Prevalence of antibiotic resistance of Helicobacter pylori isolates in Shanghai, China.

The resistance rates of to amoxicillin, tetracycline, and furazolidone were low, whereas the resistance rates of to clarithromycin, levofloxacin, and metronidazole were high, especially in re-treated patients. Our results indicate that the clinical resistance patterns of clarithromycin and levofloxacin could be guided by relevant gene mutations.