High white blood cells are the result of routine blood tests performed by the patient, which may be a sign of inflammatory conditions such as appendicitis and gastroenteritis, or may be caused by blood system diseases such as leukemia. 1. Appendicitis: appendicitis can lead to high white blood cell counts, and the patient will have lower right abdominal pain, anorexia, nausea, diarrhea and other symptoms. 2. Gastroenteritis: Gastroenteritis will also have the manifestation of elevated white blood cells, gastroenteritis is mainly caused by bacterial, viral, fungal and other pathogenic infections, the patient’s main symptoms are diarrhea, epigastric pain, abdominal distension, eructation and so on. 3. Leukemia: leukemia is a non-infectious disease, the cause of which is not clear at present, and it is considered to be caused by biological, physical, chemical and other factors, which will lead to the elevation of white blood cells of patients, and also lead to the emergence of high fever, anemia, hemorrhage and other symptoms. When patients have elevated white blood cells, it may also be caused by bronchitis, tonsillitis and other diseases. The patient should consult a doctor in time to identify the cause of the disease and follow the doctor’s instructions.