SINGLE AND MULTIPLE STRAIN COLONIZATION IN PATIENTS WITH HELICOBACTER-PYLORI-ASSOCIATED GASTRITIS - DETECTION BY MACRORESTRICTION DNA ANALYSIS

Helicobacter pylori isolates from 18 patients were examined by macrore striction DNA analysis to determine whether greater than or equal to 2 strains can coexist in the human stomach. Four biopsy samples from di fferent sites in each patient's stomach were cultured, and 12-14 clone s of H. pylori per patient were analyzed. DNA of 15 of the 18 isolates was digestible: 12 by NotI and 3 by NruI. Within 14 of these digestib le isolates, the patterns of all clones were identical. The isolate of 1 patient showed two digestion patterns, a finding that was confirmed by arbitrary primer polymerase chain reaction. The typeable isolates of all patients, except 2 who underwent gastroscopy on the same day, d iffered markedly from each other. These results indicate a noticeable discrepancy between the pronounced interpatient heterogeneity and the rare intrapatient variation of H. pylori.