Children with a history of RSV-bronchiolitis during infancy have an increased risk for developing asthma in childhood, which was independently associated with male gender, breast-feeding <3 months, living in a home environment with moisture damage and/or tobacco smoke by two or more residents and sensitization to at least one aeroallergen. Children with a history of RSV bronchiolitis in infancy had lower spirometry in comparison to matched control group. The difference was more marked for asthmatic ones but remained significant even for non-asthmatic children.

Although many children develop frequent infections, only a few have an underlying immune disorder. Children with dysfunction of the immune system develop frequent infections and/or recurrent, persistent, severe, and rare infections. The aim of this review is to provide to the clinician a valuable tool for recognizing any 'discords' of the 'immune-system symphonic orchestra'. By following a reverse route, it will be possible to brighten up the dark and winding road of immunodeficiencies and identify the exact point of immune dysfunction. This is fundamental and crucial to perceive etiologic management and subsequently achieve the best for these young patients and their families.