White blood cells, or WBC, are produced in the bone marrow and are the disease-fighting cells of the body. According to MedLinePlus, a low WBC count, also called leukopenia or neutropenia, is when the concentration of white blood cells in the body are less than 4,500 cells per microliter of blood. There are five kinds of white blood cells—neutrophils, lymphocytes, monocytes, eosinophils and basophils—but leukopenia generally refers to low neutrophils, the white blood cells that fight bacterial infections. MayoClinic.com lists several causes of leukopenia: bone marrow failure from infection, tumor invasion or scarring, autoimmune diseases such as lupus, toxic exposure including drugs and radiation, diseases of liver or spleen, and overwhelming infection. Treatment of leukopenia is based on the underlying cause, severity and presence of associated infection.
Removal of Agents & Addition of Vitamins
Removal of possible causative agents such as drugs or toxins often is all that is required to restore a white blood cell count to normal, according to the The Merck Manual. Other initial measures include treating underlying vitamin deficiencies, including B-12 and folate, as well as infectious etiologies. Since infection is the main concern with neutropenia, careful hand washing and avoidance of sick contacts is important.
WBC Growth Factors
An article in the September 2006 issue of Annals of Oncology reports that using medications that stimulate the bone marrow to produce white blood cells is a mainstay of leukopenia treatment. The two most widely used so-called growth factors are Neupogen and Neulasta. These drugs are given as an injection and are effective in increasing WBC levels. However, they should be used with great caution in patients with sickle cell disorder, abnormalities in red blood cells, myelodysplasia and chronic myeloid leukemia. When using WBC growth factors, prompt medical care should be sought for symptoms of sudden abdominal pain, shortness of breath or signs of infection. Steroids may be used for immune-mediated leukopenia and function by redistributing existing white blood cells so they can be better utilized.
To prevent infections with leukopenia, antibiotics are often used, though there is a concern for the development of drug-resistant bacteria. The Merck Manual lists Bactrim as a commonly used prophylactic antibiotic, but adverse side effects may result. There are now studies supporting the effective use of levofloxacin in preventing serious bacterial infections in leukopenic patients. Less data is available for the prophylactic use of anti-viral and anti-fungal drugs but should be considered in severe leukopenia.