Skin sensitization in asthmatic children less than 36 months of age

Atopy is reported to play an insignificant role in wheezing during infancy in contrast to later childhood. For this reason skin testing may not be included in a workup of wheezing infants.

In order to evaluate the degree and evolution of skin sensitization to allergens in infants with asthma, we have retrospectively analyzed the skin test results from 40 referred asthmatic children less than 36 months of age, who had had more than three wheezing episodes and whose symptoms improved on treatment with beta-agonist and anti-inflammatory agents.

Skin sensitization (epicutaneous) to common indoor and outdoor aeroallergens and foods were demonstrated in 23 (58%) of these patients. Asthmatic children with the onset before 12 months of age and duration of less than 12 months were sensitive predominantly to foods. Those with later onset asthmas and longer duration developed sensitivity first to indoor and then to outdoor allergens. The most common food, indoor, and outdoor allergens were egg, dust mite, and pollens, respectively. Six of these patients had repeat skin tests later. Two demonstrated a decrease in skin sensitivities to foods, one gained a new sensitivity to grass, while three remained unsensitized.

Skin sensitization to allergens was common in selected asthmatic infants and evolves in the order of exposures: foods, indoor allergens, and outdoor allergens. Repeat skin tests showed changing skin test patterns in some patients.