7)好酸球性胃腸炎

Eosinophilic Gastroenteritis

　好酸球性胃腸炎はアレルギー機序により発生すると考えられる炎症性疾患であり消化管への好酸球浸潤により特徴付けられる．胃と小腸に発生することが多いが，まれに食道や大腸にも病変がみられる．消化管壁における好酸球の浸潤部位により ①predominant mucosal disease，②predominant muscle layer disease，③predominant subserosal diseaseに分類されており病像が異なる．画像所見は特徴的所見に乏しいが病変部位と程度により多彩な所見を呈するため，他疾患との鑑別を行う上で，常に本症を念頭に置く必要があると考えられる．治療にはステロイドが著効を示すが，他の抗アレルギー剤が用いられることもある．狭窄や穿孔を来すこともあるため，早期に診断し不可逆的な変化が出現する前に治療を行うことが重要である．

　Eosinophilic gastroenteritis is an inflammatory disorder of allergic nature characterized by infiltration of eosinophils into the gastrointestinal tract. Although it usually involves the stomach and the small intestine, the esophagus and the large intestine are also sometimes involved. His disorder is classified by the site of eosinophilic infiltration into three types : predominant mucosal disease, predominant muscle layer disease, and predominant subserosal disease. Symptoms vary according to the type of disease. Since the findings by imaging modalities also vary according to the extent and degree of the disease, it is important to bear this disorder in mind in diagnosing any gastrointestinal disease. Steroid is very effective for it, but other anti-allergic agents are also used for therapy. If not properly treated, irreversible changes such as stenosis or perforation may ensue, so early diagnosis and treatment is important.