Ongom Peter A, Lukande Robert L, Jombwe Josephat
Colorectal Surgery Unit, Department of Surgery, School of Medicine, Makerere College of Health Sciences, Makerere University, P O Box 7072, Kampala, Uganda.
BMC Res Notes. 2013 Feb 2;6:42. doi: 10.1186/1756-0500-6-42.
Intussusception is one of the less common causes of intestinal obstruction among adults. It is usually covert (concealed) in its clinical presentation. The ileo-colic type with accompanying anal protrusion is extremely rare. The case at hand is that of both an ileo-colic intussusception with anal protrusion, in the presence of a persistence of both the ascending and descending mesocolons; a case possibly yet to be documented in literature.
A 32 year-old African-Ugandan woman presented with complaints of a mass protruding per anus for 2 weeks. It was reducible and associated with colicky abdominal pain, loose stools, and bloody-mucoid discharge per anus. She had previously had a one and a half month's history of abdominal pain; periodically continuous, while other times colicky in character. Examination and investigations revealed an intussusception with a partial intestinal obstruction. At laparotomy she was found to have an ileo-colic intussusception with a freely mobile colon throughout its length. There were persistent ascending and descending mesocolons, and absent hepatocolic and splenocolic ligaments. The intussusceptum was 'milked' but not completely reducible. A right hemicolectomy was done, with ileo-transverse colonic anastomosis. Histopathological examination revealed no preexisting pathologic lesion as a lead point.
The persistence of the ascending and descending mesocolons (azygosis) best explains the anal protrusion of an ileo-colic intussusception with partial obstruction. In this case zygosis (normal retroperitoneal ascending and descending colonic positioning) failed embryologically. This experience is particularly beneficial to general surgeons, radiologists, gastroenterologists, colorectal surgeons and pathologists.
肠套叠是成人肠梗阻较少见的病因之一。其临床表现通常较为隐匿。伴有肛门脱出的回结肠型肠套叠极为罕见。本文所述病例为既有回结肠型肠套叠伴肛门脱出，同时升结肠系膜和降结肠系膜均持续存在；此病例可能在文献中尚无记载。
一名32岁的非洲乌干达女性因主诉肛门肿物脱出2周就诊。肿物可还纳，伴有绞痛性腹痛、稀便及肛门血性黏液便。她此前有1个半月的腹痛病史，呈周期性持续发作，有时为绞痛。检查及相关检查显示为肠套叠伴部分肠梗阻。剖腹探查发现为回结肠型肠套叠，整个结肠活动自如。升结肠系膜和降结肠系膜持续存在，肝结肠韧带和脾结肠韧带缺如。对肠套叠套入部进行“挤捏”但未完全还纳。行右半结肠切除术及回肠-横结肠吻合术。组织病理学检查未发现作为套叠起始点的既往病理性病变。
升结肠系膜和降结肠系膜持续存在（无融合）最能解释部分梗阻性回结肠型肠套叠的肛门脱出。在此病例中，无融合（正常的腹膜后升结肠和降结肠位置）在胚胎发育过程中出现异常。这一经验对普通外科医生、放射科医生、胃肠病学家、结直肠外科医生及病理学家尤为有益。
