DISORDERS OF THE IMMUNE SYSTEM
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Do you suffer from any form of allergy? If so, what causes the allergy? What are the symptoms?
Types of immune system disorders
When the immune system, which protects the body against infection and harmful invaders, does not work properly, it causes an immune system disorder. There are many different types of immune system disorders, including immunodeficiency diseases, autoimmune disorders and allergic disorders.
Immunodeficiency disorders
They cause a weakening of the immune system, allowing infections and other health problems to occur more easily. Primary immunodeficiencies (also called primary immune disorders) are those you are born with. They are the result of genetic defects and most of them are inherited. Secondary immunodeficiencies (also called acquired immunodeficiency) occur when the immune system is compromised due to an environmental factor or by a disease (HIV/AIDS, chemotherapy, malnutrition).
AIDS (Acquired Immune Deficiency Syndrome) is a very serious disorder which may happen when the immune system has been severely damaged. It is caused by HIV (Human Immunodeficiency Virus) which destroys T-cells until the immune system is unable to fight off even minor illnesses. The three stages of HIV infection are: (1) acute HIV infection, (2) chronic HIV infection and (3) AIDS.
Autoimmune diseases
Sometimes the immune system’s recognition apparatus breaks down, and the body begins to manufacture antibodies and T-cells directed against the body’s own cells and organs. Such cells and autoantibodies contribute to many diseases which can affect almost any part of your body. For instance, T-cells that attack pancreas cells contribute to diabetes, while an autoantibody known as rheumatoid factor is common in people with rheumatoid arthritis.
Allergic disorders
Allergic disorders1 are caused by an overactive immune system which reacts to substances in the environment that are normally harmless. These substances are called allergens1. Some conditions caused by an overactive immune system are: asthma, allergic rhinitis, eczema – with symptoms such as wheezing, sneezing, red eyes, an itchy rash, coughing, a runny nose, shortness of breath, or swelling. Allergens may be dust, grass and tree pollen, food – particularly nuts, fruit, shellfish, eggs and cows’ milk – insect bites and medicines.
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1 The number of people with allergies is increasing every year. The reasons for this are not understood, but is probably the result of living in a cleaner, germ-free environment in much of the world, which reduces the number of germs our immune system has to deal
with.
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1 Substances that cause allergic reactions are called allergens. Do you know the most common ones?