title: Reference ranges for induced sputum eosinophil counts in Korean adult population.
abstract: BACKGROUND
  Induced sputum analyses are widely utilized to evaluate airway inflammation in asthmatics. However, the values have not been examined in Korean adults.
  
  
  OBJECTIVE
  The purpose of this study is to determine reference ranges for induced sputum eosinophils and their influencing factors in Korean adults.
  
  
  METHODS
  A total of 208 healthy nonasthmatic adults were recruited. Sputum induction and processing followed the international standard protocols.
  
  
  RESULTS
  Adequate sputum samples were successfully collected from 81 subjects (38.9%). The upper 90 percentile for sputum eosinophil was calculated as 3.5%. The median value of eosinophil count percentage was significantly higher in subjects with atopy than those without atopy (median, 1.6%; range, 0-11.0% vs. median, 0%; range 0-3.6%, p=0.030). However, no significant correlations were found with age, gender, body mass index, smoking status, blood eosinophil, or fractional exhaled nitric oxide levels.
  
  
  CONCLUSIONS
  Current study was the first attempt to determine the reference ranges of induced sputum eosinophils in Korean adults. The cutoff value for sputum eosinophilia was 3.5%, and was significantly associated with atopy.
authors.affiliation: Department of Internal Medicine, Inje University Busan Paik Hospital, Inje University College of Medicine, Busan 614-735, Korea. ; Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul 110-799, Korea.
authors.forename: Mi-Yeong
authors.initials: MY
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Pusan National University College of Medicine, Busan 626-870, Korea.
authors.forename: Eun-Jung
authors.initials: EJ
authors.lastname: Jo
authors.affiliation: Department of Internal Medicine, Pusan National University Yangsan Hospital, Yangsan 626-700, Korea.
authors.forename: Seung-Eun
authors.initials: SE
authors.lastname: Lee
authors.affiliation: Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul 110-799, Korea. ; Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-799, Korea. ; Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam 463-707, Korea.
authors.forename: Suh-Young
authors.initials: SY
authors.lastname: Lee
authors.affiliation: Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul 110-799, Korea. ; Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-799, Korea.
authors.forename: Woo-Jung
authors.initials: WJ
authors.lastname: Song
authors.affiliation: Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul 110-799, Korea. ; Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-799, Korea.
authors.forename: Tae-Wan
authors.initials: TW
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Korea University College of Medicine, Seoul 136-705, Korea.
authors.forename: Gyu-Young
authors.initials: GY
authors.lastname: Hur
authors.affiliation: Department of Internal Medicine, Eulji General Hospital, Eulji University School of Medicine, Seoul 139-711, Korea.
authors.forename: Jae-Hyung
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul 138-736, Korea.
authors.forename: Tae-Bum
authors.initials: TB
authors.lastname: Kim
authors.affiliation: Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul 110-799, Korea. ; Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-799, Korea.
authors.forename: Heung-Woo
authors.initials: HW
authors.lastname: Park
authors.affiliation: Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul 110-799, Korea. ; Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-799, Korea. ; Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam 463-707, Korea.
authors.forename: Yoon-Seok
authors.initials: YS
authors.lastname: Chang
authors.affiliation: Department of Allergy and Clinical Immunology, Ajou University School of Medicine, Suwon 443-721, Korea.
authors.forename: Hae-Sim
authors.initials: HS
authors.lastname: Park
authors.affiliation: Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul 110-799, Korea. ; Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-799, Korea.
authors.forename: Kyung-Up
authors.initials: KU
authors.lastname: Min
authors.affiliation: Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul 110-799, Korea. ; Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-799, Korea.
authors.forename: Sang-Heon
authors.initials: SH
authors.lastname: Cho
keywords: Eosinophils; Healthy volunteers; Reference values; Sputum
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