Most wheezing in young children is due to viral infection of the airways, often termed bronchiolitis. A common cause would be Respiratory Syncitial Virus which you may have heard of as RSV. Essentially all wheezing below the age of 3 and most wheezing between the ages of 3 and 6 falls into this category. The wheezing produced by these infections results from damage and swelling of the airways as a direct result of the viral infection. Traditionally, kids with bad wheezing from such infections have been given steroids to try and reduce the swelling and inflammation.
This week’s New England Journal of Medicine has two interesting studies examining this practice. In the first kids with viral induced wheezing who were sick enough to be hospitalized were randomly given either prednisone or placebo. As it turns out there was no difference in the length of hospital stay or any other outcome between the two groups. In the second study, kids between the ages of 1 and 6 who had strictly viral induced wheezing were given inhaled steroids at the start of an upper respiratory infection to try and prevent wheezing. In this study, inhaled steroids were no better than placebo at preventing viral induced wheezing.
These studies will likely lead to a significant change in the treatment of viral induced wheezing. I would like to stress that these studies do not examine the effects of steroids on asthma or viral induced asthma exacerbations.