Gastric microbial flora in patients with gastrointestinal disease.

We designed a prospective study to test the hypothesis that the stomach may be a bacterial reservoir in some patients and function as a potential source of aspiration-induced bacterial pneumonia. Quantitative cultures of fasting gastric contents were obtained in 100 consecutive patients having fiberoptic endoscopy for evaluation of gastrointestinal disease. Culture results were correlated with gastric pH and gastrointestinal pathology. Patients with gastric ulcer disease had a significantly higher incidence of bacterial growth than those with duodenal ulcer. Patients who had had gastrectomy were more likely than any others to have gram-negative bacilli in their stomach. A somewhat high frequency of other common pneumonic pathogens in gastric contents was also noted. The significance of these findings in the production of pneumonia in the elderly is discussed.