The body has several types of white blood cells that are all responsible for fighting infection and foreign invaders. According to Medline Plus, there are five major types of white blood cells: basophils, eosinophils, lymphocytes, monocytes and neutrophils. Anytime the body has difficulty producing these defenders due to an underlying condition, it becomes vulnerable to infection.
Neutropenia
Neutropenia is a condition in which the immune system does not produce enough neutrophils--white blood cells that protect the body from fungal and bacterial infections. According to Mayoclinic.com, 45 to 70 percent of the white blood cells are neutrophils. Neutropenia can be caused by viral infections, disorders that affect the bone marrow, or drug treatment. In order to treat neutropenia, it is necessary to first diagnose the underlying condition that is causing it.
Aplastic Anemia
According to Mayoclinic.com, aplastic anemia is a disease that occurs when the body stops producing enough new blood cells. Aplastic anemia causes fatigue, increases the risk of developing infections and can lead to uncontrolled bleeding. Aplastic anemia occurs when damage is done to the bone marrow. This damage slows the production of new blood cells including red cells, white cells and platelets. The cause of this damage can come from radiation therapy, autoimmune disorders, a viral infection or exposure to toxic chemicals. Treatment for aplastic anemia includes blood transfusions, bone marrow transplants and antiviral or antibiotic medication.
HIV/AIDS
According to the University of Maryland Medical Center, HIV is a disease that slowly destroys the body’s immune system, making it harder to fight infections. With a normal immune system, antibodies and white blood cells fight and destroy foreign invaders that enter the body. This response is controlled by white blood cells called CD4 lymphocytes. These cells are also the main targets of HIV. HIV attaches to these cells and enters them. Once HIV is inside these cells, the virus injects its own genetic material into the them and makes copies of itself. Eventually the number of CD4 cells drops due to invasion and the body's immune system becomes vulnerable to infection.
Lupus
According to the University of Maryland Medical Center, lupus is an inflammatory autoimmune disorder. With lupus, the body's immune system can attack its own tissue. Lupus can also reduce the amount of white blood cells. Symptoms of lupus include fatigue, fever, weight loss and body pain. Treatment for lupus includes the use of nonsteroidal anti-inflammatory drugs, corticosteroids and antimalarial drugs.
Leukemia
According to Mayoclinic.com, leukemia is a cancer that affects the blood-forming tissues in the body. These tissues include the lymphatic system and the bone marrow. Leukemia usually starts off affecting the white blood cells. With leukemia, the bone marrow produces a high amount of abnormal white blood cells. These white blood cells do not function properly, and consequently make it difficult for the body to fight off infection. The cause of leukemia seems to be related to genetic and environmental factors. Symptoms of leukemia--depending on the type--include fever or chills, persistent fatigue and frequent infections. Other symptoms commonly reported are losing weight without trying and easy bleeding or bruising. According to Mayoclinic.com, some forms of treatment can include chemotherapy, radiation therapy, biological therapy and stem-cell transplant.
