title: Sputum colour for diagnosis of a bacterial infection in patients with acute cough.
abstract: OBJECTIVE
  Sputum colour plays an important role in the disease concepts for acute cough, both in the patients' and the doctors' view. However, it is unclear whether the sputum colour can be used for diagnosis of a bacterial infection.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  A total of 42 GP practices in Dusseldorf, Germany.
  
  
  METHODS
  Sputum samples obtained from 241 patients suffering from an episode of acute cough seeing their doctor within a routine consultation.
  
  
  METHODS
  Relation of sputum colour and microbiological proof of bacterial infection defined as positive culture and at least a moderate number of leucocytes per low magnification field.
  
  
  RESULTS
  In 28 samples (12%) a bacterial infection was proven. Yellowish or greenish colour of the sputum sample and bacterial infection showed a significant correlation (p = 0.014, Fisher's exact test). The sensitivity of yellowish or greenish sputum used as a test for a bacterial infection was 0.79 (95% CI 0.63-0.94); the specificity was 0.46 (95% CI 0.038-0.53). The positive likelihood-ratio (+LR) was 1.46 (95% CI 1.17-1.85).
  
  
  CONCLUSIONS
  The sputum colour of patients with acute cough and no underlying chronic lung disease does not imply therapeutic consequences such as prescription of antibiotics.
authors.affiliation: Department of General Practice, University Hospital, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany. altiner@med.uni-duesseldorf.de
authors.forename: Attila
authors.initials: A
authors.lastname: Altiner
authors.forename: Stefan
authors.initials: S
authors.lastname: Wilm
authors.forename: Walter
authors.initials: W
authors.lastname: Däubener
authors.forename: Christiane
authors.initials: C
authors.lastname: Bormann
authors.forename: Michael
authors.initials: M
authors.lastname: Pentzek
authors.forename: Heinz-Harald
authors.initials: HH
authors.lastname: Abholz
authors.forename: Martin
authors.initials: M
authors.lastname: Scherer
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001424:Bacterial Infections / Q000188:drug therapy / Q000382:microbiology*; D003116:Color; D003371:Cough / Q000188:drug therapy / Q000382:microbiology*; D003430:Cross-Sectional Studies; D003657:Decision Making; D011307:Drug Prescriptions; D006801:Humans; D012141:Respiratory Tract Infections / Q000188:drug therapy / Q000382:microbiology*; D012680:Sensitivity and Specificity; D013183:Sputum / Q000382:microbiology*; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents