若年者のH. pylori感染症

Clinical Feature of H. pylori-associated Gastritis in Young-adulthood

要旨　近年，若年健常者のH. pylori感染率は過去30年間で著しく低下しており，組織学的胃炎も有意に軽減し，H. pylori陽性者における胃炎の分布は，欧米に多い幽門部優位型胃炎が増加していた．また，H. pylori陽性若年者の内視鏡的胃炎の特徴は軽度な萎縮性胃炎と鳥肌胃炎であった．若年者H. pylori胃炎の典型である鳥肌胃炎の内視鏡像は，顆粒状～結節状隆起が前庭部から胃角部を中心にほぼ均等に分布し，拡大観察にて隆起の中心には陥凹した白色斑点が認められるのが特徴である．また，鳥肌胃炎は若年者胃癌のリスク群でもあり，合併する胃癌の特徴は胃体部に発生する未分化型胃癌であった．将来的な胃癌予防のため，若年者のH. pylori陽性胃炎はできるだけ早期の除菌治療が望ましいと考えられた．

　Our study and other reports showed that the rate of H. pylori infection has recently decreased in healthy young-adulthood. Additionally, our study showed that the degree of histological gastritis has also decreased and antrum-predominamt gastritis has increased as in Western countries. The feature of endoscopic gastritis in H. pylori-positive young-adulthood was mild atrophic gastritis and nodular gastritis.

　The endoscopic findings of nodular gastritis were mainly characterized by a unique, small granulated pattern in the antrum and angulus, and slightly depressed white spots were observed in the center of each nodularity. The cases of gastric cancer with nodular gastritis showed the same characteristics : all were diagnosed histologically as the diffuse type and were located in the corpus with H. pylori infection. We recommend that in patients with nodular gastritis, endoscopists should carefully examine not only the antrum but also the corpus. H. pylori should be eradicated as soon as possible to prevent gastric cancer in young patients with H. pylori-associated gastritis including nodular gastritis.