Abstracts of the 12th European Society for Pediatric Dermatology (ESPD) Congress, 12-14 June, 2014, Kiel, Germany.

Abstract

Background: Data on contact allergies in children are conflicting. This study aims to identify frequent contact allergens and their relevance in children with and without atopic dermatitis (AD). This will allow better identification of potential sensitizers and improve patients' care in children. Methods: We conducted a retrospective study of 1083 patient records of children aged 0-18 years suspected of having contact dermatitis. Children were patch tested between 1996-2013 in 3 University Hospitals in the Netherlands. Patch testing was performed using the Chamber technique and the TRUE test. Patients were excluded (n = 71) when not tested with at minimum the European Baseline Series. Results of additional patch tested series, tested “on indication” according to the patient history, were also evaluated. The primary analysis was performed on routinely tested allergens, while the secondary analysis was performed on the combined data from routinely tested allergens plus allergens tested “on indication”. Provided relevance scores are the current “certain” and “probable” relevance scores combined. Statistical analysis was performed with Chi-square or Fisher's exact test. Results: 1012 children (female 63%, mean age 13 years) were included, and 469 (46%) of children developed ≥1 positive reaction. The most frequent reactions were to nickel (16,4%: 164/998), cocamidopropyl betaine (CAPB) (15,9%: 54/339), fragrance mix I (9,9%: 100/1008), Amerchol L-101 (8,8%: 30/339) and wool alcohols (6,2%: 63/1009). 52% of children had AD, 39% did not have AD and in 9% had an unknown atopic status. Sensitization rates for children with and without AD were similar (48% vs. 47%). In children with AD, CAPB was the most frequent allergen (19%; 33/174). Compared to children without AD, the primary analysis showed no significant difference. However, when analyzing all reactions to CAPB found in the routinely tested series plus the “on indication” tested series together, a significant difference between children with and without AD was seen for CAPB (17% vs. 9%; p <0.02). Reactions to CAPB were considered relevant in the majority of cases (56%). Reactions to wool alcohols (p <0.04) and fragrances (p <0.05) were found significantly more often in children with AD vs. children without AD, with relevance scores of at least 59% and 63%, respectively. Surprisingly, less positive reactions to wool alcohols and fragrances were found with the TRUE test as compared to the Chamber technique. Conclusion: Sensitisation rates in children with and without AD were similar, but significant differences were found in the reacting allergens between these 2 groups. Reactions to CAPB, fragrances and wool alcohols are more common in children with AD, and these should be tested when a contact dermatitis is suspected in this population. The difference in positive reactions to wool alcohols and fragrances between TRUE test and Chamber technique is striking and needs further investigation.