NO RELIABLE WAY EXISTS TO DIAGNOSE ASTHMA IN INFANTS AND TODDLERS. Recurrent wheezing, especially apart from colds, combined with physician-diagnosed eczema or atopic dermatitis, eosinophilia, and a parental history of asthma, increase the probability of a subsequent asthma diagnosis in the absence of other causes (strength of recommendation: B, 2 good-quality cohort studies).
Evidence summary
Wheezing in children is common and the differential diagnosis is broad. The many potential causes include upper respiratory infection, asthma, cystic fibrosis, foreign body aspiration, vascular ring, tracheomalacia, primary immunodeficiency, and congenital heart disease.1
Outpatient primary care cohort studies estimate that about half of children wheeze before they reach school age. Only one-third of children who wheeze during the first 3 years of life, however, continue to wheeze into later childhood and young adulthood.2-4
These findings have led some experts to suggest that not all wheezing in children is asthma and that asthma exists in variant forms.5-7 Variant wheezing patterns include transient early wheezing, which seems to be most prevalent in the first 3 years of life; wheezing without atopy, which occurs most often at 3 to 6 years of age; and wheezing with immunoglobulin E-associated atopy, which gradually increases in prevalence from birth and dominates in the over-6 age group. It is children in this last group whom we generally consider to have asthma.
Objective measures of lung function are challenging to perform in young children. Clinical signs and symptoms thus suggest the diagnosis of asthma.
Atopy, rhinitis, and eczema most often accompany persistent wheezing
Primary care cohort studies provide the best available evidence on which findings in infants and toddlers most likely predict persistent airway disease in childhood. A whole-population cohort study followed nearly all children born on the Isle of Wight from January 1989 through February 1990 to evaluate the natural history of childhood wheezing and to study associated risk factors.8 Children were seen at birth and at 1, 2, 4, and 10 years of age.
Findings most associated with current wheezing (within the last year) in 10-year-olds were atopy (odds ratio [OR]=4.38; 95% confidence interval [CI], 3.07-6.25), rhinitis (OR=3.72; 95% CI, 2.21-6.27), and eczema (OR=3.04; 95% CI, 2.05-4.51).8