Stool losses and acidosis in diarrheal disease of infancy

1. Simultaneously obtained specimens of serum and stool were obtained from infants with diarrheal disease. From the majority of patients these were obtained at a juncture in the disease where acidosis and dehydration had supervened. The pH, osmolality, and chemical composition of 19 sera and 33 stools from 28 patients were determined. In 24 of the 33 stools the pH was below 7.00. Only 5 stools contained more than 10 mM of CO2 per liter. 2. Analysis of the data obtained for the concentrations of inorganic cations and anions shows, in keeping with all previous analyses of such stools, that appreciable quantities of unidentified organic anion exist in the water phase of the stool. The mechanism by which the loss of such anion, regardless of the stool pH, could contribute acid to the body fluids is discussed. 3. When the data obtained in this study are considered in terms of known maximal and minimal diarrheal daily stool volumes, it appears that, unless fecal volume is extremely large, the acid contributed by the stool loss is within the normal range of renal excretory ability. This is in accord with the original postulates of Howland and Mariott and of Schloss, that reduction in renal excretory function secondary to dehydration is the primary cause of the acidosis in infantile diarrhea.