagnosis of diaphragm disease remains challenging, these results shed light on features which support a diagnosis of diaphragm disease and those which<br/>are non-specific.