The following scenario will doubtless be familiar to most Parkhurst Exchange readers. Mrs. Bureau arrives at your office because her 18-month-old son Jonathan has a “cold” and is “wheezing.” Three days ago, Jonathan developed a slight fever (38.4°C), and began sneezing and coughing. The night prior to his visit he seemed to have difficulty breathing and his mother heard him wheezing. When you imitate the sound of the wheeze to make certain she wasn’t confusing it with inspiratory stridor, she correctly identifies wheezing. On examination, Jonathan looks a little tired with a clear nasal discharge. He’s breathing at 50 bpm and you can hear the end-expiratory wheezing along with moist rhonchi. Post-tussive auscultation reveals wheezing is still present. You inquire further into the history: Jonathan attends daycare; he has no allergies; there’s no personal or family history of atopy, he hasn’t wheezed before. You diagnose him as an episodic viral wheezer. You give him 3 ventolin masks and his wheezing improves.
Unfortunately, there are few evidence-based treatments for the episodic viral wheezer. Guidelines suggest a short course of oral steroids (1-2 mg/kg/day) for 3-5 days, along with ventolin prn. Episodic viral wheezers aren’t asthmatics and don’t have the eosinophilic exudates in the airways associated with asthma. These are likely children with smaller airways that eventually enlarge with growth and subsequent cessation of wheezing. Although there is some support for giving steroids in the literature,1 two recent articles in the NEJM call into question the efficacy of both high-dose fluticasone and a short course of prednisolone.
Panickar2 recruited kids who presented at the emergency rooms of three English hospitals with viral-induced wheezing. There were 343 in the prednisolone group and 344 in the placebo group after randomization. The outcome measures were length of stay in hospital and PRAM (Pediatric Respiratory Assessment Measure) scores.3 After a 5-day course of either prednisolone or placebo, these authors found no difference between the two groups in either outcome measure.
Ducharme’s group4 looked at the efficacy of high-dose fluticasone (1,500 mcg/day) at the onset of a viral infection and continued for a maximum of 10 days. The primary outcome looked at whether the child subsequently required systemic steroids. Secondary outcomes looked at were symptoms, use of rescue medication, ER visits, hospitalizations and adverse events. This study also looked at issues around safety: changes in growth, bone mineral density and adrenal suppression. They recruited kids 1-6 years of age and tried to exclude atopic wheezers (those with allergic rhinitis, allergies to aeroallergens or elevated specific IgE). The children were followed for 6-12 months. The study did show that the treatment arm required fewer courses of rescue oral prednisolone than the placebo arm (8% vs 18%, odds ratio 0.49). The fluticasone group had shorter duration of symptoms and less use of rescue medication (ß2 agonist) during their viral infection. There were marked differences in growth between the two groups, however, with the fluticasone group falling behind significantly. There were no significant differences in the small number of children who had bone density studies completed or in cortisol levels. Based on the adverse effects on growth, these authors can’t recommend the use of high-dose fluticasone in the treatment of viral-induced wheezing.
These studies suggest that we need to change our practice. As the accompanying editorial suggests5 ß2 agonists should be given on a prn basis. Oral steroids should be reserved for hospitalized children who aren’t responding and are severely ill (this group might include truly atopic asthmatics). One of the difficulties is sorting out the truly episodic viral wheezer6 from the atopic wheezer. The latter, as all recent guidelines suggest,7 do benefit from continuous inhaled corticosteroids. Since viral-induced wheeze is more common in kids under 6 than true atopic asthma, we need much more work to ascertain the best method of treatment.
Richard Haber, MD, FAAP, FRCPC is an associate professor of pediatrics at McGill University and the Director of the Pediatric Consultation Centre at the Montreal Children’s Hospital.