The diagnosis of gastroenteritis can not be detected by blood sampling, gastroenteritis is mainly based on the following aspects: First, the patient’s clinical manifestations are abdominal pain, diarrhea or watery stools, nausea, vomiting and occasionally dizziness, fever and other symptoms. Second, the abdominal examination bowel sounds are active. The third, stool routine examination appears white blood cells, red blood cells or even pus and blood stool, and blood sampling blood routine can only indicate the severity of the infection, if the white blood cells rise significantly, it indicates that the intestinal infection is often more serious, at this time need to consider the use of antibiotics, but if the white blood cell level is not high, it is not necessarily necessary to use antibiotics.