cap polyposisと粘膜脱症候群はどう違うのか―臨床所見・治療経過を中心に

What is the Difference Between Cap Polyposis and Mucosal Prolapse Syndrome?

要旨　CPは粘液下痢便，腹痛などを主訴とし，著明なTP，ならびにAlbの低下を来す．病変はS状結腸を主体として口側部位にまで拡がる．白色やびらんを伴ったcapで被われた平坦状や広基性ポリープとして把えられ，粘膜ひだの頂部に輪状にみられ，散在性に存在する．capは炎症性肉芽組織より成り，その他の粘膜表層の萎縮，線管の過伸展，粘膜固有層における軽度の細胞浸潤，血管増生，筋線維症などの病理所見はMPSに類似する．MPSは下血を主症状とし，若年者のstrainerで粘膜脱を伴うことが多い．主として直腸前壁の隆起型，あるいは潰瘍型の病変としてとらえられる．両疾患は病理組織所見において類似するが，臨床像や治療経過を加味すれば異なるentityにあるものと考えられる．

　The symptoms of cap polyposis (CP) are mucous diarrhea and abdominal pain, and CP may cause marked reduction in serum total protein and albumin. Lesions are mainly located in the sigmoid colon and may extend to the oral side of the colon. The lesions consist of flatly elevated or wide-based polyps covered with cap with whitish slough and erosion on the top. The circularly arranged lesions are seen scatteredly on the apices of the circular mucosal folds. The cap consists of inflammatory granular tissue. The other pathological findings of CP such as superficial mucosal atrophy, hyperextension of the glands, mild cellular infiltration, neovascularization and muscular fibrosis in the proper lamina are similar to those of the mucosal prolapse syndrome (MPS).

　The chief complaint of MPS is lower gastrointestinal bleeding and MPS is commonly seen in a young strainer with mucosal prolapse of the rectum. MPS are found mainly as the protruding type or ulcerative type on the anterior wall of the rectum. Although CP and MPS are pathohistologically alike, both of them may be differentiated by clinical pictures and healing process and classified as different entities of the disease.