Approximately 50% of people in the world are infected with H. pylori, and its eradication rate fail to exceed 80% and even fails into an unacceptable range.Various risk factors for infection include lower socioeconomic status, younger age, and geographic location.In the present study, investigators aimed to perform a prevalence survey about risk factors for H. pylori infection.To obtain the higher eradication of H. pylori and find out the relevance between the diverse infection and clinical drug focused on refractory H. pylori infection.

Inclusion Criteria:

1. Age 18~70 years old, male or female, untreated patients.
2. Symptoms of abdominal pain, bloating, acid reflux,belching,nausea,vomiting,heartburn, chest pain, vomiting, melena, etc.
3. Unused antibiotics, bismuth, H2 receptor antagonists or PPI by nearly 4 weeks
4. 13C-labelled urea breath test positive.
5. Agreed to Helicobacter pylori culture and sensitivity testing taken by endoscopy gastric biopsy specimens,and the result of culture was positive.
6. Agreed to Helicobacter pylori eradication therapy and cooperate with the eradication efficacy follow-up survey.

Exclusion Criteria:

1. Severe heart, liver, kidney dysfunction.
2. Pregnant or lactating women.
3. Complications of bleeding, perforation, pyloric obstruction, cancer.
4. Esophageal,gastrointestinal surgery history.
5. Patients can not properly express their complaints,such as psychosis, severe neurosis.
6. Taking NSIAD or alcohol abusers.
7. Allergic to penicillin or either drugs of the 6 antibiotic tested by susceptibility testing.