IntroductionInadequate antimicrobial treatment has led to multidrug-resistant (MDR) bacteria, includingHelicobacter pylori(H.pylori), 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 ofH.pyloriresistance on the diversity and abundance of the stomach microbiome.MethodsBacterial DNA was extracted from biopsy samples of patients presenting dyspepsia symptoms withH.pyloripositive from cultures and histology. DNA was amplified from the V3-V4 regions of the 16S rRNA gene. In-vitro E-test was used to detect antibiotic resistance. Microbiome community analysis was conducted through α-diversity, β-diversity, and relative abundance.ResultsSixty-nineH.pyloripositive 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 (allP<0.05). A notable change was observed in triple-resistant compared to sensitive (P<0.05) and double-resistant (P<0.05) groups. Differences in β-diversity by UniFrac and Jaccard were not significant in terms of the resistance (P= 0.113 andP= 0.275, respectively). In the triple-resistant group, the relative abundance ofHelicobactergenera was lower, whereas that ofStreptococcusincreased. Moreover, the linear discriminant analysis effect size (LEfSe) was associated with the presence ofCorynebacteriumandSaccharimonadalesin the single-resistant group andPseudomonasandCloacibacteriumin the triple-resistant group.ConclusionOur results suggest that the resistant samples showed a higher trend of diversity and evenness than the sensitive samples. The abundance ofH.pyloriin 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.