2010 Volume 24 Issue 5 Pages 659-668
This paper describes the phenotypes of pediatric asthma, particularly virus-induced asthma caused by virus infection. Many cases of asthma in preschool children are induced by virus infection and may develop airway remodeling. Therefore, the Japanese Pediatric Guidelines for the Treatment and Management of Asthma 2008(JPGL2008)and the PRACTALL Consensus Report attach importance to respiratory viral infection as one of the risk and precipitating factors for asthma, as well as to allergens. This paper reviews the relationship between bronchiolitis caused by respiratory syncytial virus (RSV) and the occurrence of asthma, mainly describing the results of the author's group. In children with severe bronchiolitis caused by RSV infection, 1) Creola body-positive infants often develop asthma within 5 years; 2) When patients have a genetic impairment in the production of a Th1 cytokine IFN-γ, they often develop asthma; 3) Administration of a humanized anti-RS virus monoclonal antibody, palivizumab, suppresses recurrent wheezing in patients aged 3 years or younger. From the above results, early intervention for virus-induced asthma is considered necessary. Furthermore, attention is being paid to the results whether or not the prevention of severe bronchiolitis caused by RSV infection in children suppresses the occurrence of atopic asthma caused by mites peculiar to Japan.
