Elevated leukocytes and neutrophils may be caused by infections or the body’s reaction under stress. 1. Infections: especially bacterial infections, often secondary to leukocyte and neutrophil elevation, such as bacterial pneumonia, bacillary dysentery, in the pathological examination of neutrophil infiltration can also lead to localized septic infection. 2. Response to stress: for example, in severe trauma, burns and other situations, the body will enter a state of stress, this situation will agitate the storage in the spleen in the mononuclear phagocytosis system, in which leukocytes will be rapidly released into the blood, resulting in a rapid increase in white blood cells and neutrophils. There are other reasons for elevated white blood cells and neutrophils, such as rheumatic immune diseases, acute granulocytic leukemia, etc., all of which can lead to elevated white blood cells and neutrophils, and the cause should be clarified in time for targeted treatment.