title: Effects of a leukotriene receptor antagonist on exhaled leukotriene E4 and prostanoids in children with asthma.
abstract: BACKGROUND
  Leukotriene (LT) E(4) and 8-isoprostane concentrations are elevated in exhaled breath condensate in children with asthma. The effects of leukotriene receptor antagonists (LTRAs) on exhaled leukotriene and prostanoids in children with asthma are unknown.
  
  
  OBJECTIVE
  (1) To study the effect of montelukast, a LTRA, on exhaled LTE(4), 8-isoprostane, and prostaglandin E(2) in children with asthma and atopic children; (2) to measure exhaled nitric oxide.
  
  
  METHODS
  An open-label study with oral montelukast (5 mg once daily for 4 weeks) was undertaken in 17 atopic children with asthma and 16 atopic children without asthma.
  
  
  RESULTS
  Pretreatment exhaled LTE(4) (P < .0001) and 8-isoprostane (P < .0001) values were higher in atopic children with asthma than in atopic children without asthma. In atopic children with asthma, montelukast reduced exhaled LTE(4) by 33% (P < .001), and this reduction was correlated with pretreatment LTE(4) values (r = -0.90; P = .0001). Posttreatment exhaled LTE(4) levels in children with asthma were higher than pretreatment LTE(4) values in atopic children without asthma (P < .004). Montelukast had no effect on exhaled LTE(4) in atopic children without asthma (P = .74), or on exhaled 8-isoprostane (atopic children with asthma, P = .94; atopic children without asthma, P = .55) and PGE(2) (atopic children with asthma, P = .56; atopic children without asthma, P = .93) in both groups. In atopic children with asthma, exhaled nitric oxide concentrations were reduced by 27% (P < .05) after montelukast.
  
  
  CONCLUSIONS
  Leukotriene receptor antagonists decrease exhaled LTE(4) in atopic children with asthma. This reduction is dependent on baseline exhaled LTE(4) values.
  
  
  CONCLUSIONS
  Measurement of exhaled LTE(4) might help identify children with asthma most likely to benefit from LTRAs.
authors.affiliation: Department of Pharmacology, Faculty of Medicine, Catholic University of the Sacred Heart, Largo F. Vito 1, 00168 Rome, Italy. pmontuschi@rm.unicatt.it
authors.forename: Paolo
authors.initials: P
authors.lastname: Montuschi
authors.forename: Chiara
authors.initials: C
authors.lastname: Mondino
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Koch
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Barnes
authors.forename: Giovanni
authors.initials: G
authors.lastname: Ciabattoni
mesh_terms: D000085:Acetates / Q000627:therapeutic use*; D000485:Allergens / Q000276:immunology; D018927:Anti-Asthmatic Agents / Q000627:therapeutic use*; D001249:Asthma / Q000188:drug therapy* / Q000276:immunology / Q000378:metabolism; D015415:Biomarkers / Q000032:analysis; D001944:Breath Tests; D002648:Child; D003430:Cross-Sectional Studies; D003521:Cyclopropanes; D015237:Dinoprost / Q000031:analogs & derivatives / Q000032:analysis; D015232:Dinoprostone / Q000032:analysis; D006801:Humans; D006967:Hypersensitivity / Q000175:diagnosis; D020024:Leukotriene Antagonists / Q000627:therapeutic use*; D017999:Leukotriene E4 / Q000032:analysis*; D009569:Nitric Oxide / Q000032:analysis*; D011804:Quinolines / Q000627:therapeutic use*; D012882:Skin Tests; D013147:Spirometry; D013440:Sulfides
chemical_list: D000085:Acetates; D000485:Allergens; D018927:Anti-Asthmatic Agents; D015415:Biomarkers; D003521:Cyclopropanes; D020024:Leukotriene Antagonists; D011804:Quinolines; D013440:Sulfides; C075750:8-epi-prostaglandin F2alpha; D009569:Nitric Oxide; D017999:Leukotriene E4; D015237:Dinoprost; D015232:Dinoprostone; C093875:montelukast