Background: The importance of the inflammatory response in allergic disease has warranted investigation of two of the more integral cells in the pathogenesis of allergic rhinitis, namely, nasal basophilic cells (NBCs) and nasal eosinophils (NEs). In the present study the natural history of NBCs and NEs was studied from birth through 4 years of age in infants of atopic parents to better understand their relationship to the development of various atopic disorders.
Methods: During a prospective, randomized, controlled trial of the effect of maternal and infant food avoidance on the development of atopic disorders in 288 infants of atopic parents, NBCs and NEs were determined semiquantitatively on Wright-Geimsa stained nasal mucosal scrapings and related to each other and to various atopic parameters.
Results: In these infants who are at high risk NBCs developed in both those becoming atopic and those remaining nonatopic, but they occurred with increased frequency and quantity in those children in whom most allergic disorders and food or inhalant sensitization developed. NEs, rare at 4 months in all infants, increased in atopic children from 1 to 4 years, and remained infrequent and nominal in nonatopic children. Levels of NBCs and NEs (1) correlated with each other strongly, directly, and with increasing magnitude in children from ages 4 months to 4 years and (2) correlated with log serum IgE levels weakly and moderately in children from ages 2 to 4 years. Stepwise linear regression analyses revealed that allergic rhinitis accounted for most of the variance seen in the level of NBCs and NEs during early childhood, reaching 50% by age 4 years. Asthma, atopic dermatitis, food allergy, food and inhalant sensitization, serum IgE level, and IgG beta-lactoglobulin level accounted for a small proportion of the variance in NBCs and NEs from ages 4 months to 4 years.
Conclusions: These findings help to elucidate the natural history of NBCs and NEs in infants at risk for atopic disorders and document the temporal association of these cells with the development of atopic disease, principally allergic rhinitis.