title: Nasal and exhaled nitric oxide in allergic rhinitis.
abstract: OBJECTIVE
  The primary aim of this study was to assess whether one can use levels of nasal nitric oxide (nNO) and exhaled nitric oxide (eNO) as a means of evaluation in allergic rhinitis.
  
  
  METHODS
  We used a chemiluminescence analyzer to measure nNO and eNO in normal controls (n=34) and allergic rhinitis patients (n=35), and compared these measurements with various parameters of clinical symptoms and laboratory data.
  
  
  RESULTS
  Mean nNO (389±119 ppb) in allergic rhinitis patients was significantly higher than normal controls (276±88 ppb). Without asthma, mean eNO (64.8±55.9 ppb) in allergic rhinitis patients was significantly higher than normal controls (33.0±24.0 ppb). In the persistent allergic rhinitis group, eNO concentration was significantly higher, while nNO concentration was significantly lower than the intermittent group.
  
  
  CONCLUSIONS
  We can use nNO and eNO levels for evaluation of allergic rhinitis. However, we should consider the fact that nNO levels can be reduced, when symptoms are severe and long-lasting. Additionally, in allergic rhinitis, eNO can be elevated without asthma.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Hanyang University College of Medicine, Seoul, Korea.
authors.forename: Keon Jung
authors.initials: KJ
authors.lastname: Lee
authors.forename: Seok Hyun
authors.initials: SH
authors.lastname: Cho
authors.forename: Seung Hwan
authors.initials: SH
authors.lastname: Lee
authors.forename: Kyung
authors.initials: K
authors.lastname: Tae
authors.forename: Ho Joo
authors.initials: HJ
authors.lastname: Yoon
authors.forename: Sang Heon
authors.initials: SH
authors.lastname: Kim
authors.forename: Jin Hyeok
authors.initials: JH
authors.lastname: Jeong