title: Does sensitization to contact allergens begin in infancy?
abstract: 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.
authors.affiliation: Department of Pediatrics, University of Colorado Health Sciences Center, Denver, Colorado, USA.
authors.forename: A L
authors.initials: AL
authors.lastname: Bruckner
authors.forename: W L
authors.initials: WL
authors.lastname: Weston
authors.forename: J G
authors.initials: JG
authors.lastname: Morelli
mesh_terms: D017668:Age of Onset; D002675:Child, Preschool; D017449:Dermatitis, Allergic Contact / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D010328:Patch Tests