title: The effect of Pseudomonas aeruginosa infection on clinical parameters in steady-state bronchiectasis.
abstract: OBJECTIVE
  To investigate the effect of Pseudomonas aeruginosa infection on clinical parameters in Chinese patients with noncystic fibrosis and steady-state bronchiectasis.
  
  
  METHODS
  Prospective, cross-sectional clinicomicrobiological study with informed consent.
  
  
  METHODS
  Consecutive outpatient recruitment from a specialist bronchiectasis respiratory clinic.
  
  
  METHODS
  Outpatients (n = 100; 62 women; 55.1+/-16.7 years old; FEV1/FVC 1.4+/-0.7/2.1+/-0.9 L), who had stable respiratory symptoms for more than 3 weeks.
  
  
  RESULTS
  Respiratory pathogens isolated from the sputum were: Pseudomonas aeruginosa (33), Haemophilus influenzae (10), Moraxella catarrhalis (2), other Gram-negative bacilli (5), Streptococcus pneumoniae (6), Staphylococcus aureus (5), mycobacteria (3), and yeast (1). Clinical parameters in patients with positive isolation of P aeruginosa were compared with those without the organism in the sputum culture (non-P aeruginosa). In the P aeruginosa group, the FEV1/FVC ratio and sputum volume were lower (p < 0.005) and higher (p < 0.0001), respectively, than those of the non-P aeruginosa group. The FEV1/FVC ratio (< 60%) and sputum volume (grading > 5) were independently associated with a positive sputum isolation of P aeruginosa with odds ratios of 3.1 (confidence interval [CI] 1.2 to 8.4; p < 0.01) and 4.7 (CI 1.6 to 13.3; p < 0.001), respectively.
  
  
  CONCLUSIONS
  P aeruginosa is the predominant respiratory pathogen isolated in the sputum of Chinese patients with steady-state bronchiectasis, and its isolation is associated with high sputum output (> or = 75th quartile) and moderately severe airflow obstruction (FEV1/FVC < 60%).
authors.affiliation: University Department of Microbiology, Queen Mary Hospital, The University of Hong Kong, Hong Kong.
authors.forename: P L
authors.initials: PL
authors.lastname: Ho
authors.forename: K N
authors.initials: KN
authors.lastname: Chan
authors.forename: M S
authors.initials: MS
authors.lastname: Ip
authors.forename: W K
authors.initials: WK
authors.lastname: Lam
authors.forename: C S
authors.initials: CS
authors.lastname: Ho
authors.forename: K Y
authors.initials: KY
authors.lastname: Yuen
authors.forename: K W
authors.initials: KW
authors.lastname: Tsang
mesh_terms: D000328:Adult; D000368:Aged; D044466:Asian People; D001987:Bronchiectasis / Q000150:complications* / Q000208:ethnology / Q000382:microbiology*; D002681:China; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011552:Pseudomonas Infections / Q000150:complications* / Q000175:diagnosis / Q000208:ethnology; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification; D012129:Respiratory Function Tests; D013183:Sputum / Q000382:microbiology*