White blood cells, also called leukocytes, are an important part of our immune system that play a vital role in defending the body from various infections. There are different types of white blood cells; neutrophils, lymphocytes, monocytes, eosinophils, and basophils. All of them are produced in the bone marrow and are found in the lymph tissues and blood. Neutrophils, eosinophils and basophils are called granulocytes. T cells, B cells and natural killer cells are types of lymphocytes. There is a definite life span of these cells; it can be 2 weeks to 3 weeks, after which they are destroyed. The number of leukocytes present in the body changes with advancing age.

Increase or decrease in the number of leukocytes in the blood, leads to different diseases and disorders of the white blood cells. Neutropenia, HIV/AIDS and lymphocytopenia are caused due to low white blood cell count, while leukemia is caused due to high white blood cell count. Given below is a brief information on these diseases and disorders.

Neutropenia: Neutrophils contribute to 70% of white blood cells in our body. They help the body fight against pathogens. Neutropenia is caused due to reduced number of neutrophils in the blood. There are several causes of neutropenia. Side effects of any medication, chemotherapy, and viral infection are some of the causes. Inadequate formation of neutrophils in the bone marrow or destruction of neutrophils in the bloodstream, can cause a type of neutropenia called autoimmune neutropenia. Fever or any frequent infection can be symptoms of neutropenia. Neutropenia is diagnosed by determining the white blood cell count. Normal neutrophil count is 3000 to 8000 (per microliter of blood). Neutropenia is diagnosed when the neutrophil count is below 2000. The treatment for neutropenia depends on the cause. Medications that can help increase the number of neutrophils are recommended to such patients. In rare cases, bone marrow transplant is performed.

HIV/AIDS: AIDS is a life-threatening disease that is caused due to the Human immunodeficiency virus (HIV). The final stage of this infection is called AIDS (Acquired Immunodeficiency Syndrome). This virus attacks and destroys the white blood cells, that are responsible for regulating the immune system. Thus, the immune system of an infected person becomes very weak. The HIV can pass to others through person-to-person contact. Thus, unprotected sex with a HIV-infected person is the most common cause. An infected mother can pass the virus to her child. These days, the infection to the child can be prevented with the help of proper treatment. HIV does not show any symptoms in its early stages. Neither is there any vaccine that can prevent HIV infection nor any treatment that can cure it. Safety measures are the only way to avoid getting infected with HIV.

Lymphocytopenia: Reduced number of lymphocytes in the blood leads to lymphocytopenia. Chronic infections and hereditary disorders are some of the causes of the disease. The treatment is given depending upon the cause.

Leukemia: Leukemia, also called blood cancer, is a group of diseases that is caused due to uncontrolled and abnormal increase of immature leukocytes. The bone marrow produces a large number of immature white blood cells. Lymphocytic leukemia is caused due to increased number of lymphocytes. The reason behind the uncontrolled growth in the number of immature cells is still unknown. The following is a list of different types of leukemia that occur due to increase in the number of immature white blood cells:
  • Acute myeloid leukemia (AML)
  • Chronic myeloid leukemia (CML)
  • Acute lymphocytic leukemia (ALL)
  • Chronic lymphocytic leukemia (CLL)
Leukemia patients are susceptible to any kind of infection. Their immune system is not capable of fighting against infection. Chemotherapy and bone marrow transplant are some of the treatments given for leukemia.

Eosinophilia, monocyte disorders, idiopathic hypereosinophilic syndrome are some other diseases related to white blood cells. Leukocytes are vital cells of our body, and diseases and disorders associated with the WBCs can lead to serious problems. Treatment coupled with lifestyle changes can help to normalize white blood cell count, which in turn, will lower the risk of infections in the future.

Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.