CYTOTOXIN PRODUCTION BY HELICOBACTER-PYLORI FROM PATIENTS WITH UPPER GASTROINTESTINAL-TRACT DISEASES

A cytotoxin produced by some Helicobacter pylori strains has recently been identified, The cytotoxin induces intracellular vacuolization of cultured cells, The aim of the present study was to examine the freque ncy of occurrence of cytotoxin-producing strains of H. pylori from sub jects with upper gastrointestinal disease including nonulcer dyspepsia , gastric and duodenal ulcer disease, gastroesophageal reflux disease, and gastric cancer Broth culture filtrates of clinical isolates of H. pylori recovered from 175 patients were used to inoculate Vero and He La cell monolayers for the detection of vacuolating cytotoxin activity , The results obtained demonstrated that the highest percentage of str ains producing cytotoxin were found in subjects with peptic ulcer dise ase (gastric ulcer, 65%; duodenal ulcer, 66%; P < 0.01 compared with n onulcer dyspepsia, 38%). Of the 11 patients with gastroesophageal refl ux disease, 4 of 5 patients in this group who had esophageal ulcers, w ere found to be infected with strains that produced cytotoxin, Three o f the four patients with carcinoma of the stomach were also found to b e infected with cytotoxic strains of H. pylori. With increasing severi ty of mucosal damage in subjects with a normal upper gastrointestinal tract, macroscopic gastritis, duodenitis, and peptic ulceration, there were corresponding increase in the proportion of strains producing cy totoxin; these increases were 32, 46, 50, and 66%, respectively, H. py lori strains from subjects with ulcer disease commonly produced vacuol ating cytotoxin, suggesting that it may be a virulence factor in the p athogenesis of peptic ulcer disease.