Abstract

The agglutinating antibody responses in duodenal fluid and serum were measured serially in 15 infants with enteropathogenic E. coli gastroenteritis. Peak levels of duodenal agglutinins were recorded eight to 18 days after the onset of symptoms, and the titres fell within the next seven to 14 days. These antibodies were mainly of the IgA class but IgM antibodies were detected early in the response, especially in the youngest infants. Serum antibody responses were detected in eight patients, but they correlated poorly with the titres of intestinal antibodies. No rise in serum antibodies was found in six infants. Further studies are required to determine whether these differences are host-derived or whether they reflect different pathogenic properties of the infecting organisms.