Legionnaires Disease Differential Diagnoses

Updated: Mar 11, 2021
  • Author: Chinelo N Animalu, MD, MPH, FIDSA; Chief Editor: Michael Stuart Bronze, MD  more...
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Diagnostic Considerations

Patients diagnosed with Legionella pneumonia are not usually coinfected with other organisms (eg, pneumococcal species). The differential diagnoses include other atypical pathogens (eg, Mycoplasma, psittacosis), Chlamydophila pneumoniae, tularemia, and Coxiella burnetii.L pneumophila bacterium represents a definite pathogen; therefore, its isolation always indicates infection.

Differentials in Legionnaires disease (LD) also include the following:

  • Aspiration pneumonia

  • Bacterial pneumonia

  • Viral pneumonia

  • Prostatitis

  • Respiratory distress syndrome

  • Septic shock

  • Typical community-acquired pneumonias (CAPs)

  • Atypical CAPs

  • Severe CAP