Patch testing in infants

The aim of this study was to evaluate the frequency of contact sensitization in infancy because very few data on this topic are available in the literature. We patch tested 53 children, ranging in age from 3 months to 2 years, admitted to our allergological outpatient department for eczematous dermatitis with the Italian Research Group on Contact and Environmental Dermatitis standard series. Thirty-nine of the 53 patients were affected by atopic dermatitis. Thirty-two patients (60%) showed positivities to patch tests; 16 of these were polysensitized. Twenty-five of the contact-sensitized children had atopic dermatitis. The haptens responsible for the highest number of positivities were thimerosal and nickel, followed by ammoniated mercury, disperse dyes, fragrances, and preservatives. Our results stress the importance of patch testing patients with atopic dermatitis or suspected contact dermatitis younger than 2 years of age.