NASOPHARYNGEAL EOSINOPHIL CATIONIC PROTEIN IN BRONCHIOLITIS - RELATION TO VIRAL FINDINGS AND SUBSEQUENT WHEEZING

A prospective 4-month follow-up of children hospitalized with bronchio litis revealed that high concentrations of eosinophil cationic protein (ECP) in nasopharyngeal aspirates (NPA) are predictive of wheezing af ter bronchiolitis. In the 29 patients who received no anti-inflammator y therapy the median concentration oi NPA ECP was 882 ng/g in those wi th physician-diagnosed wheezing and 154 ng/g in those without subseque nt physician-diagnosed wheezing (P = 0.02). The NPA ECP concentrations of the whole study group of 88 children with and without subsequent h ospital admissions for wheezing were 531 and 299 ng/g, respectively (P = 0.02). At entry the children with negative viral findings had signi ficantly higher concentrations of respiratory tract ECP than those wit h positive viral findings (515 vs. 240 ng/g; P = 0.01). The concentrat ion of ECP in respiratory secretions decreased significantly after bro nchiolitis (P = 0.01) provided that no new viral or mycoplasmal infect ion occurred. NPA ECP values decreased in relation to time regardless of whether anti-inflammatory therapy was used or not. Children with hi gh concentrations of respiratory tract ECP seemed to benefit from anti -inflammatory therapy with nebulized cromolyn sodium or budesonide; bo th drugs significantly decreased the number of subsequent physician-di agnosed bronchial obstructions (P = 0.0006), and they tended to decrea se the number of hospital admissions for wheezing (P = 0.08). Our resu lts suggest that high concentrations of ECP in respiratory tract secre tions in children with bronchiolitis reflect the presence of eosinophi lic inflammation also seen in asthma. (C) 1997 Wiley-Liss, Inc.