title: Exhaled H(2)O(2) in steady-state bronchiectasis: relationship with cellular composition in induced sputum, spirometry, and extent and severity of disease.
abstract: OBJECTIVE
  To determine the concentration of exhaled H(2)O(2) in patients with bronchiectasis, and to study the relationship between levels of exhaled H(2)O(2), extent of disease, symptoms score, spirometry, and cellular composition obtained from induced sputum; furthermore, to account for possible confounding effects of inhaled corticosteroids (ICS) usage, long-term oral antibiotic treatment, and chronic colonization with Pseudomonas aeruginosa.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Thirty patients with steady-state bronchiectasis.
  
  
  RESULTS
  Mean (95% confidence interval [CI]) exhaled H(2)O(2) levels were significantly elevated in patients with bronchiectasis compared to normal subjects: 1.1 (0.87 to 1.29) microM vs 0.3 (0.19 to 0.36) microM, respectively (p < 0.0001). Patients treated with ICS had similar values as steroid-naïve patients. The group of patients with P aeruginosa colonization showed a significantly increased concentration of H(2)O(2) compared to the group without P aeruginosa colonization. Patients receiving long-term oral antibiotic treatment had significantly higher values of H(2)O(2) compared to those not receiving antibiotics. There was a significant positive correlation between H(2)O(2) and either the percentage of neutrophils in induced sputum or the extent of the disease as defined by high-resolution CT. A significant negative correlation was found between H(2)O(2) and FEV(1) percent predicted. Finally, there was a significant positive correlation between H(2)O(2) and the symptoms score.
  
  
  CONCLUSIONS
  Patients with bronchiectasis in stable condition showed increased levels of exhaled H(2)O(2). The above-mentioned levels were not decreased either by ICS or long-term oral antibiotic treatment, but were significantly affected by chronic colonization with P aeruginosa. H(2)O(2) levels could be an indirect index of neutrophilic inflammation, impairment of lung function, and extension and severity of the disease.
authors.affiliation: Department of Pneumonology, Athens Army General Hospital, Athens, Greece. ssat@hol.gr
authors.forename: Stelios
authors.initials: S
authors.lastname: Loukides
authors.forename: Demosthenes
authors.initials: D
authors.lastname: Bouros
authors.forename: Georgios
authors.initials: G
authors.lastname: Papatheodorou
authors.forename: Stephanos
authors.initials: S
authors.lastname: Lachanis
authors.forename: Panos
authors.initials: P
authors.lastname: Panagou
authors.forename: Nikolaos M
authors.initials: NM
authors.lastname: Siafakas
mesh_terms: D000280:Administration, Inhalation; D000284:Administration, Oral; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000009:adverse effects; D000328:Adult; D000730:Androstadienes / Q000008:administration & dosage / Q000009:adverse effects; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000009:adverse effects; D001944:Breath Tests; D001987:Bronchiectasis / Q000175:diagnosis* / Q000188:drug therapy; D019819:Budesonide / Q000008:administration & dosage / Q000009:adverse effects; D016001:Confidence Intervals; D005260:Female; D000068298:Fluticasone; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D006861:Hydrogen Peroxide / Q000032:analysis*; D007958:Leukocyte Count; D008134:Long-Term Care; D008297:Male; D008875:Middle Aged; D018410:Pneumonia, Bacterial / Q000175:diagnosis / Q000188:drug therapy; D011552:Pseudomonas Infections / Q000175:diagnosis / Q000188:drug therapy; D011550:Pseudomonas aeruginosa; D012307:Risk Factors; D013147:Spirometry; D013183:Sputum / Q000166:cytology*; D014797:Vital Capacity / Q000502:physiology
chemical_list: D000305:Adrenal Cortex Hormones; D000730:Androstadienes; D000900:Anti-Bacterial Agents; D019819:Budesonide; D006861:Hydrogen Peroxide; D000068298:Fluticasone