As the body’s cellular soldiers, white blood cells fight on the front lines against invasions by bacterial and viral threats. A number of different types of white blood cells, or WBCs, exist, each with unique strengths and disease-fighting properties. Neutrophils, for example, will swallow foreign microbes and digest them. Lymphocytes, another type of white blood cell, produce antibodies that inhibit the activity of invasive microorganisms.

Types

WBC counts can be either increased or decreased as a result of disease. An increase in WBC is called leukocytosis, while a decrease is called leukopenia, according to RNCeus. Each of these conditions causes its own set of symptoms and complications.

Leukocytosis can be caused by infections, reactions to steroid drugs or leukemia. Leukocytosis comes in five types, each named for the particular type of white blood cell that is increased.

Leukopenia is often associated with bone marrow disorders or overwhelming bacterial infections that exhaust the white blood cell supply. A variety of different types of drugs can also cause leukopenia.

Significance

Fluctuations of blood cell counts post significant risks to human health. Severely depleted white blood cell counts can indicate a situation in which the patient is at risk of contracting a serious infection that his immune system is ill-equipped to fight. Agranulocytosis, a condition wherein white blood cell count is low, is considered a serious complication of antithyroid drug therapy, according to the American Family Physician website.

Elevated white blood cell counts can be a serious cause for concern as they can result from leukemia, a potentially fatal disease.

Effects

The effects of an abnormal number of white blood cells vary according to the type of blood cells involved, and whether their levels have increased or decreased. Several types of leukemia exist, and the variety of symptoms that they can cause include fever, fatigue, swollen lymph nodes, unexplained weight loss and easy bruising, according to MayoClinic.com.

A decrease in white blood cells, as experienced in cases of agranulocytosis, can manifest with symptoms similar to leukocytosis, such as fever and weakness, along with other symptoms such as mouth ulcers and bleeding gums.

Considerations

White blood cell counts can be caused by genetically inherited disorders. Congenital agranulocytosis is passed on to children through familial abnormalities in the DNA. Mayoclinic.com notes that Down syndrome, a genetic disorder, has been linked to increased predisposition for leukemia.

Treatments

Treatment for white blood cell count abnormalities involves a number of different techniques. Chemotherapy is used as a primary form of leukemia treatment. Radiation therapy may also be helpful in destroying leukemia cells and stopping the growth of the disease. Treatment of diseases originating in the bone marrow can benefit from palliative care to address the symptoms, and stem cell transplantation to address the cause, according to the Merck Manuals Online Medical Library.