1）Helicobacter pylori感染症

Endoscopic Diagnosis of Helicobacter Pylori Infection

要旨　通常観察に用いる内視鏡画像の高解像度化に伴い，胃粘膜表面の集合細静脈透見像である微細発赤斑が認識可能となった．胃内視鏡観察によりHelicobacter pylori（以下H. pylori）感染の診断を行うために，732例に対して胃粘膜表面を詳細に観察し，萎縮境界および微細発赤斑所見の有用性について検討した．H. pylori感染の診断には血清抗H. pylori-IgG抗体を用いた．内視鏡観察により萎縮境界が判別可能な萎縮性胃炎では，H. pylori感染率は95.4％であった．大きさが均一で鮮明な微細発赤斑を胃粘膜全体に認める群のH. pylori感染率は2.1％と極めて低く正常胃粘膜と考えられた．微細発赤斑が不明瞭な群で，かつ萎縮境界不明瞭な群は，萎縮のない粘膜に起きた種々の炎症と考えられ，そのH. pylori感染率は96.2％であった．以上より，H. pylori感染は胃粘膜の詳細な観察により診断可能であり，その内視鏡所見の特徴は，微細発赤斑の大小不同や不鮮明化であると考えられた．

　By using high-resolution electronic endoscopy, it becomes easy to observe in detail, the red-spot pattern, which is regarded as formed by lucent collecting venules on the gastric mucosa. To diagnose the Helicobacter pylori (H. pylori) infection by using this type of endoscopy, we pay attention to this red-spot pattern and the atrophic border when we observe gastritis. We compared blood H. pylori-IgG antibody as a judgment standard of H. pylori infection. As a result, the H. pylori infectious rate was shown to be 96.4％(672/697) when the atrophic border was recognized distinctly. When the size of the red-spot pattern was almost uniform and recognized clearly throughout the whole stomach, the H. pylori infectious rate was 2.1％(4/193). This is significantly low rate compared with rates of infection such as 95.5％ (506/530). In conclusion, it is possible to diagnose H. pylori infection by using high-resolution electronic endoscopy, and regarding the atrophic border as it's positive sign and the clear red-spot pattern as it's negative sign.