A white blood cell (WBC) count is considered high, or leukocytosis, when it exceeds 11,000/μL in adults. Similarly, a low WBC count (leukopenia) is dangerous because it increases the risk of infections. The danger level isn't solely determined by the number itself but also by the cause of the elevated or decreased count. A high WBC count might indicate an infection, blood cancer, or other underlying medical condition. Conversely, a low WBC count can result from certain medical treatments like chemotherapy or bone marrow disorders.
Understanding High WBC Counts
A high WBC count (leukocytosis) exceeding 11,000/μL is generally considered high and warrants investigation to determine the underlying cause. This elevated count often signals that the immune system is actively fighting an infection or dealing with another health problem. Examples of conditions that can cause high WBC counts include:
- Infections: Bacterial, viral, or fungal infections.
- Blood cancers: Leukemia, lymphoma.
- Inflammatory conditions: Rheumatoid arthritis, inflammatory bowel disease.
- Stress: Severe physical or emotional stress can temporarily raise WBC levels.
Understanding Low WBC Counts
A low WBC count (leukopenia) signifies that the body isn't producing enough white blood cells to fight off infections effectively. This leaves the individual vulnerable to various illnesses. The causes of low WBC counts include:
- Bone marrow disorders: Conditions affecting bone marrow's ability to produce WBCs.
- Autoimmune diseases: Conditions where the immune system attacks healthy cells.
- Certain medications: Chemotherapy and other medications can suppress WBC production.
- Viral infections: Some viruses can temporarily decrease WBC counts.
- Nutritional deficiencies: A lack of essential nutrients can also impact WBC production.
It's crucial to consult a doctor to determine the cause of an unusually high or low WBC count. Treatment will depend on the underlying condition. The number itself isn't the only indicator; the doctor will consider a complete blood count (CBC) and other relevant factors for accurate diagnosis and management. Further investigation often involves additional tests such as blood smears and bone marrow biopsies. Longitudinal studies also show that dangerous WBC counts are linked to a higher risk of heart disease, although this requires further research and deeper understanding.
