逆流性食道炎とBarrett上皮

Reflux Esophagitis and Barrett's Epithelium

　1950年，Barrett¹⁾により円柱上皮性食道（columnar epithelial lined lower esophagus）の存在が指摘された．Barrettは先天性短食道として報告したが，その後1957年，Barrette²⁾自身，failure of the embryonic lining of the esophagus to achieve normal maturityと報告している．1953年，Allison ＆ Johnstone³⁾も同様な見解で，短食道あるいはectopic gastric mucosaによるとしている．1960年になり，Goldman ＆ Beckman⁴⁾は術後逆流性食道炎による二次的な“Barrett食道”の症例を報告した．以降，Hayward（1961）⁵⁾，Mossberg（1966）⁶⁾，Burgess（1971）⁷⁾，Halvorsen（1975）⁸⁾，Savary ＆ Miller（1978）⁹⁾らは，実験的または組織学的に後天性“Barrett食道”説を支持し，現在に至っている．

　しかしながら，Barrett食道腺癌の報告をみると，胃底腺で構成された例¹⁰⁾と，後天性化生性偽幽門腺円柱上皮例¹¹⁾とが，それぞれ報告されており，両者が存在することもまた事実と考えられる．したがって，臨床的にはBarrett上皮が，後天性に形成されうるとする立場から，炎症との関係をみた．

　We experienced 1,108 cases of esophagitis (without postoperative esophagitis) and 172 cases of Barrett's esophagus between 1966 and March, 1983. Among them, 916 cases have reflux esophagitis which accompanied 163 cases of Barrett's epithelium. The rest of 192 cases were non-reflux esophagitis which accompanied nine cases of Barrett's epithelium. Early Barrett's esophagus was accompanied by esophagitis and an association rate between Barrett's esophagus and reflux esophagitis was 95%. Definite diagnosis of our Barrett's esophagus and reflux esophagitis was made by endoscopy because of following reason: Only 40 cases which had esophageal stricture and hiatus hernia were definitely diagnosed by x-ray but others had merely suspicious findings.

　Among the Barrett's esophagus, ulcer type was 57 cases (33%). As regard to associated lesions of Barrett's esophagus, hiatus hernia was seen in 61% of Barrett's ulcer and in 49% of Barrett's epithelium. However, it became more than 90% when decreased LES pressure was included ―suggesting that the cause of Barrett's epithelium was reflux. Regarding mucosal findings, 95% of Barrett's ulcer and 71% of Barrett's esophagus accompanied inflammation, furthermore 66 cases which were done biopsy showed high incidence of gastric or intestinal metaplasia.

　The Barrett's epithelium was seen mainly in older patients and it was considered as acquired phenomenon. We reported that reflux esophagitis, hiatus hernia, decreased LES pressure as well as inflammation of Barrett's columnar epithelium are playing important roles on formation of Barrett's epithelium.