知っておきたい炎症性腸疾患の直腸肛門病変

The Perianal Disease Complicated with IBD

要旨●炎症性腸疾患（IBD）に合併する直腸肛門病変はその特徴的形態から疾患の診断に有用である．またQOLに大きな影響を及ぼすことも多く，その診断治療は，IBDを扱ううえで重要である．Crohn病（CD）に伴う肛門病変の治療は，一次病変はCD病変そのもののため内科治療を，二次病変は外科治療（切開，seton法など）の後，内科治療の強化を行う．潰瘍性大腸炎（UC）に合併する肛門病変では通常の肛門治療を行う．近年CD肛門病変の癌化例が増加しているが，予後が極めて悪いものの，有効なサーベイランス法が確立されていない．肛門部は容易に観察できる消化管で，診察法に慣れれば内科医でも簡単に診察できる．まず，肛門を見ることに慣れ，症状，形態の変化に早めに気づくことが重要である．

　The perianal disease complicated with IBD（inflammatory bowel disease）has a pathognomonic appearance, which indicates the precise diagnosis. Because the perianal disease induces negative effect on a patient's quality of life, the precise diagnosis and appropriate treatment of the perianal disease are critical in the clinical practice for IBD patients. In perianal CD（Crohn's disease）, the primary lesion is treated with medication and the secondary lesion is treated by surgery, such as incisional or set-on drainage, and intensification of medication after drainage. In case of ulcerative colitis, perianal disease patient is treated identically as that for non-IBD patients. Recently, the numbers of patients with neoplasia associated with perianal CD have increased and show poor prognosis. Despite the prevalence of these cases, there is no effective surveillance method yet established for the same. Anal lesion is a gastrointestinal tract lesion that can be observed easily. Thus, it is critical to include examination of the anal lesions in routine to detect change in symptoms and the formation of anal lesion at the earliest possible.