Extraintestinal Manifestations of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) mainly affects the gastrointestinal system but is associated with various chronic diseases of other organs that are jointly called extraintestinal manifestations (EIM). In some of these disorders, onset and clinical manifestations are associated with the course of the intestinal disease while in others they are independent of the intestinal disease. The former include peripheral arthritis, erythema nodosum or aphthous ulcers and episcleritis; the latter are pyoderma gangrenosum, uveitis, spondylarthropathy and primary sclerosing cholangitis (PSC). Other extradigestive-associated diseases are represented by gallstones and nephrolithiasis. Non-disease-specific complications such as amyloidosis, osteoporosis and thromboembolic complications are also common [1] (Table 1). EIM are more common when the colon is inflamed, i.e. in patients with Crohn’s disease (CD) of the colon rather than small bowel involvement. EIM can involve many organs, such as the skin, joints, eyes, liver/biliary system and kidney. They significantly influence morbidity and mortality of bowel disease, so their treatment is of major importance in the course of the intestinal disease [2].