The influence of enterogastric reflux on gastric juice bacterial growth, nitrite, and N-nitroso compound concentrations following gastric surgery.

Detailed analyses were carried out in 207 fasting gastric juice samples obtained at endoscopy or with a nasogastric tube from 50 patients with partial gastrectomy, 43 with vagotomy, 20 with gastric carcinoma and 50 controls. Significantly higher mean pH, nitrite and N-nitroso compound (N-NO) concentrations and nitrate-reducing bacterial cultures were noted following partial gastrectomy compared with normal controls and comparable to findings in gastric cancer. A highly significant relationship (p less than 10(-6)) was also demonstrated between pH and N-NO concentrations, highest levels of which were seen following Billroth II gastrectomy, significantly higher (p = 0.02) than Billroth I, whereas the only change observed following proximal gastric vagotomy was a nearly threefold rise in N-NO compared with normal controls. However, vagotomy and pyloroplasty produced gastric juice changes comparable to those seen with gastrectomy and gastric carcinoma. Thus, the most marked changes were observed following surgical procedures involving increased enterogastric reflux and these findings lend further support to the possible involvement of N-nitroso compounds in the development of gastric cancer following both Billroth I and II gastrectomy and vagotomy with pyloroplasty.