胃粘膜の拡大観察―H. pyloriの感染と胃粘膜の形態診断

Magnified Views of Gastric Mucosa―Diagnosis of Gastric Mucosa and Inflammation Induced by H. pylori

要旨　H. pylori非感染胃の体部には集合細静脈が点状に規則的に配列する像を内視鏡観察で認める．その所見はregular arrangement of collecting venules(RAC)と報告されている．その拡大像はヒトデ状の集合細静脈，ネットワークを形成する真性毛細血管，ピンホール状の腺開口部から形成される．一方，H. pylori胃炎の拡大像では集合細静脈は観察されず白濁し開大した腺開口部やその周囲の発赤隆起した粘膜が観察される．除菌後はピンホール状の腺開口部に改善し，腺開口部周囲の発赤も消失し平坦化していた．組織像との対比により変性した上皮と異常な腺開口部が除菌により正常に復していることが確認され，この変化が拡大像に反映していることが判明した．

　Magnified view of the gastric body of H. pylori-negative normal stomach shows collecting venules, true capillaries forming a network and gastric pits with pinhole-like appearance. Histological features of H. pylori-negative fundic gland mucosa consist of normal surface epithelium, normal gastric pits and fundic gland without atrophy, but there is no inflammation. Magnified view of antral mucosa of H. pylori-negative normal stomach shows a well-defined ridge appearance with minute points in each ridge. Compared with the fundic mucosa, the histological finding of H. pylori-negative pyloric mucosa shows surface epithelium with villi-like-appearance.

　Magnified view of the gastric body of H. pylori-induced gastritis shows white dilated pits and erythema around the pits, but shows neither collecting venules nor true capillaries. Histological features of H. pylori-induced gastritis consist of degenerated surface epithelium and inflammatory cells. After successful eradication, magnified views show the disappearance of erythema around the pits and improvement of the pits from white-dilated type to pinhole-like type. These magnified views correspond to the histological features after successful eradication. There features are improvement from degenerated epithelium to normal epithelium and normalization of the structure of gastric pits.