Functional abdominal pain: further evidence that whole gut is affected.

The distribution and referral of abdominal pain in 21 patients with functional abdominal pain were investigated by performing balloon distension of the ileum, proximal jejunum, second part of the duodenum, and distal oesophagus. Pain was perceived not just in classically described sites but throughout the abdomen and was referred to several unusual extra-abdominal sites. The presenting pain was reproduced by this technique in 14 patients, in three of whom it was also reproduced by colonoscopic distension. This study emphasises the protean presentation of functional abdominal pain and demonstrates the existence of potentially tender "trigger" areas for the production of abdominal pain in the proximal as well as the distal gut.