Disorders That Attack the Immune System

Some of the most devastating disorders that can affect the human race are those that attack the very defense system we have against diseases, our immune system. These disorders can vary in severity from causing small rashes or a stuffy nose, to attacking vital organs throughout the body, causing death. They can also come from a variety of sources from the genetic passing down of traits, to infection from a disease. These immune system disorders fall under four categories: immunodeficiency, autoimmune, allergic and cancer.

The Immune System

• Before we can understand the types of disorders that attack the immune system, we must first understand how the immune system works. The immune system is the body's natural defense system against invading bacteria, viruses and other substances that can have a negative effect on the body. These substances are called antigens. When an antigen enters the body, the body reacts with an immune response. The immune response causes the body to produce leukocytes, which in turn speed through the body to the source of infection and neutralize or kill the antigen. These leukocytes are made and stored in organs throughout the body, including bone marrow, thymus and spleen. There are two types of leukocytes, phagocytes and lymphocytes. The phagocyte works by chewing up its target. The lymphocytes also help to attack an invader, but they also create an immunity. This means that the lymphocyte cells record the invader for future reference, in order to mount a quicker response the next time it tries to invade. The immune system works much like a machine. Each part is important to mounting a successful assault on any foreign invader trying to gain access to the body.

Immunodeficiency Disorders

• An immunodeficiency disorder is one of the many disorders that attack the immune system. In these disorders the immune system has problems that cause the system to not work correctly. Many times this is due to a genetic trait or birth defect. These disorders are usually caused by missing pieces of the immune system, or pieces of the immune system not working the way they are supposed to. The most common immunodeficiency disorders are severe combined immunodeficiency (SCID), also known as "bubble boy" disorder, DiGeorge syndrome, and IgA deficiency. Immunodeficiency disorders may also be acquired, either by the contraction of a disease, or exposure to pharmaceuticals. The most common types of acquired immunodeficiency disorders are HIV/AIDS, and suppressed immune systems due to medications such as chemotherapy drugs.

Autoimmune Disorders

• Autoimmune disorders attack the immune system by tricking the body into thinking its own organs are foreign invaders. When this happens, the phagocytes and lymphocytes turn on healthy tissues and organs and destroy them. Common autoimmune diseases are lupus, scleroderma, juvenile dermatomyositis and juvenile rheumatoid arthritis. The severity of an autoimmune disorder can vary dramatically. Some may only cause localized swelling and inflammation by attacking the tissue in the joints, while others may cause death by attacking vital organs.

Allergic Disorders

• Allergic disorders are another common problem that attacks the immune system. An allergic disorder is an issue in which the body overreacts to an antigen in the surrounding area, such as in the air. These are more commonly known as allergens. When exposed to the allergen, the body's immune system overreacts by causing small symptoms such as watery eyes or a stuffy nose, to deadly anaphylaxis. The most common allergic immune disorders are asthma, allergies and eczema.

Cancer

• Outside of the AIDS virus, certain types of cancer can be the most devastating of disorders that attack the immune system. Cancer can target any cells in the body. This includes the cells involving the immune system. The most common forms of immune system-attacking cancer are lymphoma and leukemia. Lymphoma is formed when the cancer targets the lymphoid tissue, while in leukemia the cancer affects the leukocyte cells. Both are more commonly found in children than adults.