[Genome analysis of Helicobacter pylori by pulsed-field gel electrophoresis]

The molecular epidemiology of total 121 isolates of Helicobacter pylori was analyzed by pulsed-field gel electrophoresis method with restriction enzyme Spe I. Seventy-seven isolates were separated from the clinical samples, 36 isolates from pyloric antrum and the body of stomach of 18 patients and 8 isolates from pyloric antrum of 4 patients that include one colony before and after sterilizing treatment to each patient. Seventy-five in 77 isolates showed different genomic types respectively, and the other 2 isolates had the same genomic type and were suspected to be caused by intersective infection of medical workers or the instruments that used in examination because they were from patients who were examined by gastric microscope in same time and same laboratory. In isolates from 4 patients who were treated by sterilizing method, 2 patients showed same genomic types with that observed before the treatment, and one patient showed an incomplete treatment because the genomic type of its colony was is similar, and another patient could be infected again because its isolates showed different genomic type. In 18 patients whose isolates were separated from pyloric antrum and body of the stomach respectively to each person, isolates of 3 patients showed different genomic types in the two different part of stomach indicating that they had two and more clones of H. pylori.