病態生理の立場からみた胃潰瘍の治癒判定

Endoscopic Confirmation of the Complete Healing of Gastric Ulcer, with Special Reference to Its Pathophysiological Background

要旨　胃潰瘍の内視鏡的治癒判定は従来，白苔が消失した時期をもってなされてきた．その多くは赤色瘢痕がこれに相当する．われわれは多年ヒト胃潰瘍の切除胃について，内視鏡像，実体拡大像，走査・透過電顕像および組織像などの相関を求めて，胃潰瘍の治癒過程を観察してきた．実体拡大像では，初期（A₁～A₂），成長期（H₁～H₂），柵状瘢痕期（S₁）および敷石状瘢痕期（S₂，一部S₁）に分類される．柵状瘢痕期は敷石状瘢痕期に比べると，再生上皮の性状は形態的機能的両面において未成熟の段階にあり，分化の途上にある幼若細胞が単に潰瘍面を覆いつくしたにすぎない．また，赤色瘢痕における再発頻度も高い．したがって潰瘍の治癒判定にはS₁またはS₂と明記すべきである．

　Sakita et al have reported a useful classification of the three stages of gastric ulcer based on endoscopic findings : namely active stage (A₁-A₂), healing stage (H₁-H₂) and scarring stage (S₁-S₂). While we have employed this system of classification and have found it useful, we have long felt the need for a clearer understanding of the correlation of gastric ulcer healing process by endoscopy, dissecting microscopy, scanning or transmission electron microscopy and histology. Four stages of gastric ulcer could be classified by dissecting microscopy ; initial stage, growing stage (Fig. 1 a), palisade scar stage (Fig. 1 b) and cobblestone scar stage (Fig. 2). The palisade scar stage corresponds to Sakita's S₁ (red-scar) stage and is immature phase of a differentiating process as compared with the cobblestone scar stage (Sakita's S₂-white scar) from the electron microscopic and histochemical findings (Fig. 3, 4, 6～8). In eight patients with gastric ulcer scar, the effect of secretin on gastric mucosal blood flow was investigated, using an endoscopic hydrogen gas clearance method. There was a significant increase of 49.8% in blood flow in the scarred area, which revealed higher increasing rate in Si stage than in S₂ stage (Fig. 9).

　Previous reports have shown that the recurrence rate of gastric ulcer closely correlates with the endoscopic scarring stage present at the time of withdrawal of drug therapy. From our study on the prevention of gastric ulcer recurrence using sucralfate, the high recurrence rate was obtained in patients with red-scar healing as compared with white-scar healing (Fig. 10), suggesting that complete healing of gastric ulcer should be assessed after endoscopic confirmation of Sakita's S₂ stage from the morphological and functional standpoint of regenerated epithelium.