潰瘍性大腸炎の内視鏡的重症度評価─NBI拡大内視鏡所見からみた重症度

Assessment of Disease Activity for Ulcerative Colitis Depends on Magnifying Endoscopic Findings Using Narrow Band Imaging

要旨●潰瘍性大腸炎（UC）の疾患活動性をNBI拡大内視鏡観察する場合，白色光観察に対して上乗せ効果が期待されるものとして，血管所見が挙げられる．高度な粘膜治癒が達成されたUC粘膜のNBI拡大内視鏡所見は，蜂巣状構造を呈する．寛解期UC粘膜のNBI拡大観察所見で，蜂巣状構造以外の所見を細分化して，予後との関連を検討した報告は乏しい．NBI拡大内視鏡観察は点の観察となるため，組織学的活動性との関連についての報告がみられる．しかし，UCは面の拡がりを病理学的特徴とする疾患であり，拡大内視鏡で観察した部位が，大腸全体の疾患活動性をどの程度担保するのかが課題となる．

　Magnifying endoscopic findings using NBI（narrow band imaging）for microvascular pattern provide additional information compared with conventional white-light observation to assess the disease activity in patients with UC（ulcerative colitis）. The appearance of honey-comb structure by magnifying NBI observation was found in the mucosa that achieved complete mucosal healing. There are few reports on investigations that depend on the classification of findings using magnifying NBI observations except honey-comb structure. Some previous studies reported a correlation between magnifying NBI observation and histological activity because magnifying NBI observation is“pin-point”observation. However, the pathological characteristic of UC is diffuse, wide-spread, inflammation. The issue regarding how the“pin-point”observed area takes responsibility for the activity of the whole colon remains important in this field.