Patients with CAP should be treated for a minimum of 5 days (level I evidence*), should be afebrile for 48–72 h, and should have no more than 1 CAP-associated sign of clinical instability before discontinuation of therapy (level II evidence*). A longer duration of therapy may be needed if initial therapy was not active against the identified pathogen or if it was complicated by extrapulmonary infection, such as meningitis or endocarditis (level III evidence*).
The duration of treatment should generally not exceed 8 days in a responding patient [C2]. Biomarkers, particularly PCT, may guide shorter treatment duration.
C2: Insufficient evidence, from 1 RCT or >1 RCT, but no systematic review or meta-analysis
For community managed and for most patients admitted to hospital with low or moderate severity and uncomplicated pneumonia, 7 days of appropriate antibiotics is recommended. For those with high severity microbiologically undefined pneumonia, 7–10 days of treatment is proposed. This may need to be extended to 14 or 21 days according to clinical judgment, for example, where S. aureus or Gram-negative enteric bacilli pneumonia is suspected or confirmed. [C]
C: Formal combination of expert views
Level I evidence: evidence from well-conducted, randomized controlled trials; level II evidence: evidence from well-designed, controlled trials without randomization (including cohort, patient series, and case-control studies); level III evidence: evidence from case studies and expert opinion. ATS: American Thoracic Society; BTS: British Thoracic Society; CAP: community acquired pneumonia; ERS/ESCMID: European Respiratory Society and European Society for Clinical Microbiology and Infectious Diseases; IDSA: Infectious Diseases Society of America; PCT: procalcitonin; RCT: randomized controlled trial.
