Symptomatic viral infection is associated with impaired response to treatment in children with acute asthma.

OBJECTIVE To examine the influence of viral respiratory infection (VRI) on treatment response in acute asthma in children. STUDY DESIGN A total of 218 children (mean age, 6.6 years) with acute asthma were recruited. Symptoms were recorded, an asthma severity score was determined, and whenever possible, a per-nasal aspirate was obtained for detection of viruses. Each child's response to inhaled β(2)-agonists was assessed after 6, 12, and 24 hours. RESULTS The 168 children with VRI symptoms received more treatment with inhaled β(2)-agonists after 6 hours (P = .010), 12 hours (P = .002), and 24 hours (P = .0005) compared with the 50 children without such symptoms. Asthma severity did not differ between the 2 groups. A per-nasal aspirate was obtained from 77% of the children. The most frequently identified virus was rhinovirus (61.4%). Among children with symptoms of a VRI, those with rhinovirus had an impaired response to β(2)-agonists at 6 hours (P = .032). CONCLUSION Children with acute asthma and symptoms of VRI respond less effectively to β(2)-agonists after 6, 12, or 24 hours and thus may benefit from more intense therapy and monitoring.