難治性潰瘍性大腸炎に対する最新の治療法―本邦と欧米の現況

The Latest Therapy for Refractory UC-present Situation of Japan and Western Countries

要旨　本邦では，難治性潰瘍性大腸炎（UC）の急性期寛解導入治療としてシクロスポリン持続静注，タクロリムス経口投与，インフリキシマブ（IFX）点滴静注，血球成分除去療法などが選択される．シクロスポリン（CsA）は効果発現が早いため，迅速な判断が要求される重症度の高い症例に推奨される．血球成分除去療法は重症度がそれほど高くない中等症に推奨される．欧米では，急性期寛解導入治療には主としてCsAとIFXが用いられている．難治性UC活動期の救済治療としてCsA，タクロリムス，IFXの短期成績は良好で，改善率はそれぞれ約80％，約70％，約70％とする報告が多いが，今後さらなる検証が必要である．いずれの薬剤においても長期成績は良好とは言えず，半数に及ぶ症例が最終的に手術を余儀なくされている．難治性UCの寛解維持治療としてはアザチオプリンや6-MPが原則として使用されるが，IFXで寛解導入ができた例では寛解維持にIFXの8週ごとの維持投与が選択可能である．

　In Japan, cyclosporine, tacrolimus,IFX（infliximab）, and cytaheresis are opted as rescue therapies to induce the remission of refractory UC（ulcerative colitis）. Because cyclosporine has a quick effect, it is recommended for cases with sever colitis that demands a quick judgment. Cytaheresis is recommended for the moderate disease that severity is not so high.

　In Europe and America, cyclosporine and IFX are mainly used as rescue therapies to induce the remission of refractory UC. The short-term results of cyclosporine, tacrolimus and IFX are good as rescue therapies for active refractory UC and many reports show the improvement rates are approximately 80％, 70％ and 70％, respectively, but they require further inspection in the future. The long-term results are not so good in any of these medicines and, in half of the cases, surgery has to be postponed to after all.

　Azathioprine and 6-MP are generally used for maintenance therapy for remission of refractory UC, but the every eight weeks administration of IFX can also be selected for maintenance therapy for in cases where remission was induced by IFX.