Eczema (Atopic Dermatitis)
I’m sure most of us have heard about atopic dermatitis (commonly known as eczema) by now as it’s a very common condition in our society today. Atopic dermatitis is a complex chronic inflammatory disorder involving the immune system, epidermal barrier dysfunction and several possible environmental factors. It most often begins in childhood, but can begin later in life. Up to 20% of children and 1-3% of adults are diagnosed with eczema. There seems to be a strong genetic link as well.
What does it look like?
Patients with eczema commonly have very dry, itchy, red patches on their skin. This can be anywhere but tends to show up on the face, neck, arms & legs (especially flexural surfaces) and even the butt! It can range from mild to debilitating for individuals.
Food allergies, sensitivities and intestinal permeability
Now, what should be considered if someone has eczema, you ask? As with almost anything I write about… it depends on the individual person. Looking at potential allergic triggers is very important, this can include true IgE allergies or IgG food sensitivities. IgE allergies are “true” allergies that cause an immediate reaction (ie anaphylaxis to peanuts), whereas an IgG sensitivity is a delayed hypersensitivity reaction (ie experiencing diarrhea hours after eating yogurt). Common offending foods are dairy, eggs, peanut or other nuts, wheat and fish, although there are many more. These food sensitivities can damage the intestinal lining causing increased intestinal permeability, potentially allowing undigested food particles into the bloodstream. These particles act as an antigen (foreign substance to the body) and the immune system reacts by creating an antibody to that antigen. This immune complex causes an immune & inflammatory cascade which can show up in the skin (and many other areas of the body). It’s also common to see concomitant asthma and/or allergic rhinitis in those with eczema, highlighting the importance of investigating allergies/sensitivities and also the state of that individual's immune system in general. Often the immune system becomes hyperactive, leading to an inflammatory response and exhibiting as these symptoms.
Imbalance of bacteria
Another potential cause that may be useful to investigate is dysbiosis, an imbalance of different types of bacteria in the gut. If your gut bacteria isn’t getting the proper food/nutrition, you’ve had a lot of the “good bacteria” killed off by substances like antibiotics or antibacterials, or you’ve experienced bouts of food poisoning, this can lead to dysbiosis. Any presentation in the skin is usually the external presentation of things going on in the gut. If your gut isn’t happy, your skin might not be very happy either because they are really good buds.
The negative effects of stress
Stress is another potential contributor of atopic dermatitis, and can worsen the severity of the condition. When an individual is chronically stressed, glucocorticoid (cortisol) production is increased which alters cell-mediated immunity and modulates inflammation. T helper cell 2 (Th2) becomes dominant, increasing production of IgE and therefore increasing the probability of allergies. Stress in the short term can actually help symptoms of atopic dermatitis, but will ultimately make it worse.
The skin barrier & genetics
Dermal barrier function is also implicated in patients with atopic dermatitis. Researchers have identified the filaggrin gene as a contributor. It influences production of structural epidermal proteins that are involved in the complex differentiation of keratinocytes (primary cell type in the epidermis - the outermost layer of the skin). A loss-of-function of the filaggrin gene has been repeatedly found in individuals with atopic dermatitis.
What about contact dermatitis?
Contact dermatitis is an irritation of the skin due to direct skin contact with a substance or material that an individual is allergic or sensitive to or a toxin. Sometimes contact dermatitis can be misdiagnosed as eczema, as the presentation can be similar. This is why it’s important to be conscious about what products you use on your skin or your clothes and which materials your clothes or jewellery are made of. Once the offending substance or material is taken out, the irritation and rash should resolve shortly.
The bottom line:
Eczema is a multi-factorial, complex condition with many potential causes including food sensitivities, allergies, genetics, bacterial imbalances, intestinal permeability, immune system dysregulation, inflammation and enzyme deficiencies. Individuals should not be given only corticosteroids to band-aid their symptoms, but the root cause should be addressed and treated.
Naturopathic therapies typically aim, depending on the individual, to reduce inflammation, remove offending foods, correct dysbiosis, heal the gut lining, manage stress, modulate the immune system and strengthen & soothe the skin barrier.
***This is not medical advice. Please see a licensed naturopathic doctor or other healthcare practitioner for evaluation and treatment if you are experiencing these symptoms.
References:
Gonzalez, Mercedes. “Atopic Dermatitis (Eczema).” Merck Manual, Merck Sharp & Dohme Corp., 08/19, https://www.merckmanuals.com/professional/dermatologic-disorders/dermatitis/atopic-dermatitis-eczema?query=atopic%20dermatitis
Stemmler, Susanne, and Sabine Hoffjan. "Trying to understand the genetics of atopic dermatitis." Molecular and cellular probes 30.6 (2016): 374-385.
Lin, Tzu-Kai, Lily Zhong, and Juan Luis Santiago. "Association between Stress and the HPA Axis in the Atopic Dermatitis." International journal of molecular sciences 18.10 (2017): 2131.
Høst, Arne, and Susanne Halken. "Practical aspects of allergy-testing." Paediatric respiratory reviews 4.4 (2003): 312-318.