The sensitivity and specificity of the H. pylori gas test for detecting H. pylori is higher than that of a blood test and may give more accurate results. 1. Urea breath test: It is a commonly used test to diagnose H. pylori infection and to determine whether a patient has H. pylori infection. Urea breath test can reflect active H. pylori infection and help to assess clinical efficacy, which is widely used in clinical practice. However, due to recent use of antibiotics or proton pump inhibitors, a false-negative result can occur with the urea breath test. Therefore, the test must be discontinued for at least 4 weeks for antibiotics and bismuth and 2 weeks for proton pump inhibitors. 2. Hematology: It can help the doctor determine whether the patient has H. pylori infection, but it does not necessarily mean that the infection is occurring. Since the qualitative antibody test result is always positive 3 years after successful treatment of H. pylori, and the quantitative antibody test level does not decrease significantly 6 to 12 months after treatment, this test cannot be used to evaluate the effectiveness of treatment. If H. pylori infection is suspected, it is recommended to consult a doctor in time, improve relevant examinations, make a clear diagnosis, and carry out targeted treatment or therapy under the guidance of a doctor.