Crohn病における小腸粘膜治癒評価の意義—バルーン内視鏡の立場から

Significance of the Evaluation of Small Intestinal Mucosal Healing in Crohn's Disease：A Study from the Standpoint of Balloon Assisted Enteroscopy

要旨●Crohn病（CD）の予後改善のため内視鏡的治癒が提案されている．その中でバルーン内視鏡（BAE）は小腸病変を直接に観察でき，予後予測にも有用であるが，侵襲性もあり他のモダリティの併用も重要である．これまでのCDの内視鏡評価は大腸評価が中心であったが，小腸のスコアリングとして近年mSES-CDが提案されている．臨床的血清学的寛解例でも半数弱の例で小腸病変を伴い，これらは再燃の高危険群であることが判明した．一方，完全な粘膜治癒でなくとも縦走潰瘍がなければ良好な予後が期待できる．また，潰瘍を伴わない狭窄に対する内視鏡的拡張術の予後は潰瘍を伴う例よりもよいため，狭窄部の内視鏡的治癒は治療目標となりうる．

　Endoscopic healing has been proposed to improve the prognosis of CD（Crohn's disease）. BAE（balloon assisted enteroscopy）can directly approach small intestinal lesions, and BAE is useful not only for the current evaluation processes but also for CD prognosis prediction ; however, this intervention is also invasive. When such intrusive procedures become difficult to conduct, selective imaging with a water-soluble contrast medium or other modalities can be employed instead. Moreover, previous studies have focused on the use of endoscopic evaluation for scoring CD prognosis and assessing colonic lesions, whereas mSES-CD has been proposed for small intestine examinations. We found that Less than half of the patients experiencing clinical and serological remission have significant small bowel lesions, which places them at a high-risk for relapse. Nevertheless, even if complete mucosal healing is unachieved, an advantageous prognosis can be expected in the absence of longitudinal ulcers. As a result, the healing of patients diagnosed with longitudinal ulcers is proposed to be a therapeutic target that prevents clinical relapse. Additionally, the prognosis of endoscopic balloon dilation for stenosis without ulceration is better than that of stenosis with ulceration. Hence, endoscopic healing of stenosis is a therapeutic target.