Colonic absorption in idiopathic constipation.

Abstract

All patients seen for constipation between September 1, 1969 and September 1, 1971 were investigated by a protocol designed to exclude those whose symptoms were related to specific etiologies. Nine patients, aged 15 to 31, fulfilling the criteria for idiopathic constipation, and 26 healthy volunteers were studied by colonic perfusion. Mean transit times of solutions infused at 10 and 16 ml per min were 83 and 53 min respectively in patients with constipation, and 40 and 29 min in control subjects. Colonic volumes during these perfusions were respectively 485 and 604 ml in patients, and 351 and 397 ml in control subjects. Although total net absorption of water and sodium was greater in constipation, when rates of absorption were corrected for transit times, constipated subjects absorbed water and sodium at a slightly lower rate than in health. In another part of the protocol, transit time was studied by the use of radio-opaque markers and was found to be markedly slower in constipated patients. Increased water absorption in the colon of patients suffering from idiopathic constipation appears to be related to delayed transit, rather than to altered mucosal function. It is possible to speculate that a degree of anorectal obstruction could be responsible for all the observed findings.