title: Can the use of HEPA cleaners in homes of asthmatic children and adolescents sensitized to cat and dog allergens decrease bronchial hyperresponsiveness and allergen contents in solid dust?
abstract: BACKGROUND
  Exposure and sensitization to pet allergens are associated with allergic asthma in children. Conflicting data have emerged regarding the potential benefit of air cleaners with respect to a reduction of indoor pet allergens and bronchial hyperresponsiveness (BHR).
  
  
  METHODS
  In a randomized controlled trial 36 asthmatic children with sensitization to cat and/or dog and significant exposure to cat and/or dog allergen (Fel d 1 and/or Can f 1 >500 ng/g of carpet dust) were included in order to study the effect of high-efficiency particulate arresting (HEPA) air cleaners placed in the living room and bedroom compared with the effect of sham air cleaners. Patients were allocated to two groups: group 1 exposed to active filters and group 2 exposed to sham filters. At month 0, after 6 months and after 12 months, pulmonary function testing and cold air challenge were performed, serum eosinophil cationic protein (ECP) and specific IgE to seven aeroallergens were determined, and carpet dust samples and filters were collected. Major pet allergen concentrations (Fel d 1, Can f 1) were determined in filters and bulk dust samples.
  
  
  RESULTS
  Thirty patients completed the study. After 6 and 12 months, there was no significant change in delta FEV(1) after cold air challenge, or in the use of medication and serum ECP levels. However, there was a trend in the active group towards an improvement of bronchial hyperresponsiveness, whereas the sham filter group showed a deterioration of BHR.
  
  
  CONCLUSIONS
  Although HEPA air cleaners retained airborne pet allergens, no effect on disease activity or allergen concentrations in bulk dust samples was observed in this study.
authors: Department of Pediatric Pneumology and Immunology, Charité Medical Centre, Berlin, Germany.
authors: Claudia
authors: C
authors: Sulser
authors: Gabriele
authors: G
authors: Schulz
authors: Petra
authors: P
authors: Wagner
authors: Christine
authors: C
authors: Sommerfeld
authors: Thomas
authors: T
authors: Keil
authors: Andreas
authors: A
authors: Reich
authors: Ulrich
authors: U
authors: Wahn
authors: Susanne
authors: S
authors: Lau
mesh_terms: D000293:Adolescent; D016902:Air Pollution, Indoor; D000485:Allergens / Q000032:analysis / Q000276:immunology*; D000818:Animals; D016535:Bronchial Hyperreactivity / Q000453:epidemiology / Q000276:immunology / Q000517:prevention & control*; D002415:Cats / Q000276:immunology; D002648:Child; D004285:Dogs / Q000276:immunology; D004391:Dust / Q000032:analysis / Q000276:immunology*; D004780:Environment, Controlled; D047150:Eosinophil Cationic Protein / Q000097:blood*; D005260:Female; D005374:Filtration / Q000295:instrumentation; D005541:Forced Expiratory Volume; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood*; D008297:Male
chemical_list: D000485:Allergens; D004391:Dust; D007073:Immunoglobulin E; D047150:Eosinophil Cationic Protein