高年齢者における大腸憩室症―連続剖検1,000例に基づく検討

Diverticular Disease of the Colon among Senile Individuals, from Postmortem Study of 1,000 Consecutive Necropsies

　はじめに

　大腸憩室疾患は，人種や地域によって発症頻度，発生部位，臨床症状の面で著しい差異がある．欧米では，筋層の異常を伴うS状結腸の憩室例が多く，病態の根底をなすものはこの筋層異常であるとの観点から，大腸憩室疾患diverticular diseaseの概念が確立されている．一方，本邦例では，従来より，欧米で極めて少ないとされている右側憩室が主であったが，近年，高年齢者を中心に，欧米型のS状結腸憩室も徐々に報告されはじめ，出血，穿孔などの合併症の問題も生じてきた．しかし，剖検例にょる詳細な頻度や発生部位の検討，さらに，本邦では欧米型の筋層異常は存在するのか，といった点に関しては，十分に解明されているとはいい難い．

　われわれは，主として60歳以上の高年齢者よりなる連続剖検1,000例の大腸検索により，高年齢者における大腸憩室疾患の特徴を検討した，この結果は，今後の本邦症例の病態を考察する上で参考になると考えられる．

　In our country, diverticular disease of the colon mainly locates in the right side and left sided diverticulosis, which has abnormality of the muscle layer and common in Europe and U. S. A., is uncommon.

　However, increasing incidence of the left sided diverticulosis of the colon has been repeated among the senile individuals in our country. To understand characteristics of the senile individuals' diverticular disease and refer to further study of diverticular disease of our country, author et al precisely examined the colon from 1,000 consecutive necropsies which mainly consist of senile individuals and their age was over 60.

　1) We found diverticular disease in 173 cases (17.3%).

　Their locations were as follows : appendix 12, cecum 14, ascending colon 25, transverse colon 4, descending colon 4, sigmoid colon 67, rectum 0, ceco-ascending colon 7, descending-sigmoid colon 15 and both sides of the colon 25. These figures indicate that left sided diverticular disease is common among the senile individuals.

　2) In more than 70% of the diverticular disease of the sigmoid colon, we found shortening of the taenia and muscle abnormality characterized by hypertrophy of the inner circular muscle which we demonstrated by histological sections. On the other hand, there were no significant musculer abnormalities in the right sided diverticular disease but showed only mild muscle hypertrophy in the case of multiple diverticula.

　3) We studied abdominal symptoms by analyzing the location of diverticular disease and examining the presence of muscle abnormalities. It was disclosed that abdominal symptoms were more common in left sided diverticular disease as well as in the case muscle abnormalities. Above findings showed that diverticular disease of the colon in our country will be the usual right sided one plus left sided one which has muscle abnormalities.

　Therefore, we emphasized that it is necessary to study muscle abnormalities to elucidate pathophysielogy of diverticuler disease in our country.