Sampling Methods

Asthma and other recurrent wheezing disorders, cystic fibrosis, acute respiratory distress syndrome, and chronic lung disease of prematurity are the most frequent pediatric disorders in which inflammatory processes within the airways play a crucial role (1-3). Although airway inflammation is of crucial pathogenetic importance in these diseases, because direct access to the airways is rarely possible, alternative markers of airway inflammation are needed for diagnostic and therapeutic purposes (Table 1). This article explores the use of biomarkers in peripheral blood and in urine (4, 5) as possible indirect measures to study airway inflammation (Table 2). In particular, the article focuses on the use of biomarkers, especially the use of eosinophil granule proteins in the blood and urine of children with asthma/wheezy bronchitis and cystic fibrosis, in comparison with healthy subjects.