White blood cells also called leukocytes are like soldiers that defend our body against infectious organisms like bacteria, viruses, and other toxins. They are produced in bone marrow — the spongy tissue inside some of the larger bones. Although these cells are practically on-duty all the time, but in case of sudden attack by enemies in large numbers, they are alerted and plunge into action resulting in increased numbers.
An elevated WBC count may be present in conditions such as:
- Acute or chronic lymphocytic leukemia (cancer of the lymph nodes)
- Allergic infections such as cold, cough from dust, pollen, particulate matter
- Certain medications such as corticosteroids
- Bacterial or viral infections
- Arthritis, rheumatoid
- Smoking since it causes inflammation in the body
- Stress
- Respiratory infections such as tuberculosis or whooping cough
Low WBC counts may occur:
- Anemia, aplastic
- Anti-cancer therapies such as chemotherapy or radiation
- Certain congenital disorders involving impairment in action of neutrophils
- Malnutrition
What is normal?
Normal : 4,500 to 11,000 WBC/ mcL
Abnormal : >11,000 WBC/ mcL
So basically a high WBC count in the CBC reports indicates that body’s defense system is at work . In a way it is a good sign indicating that body is efficient in self-defense. Once the enemies are dealt with , the system takes some rest and return to work as normal.
References:
http://www.mayoclinic.org/symptoms/low-white-blood-cell-count/basics/causes/sym-20050615
http://www.mayoclinic.org/symptoms/high-white-blood-cell-count/basics/definition/sym-20050611