title: Procalcitonin guidance for reduction of antibiotic use in low-risk outpatients with community-acquired pneumonia.
abstract: OBJECTIVE
  Use of antibiotics in outpatients with community-acquired pneumonia (CAP) is empirical, which may lead to overuse and selection pressure for resistance. Procalcitonin (PCT) levels may predict the severity of CAP and may be used to guide antibiotic use in hospitalized patients. This study evaluated the value of PCT measurements for guiding antibiotic use in low-risk outpatients with CAP.
  
  
  METHODS
  This was a randomized intervention trial conducted between February 2005 and December 2008 that included 172 consecutive patients with suspected CAP, of whom 156 completed the study. The control group received antibiotics according to current guidelines. In the PCT group, antibiotic treatment was based on PCT levels as follows: <0.1 µg/L, strongly discouraged; ≤0.25 µg/L, discouraged; >0.25 µg/L, encouraged. The primary end-points were total antibiotic use and duration of antibiotic treatment; laboratory and clinical outcomes were measured.
  
  
  RESULTS
  Prescription of antibiotics on admission (84.4% vs 97.5%; P = 0.004), total antibiotic exposure (relative risk 0.55, 95% CI: 0.51-0.60; P = 0.003) and duration of antibiotic treatment (median 5 days vs 7 days; P < 0.001) were reduced in the PCT guidance group, compared with patients treated according to current guidelines. At 4-week follow up, all patients had survived and laboratory and clinical outcomes were similar in the two groups.
  
  
  CONCLUSIONS
  Under PCT guidance, antibiotic use was reduced and duration of antibiotic treatment was shortened in low-risk outpatients with CAP, without apparent harm.
authors.affiliation: Department of Emergency Medicine, Shanghai Fifth People's Hospital, Fudan University, Shanghai, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Long
authors.forename: Xingqi
authors.initials: X
authors.lastname: Deng
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.forename: Gang
authors.initials: G
authors.lastname: Lu
authors.forename: Juan
authors.initials: J
authors.lastname: Xie
authors.forename: Jianguo
authors.initials: J
authors.lastname: Tang
mesh_terms: D000328:Adult; D000553:Ambulatory Care; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D015415:Biomarkers / Q000097:blood; D002116:Calcitonin / Q000097:blood*; D015740:Calcitonin Gene-Related Peptide; D017714:Community-Acquired Infections / Q000097:blood / Q000188:drug therapy*; D023381:Endpoint Determination; D005260:Female; D006801:Humans; D057970:Inappropriate Prescribing; D008297:Male; D008875:Middle Aged; D011014:Pneumonia / Q000097:blood / Q000188:drug therapy*; D011237:Predictive Value of Tests; D011498:Protein Precursors / Q000097:blood*; D012307:Risk Factors; D012720:Severity of Illness Index; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D015415:Biomarkers; C000606589:CALCA protein, human; D011498:Protein Precursors; D002116:Calcitonin; D015740:Calcitonin Gene-Related Peptide