title: Patients with chronic obstructive pulmonary disease and chronically colonized with Haemophilus influenzae during stable disease phase have increased airway inflammation.
abstract: BACKGROUND
  Some patients with chronic obstructive pulmonary disease (COPD) show increased airway inflammation and bacterial colonization during stable phase. The aim of this study was to follow COPD patients and investigate chronic colonization with pathogenic bacteria during stable disease phase, and relate these findings to clinical parameters, inflammatory pattern, lung function, and exacerbations.
  
  
  METHODS
  Forty-three patients with COPD were included while in a stable state and followed up monthly until exacerbation or for a maximum of 6 months. The patients completed the Clinical COPD Questionnaire and Medical Research Council dyspnea scale questionnaires, and exhaled breath condensate was collected, followed by spirometry, impulse oscillometry, and sputum induction.
  
  
  RESULTS
  Ten patients were chronically colonized (ie, colonized at all visits) with Haemophilus influenzae during stable phase. These patients had higher sputum levels of leukotriene B4 (P<0.001), 8-isoprostane (P=0.002), myeloperoxidase activity (P=0.028), and interleukin-8 (P=0.02) during stable phase when compared with other patients. In addition, they had lower forced vital capacity (P=0.035) and reactance at 5 Hz (P=0.034), but there was no difference in forced expiratory volume in 1 second (FEV1), FEV1 % predicted, forced vital capacity % predicted, exhaled breath condensate biomarkers, C-reactive protein, or Clinical COPD Questionnaire and Medical Research Council dyspnea scale results. Three patients had intermittent colonization (colonized at only some visits) of H. influenzae during stable phase, and had lower levels of inflammatory biomarkers in sputum when compared with the chronically colonized patients. The difference in airway inflammation seen during stable phase in patients chronically colonized with H. influenzae was not observed during exacerbations.
  
  
  CONCLUSIONS
  Some COPD patients who were chronically colonized with H. influenzae during stable phase showed increased airway inflammation and reduced lung volumes when compared with non-chronically colonized patients.
authors.affiliation: Respiratory Medicine and Allergology, Department of Clinical Sciences, Lund University, Lund, Sweden.
authors.forename: Ellen
authors.initials: E
authors.lastname: Tufvesson
authors.affiliation: Respiratory Medicine and Allergology, Department of Clinical Sciences, Lund University, Lund, Sweden.
authors.forename: Leif
authors.initials: L
authors.lastname: Bjermer
authors.affiliation: Respiratory Medicine and Allergology, Department of Clinical Sciences, Lund University, Lund, Sweden.
authors.forename: Marie
authors.initials: M
authors.lastname: Ekberg
mesh_terms: D000368:Aged; D001944:Breath Tests; D018450:Disease Progression; D004417:Dyspnea / Q000453:epidemiology; D005260:Female; D005541:Forced Expiratory Volume; D006192:Haemophilus Infections / Q000175:diagnosis / Q000276:immunology / Q000382:microbiology* / Q000503:physiopathology; D006193:Haemophilus influenzae / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D018836:Inflammation Mediators / Q000276:immunology; D053208:Kaplan-Meier Estimate; D008168:Lung / Q000276:immunology / Q000382:microbiology* / Q000503:physiopathology; D008176:Lung Volume Measurements; D008297:Male; D008875:Middle Aged; D018410:Pneumonia, Bacterial / Q000175:diagnosis / Q000276:immunology / Q000382:microbiology* / Q000503:physiopathology; D011237:Predictive Value of Tests; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis / Q000276:immunology / Q000382:microbiology* / Q000503:physiopathology; D013147:Spirometry; D013183:Sputum / Q000276:immunology / Q000382:microbiology; D011795:Surveys and Questionnaires; D013997:Time Factors; D014797:Vital Capacity
chemical_list: D018836:Inflammation Mediators
keywords: biomarker; chronic obstructive pulmonary disease; colonization; inflammation; spirometry; sputum