炎症性腸疾患の腸管外合併症

Extraintestinal Manifestation of Inflammatory Bowel Disease

要旨●潰瘍性大腸炎（UC）とCrohn病（CD）に代表される炎症性腸疾患（IBD）はさまざまな合併症を生じることがあり，発症部位により“腸管合併症”と“腸管外合併症”に分類する．腸管合併症には，腸管の狭窄や瘻孔，消化管癌などがあり，腸管外合併症には，関節，皮膚，肝胆膵，腎尿路，血管，眼などの全身臓器に多彩な病変が認められる．具体的には，関節の脊椎関節炎，皮膚の結節性紅斑，壊疽性膿皮症，帯状疱疹などが高頻度に認められ，自己免疫性膵炎や原発性硬化性胆管炎，腎尿路結石，血管炎，ぶどう膜炎なども認める．一方で病勢に伴い発症する血栓塞栓症はIBDの病勢よりも重篤となることがあり注意を要する．

　Inflammatory bowel disease（IBD）such as ulcerative colitis and Crohn's disease cause various complications, which are classified as “intestinal manifestations” and “extraintestinal manifestations” depending on the site of onset. Intestinal stenosis, fistula, and gastrointestinal cancers are examples of intestinal manifestations while lesions in systemic organs such as joints, skin, hepatobiliary pancreas, renal urinary tract, blood vessels, and eyes are the extraintestinal manifestations. Specifically, spondyloarthritis, erythema nodosum, pyoderma gangrenosum, herpes zoster, autoimmune pancreatitis, primary sclerosing cholangitis, renal urinary tract stones, vasculitis, and uveitis are the frequent extraintestinal manifestations. On the other hand, thromboembolism, which develops with the progression of the disease, can be more severe than IBD and requires prompt attention.