Studies on infant diarrhea. II. Absorption of glucose and net fluxes of water and sodium chloride in a segment of the jejunum.

Increased stool losses of water, solute, and organic acids after the ingestion of milk during acute diarrhea of infancy have been related to impaired absorption of carbohydrate (1).We have observed that the osmolality of diarrheal stool water is usually high during periods of milk intake.Furthermore, we have demonstrated that carbohydrate comprises most of the solute content of the stool water and that there exists a recipro- cal relationship between the concentration of this compound and that of Cl-, Na+, and K+.On the other hand, there is a direct relationship between the concentration of carbohydrate and total or- ganic anions.Similar effects of carbohydrate on stool volume and acidity have been described when specific disaccharidases are deficient (2-9) or when monosaccharide absorption is impaired (10- 13).An obvious assumption is that unabsorbed carbohydrate exerts an osmotic effect in the bowel and constitutes substrate for the generation of organic acids.However, studies directed at veri- fying these assumptions and determining the char- acteristics of these processes at different levels of the small and large bowel have not been per- formed.Our present studies demonstrate that the absorption of glucose by the jejunum is impaired in acute diarrhea of infancy.The studies also show that the associated net movement of fluid into