As we know，Helicobacter pylori is closely related to many gastrointestinal diseases such as chronic gastritis, peptic ulcer disease,gastric carcinoma and gastric mucosa-associated lymphoid tissue lymphoma，as well as extra-digestive diseases such as urticaria and chronic obstructive pulmonary diseases and so on.The diagnosis of H. pylori infection is based on invasive methods requiring endoscopy and biopsy(e.g. histology, culture, rapid urease test, PCR) or on non-invasive methods (e.g. serology, 13C urea breath test, stool antigen test).Histology has the highest specificity among the others,and also allows us to determine the underlying disease and perform antibiotic sensitivity testing.Serological tests are widely available and more appropriate for epidemiological studies, their main weakness for clinical use is low specificity.The 13C urea breath test is the most accurate method in patients irrespective of age.Stool antigen testing,as a promising method, is easy to perform, and its accuracy may be improved by the use of monoclonal antibodies recently proposed for capturing H. pylori antigen in stool specimen.Sensitivity and specificity, usefulness,and limitation of tests should be considered for selection of detection methods of H. pylori. Our objective is to review the current methods that are used for the detection of H. pylori infection among patients with chronic atrophic gastritis.Except that,patients with Hp positive will be further treated with 10-day minocycline-based quadruple therapy,to observe the efficacy and safety of minocycline-based regimen for H.pylori eradication as a first-line therapy.

Consecutive outpatients (18 to 70 years), with endoscopically proven chronic atrophic gastritis will be enrolled in our study.5 different methods，including histology,13C urea breath test,stool antigen test,serological antibody test for H.pylori and serologic test with a current infection marker of H.pylori，will be performed to detect H. pylori infection.And patients with Hp positive will be further treated with 10-day minocycline-based quadruple therapy.Our objective is to compare specificity and sensitivity of the current methods among patients with chronic atrophic gastritis,meanwhile,to observe the efficacy and safety of minocycline-based regimen for H.pylori eradication as a first-line therapy.

Inclusion Criteria:

• participants was confirmed chronic atrophic gastritis by endoscopy
• participants has not been previously received treatment for H.pylori infection.

Exclusion Criteria:

• patients who were allergic to any study medications
• patients who had taken antibiotics,bismuth agent,PPI or H2 receptor antagonist (H2RA) 4 weeks before the study
• patients with previous gastrectomy
• patients with malignancy or severe comorbidity
• pregnant or lactating women
• Patients with poor treatment compliance or could not express themselves correctly
• patients who participated in other drug trial recently (within 3 months of enrollment).