What is leukocytosis?
Leukocytosis means you have a high white blood cell count. This means you have more white blood cells than normal. Leukocytosis is a normal immune response and isn’t always a cause for concern. Most of the time, it means that your body is fighting off infection or inflammation. However, there are times when a high white blood cell count could indicate something more serious, such as leukemia.
Types of leukocytosis
There are five types of white blood cells (leukocytes), so there are five types of leukocytosis, depending on which type of cell is affected:
- Neutrophilia leukocytosis is caused by a high number of neutrophils (the most plentiful type of white blood cell, which helps resolve infections and heal damaged tissues).
- Lymphocytosis refers to high levels of lymphocytes (white blood cells that protect your lymphatic system).
- Monocytosis is caused by a high number of monocytes (white blood cells that boost your immune responses).
- Eosinophilia refers to high levels of eosinophils (white blood cells that play a role in fighting infections and inflammation). Eosinophilia is common and is often related to allergies, parasitic infections or autoimmune disorders.
- Basophilia, the rarest form of leukocytosis, is characterized by an increased number of basophils (white blood cells that play a role in fighting parasitic infections, preventing blood clotting and responding to allergic reactions).
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What does a high white blood cell count mean?
White blood cells are an important and necessary part of your immune system. Produced in your bone marrow, they defend your body against infections and disease. But, when there are too many white blood cells, it usually means you have infection or inflammation in your body. Less commonly, a high white blood cell count could indicate certain blood cancers or bone marrow disorders.
What is considered a high white blood cell count?
Typically, if there are more than 11,000 white blood cells in a microliter of your blood, it’s considered leukocytosis.
High white blood cell count during pregnancy
A high blood cell count during pregnancy is normal. Your body is simply experiencing the stress of carrying a baby. Your healthcare provider will run routine blood tests throughout your pregnancy to make sure nothing out of the ordinary is going on.
Is leukocytosis a blood cancer?
No. Leukocytosis refers to a high white blood cell count, which can occur for a number of reasons. Rarely, a high white blood cell count can be a symptom of certain blood cancers, such as acute myeloid leukemia, chronic myelogenous leukemia and chronic lymphocytic leukemia.
