Eczema is an umbrella term that describes various inflammatory skin conditions, or dermatitis. Several types of dermatitis involve an overreaction from the immune system, and some research suggests autoimmunity may play a role.
An autoimmune disease is the result of the immune system mistakenly attacking the body’s healthy tissues. Typically, this is different from other types of immune response, such as an allergic reaction, which happens when the body perceives exposure to a specific substance as a threat.
However, a study in the Journal of Autoimmunity notes that one type of eczema, atopic dermatitis (AD), may start as an allergic reaction and progress to an autoimmune response.
Eczema refers to a group of conditions that cause itchy, inflamed rashes on the skin. If an individual has a light skin tone, eczema may appear in red patches. The patches may appear brown, purple, or gray on darker skin tones.
Doctors currently recognize seven types of eczema, which are:
- contact dermatitis
- atopic dermatitis
- stasis dermatitis
- dyshidrotic eczema
- seborrheic dermatitis
- nummular eczema
Most types of eczema appear to have some links to the immune system, but the evidence is limited.
This article looks at three types of eczema: atopic, dyshidrotic, and nummular eczema and explores their possible links to autoimmunity.
The American Academy of Dermatology Association states that (AD) is a common form of eczema that does not have a single cause. Researchers think AD develops due to a combination of genetics, a sensitive immune system, and environmental factors that trigger the symptoms. Some evidence suggests that autoimmunity may also drive it.
Dermatologists believe that people with AD have a genetic trait that means their skin loses moisture too quickly, causing gaps in the skin barrier. This can lead to dry, less well-protected skin.
This alone is not always enough to cause AD. Other factors that may put people predisposed to the condition at risk of developing it include:
- living somewhere that is cold and damp for at least some of the year
- exposure to pollution and tobacco smoke
Autoimmunity may also contribute to AD. The authors of a 2021 study suggest that AD may start as an allergic response before progressing to an autoimmune response. They argue that this may be what causes chronic inflammation and relapses.
However, more research on how AD develops is necessary to confirm that it is an autoimmune disease, and if so, what treatments might help.
Learn about some treatments for atopic dermatitis here.
Dyshidrotic eczema, or pompholyx, causes small, itchy blisters on the soles, palms, and edges of the fingers and toes. The cause is unknown, but many people living with the condition also have another form of eczema. In addition, doctors have noted that dyshidrotic eczema can run in families.
Some common triggers for flare-ups include:
- metal allergies, especially nickel allergy
- seasonal allergies, such as hay fever
- heat and humidity
Few studies have looked at the immune response in people with dyshidrotic eczema, so it is unclear if it has an autoimmune component.
Nummular eczema causes coin-shaped patches that are often itchy and sometimes oozing. The patches can appear anywhere on the skin. Experts do not know what causes nummular eczema, but they think it has links with:
- having dry or sensitive skin
- having other types of eczema
- metal allergies
- cuts, insect bites, or chemical burns
- low blood flow in the legs, if the patches appear there
No research has looked at whether nummular eczema could be an autoimmune disease.
Learn more about the different types of eczema here.
Autoimmune conditions can cause eczema and skin rashes, but presenting with either of these conditions would not necessarily lead a doctor to diagnose an autoimmune disease. Eczema is widespread and can occur on its own.
People can also have eczema and autoimmune conditions together, and one may worsen the other. Conditions that increase the sensitivity of the immune system or cause inflammation may exacerbate eczema.
Additionally, eczema can occur as a secondary complication of an autoimmune disease. For example, inflammatory bowel disease (IBD) can lead to difficulty absorbing nutrients.
Skin conditions can also be a side effect of treatments for autoimmune diseases. For example, infliximab (Remicade), one of the medications doctors prescribe to treat Crohn’s disease, may cause eczema.
A 2015 study found that 29.6% of people experienced scaling eczema and 18.5% developed exacerbated atopic eczema after taking this medication.
In addition to autoimmunity, other factors can activate the immune system, including:
- irritants, such as artificial fragrance, harsh cleaning products, or smoke
- friction on the skin from itchy fabrics
- certain bacteria, viruses, and yeast
- dysbiosis, which is when the microbiome in the gut or on the skin is imbalanced
Things that reduce the skin’s ability to hydrate and protect itself can also cause symptoms. For example, frequent hand washing, use of alcohol hand sanitizer, and hot baths can cause skin dryness. Moisturizing after getting the skin wet or using sanitizers that contain moisturizers can help.
Some of these factors have a more significant influence on certain types of eczema than others. For example, experts think that a specific kind of yeast, known as Malassezia, causes seborrheic dermatitis.
This yeast usually lives on the skin, but it can trigger an immune response if it overgrows. Antifungal creams and shampoos help control it.
It is crucial that doctors identify the specific type of eczema to understand its causes and prescribe the best treatments. People can have more than one type of eczema in different places on their bodies, which may need different approaches.
Eczema can also look very similar to other conditions, such as skin infections, psoriasis, and actinic keratosis, a precancerous skin rash.
Speak with a dermatologist if they have not yet made an official diagnosis or if conventional eczema treatments are not working.
Learn more about when skin rashes can signify cancer.
Eczema is an umbrella term for seven conditions that cause inflammation and itching. Each is slightly different and can have various triggers.
More research into AD may lead to new treatments that target the mechanism that causes it.
Speak with a doctor who understands eczema to get a diagnosis and treatments that control the symptoms.