title: Nitric oxide: a new concept in chronic sinusitis pathogenesis.
abstract: OBJECTIVE
  Exhaled NO is produced mainly in paranasal sinuses and nasal mucosa. Nasal NO has been suggested to have a variety of effects in nasal cavity. Decreased exhaled NO is found in chronic sinusitis, and NO metabolite levels are increased in animal models of chronic sinusitis, suggesting a role for them in sinusitis pathogenesis. There was no data available on human NO metabolite level.
  
  
  METHODS
  We lavaged maxillary sinuses in a control and 2 patient groups. The control group was patients who underwent functional endoscopic sinus surgery (FESS) due to any other reason than chronic sinusitis. The patient groups had chronic rhinosinusitis with and without polyposis who underwent FESS. Maxillary sinuses were lavaged during FESS, and NO metabolites (nitrate and nitrite) were lavaged in the lavage fluid.
  
  
  RESULTS
  Nitric oxide metabolite levels (mean +/- SEM) were 8.085 +/- 1.43 mumol/L in healthy maxillary sinus lavage fluid and 18.04 +/- 3.51 and 16.78 +/- 2.91 mumol/L in chronic rhinosinusitis with and without polyposis, respectively. Lavage fluid of sinuses with chronic sinusitis had elevated levels of NO metabolites, which were significantly higher than the control group. The difference between the chronic sinusitis with and without polyposis groups was not significant.
  
  
  CONCLUSIONS
  Nitric oxide metabolites were significantly higher in maxillary sinuses of patients with chronic sinusitis. Elevated levels of NO and NO metabolites in sinusitis might damage healthy sinus epithelium. NO metabolites may have an important role in sinusitis pathogenesis.
authors.affiliation: Iranian Rhinology Research Society, Department of Otorhinolaryngology, Head and Neck surgery & Otorhinolaryngology Research Center, Tehran University of Medical Sciences, Tehran, Iran. info@naraghi.ir
authors.forename: Mohsen
authors.initials: M
authors.lastname: Naraghi
authors.forename: Armin Farajzadeh
authors.initials: AF
authors.lastname: Deroee
authors.forename: MohammadReza
authors.initials: M
authors.lastname: Ebrahimkhani
authors.forename: Samira
authors.initials: S
authors.lastname: Kiani
authors.forename: AhmadReza
authors.initials: A
authors.lastname: Dehpour
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D016022:Case-Control Studies; D002908:Chronic Disease; D005260:Female; D006801:Humans; D008297:Male; D009079:Mucociliary Clearance; D009297:Nasal Mucosa / Q000378:metabolism / Q000503:physiopathology; D009569:Nitric Oxide / Q000378:metabolism*; D012852:Sinusitis / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology / Q000601:surgery