The Role of IgE in Pediatric Asthma

Asthma is a complex multifactorial disease in which allergic sensitization plays an essential role. Sensitivity to indoor allergens is associated with prevalence, severity, and exacerbations of asthma, while exposure to outdoor allergens initiates exacerbations (1,2). A trait for an elevated level of serum IgE is coinherited with bronchial hyperresponsiveness. Thus, there is a second link between IgE and airway inflammation that appears to be independent of specific allergic susceptibility (3). 

Serum IgE levels correlate with the severity of clinical manifestations of asthma (4,5). During childhood total serum IgE appears to track with age. Infants less than one year old with high serum IgE continue to have elevated levels at 6 and 11 (6) (Fig. 1). These children are predisposed to persistent wheezing and early sensitization to aeroallergens. Others, with wheezing only during the first year of life and not later, have serum IgE concentrations similar to those of nonwheezing children. 

Wheezy infants who will have asthma are difficult to distinguish from others whose symptoms will be transient. A vast majority of all cases of asthma have their onset in the first years of life (7), but no more than a minority of 

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One feature of asthma that appears to be particularly important is the thickening of the basement membrane of the airway epithelium and the deposition of collagen and other matrix products in the airway wall. It has been suggested that these changes constitute the basis for remodeling of the airway, a process that may predispose to airway hyperresponsiveness and to the development of chronic, persistent asthma symptoms. Thus, therapeutic strategies for wheezy infants must address the possibility that for those who will go on to develop asthma, a prolonged delay in anti-inflammatory treatment leads to permanent loss in pulmonary function. 

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