X線・内視鏡所見からみたcap polyposisと粘膜脱症候群の異同

Radiographic and Endoscopic Differences Between Cap Polyposis and Mucosal Prolapse Syndrome

要旨　隆起型直腸粘膜脱症候群（MPS）10例とcap polyposis（CP）6例の臨床像およびX線・内視鏡像を比較検討した．臨床像では，CPで下痢・粘液便を来し低蛋白血症を伴う症例が多かった．X線・内視鏡像では，隆起型MPSは直腸前壁側を主座とした立ち上がりのなだらかな単発ないし多発隆起として認められ，粗大結節状隆起を主体とするもの（7例）と粘膜肥厚様隆起を主体とするもの（3例）に大別された．一方，CPでは直腸からS状結腸に全周性に多発する境界明瞭な隆起を認め，直腸病変は粗大結節状隆起を主体とするもの（4例）と平盤状隆起を主体とするもの（2例）に大別されたが，口側大腸の病変は両者で類似していた．また，CP全例で介在する平坦粘膜に白斑を認めた．以上より，隆起型MPSとCPの鑑別は臨床像とX線・内視鏡像からある程度鑑別可能と考えられた．

　In order to clarify the difference between cap polyposis (CP) and mucosal prolapse syndrome (MPS), radiographic and endoscopic appearance was investigated in six cases of CP and 10 cases of MPS. Hypoproteinemia was noted in four cases of CP. Radiographically, multiple protrusions, predominantly located in the anterior wall of the rectum, were characteristic of MPS, while protrusions were located circumferentially in the rectum and the proximal part of the colon in CP. Under endoscopy, whitish nodular protrusions were found in seven cases and edematous mucosa in three cases of MPS. The rectal protrusions of CP were characterized by reddish nodular protrusions in four cases and by flat-topped protrusions with central depression in two cases. However, the configuration of the protrusions in the proximal part of the colon was similar in all cases of CP. Diminutive white specks were observed in the intervening mucosa of CP, while such specks were not found in MPS. Based on these findings, we concluded that CP should be distinguished from MPS.