肉芽腫を認める上部消化管疾患

Upper Gastrointestinal Diseases Presenting Microscopic Granulomas

要旨●肉芽腫を認める上部消化管疾患にはCrohn病やサルコイドーシスなどの肉芽腫性疾患，結核，梅毒，H. pyloriなどの感染症，腫瘍や異物に伴う反応として出現するもの，血管炎に伴うものなどがある．サルコイドーシスや結核では多彩な肉眼形態をとるが，Crohn病や梅毒などでは特徴的な画像所見を呈するため内視鏡所見から疑うことが可能である．特発性肉芽腫性胃炎はこれらの既知の類上皮細胞肉芽腫が認められる疾患を除いた原因不明のものとされるが，限局性サルコイドーシスやH. pylori感染との鑑別は混沌としている．臨床現場で通常の治療に反応しない非典型的な病変に遭遇した際には肉芽腫性胃炎も鑑別に加えることも必要である．

　Granulomatous lesions involved in the upper gastrointestinal tract are rare. These lesions can be found in cases of granulomatous diseases, such as CD（Crohn's disease）and sarcoidosis, and infectious diseases, including tuberculosis, syphilis, and Helicobacter pylori（H. pylori）. They also appear as biological reactions to neoplastic lesions or foreign bodies. Although IGG（idiopathic granulomatous gastritis）is diagnosed by excluding these diseases, it is difficult to distinguish IGG from localized sarcoidosis restricted to the stomach or H. pylori-related GG（granulomatous gastritis）. Endoscopic findings of GG due to CD or syphilis are characteristic, but the morphological features of GG concomitant with other diseases are so varied that diagnosis is difficult by endoscopic and radiographic findings. The possibility of GG should be considered when gastric lesions do not respond to standard medical treatment.