To get us started, what are the common symptoms of eczema?
The answer is E ─ all of the above! Eczema is an inflammatory skin condition associated with skin sensitivity and a dry, itchy rash. It is generally a chronic condition, although it can improve significantly, or even clear completely, in some individuals depending on type and severity.
What is the global prevalence rate of eczema?
An average of 10% of individuals will develop eczema during their lifetime (although estimates range from 3–10%). Prevalence has also been shown to peak in early childhood, with up to 20% of infants affected [1,2].
Which is the most common form of eczema?
There are seven forms of eczema: atopic dermatitis, contact dermatitis, neurodermatitis, dyshidrotic eczema, nummular eczema, seborrheic dermatitis and stasis dermatitis. However, atopic dermatitis is the most common.
On what parts of the body are eczema break outs most likely?
Eczema break outs are most commonly found on the hands, elbows and face.
On darker skin, what colour might eczema rashes look like?
Eczema rashes on darker skin will appear more purple, brown or grey compared to the reddish colour seen on lighter skin tones.
Eczema has been linked to damage of which skin structure?
Eczema has primarily been linked to impairment of your skin barrier, which plays a crucial role in human health. The skin barrier plays a key role in our immune system, protecting the body against pathogens (harmful microbes) and disease. It is also critical for maintaining healthy skin as it helps to lock in moisture and additionally protects us from UV and mechanical damage. Again, the initiation and progression of eczema is not yet fully understood, but during eczema development an impaired skin barrier is thought to result in water loss and exposure to irritants, which can cause or contribute to the dry, itchy skin experienced by sufferers [3].
For any science buffs – mutations in which key skin protein have been found to be a major predisposing factor for atopic dermatitis?
Filaggrin is a key protein required for the formation of our outer skin barrier, and it is essential for hydration. Mutations in filaggrin have been shown to be a major genetic predisposing factor for atopic dermatitis – mutations that are carried in up to 10% of people [4,5].Loss of filaggrin leads to a poorly formed outer skin barrier that is also prone to water loss and infiltration of allergens and irritants [5]. One reason for this link is that filaggrin is responsible for producing key amino acids and structural and hydrating derivatives such as ‘natural moisturizing factors’ – decreased levels of which have also been linked to atopic dermatitis [4].
True or false, flare-ups of eczema have been associated with increased microbial diversity on the skin and in the gut?
False! On the skin, eczema flares are actually associated with a loss in microbial diversity, which might allow certain pathogenic bacteria populations to grow [6,7].
The increased presence of which bacteria has been associated with eczema development?
Staphylococcus aureus populations have been found to increase on the skin of eczema suffers. In fact, 7/10 of those affected by atopic dermatitis carry S. aureus on the skin, compared to 1/5 of healthy individuals [8].It’s not just in eczema that we see links between the skin disorder and certain bacterial species. For example, the bacteria Cutibacterium acnes has been linked with acne, while Streptococcus pyogenes has been linked with psoriasis [9,10].
Which of the following are eczema management options?
The answer is all of the above. For those suffering from eczema, daily use of moisturizers can help stop the skin becoming too dry, and use of topical corticosteroid creams and ointments can reduce swelling and flare-ups. Antibiotics and antiseptic products may also be approaches for management, but for all cases a GP or skin specialist should be consulted to identify best path forward. It’s also important to avoid products that may trigger eczema flare-ups, such as harsh and irritating fragrances that could result in allergic reactions [11].
A link has also been found between eczema and food allergies, but what is the strongest risk factor for food allergies?
While there is a hereditary component for the development of food allergies, eczema (or atopic dermatitis) is actually the strongest risk factor! Generally considered chronic and multifactorial, atopic dermatitis can also be part of the so-called ‘atopic march’. This means that starting with symptoms such as dryness and itchiness of the skin, atopic dermatitis may also later lead to a series of other allergic disorders if not managed, including food allergies.Mechanistically, this may be a knock-on effect from an impaired skin barrier and immune system, and it has been shown that the reduced bacterial diversity in children with atopic dermatitis can determine the course of food allergies [12].
What’s the running theory for the link between eczema and the development of food allergies during infancy?
We don’t know the exact cause, but researchers suspect that the skin plays a key role in shielding us from allergens in the environment. When the skin is compromised due to eczema, the skin’s immune cells become more exposed to food proteins in the environment, increasing the likelihood of an immune response through exposure to environmental food allergens than if those same allergens were to enter through the digestive tract [11].
