An upset stomach is usually a condition such as stomach pain and bloating. And C-reactive protein is a non-specific inflammatory tumor marker. C-reactive protein is a major indicator of inflammation and infection, and also has the effect of activating complement and clearing damaged and necrotic tissues. When c-reactive protein is high, it may be a tumor or inflammation that causes stomach discomfort, so measuring c-reactive protein helps doctors determine the category of the disease, and when c-reactive protein is low, it means that the patient does not have tumor or inflammation that causes stomach pain or bloating. And when c-reactive protein is low, it means that the patient is not suffering from stomach discomfort caused by tumor or inflammation, which is conducive to subsequent treatment. Stomach discomfort can be determined by the range of c-reactive protein value to determine the disease, of course, the value of c-reactive protein is also susceptible to other factors, so the stomach discomfort can be measured by the c-reactive protein, but it is not the only indicator of the test, but also need a variety of other tests to cooperate, in order to determine the disease.