A blood test for H. pylori 50 is positive for H. pylori antibodies, suggesting a previous or current H. pylori infection. However, most clinical tests for H. pylori are more commonly performed with a breath test. The next step in the diagnostic and therapeutic program should be in accordance with medical advice. 1. There are many kinds of tests for H. pylori, including H. pylori antibody test, gastroscopic pathologic examination, carbon 13 or carbon 14 breath test and so on. H. pylori antibody test is a preliminary screening test, and a positive test does not necessarily mean infection. 2. If H. pylori is infected in the past and the antibody is positive, the patient usually has a history of stomach discomfort, such as acid reflux, stomach pain, heartburn, etc., and some patients may be asymptomatic. 3. If currently infected with H. pylori and antibody-positive, most patients will have a history of gastric discomfort, such as nausea, acid reflux, heartburn, and stomach pain. It is also necessary to do a breath test, gastroscopy, etc. to further clarify whether there is gastritis and the severity of gastritis. It is recommended to consult a doctor for further investigation.