Heterogeneity of Strains Isolated from Patients with Gastric Disorders in Guiyang, China.

Purpose: Chronic infection causes peptic ulcers in a subpopulation of individuals and is a risk factor for the development of gastric cancer. Multiple infections and heteroresistant contribute to poor treatment efficacy. Here, we investigated the extent of genetic diversity among strains within a given host and its influence on the results of antibiotic (metronidazole, levofloxacin, clarithromycin, amoxicillin, and tetracycline) susceptibility testing.