Background: It has not been fully confirmed whether the detection of Helicobacter pylori  resistance gene mutation can replace antibiotic drug sensitivity test to guide the clinical individualized treatment. Therefore, we have studied this aspect and discussed the application value of antibiotic sensitivity gene test.
Materials and Methods: The biopsy specimen of gastric mucosa from the patients examined by endoscopy and positive for rapid urease test were collected continuously for histopathological analysis, H. pylori  culture, antibiotic drug sensitivity test (E-test drug sensitivity test), and antibiotic sensitivity gene test (high-throughput nucleotide sequencing). The participants received triple plus bismuth solution eradication treatment (esomeprazole 20 mg, amoxicillin 1000 mg, clarithromycin 500 mg, and bismuth potassium citrate 220 mg, twice daily for 14 days) for follow-up, and the eradication effect was determined.
Results: The 551/602 subjects, who met the inclusion criteria, were subjected to culture for H. pylori  and antibiotic drug sensitivity determination; among them 506 were cultured successfully. The results showed that the resistance rates of H. pylori  were 38.9% for clarithromycin and 31.0% for levofloxacin. In 489 H. pylori  strains, the mutations were detected in clarithromycin and levofloxacin resistance genes, indicating the genotype resistance. The resistance genes of clarithromycin and levofloxacin were consistent with phenotype resistance with respect to sensitivity (81.2% and 69.7% for clarithromycin and levofloxacin, respectively) and specificity (88.9% and 93.7% for clarithromycin and levofloxacin, respectively). The eradication rate of H. pylori  in the clarithromycin-resistant group was significantly lower than that in the sensitive group (ITT: 52.1% vs 85.0%, P < 0.001).
Conclusion: A correlation was established between the resistance genes of clarithromycin and levofloxacin and their phenotypic resistance and clinical efficacy. The detection of H. pylori  resistance genes has a good clinical application prospect.
Keywords: Helicobacter pylori , drug resistance, clarithromycin, levofloxacin, mutation, high-throughput nucleotide sequencing