Inclusion Criteria:  Gastroscopy can be performed H. pylori test and pathological analysis can be performed  Exclusion Criteria:  Age < 20 or > 80 years Anemia (serum hemoglobin level < 10 g/dL) Severe systemic disease Advanced chronic liver disease Use of certain medications, including proton pump inhibitors, H2- receptor antagonists, or antibiotics History of H. pylori eradication History of gastric surgery Recent history of upper gastrointestinal bleeding