title: Urinary cysteinyl leukotriene E4 level and therapeutic response to montelukast in children with mild obstructive sleep apnea.
abstract: BACKGROUND
  Antileukotriene has been used for alleviating disease severity in children with adenotonsillar hypertrophy (ATH) and mild obstructive sleep apnea (OSA). Previous study showed the relationship between urinary cysteinyl leukotriene E₄ (uLTE₄) level and therapeutic response to montelukast in asthmatic adults. However, this relationship has never been investigated in pediatric OSA.
  
  
  OBJECTIVE
  To determine the relationship between uLTE₄ level and therapeutic response to montelukast in children with ATH and mild OSA.
  
  
  METHODS
  Children aged 3-15 yrs who had ATH and mild OSA were enrolled. All had quality of life (assessed by Thai version OSA-18 QoL questionnaire) and uLTE₄ levels measured prior to start a 6-week course of montelukast treatment. Overnight polysomnography (PSG) and QoL reassessment were performed after completing the treatment. Those who demonstrated a large improvement of mean total QoL score or ≥ 50% decrease of obstructive apnea-hypopnea index (OAHI) after the treatment were defined as responders.
  
  
  RESULTS
  Twenty-six children were enrolled (mean age 7.5 ± 2.9 yrs, 38.5% male). After 6-week course of montelukast, nine (34.6%) children showed significant improvement. The mean uLTE₄ level from the responders was higher comparing to the non-responders (2,952.56 ± 966.9 vs. 978.6 ± 460.8 pg/mg creatinine; p < 0.001). uLTE₄ level of ≥ 1,457 pg/mg creatinine had 100% sensitivity and 88.2% specificity in identifying the responders.
  
  
  CONCLUSIONS
  We found the association between ULTE4 and therapeutic response to monteleukast. The uLTE₄ level of ≥ 1,457 pg/mg creatinine could predict the therapeutic response to montelukast in children who had ATH and mild OSA.
authors.affiliation: Division of Pulmonology and Critical Care.
authors.forename: Kanokkarn
authors.initials: K
authors.lastname: Sunkonkit
authors.affiliation: Division of Pulmonology and Critical Care.
authors.forename: Suchada
authors.initials: S
authors.lastname: Sritippayawan
authors.affiliation: Division of Neurology, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
authors.forename: Montida
authors.initials: M
authors.lastname: Veeravikrom
authors.affiliation: Division of Pulmonology and Critical Care.
authors.forename: Jitladda
authors.initials: J
authors.lastname: Deerojanawong
authors.affiliation: Division of Pulmonology and Critical Care.
authors.forename: Nuanchan
authors.initials: N
authors.lastname: Prapphal
mesh_terms: D000085:Acetates / Q000627:therapeutic use*; D000293:Adolescent; D018927:Anti-Asthmatic Agents / Q000627:therapeutic use*; D054316:Biomarkers, Pharmacological / Q000652:urine*; D002648:Child; D002675:Child, Preschool; D003404:Creatinine / Q000097:blood; D003521:Cyclopropanes; D018450:Disease Progression; D005260:Female; D006801:Humans; D017999:Leukotriene E4 / Q000652:urine*; D008297:Male; D011237:Predictive Value of Tests; D011379:Prognosis; D011804:Quinolines / Q000627:therapeutic use*; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis / Q000188:drug therapy*; D013440:Sulfides
chemical_list: D000085:Acetates; D018927:Anti-Asthmatic Agents; D054316:Biomarkers, Pharmacological; D003521:Cyclopropanes; D011804:Quinolines; D013440:Sulfides; D017999:Leukotriene E4; D003404:Creatinine; C093875:montelukast