Gastric microbiome changes in relation with <em>Helicobacter pylori </em>resistance Analysis

Inadequate antimicrobial treatment has led to multidrug-resistant (MDR) bacteria, including <em>Helicobacter pylori</em> (<em>H. pylori</em>), which one of the notable pathogens in the stomach. Antibiotic-induced changes in the microbiota can negatively affect the host. This study aimed to determine the influence of <em>H. pylori</em> resistance on the diversity and abundance of the stomach microbiome. Sixty-nine <em>H. pylori</em> positive samples were eligible after quality filtering. Following resistance status to five antibiotics, samples were classified into 24 sensitive, 24 single resistance, 16 double resistance, 5 triple resistance. Samples were mostly resistant to metronidazole (73.33%; 33/45). Comparation of four groups displayed significantly elevated α-diversity parameters under the multidrug resistance condition (all <em>P </em>&lt;0.05). A notable change was observed in triple-resistant compared to sensitive (<em>P </em>&lt;0.05) and double-resistant (<em>P </em>&lt;0.05) groups. Differences in β-diversity by UniFrac and Jaccard were not significant in terms of the resistance (<em>P</em>=0.113 and <em>P</em>=0.275, respectively). In the triple-resistant group, the relative abundance of <em>Helicobacter </em>genera was lower, whereas that of <em>Streptococcus </em>increased. Moreover, the linear discriminant analysis effect size (LEfSe) was associated with the presence of <em>Corynebacterium</em> and <em>Saccharimonadales</em> in the single-resistant group and <em>Pseudomonas</em> and <em>Cloacibacterium</em> in the triple-resistant group. <br> Our results suggest that the resistant samples showed a higher trend of diversity and evenness than the sensitive samples. The abundance of <em>H. pylori</em> in the triple-resistant samples decreased with increasing cohabitation of pathogenic bacteria, which may support antimicrobial resistance. However, antibiotic susceptibility determined by the E-test may not completely represent the resistance status.