Published Online: August 13, 2014
Rhinovirus etiology of early wheezing (i.e. acute expiratory breathing difficulty) is of particular interest because of its strong association with recurrent wheezing and childhood asthma. The suggested explanations for this striking association are impaired viral defense, early airway inflammation, and genetic variation in rhinovirus-affected children. While no prior study has identified a subgroup of young wheezing children that benefits from systemic corticosteroids, they have not focused on rhinovirus etiology.
In a study recently published in The Journal of Allergy and Clinical Immunology (JACI), T. Jartti and colleagues present for the first-time a randomized controlled trial on the efficacy of a 3-day course of systemic corticosteroid in the treatment of the first rhinovirus-induced wheezing episode. They hypothesized that the administered systemic corticosteroid, prednisolone, decreases the risk of relapse in children in this patient group. The trial included 74 patients and was double-blinded throughout the 12-month follow-up.
Although no overall differences were found in the long-term primary outcomes, the investigators strikingly found that those with high rhinovirus load benefitted from prednisolone in terms of less risk of physician-confirmed recurrence within 2 and 12 months. Interestingly, they also found differences in the short-term secondary outcomes: the prednisolone group had less cough, rhinitis, noisy breathing, and severe breathing difficulties, as well as fewer nocturnal respiratory symptoms at home within 2 weeks.
The investigators concluded that prednisolone treatment cannot be routinely recommended for all children experiencing a first acute moderate-to-severe rhinovirus-induced wheezing episode since they were not able to show an effect in the primary outcomes. However, the results suggest that the prednisolone treatment is beneficial in a sub-group of young children with high viral loads at presentation. The apparent effect of prednisolone in long-term outcomes among children with high rhinovirus load, coupled with the benefits in most short-term outcomes warrant further study.
Clinically, the challenge is the early identification of children at high risk of asthma, and subsequently providing them with effective intervention to reduce respiratory morbidity. Rhinovirus etiology of early wheezing is a promising new marker for these high-risk children. The findings support a role for high rhinovirus load as an important marker of those children with early pulmonary inflammation, which may benefit from acute treatment with prednisolone.
The Journal of Allergy and Clinical Immunology (JACI) is an official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.