隆起性病変を呈した直腸孤立性潰瘍症候群の1例

Solitary Ulcer Syndrome of the Rectum with Multiple Polypoid Lesions, Report of a Case

要旨　患者は15歳男性．主訴は血便，残便感である．直腸鏡および大腸内視鏡検査では肛門管直上の下部直腸に全周性のポリープ様隆起性病変を認めた．生検にて非腫瘍性腺管の増生と，粘膜固有層に平滑筋線維を認めた．直腸の孤立性潰瘍症候群の診断にて，経肛門的に病変部を切除した．切除標本の検索にて，非腫瘍性腺管の絨毛状の増生，びらん，fibromuscular obliterationなどが認められ，直腸孤立性潰瘍症候群と診断した．ポリープ状の隆起性病変を呈する本症の場合には，内視鏡所見では腺腫や癌との鑑別が問題となり，的確な診断を下すには，生検組織における上記の所見が重要なポイントとなる．

　A fifteen year-old male patient was admitted with chief complaints of rectal bleeding and a sense of incomplete defecation. On proctoscopy and colonoscopy, a nodular polypoid lesion was seen in the lower rectum just above the anal canal. The polypoid lesion occupied the entire circumference of the lower rectum. Biopsy specimens showed non-neoplastic glandular epithelium with papillary structure and smooth muscle fibers in the lamina propria. Diagnosis of solitary ulcer syndrome of the rectum was made. Resection of the polypoid lesion was performed by transanal approach. At operation it was disclosed that the polypoid lesion was actually a complex of five separate smaller lesions. Histology of the resected specimen showed villous hyperplasia of non-neoplastic glandular epithelium, erosion and fibromuscular obliteration. These histological findings confirmed the diagnosis of solitary ulcer syndrome. After the operation the patient was advised not to strain longer than 5 minutes on defecation. The patient has been asymptomatic for 4 months after the operation. In cases of polypoid type solitary ulcer syndrome of the rectum, it is not easy to differentiate the disease from adenoma or carcinoma of the rectum. Histological findings of the biopsy specimens, particularly fibromuscular obliteration, is important to make a correct diagnosis.