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Patch test in Brazilian children with a clinical diagnosis of atopic dermatitis: a cross-sectional study using an
Janete Raad Rigolon1, Simone Saintive Barbosa2, Ekaterini Simões Goudouris2
1Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; janeteraad@yahoo.com.br.
Insights
Patch testing is crucial for diagnosing allergic contact dermatitis (ACD) in children with atopic dermatitis (AD). Many children with AD react to allergens in skincare products, necessitating a review of treatments.
Area of Science:
- Dermatology
- Pediatrics
- Allergology
Background:
- Atopic dermatitis (AD) is a chronic inflammatory skin condition common in children.
- Allergic contact dermatitis (ACD) is an inflammatory skin disease caused by external agents.
- Impaired skin barrier in AD may increase susceptibility to allergens, risking associated ACD.
Purpose of the Study:
- To evaluate the utility of patch testing (PT) in diagnosing ACD in children with AD.
- To identify common allergens and their sources, particularly in therapeutic skincare products.
Main Methods:
- A cross-sectional study involving 26 children with AD and suspected ACD.
- Patch testing was performed using 30 sensitizers.
- Clinical presentation, patient profile, and sensitizer frequency were analyzed.
Main Results:
- 88.5% of patients reacted to at least one allergen; 80.7% had relevant positive tests.
- Nickel, blue disperse, fragrance mix, and neomycin were the most common sensitizers.
- 73% of patients reacted to allergens found in therapeutic or skincare products.
Conclusions:
- Patch testing is essential for diagnosing ACD in AD children with atypical eczema.
- High prevalence of positive tests, especially to skincare allergens, highlights treatment review needs.
- Recommend expanded PT batteries for pediatric AD to improve ACD diagnosis sensitivity.
Introduction:
Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease mainly affecting children. Similarly, Allergic contact dermatitis (ACD) is an inflammatory skin disease, but unlike AD it results from direct exposure to an external agent. Theoretically, the impaired skin barrier facilitates the penetration of potential allergens. Therefore, AD patients are at risk for an associated ACD, exacerbating their skin condition. Because eczema is similar, performing a patch test (PT) for the differential diagnosis is essential.
Methods:
In this cross-sectional transversal study, we performed a PT with 30 sensitizers in 26 children with AD, selected according to established criteria for suspected ACD, and treated at an AD center of a pediatric university hospital in Rio de Janeiro. Clinical presentation, patient profile, main sensitizers, and frequency of ACD caused by therapeutic skincare products were evaluated.
Results:
In all, 23 (88.5%) patients reacted to at least one allergen, 21 (80.7%) had a relevant positive patch test, and 15 (57.7%) were polysensitized. The main positive sensitizers were nickel (38.5%), blue disperse (30.8%), fragrance mix (30.8%), and neomycin (23.1%). Nineteen (73%) patients reacted to substances present in therapeutic or skincare products.
Conclusion:
Our data underscore the importance of performing a PT in AD children whose eczema has atypical distribution. The expressive percentage of positive tests, especially of allergens in skincare products, indicates the constant need to review the proposed treatments. Therefore, we recommend a specific and expanded PT battery for pediatric AD patients, including a negative control, to increase sensitivity for diagnosing ACD.
