The upper gastrointestinal microflora in relation to gastric diseases and gastric surgery.

The upper gastrointestinal microflora was evaluated in relation to gastric diseases and gastric surgery. Postoperative septic complications and microorganisms found in primary infections were studied in 750 gastric operations. The overall rate of primary infections was 23%. Enterobacteriaceae, enterococci and Bacteroides fragilis were more frequently found in postoperative infections in patients with gastric bleeding or carcinoma. The microbial colonization of the oropharynx, esophagus and stomach was studied in 60 patients. Patients with gastritis, carcinoma and a history of gastric resection harboured more microorganisms in their stomachs than patients with gastric or duodenal ulcers. Patients with gastric carcinoma were colonized with the highest numbers of different microorganisms. The microbial colonization in 23 patients with gastric carcinoma was studied. The tumor was colonized in all patients. Clostridium species were isolated from 57% of the patients. Antibiotic agents used as prophylaxis in gastric cancer surgery should cover both aerobic and anaerobic microorganisms, including B. fragilis. The effect of 400 mg ofloxacin on the microflora in gastric juice was evaluated in 24 patients undergoing gastric surgery. Both the aerobic and anaerobic flora were suppressed on the day of surgery, but increased in number afterwards. There was a significant correlation between gastric pH and the number of microorganisms isolated in the gastric juice. The degree of Campylobacter pylori colonization in relation to other microorganisms on antral mucosal biopsies was investigated in 53 patients with dyspeptic symptoms. Microbial colonization was found in 94% of the patients. Microorganisms other than C. pylori were found irrespective of the diagnoses. C. pylori was with one exception only found in patients with gastritis. No relation between the gastric pH and the microbial colonization of the mucosa was found. The relationship between hospital and catchment area utilization of antimicrobial agents and antibiotic susceptibility of isolated bacteria in primary infections after gastric operations were studied. Over 80% of the antibiotics were used in the catchment area. No major problems with bacterial resistance to antimicrobial agents were found. The pattern of bacterial resistance reflected the use of antimicrobial agents in the catchment area more than that in the hospital.