This study was conducted to investigate the effects of high-dose diphtherapy and bismuth quadruple therapy on H. pylori eradication on intestinal microecology, to clarify the changes in intestinal microbiota diversity and structure before and after the two treatment regimens, and to explore the relationship between different treatment regimens and intestinal microbiota dysbiosis; to further guide the safety and drug resistance of H. pylori eradication by the two treatment regimens. The expected results are to observe the changes of intestinal microbiota diversity and structure before and after treatment with the two treatment regimens.

The trial can be divided into three phases.

1. Enrollment screening phase: patients who had been clearly diagnosed with Hp infection and had not received antibiotic therapy and met the inclusion and exclusion criteria were informed and signed informed consent forms, their basic data information was collected, medical history and laboratory tests before enrollment were taken; if they met the requirements of the trial protocol they were included in the study, and patients' stools were collected for 16S rRNA gene sequencing.
2. Treatment period: Patients were enrolled according to a randomized number table provided in advance by a third party, and patients were randomized in a 1:1 ratio to high-dose diphtherapy and bismuth quadruple therapy to receive 2 weeks of Hp eradication treatment. During the treatment period, patients were provided with written instructions on how to take the medication, instructed on the correct way to take the medication, and improved their compliance; patients were asked to record their symptoms and adverse reactions during the medication period, and were informed of the visiting telephone number and visiting WeChat, so that they could keep in touch with the investigator at any time.
3. Follow-up period: At the end of treatment (i.e., day 14 from the start of treatment), patients were asked to return at that time to have their stools sequenced for 16S rRNA gene, and 6 weeks after the end of treatment (i.e., day 56 from the start of treatment), patients were asked to return at that time to undergo rapid urease test (RUT), 13C/14C-urea breath test (13C/14C-UBT), or fecal Hp antigen test. ) or fecal Hp antigen assay (HpSA), with the results recorded on a CRF form, and the patient's stool collected for 16S rRNA gene sequencing.

Inclusion Criteria:

1. Age 18 to 70 years, regardless of gender.
2. Patients with definite Hp infection (positive for either 13C/14C urea breath test, rapid urease test, and fecal Hp antigen test) and who have not received H. pylori eradication therapy.
3. Voluntary Hp eradication therapy.
4. Women of childbearing potential are required to use a medically advisable form of contraception during the trial and for 30 days after the trial ends.

Exclusion Criteria:

1. Patients who have had a definite diagnosis of Hp infection and have been treated with antibiotic eradication therapy.
2. Patients with contraindications to or allergies to the study drug.
3. Patients with severe organ damage and complications (e.g., cirrhosis, uremia, etc.), severe or unstable cardiopulmonary or endocrine disease
4. Continuous use of anti-ulcer drugs, antibiotics or bismuth complexes (taken at least 2 weeks prior to the screening for Hp infection)
5. Pregnant and lactating women.
6. Having undergone upper gastrointestinal surgery.
7. Have symptoms of dysphagia.
8. Evidence of bleeding or iron deficiency anemia.
9. History of malignancy.
10. History of drug or alcohol abuse within the last 1 year.
11. Systemic application of glucocorticoids, non-steroidal anti-inflammatory drugs, anticoagulants, platelet aggregation inhibitors (except for the use of aspirin ≤100 mg/d)
12. Those with psychiatric disorders.
13. Received other clinical trials within the past 3 months
14. Refusal to sign the informed consent form.