Changes in skin prick test reactivity over 7-14 years in a population of food allergy children and asthmatic sympoms.

Background: Allergic disorders are an increasing health problem among children.Aim: to describe the prevalence of sensitization to common food and inhalant allergens at different ages and the association with asthmatic symptoms.Methods: 174 children with positive Skin Prick Test (SPT) to at least one food allergen <36 months were called after a follow-up period of 7-14 years to repeat SPT, to complete a questionnaire about asthmatic symptoms, and to perform spirometry.Results: 174 children complete the questionnaire: 25.8% had wheezing, 34.4 % had dry cough and 35.6% reported diagnosis of asthma. At the first observation 65 (37.3%) had positive SPT only to food allergens (F) and 109 (62.6%) had sensitization to food and inhalant allergens (F+I). At the second observation in the group with single sensitization to F 50% lost sensitization, 10% retained sensitization to food and developed sensitization to inhalants (F+I) and 40% showed sensitization only to inhalants. In the group with double sensitization (F+I) at the first observation: 50% remained positive to both allergens (F+I), more than 40% were positive only to inhalants and a small percentage (< 10%) became negative. The sensitization profiles differed significatly between two groups (F and F+I). FEV1 and FEF 25-75 were significantly lower in the group F+I at the first observation than in the group F (< p 0-01).Conclusion: We found an association between changes in SPT positivity and the development of asthmatic symptoms. The double sensitization (F+I) as well as the early sensitization to atlants would seem to correlate with the persistence of the allergy and with the development of respiratory disease.