What Causes Eczema?
Great question! I often get asked about the causes of eczema, or atopic dermatitis (AD), in children. The exact cause isn’t fully understood, but we do know that it’s due to a combination of genetic, environmental, and immune system factors. Let’s break it down.
Genetic Factors Can Cause Eczema
Eczema tends to run in families. If you or your partner have a history of atopic conditions like eczema, asthma, or hay fever, your child is at a higher risk. Studies into the causes of eczema have shown that more than two-thirds of children with eczema have an immediate family member with an atopic condition. If one parent has an atopic condition, the child’s risk of developing eczema is two to three times higher. If both parents are affected, the risk increases to three to five times.
One of the key genetic cause of eczema involves the filaggrin (FLG) gene. This gene is crucial for maintaining the skin barrier. Variations or mutations in the FLG gene can lead to a weaker skin barrier, making the skin more susceptible to water loss and allowing irritants, allergens, and microbes to enter more easily. Children with FLG gene mutations are significantly more likely to develop eczema. About 60% of individuals with FLG mutations develop eczema, three times higher than in the general population.
Immune System and Skin Barrier Dysfunction as a Cause of Eczema
Eczema is often described as a condition driven by both immune system abnormalities and skin barrier dysfunction. The skin’s barrier is like a shield that protects against external irritants and prevents water loss. When this barrier is compromised, it can lead to dry, cracked skin that is more prone to inflammation and infection.
In children with eczema, the immune system tends to overreact to environmental triggers. This overreaction leads to increased inflammation, characterized by elevated levels of certain proteins and cytokines like interleukin (IL)-4, IL-5, and IL-13. These immune responses further weaken the skin barrier and contribute to the itching and redness associated with eczema.
Environmental Triggers for Eczema
Environmental factors also play a significant role in triggering or exacerbating eczema. These can include:
- Allergens: Pollen, dust mites, and pet dander can trigger eczema flare-ups.
- Irritants: Soaps, detergents, and certain fabrics like wool can irritate the skin.
- Climate: Extreme temperatures and low humidity can dry out the skin and worsen eczema symptoms.
- Microbes: Bacterial, viral, and fungal infections can aggravate eczema.
Interestingly, studies suggest that early exposure to certain environmental factors might actually be protective. This is known as the hygiene hypothesis. The idea is that early exposure to a variety of microbes (such as those found in farm environments or through unpasteurized milk) can help the immune system develop in a way that reduces the risk of allergic diseases, including eczema.
How Calgary Weather Affects Children with Eczema
The cold and dry weather in Calgary can significantly exacerbate eczema in children. As winter approaches, the days become shorter, and the combination of dry winds and constant indoor heating creates a challenging environment for those with sensitive skin. The use of furnaces to combat the cold leads to dry indoor air, which strips moisture from the skin, causing it to become dry, itchy, and inflamed. This often results in restless nights for families as children struggle with the discomfort of eczema. November, known as eczema awareness month, underscores the impact of these environmental changes on children with this skin condition, highlighting the need for extra care and attention during this season.
Conclusion
In summary, the cause of your child’s eczema is likely due to a combination of genetic predisposition, immune system responses, and environmental triggers. Understanding these factors can help us manage and treat the condition more effectively.