Immunotherapy with a standardized Dermatophagoides pteronyssinus extract. VI. Specific immunotherapy prevents the onset of new sensitizations in children.

Abstract

The natural history of allergic sensitization is complex and poorly understood. A prospective nonrandomized study was carried out in a population of asthmatic children younger than 6 years of age whose only allergic sensitivity was to house dust mites (HDMs). The study was designed to determine whether specific immunotherapy (SIT) with standardized allergen extracts could prevent the development of new sensitizations over a 3-year follow-up survey. We studied 22 children monosensitized to HDM who were receiving SIT with standardized allergen extracts and 22 other age-matched control subjects who were monosensitized to HDM. The initial investigation included a full clinical history, skin tests with a panel of standardized allergens, and the measurement of allergen-specific IgE, depending on the results of skin tests. Children were followed up on an annual basis for 3 years, and the development of new sensitizations in each group was recorded. Ten of 22 children monosensitized to HDM who were receiving SIT did not have new sensitivities compared with zero of 22 children in the control group (p = 0.001, chi square test). This study suggests that SIT in children monosensitized to HDM alters the natural course of allergy in preventing the development of new sensitizations.