title: Predicting the presence of bacterial pathogens in the airways of primary care patients with acute cough.
abstract: BACKGROUND
  Bacterial testing of all patients who present with acute cough is not feasible in primary care. Furthermore, the extent to which easily obtainable clinical information predicts bacterial infection is unknown. We evaluated the diagnostic value of clinical examination and testing for C-reactive protein and procalcitonin for bacterial lower respiratory tract infection.
  
  
  METHODS
  Through a European diagnostic study, we recruited 3104 adults with acute cough (≤ 28 days) in primary care settings. All of the patients underwent clinical examination, measurement of C-reactive protein and procalcitonin in blood, and chest radiography. Bacterial infection was determined by conventional culture, polymerase chain reaction and serology, and positive results were defined by the presence ofStreptococcus pneumoniae,Haemophilus influenzae,Mycoplasma pneumoniae,Bordetella pertussisorLegionella pneumophila. Using multivariable regression analysis, we examined the association of diagnostic variables with the presence of bacterial infection.
  
  
  RESULTS
  Overall, 539 patients (17%) had bacterial lower respiratory tract infection, and 38 (1%) had bacterial pneumonia. The only item with diagnostic value for lower respiratory tract infection was discoloured sputum (area under the receiver operating characteristic [ROC] curve 0.56, 95% confidence interval [CI] 0.54-0.59). Adding C-reactive protein above 30 mg/L increased the area under the ROC curve to 0.62 (95% CI 0.59-0.65). For bacterial pneumonia, comorbidity, fever and crackles on auscultation had diagnostic value (area under ROC curve 0.68, 95% CI 0.58-0.77). Adding C-reactive protein above 30 mg/L increased the area under the ROC curve to 0.79 (95% CI 0.71-0.87). Procalcitonin did not add diagnostic information for any bacterial lower respiratory tract infection, including bacterial pneumonia.
  
  
  CONCLUSIONS
  In adults presenting with acute lower respiratory tract infection, signs, symptoms and C-reactive protein showed diagnostic value for a bacterial cause. However, the ability of these diagnostic indicators to exclude a bacterial cause was limited. Procalcitonin added no clinically relevant information.
authors: Julius Center for Health Sciences and Primary Care (Teepe, Broekhuizen, Verheij), University Medical Center Utrecht, Utrecht, The Netherlands; Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute (VAXINFECTIO) (Loens, Lammens, Ieven, Goossens, Coenen), and Centre for General Practice, Primary and Interdisciplinary Care (Coenen), University of Antwerp, Antwerp, Belgium; Primary Care Medical Group (Little), University of Southampton Medical School, Southampton, UK; Nuffield Department of Primary Care Health Sciences (Butler), University of Oxford, Oxford, UK; Faculty of Health Sciences (Godycki-Cwirko), Medical University of Lodz, Lodz, Poland j.teepe-2@umcutrecht.nl.
authors: Jolien
authors: J
authors: Teepe
authors: Julius Center for Health Sciences and Primary Care (Teepe, Broekhuizen, Verheij), University Medical Center Utrecht, Utrecht, The Netherlands; Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute (VAXINFECTIO) (Loens, Lammens, Ieven, Goossens, Coenen), and Centre for General Practice, Primary and Interdisciplinary Care (Coenen), University of Antwerp, Antwerp, Belgium; Primary Care Medical Group (Little), University of Southampton Medical School, Southampton, UK; Nuffield Department of Primary Care Health Sciences (Butler), University of Oxford, Oxford, UK; Faculty of Health Sciences (Godycki-Cwirko), Medical University of Lodz, Lodz, Poland.
authors: Berna D L
authors: BDL
authors: Broekhuizen
authors: Julius Center for Health Sciences and Primary Care (Teepe, Broekhuizen, Verheij), University Medical Center Utrecht, Utrecht, The Netherlands; Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute (VAXINFECTIO) (Loens, Lammens, Ieven, Goossens, Coenen), and Centre for General Practice, Primary and Interdisciplinary Care (Coenen), University of Antwerp, Antwerp, Belgium; Primary Care Medical Group (Little), University of Southampton Medical School, Southampton, UK; Nuffield Department of Primary Care Health Sciences (Butler), University of Oxford, Oxford, UK; Faculty of Health Sciences (Godycki-Cwirko), Medical University of Lodz, Lodz, Poland.
authors: Katherine
authors: K
authors: Loens
authors: Julius Center for Health Sciences and Primary Care (Teepe, Broekhuizen, Verheij), University Medical Center Utrecht, Utrecht, The Netherlands; Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute (VAXINFECTIO) (Loens, Lammens, Ieven, Goossens, Coenen), and Centre for General Practice, Primary and Interdisciplinary Care (Coenen), University of Antwerp, Antwerp, Belgium; Primary Care Medical Group (Little), University of Southampton Medical School, Southampton, UK; Nuffield Department of Primary Care Health Sciences (Butler), University of Oxford, Oxford, UK; Faculty of Health Sciences (Godycki-Cwirko), Medical University of Lodz, Lodz, Poland.
authors: Christine
authors: C
authors: Lammens
authors: Julius Center for Health Sciences and Primary Care (Teepe, Broekhuizen, Verheij), University Medical Center Utrecht, Utrecht, The Netherlands; Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute (VAXINFECTIO) (Loens, Lammens, Ieven, Goossens, Coenen), and Centre for General Practice, Primary and Interdisciplinary Care (Coenen), University of Antwerp, Antwerp, Belgium; Primary Care Medical Group (Little), University of Southampton Medical School, Southampton, UK; Nuffield Department of Primary Care Health Sciences (Butler), University of Oxford, Oxford, UK; Faculty of Health Sciences (Godycki-Cwirko), Medical University of Lodz, Lodz, Poland.
authors: Margareta
authors: M
authors: Ieven
authors: Julius Center for Health Sciences and Primary Care (Teepe, Broekhuizen, Verheij), University Medical Center Utrecht, Utrecht, The Netherlands; Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute (VAXINFECTIO) (Loens, Lammens, Ieven, Goossens, Coenen), and Centre for General Practice, Primary and Interdisciplinary Care (Coenen), University of Antwerp, Antwerp, Belgium; Primary Care Medical Group (Little), University of Southampton Medical School, Southampton, UK; Nuffield Department of Primary Care Health Sciences (Butler), University of Oxford, Oxford, UK; Faculty of Health Sciences (Godycki-Cwirko), Medical University of Lodz, Lodz, Poland.
authors: Herman
authors: H
authors: Goossens
authors: Julius Center for Health Sciences and Primary Care (Teepe, Broekhuizen, Verheij), University Medical Center Utrecht, Utrecht, The Netherlands; Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute (VAXINFECTIO) (Loens, Lammens, Ieven, Goossens, Coenen), and Centre for General Practice, Primary and Interdisciplinary Care (Coenen), University of Antwerp, Antwerp, Belgium; Primary Care Medical Group (Little), University of Southampton Medical School, Southampton, UK; Nuffield Department of Primary Care Health Sciences (Butler), University of Oxford, Oxford, UK; Faculty of Health Sciences (Godycki-Cwirko), Medical University of Lodz, Lodz, Poland.
authors: Paul
authors: P
authors: Little
authors: Julius Center for Health Sciences and Primary Care (Teepe, Broekhuizen, Verheij), University Medical Center Utrecht, Utrecht, The Netherlands; Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute (VAXINFECTIO) (Loens, Lammens, Ieven, Goossens, Coenen), and Centre for General Practice, Primary and Interdisciplinary Care (Coenen), University of Antwerp, Antwerp, Belgium; Primary Care Medical Group (Little), University of Southampton Medical School, Southampton, UK; Nuffield Department of Primary Care Health Sciences (Butler), University of Oxford, Oxford, UK; Faculty of Health Sciences (Godycki-Cwirko), Medical University of Lodz, Lodz, Poland.
authors: Chris C
authors: CC
authors: Butler
authors: Julius Center for Health Sciences and Primary Care (Teepe, Broekhuizen, Verheij), University Medical Center Utrecht, Utrecht, The Netherlands; Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute (VAXINFECTIO) (Loens, Lammens, Ieven, Goossens, Coenen), and Centre for General Practice, Primary and Interdisciplinary Care (Coenen), University of Antwerp, Antwerp, Belgium; Primary Care Medical Group (Little), University of Southampton Medical School, Southampton, UK; Nuffield Department of Primary Care Health Sciences (Butler), University of Oxford, Oxford, UK; Faculty of Health Sciences (Godycki-Cwirko), Medical University of Lodz, Lodz, Poland.
authors: Samuel
authors: S
authors: Coenen
authors: Julius Center for Health Sciences and Primary Care (Teepe, Broekhuizen, Verheij), University Medical Center Utrecht, Utrecht, The Netherlands; Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute (VAXINFECTIO) (Loens, Lammens, Ieven, Goossens, Coenen), and Centre for General Practice, Primary and Interdisciplinary Care (Coenen), University of Antwerp, Antwerp, Belgium; Primary Care Medical Group (Little), University of Southampton Medical School, Southampton, UK; Nuffield Department of Primary Care Health Sciences (Butler), University of Oxford, Oxford, UK; Faculty of Health Sciences (Godycki-Cwirko), Medical University of Lodz, Lodz, Poland.
authors: Maciek
authors: M
authors: Godycki-Cwirko
authors: Julius Center for Health Sciences and Primary Care (Teepe, Broekhuizen, Verheij), University Medical Center Utrecht, Utrecht, The Netherlands; Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute (VAXINFECTIO) (Loens, Lammens, Ieven, Goossens, Coenen), and Centre for General Practice, Primary and Interdisciplinary Care (Coenen), University of Antwerp, Antwerp, Belgium; Primary Care Medical Group (Little), University of Southampton Medical School, Southampton, UK; Nuffield Department of Primary Care Health Sciences (Butler), University of Oxford, Oxford, UK; Faculty of Health Sciences (Godycki-Cwirko), Medical University of Lodz, Lodz, Poland.
authors: Theo J M
authors: TJM
authors: Verheij