Immune Diseases: Major Types

Instructor: Sarah Friedl

Sarah has two Master's, one in Zoology and one in GIS, a Bachelor's in Biology, and has taught college level Physical Science and Biology.

Your immune system is designed to protect you from foreign invaders. But sometimes the immune system is weakened or overactive, leading to a wide range of problems in the body.

The body
immune system

Because this bombardment is fairly constant, your immune system is always on alert. It works around the clock to fight anything it thinks might be trying to harm you. When it's operating properly, your immune system is strong because it is made up of all different cells, tissues, glands, and organs. But when one or more parts of your immune system fail, so does your army, which puts your basic health at risk.

Immunodeficiency Diseases

While some immune system problems arise later in life, some people are born with inadequate immune systems. We call these primary immunodeficiency diseases because the normal immune response is deficient (or simply not present) from birth. People who have immunodeficiency diseases are often sick because their bodies are susceptible to many different diseases and infections.

Even simple bacteria infections can lead to serious problems for a deficient immune system

Deficient immune systems can also develop later in life due to secondary immunodeficiency diseases. Instead of being born with a weakened, or deficient, immune system, you develop one later in life, sometimes from an external source. AIDS and lymphoma cancers are examples of these diseases. If you have a secondary immunodeficiency disease, you will likely become sick with other diseases, such as pneumonia. You will also be more vulnerable to minor infections.

Autoimmune Diseases

Sometimes, instead of having a deficient immune system, you will have one that works too hard and turns the body against itself. We call this an autoimmune disease. These are things such as lupus, rheumatoid arthritis, Crohn's disease, and multiple sclerosis. So you can remember that an immunodeficiency is when the immune system is deficient, and an autoimmune disease is when the normal immune system autopilot takes on a life of its own!

In the case of an autoimmune disease, instead of fighting off intruders, the immune system starts fighting the body itself as if it were a foreign intruder. The damage this causes can lead to joint inflammation, arthritis, muscular dysfunction, kidney malfunction, and even paralysis.

However, autoimmune diseases do not affect everyone the same way, and some only affect select groups of people. Women are 2-3 times more likely to develop rheumatoid arthritis and multiple sclerosis than men, and they are also 9 times more likely to develop lupus. Other factors that influence who develops an autoimmune disease are genetics and the environment. High stress levels can also disrupt the ability of the immune system to function normally.

Autoimmune diseases may be treated with immunosuppressant drugs, which help to suppress an immune system that has gone haywire. But there is a trade-off here, since suppressing your immune system also suppresses your defense against infection and disease.

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