Allergic contact dermatitis in children: trends in allergens, 10 years on. A retrospective study of 500 children tested between 2005 and 2014 in one UK centre.

SummaryBackground Contact allergy in children is becoming increasingly recognized as a cause of eczema. The causal agents may change with time, but there are few comparative data for this age group. Objectives To compare data from the past 10 years with a similar study from the previous decade. Methods Between 2005 and 2014, 500 consecutive children who had been patch tested at Leeds Teaching Hospitals were identified, and the results were reviewed. Results Twenty-seven per cent (134 cases) of children had one or more positive patch test findings. The mean ± standard deviation age of patients with a positive test reaction was 11.9 ± 4.1 years, which was significantly higher than that of patients with a negative result (10.9 ± 4.0 years) (p = 0.01; Mann–Whitney U-test). No significant relationship between sex and a positive patch test result was found (p = 0.48, chi-squared). Allergy to nickel was the most frequent finding, although this accounted for 18%, rather than 33% (1995–2004), of all positive reactions. The next most common allergens included fragrance mix 1 (17%), p-phenylenediamine (16%), and methylchloroisothiazolinone/methylisothiazolinone (6%). Conclusions Although the overall incidence of contact allergy in our paediatric population is static, there has been a significant change in the allergens detected, probably as a result of changes in European legislation and cosmetic product use in children.