It is "common" for a reason: most of us get a cold about once a year. More than 200 viruses can cause the well-known symptoms, so it is not surprising they affect so many people. A person who catches colds more often than their peers might have a weak immune system. In addition to being more susceptible to viruses, a number of signs and symptoms point to immunodeficiencies.
People with weak immune systems often contract multiple infections every year. In fact, more, longer-lasting infections is the main symptom of primary immunodeficiency disorders, of which there are more than 200, affecting about half a million people in the U.S.. As well as a cough and runny nose, people with immune deficiency conditions develop sinus, fungal, and ear infections more regularly.
Conditions like common variable immune deficiency (CVID) cause an excess of immune cells to accumulate. The lymph nodes — small, essential organs that are part of the lymphatic system — swell up when they are working to fight off an infection, becoming larger and tender. Most people think of the nodes on either side of their neck because they're most noticeably affected by a head cold or sinus infection. However, there are also lymph nodes in the armpits and groin.
On top of getting more infections, people with weak immune systems tend to take longer to feel better. Immunodeficiency disorders slow the immune system's response, and, as a result, it takes these systems longer to evict infections. This does not just apply to sinus infections or colds, either. Often, people with weakened immune systems notice even small cuts take longer to heal. Their bodies are slower to send nutrient-rich blood to the injured site to regenerate lost skin cells. Unfortunately, a cut that does not heal quickly is also more prone to becoming infected, so it is especially important that immunocompromised people keep injured areas clean.
Anemia develops when a person has insufficient red blood cells. Some people with weakened immune systems develop autoimmune hemolytic anemia: their bodies produce autoantibodies that attack red blood cells in the same way they're supposed to attack viruses and other invaders. The opposite is also true: too few red blood cells impacts immunity. Anemia and other effects of weakened immunity — predominantly a need for the body to be constantly fighting off illness — can also lead to persistent tiredness and fatigue.
Conditions like inflammatory bowel disease and symptoms such as recurring diarrhea can indicate a weak immune system; research shows most people with CVID develop gastrointestinal (GI) issues that can significantly impact their health. Experts theorize that these digestive problems are related to T cells, which are components of the lymphatic system that play a major role in immune function. Children with CVID can experience growth and developmental delays due to these GI issues. A lack of T cells is also linked to severe viral infections.
Most people have heard or personally discovered that stress makes them more susceptible to illness, and that is not all in our heads. There is plenty of research to support the connection between high stress and low immunity. Like many indicators of a weak immune system, there is a circular nature to this issue: stress can cause low immunity, and low immunity can increase stress. When the brain and body experience heightened stress levels, they drastically reduce or completely cease the production of T cells and other essential natural tools against infection.
Some people with primary immunodeficiency disorders develop buildups of inflammatory cells in areas other than the lymph nodes. These cells, called granulomas, can congregate in the lungs, liver, and even the skin. If the body is also underproducing protective white blood cells or attacking its own red blood cells, the inflammatory bodies can increase largely unchecked, causing significant and potentially dangerous inflammation or infection in vital organs.
Allergies often result from an overeager immune system that jumps to the body's defense against mostly harmless substances like dust and pet hair. Given that, it might be surprising to learn that allergies can also point to immunodeficiency. In people with weak immune systems, it can be difficult to determine whether the repercussions — such as rhinosinusitis or fluid and pressure buildup in the nasal passageways — stems from allergies or an infection that requires medication. Likewise, doctors can confuse asthma and pneumonia in people with immunodeficiencies.
The lymph nodes, organs, and sinuses are not the only areas that can become inflamed in a person with an immunodeficiency. Joint pain and arthritis are common signs of these conditions. Some individuals develop polyarthritis, which affects a variety of larger joints, including the wrist, ankle, elbow, and knee. As with allergies, the pain may be due to inflammation or a more serious infection, and doctors often have to withdraw joint fluid samples for testing. Luckily, there are successful treatments for general joint inflammation.
Many conditions affect immunity and can leave a person with an immunodeficiency that their doctor may or may not link to a larger issue. Disorders that primarily affect the immune system, such as lupus and HIV/AIDS, quickly come to mind, but type 1 diabetes, rheumatoid arthritis, and cancer can also lead to or indicate a weak immune system. Disease treatments like chemotherapy can also compromise the immune system, causing many signs and symptoms.
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This site offers information designed for educational purposes only. You should not rely on any information on this site as a substitute for professional medical advice, diagnosis, treatment, or as a substitute for, professional counseling care, advice, diagnosis, or treatment. If you have any concerns or questions about your health, you should always consult with a physician or other healthcare professional.