Intussusception revisited: clinicopathologic analysis of 261 cases, with emphasis on pathogenesis.

In the ten-year period from 1978 through 1987, 261 patients with intussusception were admitted to Chang Gung Memorial Hospital. The diagnosis was established by barium enema or at laparotomy. The patients were divided into two groups; there were 228 children ranging in age from 1 month to 14 years, and 33 adults. Among the children, 134 (59%) were male and 94 (41%) were female, a ratio of 1.4:1. There was no clear seasonal incidence. The age group most commonly affected was between 3 and 11 months of age (72.4%). The classic triad of abdominal pain, vomiting, and rectal bleeding was encountered in 187 cases (82%). Two hundred one cases (88%) were idiopathic, without any definite leading point. In these cases, the ileocecal area was the site most commonly involved (82%), hypertrophic Peyer's patches of the terminal ileum being responsible for 39% of the idiopathic intussusceptions in the ileocolic area. Enlargement of the mesenteric lymph nodes occurred in 67 of the idiopathic cases (33%). Local pathology or the leading point precipitating intussusception was found in 27 cases (12%); there were eight benign tumors, six malignant tumors, and 13 tumor-like lesions. In 32 of the 33 cases in adults, there was a definite contributing pathologic entity, including 18 benign tumors, 11 malignant tumors, and three tumor-like lesions. In infants and young children, there is usually no apparent predisposing disease, and a contributing or causative local pathologic lesion is seldom found. In contrast, intussusception in adults is almost invariably caused by some preexisting lesion involving the bowel wall. Furthermore, trauma, lymphoid hyperplasia, pregnancy, and viral infection may be possible predisposing factors in the production of intussusception.