Contact dermatitis in children

Frequency of contact allergy in German children and adolescents patch tested between 1995 and 2002: results from the Information Network of Departments of Dermatology and the German Contact Dermatitis Research Group

Allergic contact dermatitis (ACD) affects approximately 7% of the general population. To evaluate the frequency of ACD in children, we analysed patch test results collected by the Information Network of Departments of Dermatology between 1995 and 2002. Data of 285 children (6-12 year) and 2175 adolescent patients (13-18 year) were analysed to determine the frequency of sensitization to the 30 most common contact allergens, adjusting for age and sex. As control group, we defined adult patients (60-66 year, n = 7904). The top allergens in children were thimerosal, gentamicin sulphate, nickel-II-sulphate, ammoniated mercury, cobalt-II-chloride, fragrance mix, bufexamac, Compositae mix, propylene glycol and turpentine. The overall proportion of sensitized patients according to the patch test results was 52.6% in the children group compared to 49.7% in the adolescent group. These findings were similar in the adult group at 52.2%. The detailed analysis regarding sex, occupation, atopy, site of eczema and age showed distinct patterns in each group indicating age-specific exposures. Atopy-related diseases were more common in children compared to adults. On the basis of the data of this study, the relationship between atopy and the risk of development of ACD, at least in children, needs further investigation.

Allergic contact dermatitis

Allergic contact dermatitis (ACD) in children is underrecognized. It is often confused with antibody-mediated allergies such as urticaria or allergic rhinitis, but the mechanism in ACD involves T lymphocytes and not antibody. Surprisingly, sensitization to common allergens is likely to occur in infancy. All contact allergens are weak allergens requiring repeated exposure over long periods of time. Detection of specific allergens is by epicutaneous (patch) testing and will provide the basis for allergen avoidance therapeutic strategies.

Does sensitization to contact allergens begin in infancy?

OBJECTIVE

Because previous studies have found allergic contact sensitization common in children by 5 years of age, our aim was to determine the prevalence of positive epicutaneous test results in children <5 years of age and to determine whether sensitization to contact allergens was as common in infancy.

METHODS

We recruited 95 asymptomatic children 6 months to 5 years of age from well-child visits at Denver area pediatric practices for epicutaneous patch testing using the T.R.U.E. Test system. Allergens were placed on the skin for 48 hours, and at a later follow-up visit, positive reactions were evaluated.

RESULTS

A total of 85 patients completed the study. Of these, 20 (24.5%) had 1 or more positive reactions to the tested allergens. Positive reactors ranged from 6 to 65.5 months of age, with an average of 30.4 months of age. Of the children, 16 reacted to 1 allergen, and 4 reacted to 2. Eleven positive reactions were observed to nickel, followed by 8 to thimerosal. Other positive reactions were to neomycin, cobalt, and kathon CG.

CONCLUSIONS

Children as young as 6 months of age may be sensitized to contact allergens. Within this pediatric population, the prevalence of sensitization is 24.5%. Sensitization to contact allergens may occur in infants.