When the Defenders Go Awry: Understanding the Inner Workings of Allergies, Autoimmune Disorders, Cancer and Sepsis

This is the second post in a two part series on the immune system, to learn how a healthy immune system works check out Part 1 (Your Body’s Defenders).

There are many parts of our body that we take for granted until they are not functioning correctly and the immune system is no exception! The first time our family got sick at the same time after having our second baby my husband and I were not ready for that level of co-misery haha! Thankfully most sicknesses clear up quickly thanks to our amazing immune system working properly. But other times the immune system is having more serious problems like an autoimmune disease where it actually starts attacking healthy cells.

The “Common” Cold

*Insert the toddler parent’s eye roll* Whoever came up with the term “common” knew what they were saying! Did you know that a cold is actually a virus? This means that antibiotics will not help a person who has a cold because antibiotics work against bacteria, not a virus. With sicknesses like the cold and flu the body’s immune system is actually working properly. It has detected a foreign invader and is doing the work to get rid of it.

Now that we recognize that just because we feel miserable doesn’t mean our immune system isn’t doing its job, lets jump in to learning about what is happening when our immune system is actually not working.

Allergies

Did you know that allergies are the result of your immune system being too active? In a person with an allergy their immune system mistakenly recognizes something harmless as harmful for the body and attacks it. For example, when a person has asthma their immune system overreacts to triggers in their environment such as dust. This causes an immune response in the tubes that bring air into the part of their lungs where the oxygen and carbon dioxide exchange occurs. The allergic reaction leads to their airway becoming narrow due to both the muscles tightening and inflammation.

Autoimmune Disorder

An autoimmune disorder occurs when a person’s immune system mistakenly attacks healthy parts of their body. This can make it extremely hard for your body to function correctly. The way that this affects the person’s life depends on what part of their body their immune system is attacking.

Below we will cover an overview of some common autoimmune disorders (this is by no means a complete list of the many disorders that can occur):

Infectious Diseases that Attack the Immune System

Human Immunodeficiency Virus or HIV is a virus that attacks a person’s immune system. It does this by attacking the T cells. The T cells are a part of your immune system that helps to fight off infections. This is why as the disease progresses a person with HIV easily becomes sick as their immune system is severely weakened. This is not all that HIV does though. HIV is a type of virus called a retrovirus. This means that not only does it destroy a person’s T cells but it also changes the “code” of the person’s cells to cause them to create more of the human immunodeficiency virus. Once HIV has destroyed enough of the person’s immune system the disease has progressed to Acquired Immune Deficiency Syndrome or AIDS. This means that the person’s immune system has become so weak that they become easily sick from infections or cancers that don’t normally cause problems for people.

Cancer

Cancers and cancer treatments closely affect your immune system. To better understand how, we will discuss three types of cancers next: leukemia, lymphoma and myeloma. To put it plainly, these are blood cancers.

Sepsis

You may have heard the term sepsis and know that it is serious but what actually causes it? Sepsis is a very serious condition that can occur when a person has an infection. When a person develops sepsis it is because their body has had an infection and their body is no longer responding correctly to the infection and begins to attack it’s own cells and organs. This is a medical emergency and needs to be addressed right away. Sepsis begins a cascade of events within the body that will likely lead to organ failure and death if untreated. This cascade has multiple pathways that cause inflammation throughout the whole body, cause blood clots to form and cause what is termed “leaky blood vessels.” All of this adds up to the person’s organs not receiving an adequate amount of blood supply with oxygen and nutrients that leads to organ damage and ultimately failure.