What is triggering the eczema flare?

Identifying Triggers of Eczema Flares

To identify what is triggering an eczema flare, a comprehensive evaluation of potential environmental factors, allergens, and irritants is necessary, with special attention to the patient's exposure history and pattern of symptoms.

Common Triggers of Eczema Flares

Environmental Factors

• Hot weather can lead to increased scratching on the same day of exposure, while damp weather may trigger flares 2-4 days after exposure 1, 2
• Sweating is associated with elevated scratch scores approximately 3 days after exposure 1, 2
• Stress has been shown to exacerbate eczema symptoms with a lag of about 3 days 1
• Combinations of environmental triggers acting together may have stronger effects than individual exposures 2

Clothing and Direct Contact Irritants

• Nylon clothing is significantly associated with eczema worsening, particularly affecting the trunk and limbs 2
• Wool clothing can exacerbate symptoms, especially on the trunk 2
• Soaps and detergents remove natural lipids from the skin surface, worsening already dry skin in patients with atopic eczema 3
• Shampoos may trigger flares, with effects enhanced in cold weather 2

Allergens

• Food allergies may trigger eczema, particularly in children under 5 years with moderate to severe disease 3
• Common food allergens include cow's milk, eggs, wheat, soy, and peanut in young children; tree nuts, shellfish, and fish in older children 3
• Aeroallergens such as house dust mites, pollens, animal dander, and fungi can trigger flares, especially in those with moderate to severe atopic dermatitis 3
• Contact with unfamiliar pets has been associated with disease worsening 2
• Exposure to dust has been linked to increased eczema severity 2

How to Identify Triggers

Clinical History and Pattern Recognition

• Ask about temporal relationship between exposures and symptom flares 3
• Look for pattern of distribution: aeroallergen-triggered eczema may be more severe on exposed surfaces of face, neck, arms, legs, and "V" area of chest 3
• Bacterial infection is suggested by crusting or weeping, while grouped, punched-out erosions indicate herpes simplex infection 3

Allergy Testing

• Consider limited food allergy testing in children under 5 with moderate to severe atopic dermatitis who have: 1) persistent disease despite optimal management, 2) reliable history of immediate allergic reaction after food ingestion, or 3) both 3
• Skin prick testing (SPT) and serum-specific IgE level determination can assess for immediate/type I hypersensitivity reactions 3
• Patch testing should be considered for suspected allergic contact dermatitis, particularly in patients with hand and eyelid eczema 3

Monitoring and Documentation

• Patient diaries recording daily severity and exposure to potential triggers can help identify patterns 1, 2
• Note that some triggers may have delayed effects (2-4 days after exposure) 1

Practical Approach to Trigger Identification

1. Document flare patterns: Record when flares occur and their severity
2. Track exposures: Note potential triggers including clothing, foods, environmental conditions, and stress
3. Look for time patterns: Some triggers cause immediate reactions while others have delayed effects of 2-4 days
4. Consider combination effects: Multiple triggers acting together often worsen symptoms 2
5. Targeted testing: Perform appropriate allergy testing based on history and suspected triggers 3

Common Pitfalls to Avoid

• Assuming all reactions are immediate - many triggers have delayed effects of several days 1
• Focusing on a single trigger when combinations of factors may be responsible 2
• Performing broad panel allergy testing without a history of reaction, as positive tests may reflect sensitization without clinical relevance 3
• Overlooking non-allergic triggers such as stress, temperature, and humidity 1
• Neglecting to consider secondary bacterial or viral infections as causes of sudden deterioration in previously stable eczema 3

By systematically evaluating potential triggers through careful history, appropriate testing, and monitoring of symptom patterns, clinicians can help patients identify and avoid specific factors that exacerbate their eczema.