Sinonasal involvement as a rare extraintestinal manifestation of Crohn's disease

Crohn's disease is a chronic idiopathic slowly developing transmural inflammation of the digestive system. It usually involves the small intestine and/or the area around the anus but can also affect the entire gastrointestinal tract anywhere from the mouth to the anus. Extra intestinal manifestations occur frequently and multiple organ systems may be affected: the skin, joints, spine, eyes, liver and bile ducts. In contrast, nasal manifestations are extremely rare and only a few cases have been reported up to date in the worldwide literature. The authors report two cases with nasal manifestations concomitant to intestinal Crohn's disease and go over the relevant literature on such an association.