Allergic contact dermatitis in children: the Ottawa hospital patch-testing clinic experience, 1996 to 2006.

BACKGROUND

Allergic contact dermatitis in children is a significant clinical problem. Patch testing is a diagnostic tool for the evaluation of patients with suspected allergic contact dermatitis.

OBJECTIVES

To determine the frequency and relevance of positive patch-test results in children and to identify the most common allergens in children at our clinic.

METHODS

Retrospective chart review of 100 children and adolescents, aged 4 to 18 years, who were patch-tested at the Ottawa Hospital patch-testing clinic between 1996 and 2006. The children were patch-tested with the North American Contact Dermatitis Group (NACDG) standard series, supplementary series if indicated, and their own products if available.

RESULTS

Seventy percent of children had at least one positive patch-test reaction; 55.8% of positive patch-test reactions were relevant. The ratio of females to males was 62:38. The most common allergens were nickel sulfate (26%), cobalt (14%), fragrance mix (7%), neomycin (7%), colophony (6%), formaldehyde (4%), lanolin (4%), quaternium-15 (4%), and para-phenylenediamine (4%). Nickel co-reacted with cobalt (68%) and palladium (100%). Of children tested, 41% had a history of atopic dermatitis.

CONCLUSIONS

The frequency of positive and relevant allergens in children is similar to that in adults as compared with data from the NACDG 2001-2002 study period. Differences between the top 10 allergens in children and adults were seen. Nickel and cobalt were more common allergens in children, and colophony, lanolin, and para-phenylenediamine ranked in the top 10 allergens among children.