wbc refers to white blood cell count. There are many reasons for elevated white blood cell count, which is commonly caused by infections such as purulent tonsillitis, pneumonia and other diseases such as leukemia. 1. Purulent tonsillitis: When the body resistance drops, bacteria or viruses present around the pharynx multiply and invade the tonsillar tissue, resulting in congestion, swelling and suppuration. Blood routine shows elevated white blood cell count and neutrophil percentage. 2. Pneumonia: It is an infection of the lungs caused by bacteria, viruses or other pathogens. Bacterial pneumonia may show elevated white blood cell count and elevated neutrophil count and percentage. 3. Leukemia: due to the malignant hematopoiesis of bone marrow leading to the production of a large number of clonal antibodies by primitive and naïve white blood cells, routine blood tests show elevated white blood cell counts. However, not all leukemia patients will have elevated white blood cell counts, but may also have normal or lowered white blood cell counts. There may be other reasons for elevated white blood cell counts, such as severe burns, acute bleeding, poisoning, etc., which should be promptly examined to determine the cause of the disease and standardized treatment under the guidance of a doctor.