虚血性大腸炎の臨床像

Clinical Features of Ischemic Colitis

要旨　筆者らは，虚血性大腸炎の本質は腸管側因子であることを種々の観点から検討し，報告してきた．本稿では，虚血性大腸炎の臨床像について筆者らの考えを中心に述べ，文献的考察を加えた．特に，内視鏡診断については詳しく述べた．筆者らは，虚血性大腸炎急性期の内視鏡像を血管拡張，うろこ模様，偽膜様所見，チアノーゼ所見の4つに分類した．虚血性大腸炎急性期の内視鏡像はこれらの所見で構成されており，内視鏡所見を客観的に表記することが可能である．主病変が縦走性の偽膜様所見とその周囲のうろこ模様から成り，周辺にうろこ模様や血管拡張から成る横走性病変，あるいは斑状病変などの小病変がみられるのが典型的内視鏡像である．また，それぞれに対応する組織像を比較した結果，組織学的に虚血の程度はこの順に重篤となり，この内視鏡分類の妥当性が証明された．この分類を用いると，観察時に組織像や重症度もある程度推測可能である．また，虚血性直腸炎と虚血性右側結腸炎についても自験例について述べ，文献的考察を加えた．

　We have reported from several points of view that the intestinal factors play an essential role in the pathogenesis of ischemic colitis. We give our opinion with clinical features of ischemic colitis and review of the literature.

　Endoscopic findings in the acute stage of ischemic colitis were classified qualitatively into four groups ; scale-pattern, pseudomembranelike appearance and cyanotic appearance. These results suggested that the most typical endoscopic feature of ischemic colitis in its acute stage, which was the major lesion showing longitudinal pseudomembranelike appearance and surrounding scale-patterns, accompanied by minor lesions such as transverse lesions or macular lesions composed of scale-pattern or vasodilation. We could describe endoscopic findings objectively by our endoscopic classification. When these qualitative endoscopic features were compared with pathological findings, the severity of ischemia evaluated pathologically increased in the order of vasodilation, scale-pattern, pseudomembranelike appearance, and cyanotic appearance. We could speculate some extent severity and pathological finding of ischemic colitis by our endoscopic classification

　We also described our cases of ischemic proctitis and ischemic right-sided colitis, and review of the literature.