The common causes of high white blood cells found in routine blood tests include: 1. Physiological factors, commonly seen during menstruation, strenuous exercise, emotional stress, satiety, and showering, can increase the white blood cell count. This condition does not need to be treated with medication, and the white blood cells can drop to normal on their own. 2. Consider the presence of infection, as bacterial and viral infections can also cause elevated white blood cells. This condition is often accompanied by fever, sore throat, cough, coughing, frequent urination, urinary urgency, painful urination and other symptoms of various system infections. 3, seen in blood system diseases, such as acute leukemia, chronic leukemia, early stage of myelofibrosis, will also appear increased white blood cell count. For this type of disease, systematic tests such as bone marrow aspiration, flow cytometry, and bone marrow biopsy are required to confirm the diagnosis.