title: "Scoping-around" a sigmoidorectal intussusception: a pitfall of flexible sigmoidoscopy.
abstract: A 66-year-old woman presented with 3-month history of progressive constipation and occasional bright red per-rectal bleeding. An urgent flexible sigmoidoscopy (FS) showed an abnormal lesion within the anal canal and biopsy showed tubulovillous adenoma with low-grade dysplasia. She mentioned "no" response to a preparatory enema given before FS. The patient presented 4 days after FS with absolute constipation and passing a "jelly-like" substance since the procedure. A large soft tissue lump with "currant jelly" mucus discharge was noted on per-rectal examination. An abdominal x ray was suggestive of distal large bowel obstruction and a water-soluble contrast enema suggested sigmoidorectal intussusception. The intussusception was irreducible with rigid sigmoidocopy and therefore the patient underwent sigmoid resection and Hartmann's procedure, which showed a distal sigmoid polyp as a lead point for the intussusception. Retrospectively looking into the case, the intussusception was present during FS, but was scoped-around and therefore lesion was considered to be in the anal canal.
authors.affiliation: King's Mill Hospital, Mansfield Road, Sutton-in-Ashfield, Nottinghamshire NG17 4JL, UK.
authors.forename: Abdul
authors.initials: A
authors.lastname: Hakeem
authors.forename: Krishnamurthy
authors.initials: K
authors.lastname: Badrinath