title: Increased eosinophilic cationic protein in nasal fluid in hospitalized wheezy infants with RSV infection.
abstract: BACKGROUND
  Respiratory syncytial virus (RSV) is a major respiratory pathogen which causes bronchiolitis with dyspnea and wheezing in children less than 2 years old. RSV bronchiolitis in infancy severe enough to cause hospitalization might be a risk factor for allergic sensitization and bronchial asthma in future. However, the pathophysiology behind this development has not been clearly characterized. To evaluate the existence of airway inflammation and characteristic of RSV bronchiolitis, we analyzed and compared the concentrations of eosinophilic cationic protein (ECP) in nasal fluid and plasma.
  
  
  METHODS
  From 69 infants (aged <2 years) hospitalized for possible lower respiratory tract infections including RSV infection, we collected nasal fluid and plasma and determined the ECP concentrations.
  
  
  RESULTS
  ECP concentrations in nasal fluid were significantly higher in patients with wheezing and/or bronchial rales than in patients without them (1733 ± 660 ng/mL vs 680 ± 450 ng/mL, p = 0.018), and those of the respiratory syncitial virus-infected group were significantly higher than those of the uninfected group (p = 0.04). Meanwhile, there was no significant difference in plasma ECP levels between patients with wheezing and patients without wheezing, and no significant difference between RSV-infected and other pathogen-infected patients. There were significant correlations between nasal fluid ECP concentrations and both neutrophil and eosinophil counts in the peripheral blood.
  
  
  CONCLUSIONS
  Nasal fluid ECP concentrations are increased in infants with lower respiratory infections including RSV infection accompanied with wheezing. ECP probably originates from neutrophils as well as eosinophils migrated into airways. The monitoring of ECP concentration in nasal fluid may be useful for evaluating leukocyte (including eosinophils and neutrophils)-mediated airway inflammation during infancy and its severity.
authors.affiliation: Department of Pediatrics, National Hospital Organization, Fukuyama Medical Center, Hiroshima, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Okamoto
authors.forename: Masanori
authors.initials: M
authors.lastname: Ikeda
authors.forename: Masato
authors.initials: M
authors.lastname: Okuda
authors.forename: Tomoko
authors.initials: T
authors.lastname: Sakamoto
authors.forename: Mizue
authors.initials: M
authors.lastname: Takasugi
authors.forename: Nobumasa
authors.initials: N
authors.lastname: Takahashi
authors.forename: Toru
authors.initials: T
authors.lastname: Araki
authors.forename: Tsuneo
authors.initials: T
authors.lastname: Morishima
authors.forename: Kozo
authors.initials: K
authors.lastname: Yasui
mesh_terms: D047150:Eosinophil Cationic Protein / Q000032:analysis*; D005260:Female; D006760:Hospitalization; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D017817:Nasal Lavage Fluid / Q000276:immunology*; D012135:Respiratory Sounds / Q000209:etiology* / Q000276:immunology; D018357:Respiratory Syncytial Virus Infections / Q000276:immunology*; D013997:Time Factors
chemical_list: D047150:Eosinophil Cationic Protein