Illnesses of the Immune System Allergies Allergies when

Illnesses of the Immune System

Allergies Allergies- when the immune system reacts to harmless antigens (allergens) such as pet dander, pollen, or dust. This triggers the inflammatory response, causing sneezing, watery, itchy eyes, etc. Antihistamines can counteract these symptoms. Allergic reactions in the respiratory system can create asthma.

Autoimmune diseases Autoimmune diseases- when the immune system attacks the body’s own cells. Examples include Type 1 Diabetes, in which insulin-producing cells of the pancreas are attacked, causing increased or erratic blood sugar levels, and also lupus, in which the immune system makes antibodies that attack a person’s own proteins.

Type 1 Diabetes Type 2 Diabetes

HIV and AIDS HIV and AIDS- HIV is a virus that attacks key cells within the immune system (helper T cells, mostly), leaving the body with inadequate protection against pathogens. When an HIVinfected person’s T cell count reaches about 1/6 th the normal level, he or she is diagnosed with acquired immunodeficiency syndrome (AIDS).

Leukemia Leukemia- a group of cancers that affect the bone marrow and the blood cells made in the bone marrow. Remember, cancer Is caused by mutations in genes that control the cell cycle, leading to unchecked cell division. Chronic leukemia causes a high number of abnormal white blood cells to be made, resulting in an inadequate ability to fight pathogens. Leukemia can also affect blood platelets and red blood cells, which can cause excessive bleeding and anemia.