9．炎症性腸疾患（CD・UC）との鑑別を要する腸管感染症

Enteric Infections that Need be Differentiated from Inflammatory Bowel Diseases (CD・UC)

要旨　IBD（UC，CD）と鑑別を要する感染性腸炎は慢性型（腸結核，アメーバ性大腸炎）と急性型（細菌性赤痢，キャンピロバクター腸炎，サルモネラ腸炎，病原性大腸菌腸炎，エルシニア腸炎）に分けられる．IBDとこれら腸炎との鑑別ポイントを下記に述べる．腸結核では輪状傾向の潰瘍，瘢痕萎縮帯所見，非乾酪性であっても大型で融合性の肉芽腫をどこかの部位に認める（CDとの鑑別）．アメーバ性大腸炎では潰瘍のたこいぼ様形状や介在粘膜の血管透見像をどこかの部位に認める（UCとの鑑別）．キャンピロバクター腸炎ではBauhin弁上の潰瘍を高率に認める（UCとの鑑別）．サルモネラ腸炎では直腸が健常の場合が多い（UCとの鑑別）．エルシニア腸炎では通常，縦走潰瘍の形成はない（CDとの鑑別）．腸管出血性大腸菌腸炎では腺管の融解や変性壊死を高率に認める（UCとの鑑別）．IBDと感染性腸炎の鑑別は，上述の肉眼形態像のみならず病歴，検査所見，血清学的検査，糞便・腸内容物・腸粘膜組織の病原体検査，臨床経過なども加味して行うことが重要である．

　Enteric Infections that need to be differentiated from IBD (CD･ UC) are divided into the chronic type (intestinal tuberculosis and amebic colitis) and the acute type (bacillary dysentery, Campylobactor enterocolitis, Salmonellosis, Entero-pathogenic Escherichia. coli enterocolitis, and Yersinia enterocolitis) . The essential points for differential diagnosis between IBD and enteric infection were as follows: Intestinal tuberculosis had annular-like ulcers, a scar-atrophic band like finding, and large confluent non-caseous granulomas somewhere in the lesions (differential points from CD). Amebic colitis had verrucose shaped ulcers and distinct vascular pattern on the interposed mucosa in somewhere (differential points from UC). Campylobactor enterocolitis might had an ulcer on the Bauhin's valve frequently (a differential point from UC). Salmonellosis might have normal rectum (a differential point from UC). Yersinia enterocolitis usually did not cause a longitudinal ulcer (a differential point from CD). Enteropathogenic Escherichia coli enterocolitis showed 1iquefaction of the duct and degenerative necrosis frequently (differential points from UC). To distinguish infectious enterocolitis from IBD, not only macroscopic findings of the colonoscopic examination, but medical history, lab data, serological examination, microbiological examination of the stool, intestinal contents and intestinal mucosa, and clinical course are important.