H. pylori dob value of 21.9dpm indicates the presence of H. pylori infection and does not determine the severity. H. pylori dob value represents the result of carbon 13 breath test, the normal value of dob is between 0 and 4dpm, more than 4dpm indicates that there is H. pylori infection. H. pylori causes gastritis, gastric ulcers, and other digestive diseases, and has been linked to stomach cancer and lymphoma. If you are found to have H. pylori infection, even if you are temporarily asymptomatic, you should go to the hospital in time for antimicrobial treatment under the guidance of your doctor to avoid further development of adverse effects.