直腸粘膜脱症候群とcap polyposisの内視鏡所見の異同に関する検討―経過観察例を中心に

Endoscopic Diagnosis and Difference Between Mucosal Prolapse Syndrome of the Rectum and Cap Polyposis

要旨　直腸粘膜脱症候群（MPS）とcap polyposis（cap）の内視鏡所見の異同につき経過観察例を中心に検討した．対象は，内視鏡および組織学的診断でMPSと診断された35例のうち経過観察を行った18例とcap 1例である．MPSは，潰瘍型：23例，平坦型：3例，隆起型：11例に分類され，capと類似するのはMPSの隆起型である．MPSの隆起型は，ポリープ型と粘膜下腫瘍型に大別され，いずれも直腸下部に分布し，いきみの中止で縮小，消失がみられた．capは，低蛋白血症を伴い，直腸上部やS状結腸に全周性に分布し，輪状傾向がみられ，隆起に大小不同や粘液の付着が目立ち経過中縮小，増悪が観察された．両疾患は，病変の分布や内視鏡所見，経過の推移に差がみられ，異なる疾患単位と推察された．

　This paper investigates the difference in the endoscopic findings of mucosal prolapse syndrome of the rectum (MPS) and cap polyposis (CAP). 18 patients of MPS were selected for follow-up observation, from among 35 patients (male: 17 cases 41.5±18.1 years old, female: 18 cases 55.3±16.3 years old) who were diagnosed as MPS by endoscopy and pathological examination and whose lesions were classifed as ulcer type (23 cases), flat type (3 cases) and protruded type (11 cases). The protruded type of MPS is similar to CAP, and the protruded type was divided roughly into the polypoid type and submucosal tumor type. Protruded lesions were distributed at the lower part of the rectum and reduction or disappearance was brought about by desisting from straining. CAP distribution was limited to the rectum and sigmoid colon, and the lesions were circular, different in size and with attached mucus. CAP was associated with low protainemia. The clinical course of MPS was different CAP from that of CAP.

　It is concluded that CAP should be distinguished from MPS because of the difference of endoscopic findings and the clinical course.