Background: Allergen sensitization differs according to countries and regions. Understanding the characteristics of allergen sensitization in one's own country is useful for the treatment of patients with allergic diseases. Recently, Japanese cedar pollen (JCP) sensitization is increasing in young Japanese children. Therefore, we evaluated allergen sensitization patterns in under 60-month-old Japanese recurrent wheezers using multiple allergen tests.
Methods: Allergen tests for 204 Japanese recurrent wheezers between April 2010 and April 2016 were reviewed. Children were divided into 10 groups by age, in 6-month intervals, from 0 months and analyzed by age group.
Results: Seventy five percent of children were diagnosed as bronchial asthma. Children under 12-months showed sensitization to food allergens, such as egg white (13.3%) and cow's milk (3.3%), and no sensitization to inhaled allergens. However, house dust mite (HDM) and JCP sensitization increased significantly in children 1 to 2 year of age (HDM; 7.7-32.1%, JCP; 3.9-17.9%) and both sensitization increased to most frequent in children over 36 months of age. JCP sensitization was also frequently detected in children with HDM sensitization (47.1%).
Conclusion: Sensitization to inhaled allergens was significantly increased in Japanese recurrent wheezers over 12 months of age and sensitization to HDM and JCP increased to most frequent over 36 months of age. JCP sensitization was established from early childhood and detected frequently in Japanese recurrent wheezers under 60 months of age. These characteristics are the same with HDM sensitization.
Keywords: Japanese cedar pollen multiple allergen test; allergen sensitization; house dust mite; infant.