Feature Article

Community-acquired pneumonia in adults

Patrick GP Charles, Paul DR Johnson



The recommended empirical therapy in adults for the common condition community acquired pneumonia is combination therapy with a narrow spectrum beta lactam antibiotic, to treat typical pathogens, and a macrolide antibiotic or doxycycline, to treat atypical pathogens.

Key Points

  • Community-acquired pneumonia (CAP) is defined as pneumonia occurring in an immunocompetent patient who has not been in hospital for at least 14 days.
  • CAP can be difficult to differentiate clinically from many other illnesses, the most common being viral respiratory tract infections. Chest x-ray infiltrate is the feature that best identifies patients as having pneumonia.
  • Patients with normal chest x-rays are unlikely to benefit from taking antibiotics.
  • Features of CAP that suggest the need for hospitalisation are severe breathlessness, confusion, inability to maintain oral intake, hypotension, hypoxia and multilobar or bilateral changes on chest x-ray.
  • Treatment recommendations for CAP are controversial but existing Australian guidelines to use combination antibiotic therapy aimed at typical and atypical pathogens are appropriate.