We determined the point mutations of 23S rRNAgyrase A. We showed that the point mutations at 21422143 of 23S rRNA correlated well with clarithromycin resistance of H. pylori. Point mutations at gyrase A correlated well with levofloxacin resistance. The successful rate of genotypic resistance determination using gastric biopsy specimen was 98.

Determination of the minimum inhibition concentration of antibiotics against H. pylori is time consumingthe successful culture rate is lower than 90. We showed that the point mutations at 21422143 of 23S rRNA correlated well with clarithromycin resistance of H. pylori. Point mutations at gyrase A correlated well with levofloxacin resistance. The successful rate of genotypic resistance determination using gastric biopsy specimen was 98.

This technique can be used for tailored therapy for H. pylori eradication. We are developing techniques to determine the genotypic resistance of H. pylori using fecal samples. We expect that genotypic resistance guided therapy can improve the efficacy of H. pylori eradication therapyavoid the use of unnecessary antibiotics in clinical practice.