What Is Being Immunocompromised?

Some people are at a much higher risk of severe complications from viral, bacterial, or fungal infections than others. Typically, those include older adults and people who are immunocompromised.

But what does it mean to be immunocompromised, exactly? Here's what you need to know about how your immune system affects your risk of getting and developing complications from infections.

What Does Being Immunocompromised Mean?

When a person is immunocompromised, also called immunosuppressed or immunodeficient, their immune defenses are weak, William Li, MD, author of Eat To Beat Disease: The New Science of How Your Body Can Heal Itself, told Health. 

Many body parts make up your immune system, including:

• Bone marrow
• Lymph nodes
• Thymus
• Tonsils
• Parts of the spleen and gastrointestinal (GI) tract
• Parts of your blood, such as antibodies and white blood cells

"These defenses, made of an army of cells with unique weapons that destroy invaders in the body, protect you against the common cold, bacteria, and viruses, and even cancer," explained Dr. Li. "When the defenses are low, an individual becomes highly vulnerable to infection."

"[Being immunocompromised] also can involve many different aspects of our body's defense system, such as a lack of white blood cells that phagocytose and kill microbes, or problems making adequate antibodies in response to exposure to foreign organisms," Melinda Ring, MD, executive director of the Osher Center for Integrative Health at Northwestern University, told Health.

Phagocytes are immune cells that kill invaders, like bacteria and viruses, by ingesting them.

Common Causes of Immune Deficiency

Your immune system has several body parts and cell types that work together to protect you. However, if you're immunocompromised, one or more of those parts may not work correctly. As a result, your immune system doesn't work as efficiently as usual.

Being immunocompromised can be temporary or permanent, depending on the underlying cause. There are two types of immune deficiency, both of which are caused by many reasons.

Primary Immunodeficiency

Typically, primary immunodeficiency is present at birth. In that case, immunocompromised people may have a hereditary disorder or disease. The symptoms usually appear in infancy or early childhood.

There are over 200 primary immunodeficiency disorders, many of which are rare and don't have a cure. Almost all primary immunodeficiency disorders affect the immune system, leading to abnormal or insufficient immune cells and antibodies.

Some primary immunodeficiency disorders include:

• Hyper IgM syndromes
• Severe combined immunodeficiency (SCID)
• Chronic granulomatous disease (CGD)
• Interferon gamma, interleukin 12 and interleukin 23 deficiencies
• X-linked agammaglobulinemia (XLA)
  

Secondary Immunodeficiency

Medication or treatment for a disease or chronic illness causes secondary immunodeficiency. Some common examples include:

• Chronic conditions that affect the immune system, like heart disease, lung disease, lupus, cancer, and diabetes
• Acquired disorders, like human immunodeficiency virus (HIV), which attacks your immune system, malnutrition, and spleen removal
• Medications like chemotherapy, steroids, and post-transplant anti-rejection medicine

Anti-rejection medicines suppress the body's ability to activate its defenses by destroying immune cells or blunting the cell's ability to spot and kill bacteria, explained Dr. Li.

Immune Deficiency Symptoms

Often, symptoms of being immunocompromised include:

• Having frequent bacterial infections, like pneumonias
• Having different infections happening one after another, especially ones that become more and more severe
• Taking longer than most people to recover from an infection
• Not responding well to medications or treatments
• Getting infections from germs that usually don't cause severe illnesses

If you have frequent or severe infections, contact a healthcare provider.

Dangers of Being Immunocompromised

There are different levels of immune deficiency. For example, some people may have a higher risk of certain viral or fungal infections than others but respond to treatment. Others may have severe symptoms or infections that last longer than normal.

In contrast, "some people are at ongoing high risk, in which case exposure to infection needs to be aggressively avoided," explained Dr. Ring. "These individuals are more susceptible to unusual pathogens and even common infections like pneumonia can become life-threatening."

You May Not Have an Immune Reaction When Needed

You're more at risk of infections if you're immunocompromised than others. Your immune system may not mount the usual obvious reactions to threats, such as a fever or swelling.

"This can lead to infections being missed early on and allow them to become more deeply seated in the body before a person realizes there is a need to seek help from a [healthcare provider]," said Dr. Ring.

Also, you may lack the ability to respond appropriately to vaccines. For example, you may not develop immunity and mistakenly assume a vaccine will protect you against an illness.

"When the immune system isn't working at full capacity, it doesn't have the army of immune cells and mediators ready to mount a defense at the first sign of attack," said Dr. Ring. "This means infections may progress more rapidly from a mild virus into sepsis, a widespread infection leading to malfunction of the body's organs."

Precautions To Take if You're Immunocompromised

If you're immunocompromised, be careful not to weaken your immune system further.

"Emotional stress, lack of sleep, and physical exhaustion can all depress immunity, making an immunocompromised patient more susceptible to disease," explained Dr. Li. Additionally, a healthy diet consisting of foods supporting immunity is key.

In general, some other precautions include:

• Proper handwashing
• Taking care of your teeth and gums
• Avoiding crowds and people who are sick
• Asking a healthcare provider about what vaccines are safe

If you're immunocompromised and have a serious illness, consult a healthcare provider immediately. Also, get immediate medical attention if you have difficulty breathing, shortness of breath, or persistent pain or pressure in your chest.

Otherwise, follow a healthcare provider's guidance to care for yourself at home. Those steps will help prevent yourself and others from exposure and infection.

A Quick Review

Talk to a healthcare provider if you're always sick or get sick easily and don't recover as expected. You may be immunocompromised, which means you have a weaker immune system than normal. A rare hereditary disorder, certain medications and treatments, or chronic diseases may cause an immune deficiency.

Take extra precautions to prevent infections, such as proper handwashing, following a healthy diet, staying active, and getting enough sleep. If you have a serious illness or severe symptoms, like difficulty breathing, seek immediate medical attention.