A 16-year-old boy presented with a 2 day history of lower abdominal pain. He had similar symptoms with two admissions over the previous 12 months. Clinical examination revealed lower abdominal distension and a mass. Plain radiograph revealed dilated small bowel and computed tomography (CT) demonstrated ileocaecal intussusception (fig 1).
Laparotomy confirmed ileocaecal intussusception (fig 2A). This was reduced, revealing a loop of necrotic small bowel, and a limited small bowel resection was performed. Examination of the specimen revealed notable ulceration within Peyer’s patches as the lead point of the intussusception (fig 2B), which was confirmed histologically. The patient made an uneventful recovery.
Intussusception involves telescoping of one segment of bowel (intussusceptum) into an adjacent segment (intussuscipiens). It is a relatively common cause of intestinal obstruction in children, but is rarer in adults. Intussusception may be ileo-ileal, ileo-colic or colo-colic, and is rarely seen in the stomach and rectum.
In children under 2 years of age, it is usually caused by enlarged or inflamed Peyer’s patches that serve as a lead point. This is rarely seen in young adults, as in our case. In older children other aetiologies should be considered such as Meckel’s diverticulum and cystic fibrosis.
In adults two varieties are seen, “short segment”, which is self limiting and without a lead mass, and “long segment” or obstructing intussusception, where there is an underlying mass lesion which may be benign or malignant.1 The diagnosis may be difficult due to vague or intermittent symptoms. The investigation of choice is CT in adults and ultrasound in children.2,3