PCR-RFLP and antimicrobial susceptibility profiles of Helicobacter pylori isolated from antrum and corpus of dyspeptic patients in Thailand

The study determined the genetic heterogeneity of Helicobacter pylori isolates from antrum and corpus of the same dyspeptic patients in a Thai population and determined the relationship between the antimicrobial susceptibility (AS) profile (antibiogram) and PCR-restriction fragment length polymorphism (PCR-RFLP) pattern. One hundred and nineteen H. pylori isolates comprising 7 single and 56 paired antrum and corpus isolates obtained by gastric biopsy from 160 dyspeptic patients were analyzed. For PCR-RFLP, the 820 bp amplicon of ureC was digested with Sau3AI and HhaI, which revealed 16 (A-Q) and 19 (a- s) different PCR-RFLP patterns after Sau3AI and HhaI digestion, respectively. Combination of the restriction enzyme digestion patterns resulted in 35 distinct RFLP types. Among the 56 paired isolates, 47 were infected with H. pylori having the same AS and PCR-RFLP profiles, 7 with different AS profiles but the same PCR-RFLP profiles and 2 with different PCR-RFLP profiles but the same AS profiles. No patient was infected with H. pylori different in both PCR-RFLP and AS profiles. The results indicate that the majority of the paired H. pylori isolates displayed identical AS profile and PCR-RFLP patterns suggesting that most patients were infected with a single strain. Some patients could have been infected with single strains that were different in the AS profiles.