The interplay between mutations in cagA, 23S rRNA, gyrA and drug resistance in Helicobacter pylori.

In this study, we evaluated the mutations of Helicobacter pylori associated with resistance to clarithromycin and levofloxacin. Furthermore, based on the proposed interaction between antimicrobial resistance and pathogenicity, we correlated the mutation profiles of the strains with the presence of the pathogenicity gene cagA. We analyzed 80 gastric biopsy specimens from H.

Detection of Helicobacter pylori CagA EPIYA in gastric biopsy specimens and its relation to gastric diseases.

CagA of Helicobacter pylori undergoes tyrosine phosphorylation in a region containing differing numbers of repeat sequences (EPIYAs), which can result in a modulation of the inflammatory response. This study investigated whether the presence of CagA EPIYA variations in strains of H. pylori that are positive for this region contributes to differing degrees of disease severity in the gastric mucosa.