title: Randomized trial to evaluate azithromycin's effects on serum and upper airway IL-8 levels and recurrent wheezing in infants with respiratory syncytial virus bronchiolitis.
abstract: BACKGROUND
  Respiratory syncytial virus (RSV) bronchiolitis in infancy is a major risk factor for recurrent wheezing and asthma. Because azithromycin attenuated neutrophilic airway inflammation in a murine viral bronchiolitis model, demonstration of similar effects in human subjects might provide a strategy for the prevention of postbronchiolitis recurrent wheezing.
  
  
  OBJECTIVE
  We sought to investigate whether azithromycin treatment during RSV bronchiolitis reduces serum and nasal lavage IL-8 levels and the occurrence of postbronchiolitis recurrent wheezing.
  
  
  METHODS
  We performed a randomized, double-masked, placebo-controlled proof-of-concept trial in 40 otherwise healthy infants hospitalized with RSV bronchiolitis who were treated with azithromycin or placebo for 14 days. IL-8 levels were measured in nasal lavage fluid and serum on randomization, day 8, and day 15 (nasal lavage only). The occurrence of wheezing episodes was assessed monthly over the ensuing 50 weeks.
  
  
  RESULTS
  Compared with placebo, azithromycin treatment did not reduce serum IL-8 levels at day 8 (P = .6) but resulted in a greater decrease in nasal lavage fluid IL-8 levels by day 15 (P = .03). Twenty-two percent of azithromycin-treated participants experienced at least 3 wheezing episodes compared with 50% of participants in the placebo group (P = .07). Azithromycin treatment resulted in prolonged time to the third wheezing episode (P = .048) and in fewer days with respiratory symptoms over the subsequent year in comparison with placebo (36.7 vs 70.1 days, P = .01).
  
  
  CONCLUSIONS
  In this proof-of-concept study azithromycin treatment during RSV bronchiolitis reduced upper airway IL-8 levels, prolonged the time to the third wheezing episode, and reduced overall respiratory morbidity over the subsequent year.
authors.affiliation: Division of Allergy, Immunology and Pulmonary Medicine, Department of Pediatrics, Washington University School of Medicine and St Louis Children's Hospital, St Louis, Mo. Electronic address: beigelman_a@kids.wustl.edu.
authors.forename: Avraham
authors.initials: A
authors.lastname: Beigelman
authors.affiliation: Division of Allergy, Immunology and Pulmonary Medicine, Department of Pediatrics, Washington University School of Medicine and St Louis Children's Hospital, St Louis, Mo.
authors.forename: Megan
authors.initials: M
authors.lastname: Isaacson-Schmid
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine and St Louis Children's Hospital, St Louis, Mo.
authors.forename: Geneline
authors.initials: G
authors.lastname: Sajol
authors.affiliation: Division of Biostatistics, Washington University School of Medicine and St Louis Children's Hospital, St Louis, Mo.
authors.forename: Jack
authors.initials: J
authors.lastname: Baty
authors.affiliation: Division of Allergy, Immunology and Pulmonary Medicine, Department of Pediatrics, Washington University School of Medicine and St Louis Children's Hospital, St Louis, Mo.
authors.forename: Oscar M
authors.initials: OM
authors.lastname: Rodriguez
authors.affiliation: Division of Allergy, Immunology and Pulmonary Medicine, Department of Pediatrics, Washington University School of Medicine and St Louis Children's Hospital, St Louis, Mo.
authors.forename: Erin
authors.initials: E
authors.lastname: Leege
authors.affiliation: Division of Allergy, Immunology and Pulmonary Medicine, Department of Pediatrics, Washington University School of Medicine and St Louis Children's Hospital, St Louis, Mo.
authors.forename: Kevin
authors.initials: K
authors.lastname: Lyons
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine and St Louis Children's Hospital, St Louis, Mo.
authors.forename: Toni L
authors.initials: TL
authors.lastname: Schweiger
authors.affiliation: Division of Biostatistics, Washington University School of Medicine and St Louis Children's Hospital, St Louis, Mo.
authors.forename: Jie
authors.initials: J
authors.lastname: Zheng
authors.affiliation: Division of Biostatistics, Washington University School of Medicine and St Louis Children's Hospital, St Louis, Mo.
authors.forename: Kenneth B
authors.initials: KB
authors.lastname: Schechtman
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine and St Louis Children's Hospital, St Louis, Mo.
authors.forename: Mario
authors.initials: M
authors.lastname: Castro
authors.affiliation: Division of Allergy, Immunology and Pulmonary Medicine, Department of Pediatrics, Washington University School of Medicine and St Louis Children's Hospital, St Louis, Mo.
authors.forename: Leonard B
authors.initials: LB
authors.lastname: Bacharier
mesh_terms: D017963:Azithromycin / Q000008:administration & dosage / Q000627:therapeutic use*; D001990:Bronchiolitis, Viral / Q000097:blood / Q000150:complications / Q000188:drug therapy* / Q000378:metabolism*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D016209:Interleukin-8 / Q000097:blood / Q000378:metabolism*; D008297:Male; D017817:Nasal Lavage Fluid; D012135:Respiratory Sounds / Q000187:drug effects* / Q000209:etiology; D018357:Respiratory Syncytial Virus Infections / Q000097:blood / Q000150:complications / Q000188:drug therapy* / Q000378:metabolism*; D018113:Respiratory Syncytial Virus, Human; D012307:Risk Factors; D016896:Treatment Outcome
chemical_list: D016209:Interleukin-8; D017963:Azithromycin
keywords: Azithromycin; IL-8; respiratory syncytial virus; wheezing