title: Increased leukotriene E4 in the exhaled breath condensate of children with mild asthma.
abstract: BACKGROUND
  Chronic airway inflammation is a feature of asthma. Increased levels of cysteinyl leukotrienes (cys-LTs; leukotriene [LT]C(4), LTD(4), LTE(4)) have been shown in the exhaled breath condensate (EBC) of children with moderate-to-severe asthma. The aim of this study was to examine the relationship between EBC cys-LTs (LTE(4)) levels and bronchial hyperreactivity in children with mild asthma in order to evaluate the clinical utility of measuring EBC cys-LTs levels.
  
  
  METHODS
  We measured LTE(4) levels in the EBC of children aged 8 to 18 years, including healthy nonasthmatic children (n = 6) and children with mild asthma (n = 37). Patients with mild asthma were classified into the following three groups: group 1, participants who had been asymptomatic (no wheezing/symptoms of asthma) for > 6 months prior to examination (n = 12); group 2, participants who were asymptomatic but had had wheezing/symptoms of asthma within 6 months before examination (n = 18); and group 3, patients with current wheeze and/or mild symptoms of asthma exacerbation at the time of examination.
  
  
  RESULTS
  Exhaled LTE(4) levels were increased in all children with mild asthma compared with nonasthmatic control subjects (5.69 +/- 9.62 pg/20 min vs 0.74 +/- 0.79 pg/20 min, p < 0.05) [mean +/- SD]. In particular, the EBC LTE(4) levels in group 2 (4.99 +/- 6.70 pg/20 min) and group 3 (14.66 +/- 17.11 pg/20 min) were increased compared with control subjects and group 1 (1.50 +/- 1.69 pg/20 min). The EBC LTE(4) levels negatively correlated with the provocative concentration of methacholine causing a 15% fall in FEV(1) (r = - 0.454, p = 0.012).
  
  
  CONCLUSIONS
  EBC cys-LTs may be useful as a noninvasive marker assessing airway inflammation and hyperreactivity in children with asthma.
authors.affiliation: Department of Pediatrics, The Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Shibata
authors.forename: Toshio
authors.initials: T
authors.lastname: Katsunuma
authors.forename: Morimitsu
authors.initials: M
authors.lastname: Tomikawa
authors.forename: Aiko
authors.initials: A
authors.lastname: Tan
authors.forename: Keisuke
authors.initials: K
authors.lastname: Yuki
authors.forename: Kenichi
authors.initials: K
authors.lastname: Akashi
authors.forename: Yoshikatsu
authors.initials: Y
authors.lastname: Eto
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000175:diagnosis*; D015415:Biomarkers / Q000032:analysis; D001944:Breath Tests; D016535:Bronchial Hyperreactivity / Q000175:diagnosis; D001985:Bronchial Provocation Tests; D002648:Child; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D017999:Leukotriene E4 / Q000032:analysis*; D008297:Male; D016210:Methacholine Chloride; D012016:Reference Values; D013223:Statistics as Topic
chemical_list: D015415:Biomarkers; D016210:Methacholine Chloride; D017999:Leukotriene E4