According to the sources, a normal white blood cell count is generally about 4,500 to 11,000/μL. A high white blood cell count, called leukocytosis, is generally diagnosed when white blood cell levels exceed 11,000/μL. A count of more than 11,000 white blood cells in a microliter of blood is considered high. A low white blood cell count, called leucopenia, is generally diagnosed when white blood cell levels are below 4,500/μL. An adult who has fewer than 1,000 neutrophils in a microliter of blood has neutropenia. If the neutrophil count is very low, fewer than 500 neutrophils in a microliter of blood, it is called severe neutropenia.
It is important to note that a high or low white blood cell count may be dangerous, depending on the cause. A high white blood cell count can indicate a range of health problems such as infection or a blood or bone marrow disorder. A low white blood cell count can make it harder for the body to fight off infection, and a person is more likely to get sick.
It is recommended to ask for your white blood cell count and specifically, your neutrophil count when your blood is tested. If your counts are low, it is important to take measures to prevent infections. If there is no clear reason for a low white blood cell count, your doctor will probably want to do the test again or do a differential or "diff" along with the CBC to give more detail.
