What causes atopic dermatitis (eczema) flares?

From the Guidelines

Eczema flares are primarily triggered by a combination of dry skin, excessive sweating, changes in temperature or humidity, irritants, allergens, infections, and stress, as identified in the Taiwan guidelines for the diagnosis and management of pediatric atopic dermatitis 1. These triggers disrupt the skin barrier and activate the immune system, leading to inflammation and the characteristic symptoms of eczema. Key factors that contribute to eczema flare-ups include:

• Dry skin, which compromises the skin barrier
• Excessive sweating, which can irritate the skin
• Changes in temperature or humidity, which can dry out or irritate the skin
• Irritants, such as soaps or detergents, which can damage the skin barrier
• Allergens, which can trigger an immune response
• Infections, which can exacerbate inflammation
• Stress, which can trigger or worsen eczema symptoms According to the Taiwan guidelines, regular use of emollients can help prevent eczema flare-ups by improving skin barrier function and reducing the need for topical corticosteroids 1. Additionally, topical corticosteroids are considered a first-line treatment for eczema flare-ups, but their use should be limited in sensitive skin areas to avoid skin atrophy 1. Overall, managing eczema involves identifying and avoiding personal triggers, maintaining skin hydration, and using prescribed medications as needed to control symptoms and prevent flare-ups.

From the Research

Eczema Flare Causes

• Eczema flare-ups are caused by a complex interaction of immune dysregulation, epidermal gene mutations, and environmental factors that disrupt the epidermis, causing intensely pruritic skin lesions 2
• The attributes of eczema include dry skin, pruritus, lichenification, and frequent eczematous abrasions, which have a strong heritable aspect and typically occur with asthma and allergic rhinitis 3
• The complex pathological mechanism behind eczema etiology is epidermal barrier destruction resulting in the lack of filaggrin protein that can induce inflammation and T-cell infiltration 3
• T-helper 2 cell-mediated pathways also bear the responsibility of damage to the epidermal barrier 3
• Certain causative factors for eczema include microbial imbalance of skin microbiota, immunoglobulin-E-induced sensitization, and neuro-inflammation 3

Triggers of Eczema Flare

• Repeated scratching triggers a self-perpetuating itch-scratch cycle, which can have a significant impact on the patient's quality of life 2
• Environmental factors, such as irritants and potential allergens, can trigger eczema flare-ups 4
• Mutations in filaggrin, a key protein in epidermal differentiation, have also been identified in early-onset and severe atopic dermatitis 4

Treatment and Management

• Maintenance therapy consists of liberal use of emollients and daily bathing with soap-free cleansers 2
• Use of topical corticosteroids is the first-line treatment for eczema flare-ups 2
• Topical calcineurin inhibitors, such as pimecrolimus and tacrolimus, can be used in conjunction with topical corticosteroids as first-line treatment 2
• Ultraviolet phototherapy is a safe and effective treatment for moderate to severe eczema when first-line treatments are not adequate 2