The contribution of the colon to electrolyte and water conservation in man
Phillips, S.F.; Giller, J.
Journal of Laboratory and Clinical Medicine 81(5): 733-746
1973
ISSN/ISBN: 0022-2143 PMID: 4698660 Document Number: 68174
The compositions of terminal ileal contents and faeces were compared in 5 healthy subjects and in 2 patients with diarrhoea; continuous sampling of the ileum was done during the slow infusion of a nonabsorbable marker under standard dietary conditions. Colonic inflow, faecal output and colonic absorption were estimated. With a standard diet in health, 1500 ml water, 200, 100, 10, 15 and 9 m-equiv of Na, Cl-, K, Ca and Mg, respectively, entered the colon daily. Faecal excretion of water, Na, Cl- and K was small, and the colon absorbed more than 95% of the Na, Cl- and water and 50% of the K traversing the ileocaecal region. Small values for mean absorption of Mg and secretion of Ca by the colon were also found. In a patient with severe nontropical sprue in relapse, colonic inflow was more than twice that in health and, despite colonic reabsorption of 3000 ml of water and electrolytes each day, severe diarrhoea was present. In a patient with ileal resection and severe diarrhoea, which was corrected by cholestyramine, excessive faecal volume was caused in part by colonic dysfunction. In 2 healthy subjects, the volume and the electrolyte content of the proximal ileum were about 50% greater than those of the terminal ileum.