The most common lower respiratory tract infection in infants is bronchiolitis, which occurs in 21 percent of infants each year. The most common etiology is respiratory syncytial virus. Over the past few years, the number of hospitalizations for bronchiolitis has increased in the United States. One treatment for this disease consists of aerosolized ribavirin, an antiviral agent used for treatment of respiratory syncytial virus infections. Other treatments, geared toward symptom control, include bronchodilators and corticosteroids. However, there is little consensus regarding the best treatment strategies, and there is significant variation in treatments. King and associates performed a systematic review of the effectiveness of commonly used treatments for bronchiolitis in infants and children.

The research project was a systematic review of the scientific literature. The authors searched MEDLINE and Cochrane Collaboration’s Database of Controlled Clinical Trials for randomized controlled trials of the treatment of bronchiolitis from January 1980 through November 2002. Studies had to have a sample size of at least 10 subjects to be included in the review. Data extracted from the studies were characteristics of the study population, interventions used, and results. The results were entered into evidence tables and analyzed by drug category.

The researchers identified 797 abstracts, of which 44 met the inclusion criteria for the study. The studies were divided into the following categories of treatment: eight studies of epinephrine, 13 studies of beta₂-agonist bronchodilators, 13 studies of corticosteroids, and 10 studies of ribavirin. Most of the studies reviewed were powered insufficiently to detect statistically significant outcome differences between the study groups. There were few studies that collected outcomes data on matters important to clinicians and parents, such as the need for hospitalization and duration of stay.

The authors conclude that little evidence supports the routine use of any of these classes of medications in treating infants and children with bronchiolitis. They see a need for a large, well-designed study of the commonly used treatments for bronchiolitis to establish the best protocol for managing this condition.

editor’s note: As we move further in our attempt to develop an evidence-based approach to common medical problems, some of the old standard therapies are being reassessed, as is the case with the treatment of bronchiolitis. In another study published in the same issue, Mull and associates found that nebulized epinephrine and albuterol had similar efficacy in treating moderate bronchiolitis in young children.¹ The meaning for clinicians is that we need to continue to treat bronchiolitis with the standard medications and realize that eventually our treatment strategies may have to be altered.—k.e.m.