Bacterial adhesion in human upper gastrointestinal tract.

Small bowel biopsy specimens were taken from 21 patients undergoing gastrointestinal endoscopy to detect a possible adhesion of bacteria to the mucous layer of the upper gastrointestinal tract. In 30 control biopsy specimens taken from 10 patients free from gastrointestinal pathology, no associated bacteria were found, whereas in 23 biopsy specimens taken from eight gastrectomized patients an associated bacterial flora including E. coli or Pseudomonas was grown. Bacterial adhesion was confirmed by means of transmission electron microscopy of the eight patients yielding positive cultures. Bacterial adhesion induced local alterations of the brush border membrane. These results suggest that adherent bacteria may be present in hypochlorhydric patients. Pathophysiologic consequences require further studies.