海外におけるGERDの診断基準（Lyon consensus，Rome Ⅳなど）

Diagnostic criteria of GERD outside Japan (Lyon consensus, Rome Ⅳ, etc.)

要旨

本邦のガイドラインでは，胃食道逆流症（GERD）は「胃食道逆流により引き起こされる食道粘膜傷害と煩わしい症状のいずれか，または両者を引き起こす疾患」と定義されている。食道粘膜傷害を認める「逆流性食道炎」と食道粘膜傷害はみられないものの，逆流症状が認められる「非びらん性逆流症（NERD）」に分類される。逆流モニタリングを行うとNERDはさらに複数の病態に分類することができ，機能性消化管疾患をまとめたRome Ⅳでは，異常酸逆流を認めるものが狭義のNERD，異常酸逆流を認めないものの，逆流イベントと症状とに関連性がみられるものが逆流過敏性食道（reflux hypersensitivity），異常酸逆流を認めず，逆流イベントと症状とに関連性がみられない機能性胸やけ（functional heartburn）と定義された。海外のNERDはこの狭義のNERDのみを意味し，本邦の定義と異なることに注意が必要である。

　Evidence-based clinical practice guidelines for gastroesophageal reflux disease issued in 2021 have defined gastroesophageal reflux disease (GERD) as a condition in which gastroesophageal reflux causes either esophageal mucosal injuries, annoying symptoms, or both. It is classified in Japan into reflux esophagitis with esophageal mucosal injuries and non-erosive reflux disease (NERD) with symptoms. NERD in Japan can be divided into several conditions by reflux monitoring. Rome Ⅳ has defined these conditions as followed. When abnormal acid exposure time (AET) is detected, it is defined as NERD. When AET is normal, but positive symptom reflux association is detected, it is defined as reflux hypersensitivity. When AET is normal and negative symptom reflux association is seen, it is defined as functional heartburn. It should be recognized that the definition of NERD differs between Japan and Western countries.