Modern medicine tells us that to cure gastric ulcers, duodenal ulcers and gastritis, the key is to find out if there is H. pylori infection. Once this culprit is detected in the stomach, the right treatment plan can be adopted to focus “firepower” and fight a war of annihilation. To detect the presence of H. pylori in the patient’s stomach, blood sampling, gastroscopy sampling and breath sampling are often used to detect three methods. 1, blood sampling test: that is, the use of blood sampling methods to detect the level of antibodies to H. pylori in the serum. Because the H. pylori infection, the body can produce the corresponding antibodies, so that the test results are positive, but generally takes several months and a half to be positive, so the early stage of H. pylori infection for the test, the test results often appear false negative, so that patients lose the best time for treatment. In addition, because H. pylori is eradicated even when it is. But the antibodies fall slowly, patients often need 1-2 years to turn negative, which will inevitably make the cured long-term carry the “positive” black pot and receive redundant treatment. 2, gastroscopy sampling test: patients need to do gastroscopy when the “ride” sampling, in the biopsy sampling together with the examination to detect whether there is H. pylori. If positive, a positive diagnosis of H. pylori infection can be confirmed. In order to develop an appropriate treatment plan for the patient, a culture and drug sensitivity test can sometimes be added. Gastroscopic sampling can also be followed by polymerase chain reaction testing, which is more sensitive and has more reliable results, or rapid urease testing, which is easy and fast, but the results are less reliable due to the short observation time or the influence of certain factors. Gastroscopic sampling also has the following problems: patients need to suffer from the insertion of a microscope, and if H. pylori is focally distributed, it can easily lead to a missed diagnosis (the rate of missed diagnosis is about 10%). However, with the doctor’s rich experience and proper sampling, the leakage rate can be reduced. 3, breath sampling test: the test is highly sensitive, detection rate and compliance rate is also high, the patient is painless, is one of the most popular methods of detection of H. pylori in recent years. Specific methods can be divided into two: 14C breath test and 13C breath test. The 14C breath test is less expensive (generally $120), but should be used with caution in children, pregnant women, nursing mothers, and the elderly and infirm due to the radiation hazard of the test, and it is also advisable to avoid repeated use of this method for the same patient. 13C breath test is non-radioactive, harmless, and has a higher detection and compliance rate (nearly 100%), and can be used by patients of all ages. Patients of all ages can use this method, and its cost is generally 200 yuan. The test requires the patient to fast for three hours before the test, and during the sampling process, the patient takes a capsule within half an hour and exhales three times to retain the sample, which can detect the presence of H. pylori infection very accurately. 13C breath test has been recognized as the best method to detect H. pylori at present.