Internal and Emergency Medicine

, Volume 13, Issue 4, pp 539–547 | Cite as

Clinical mimics: an emergency medicine focused review of pneumonia mimics

  • Drew Alan Long
  • Brit Long
  • Alex Koyfman


Pneumonia is a common cause of morbidity and mortality in adults in the United States. While pneumonia classically presents with a fever, cough, and shortness of breath, the presentation can vary widely in adults. This review evaluates history and physical examination findings of pneumonia and several conditions that mimic pneumonia. Pneumonia is a potentially deadly disease. History and examination findings are variable in pneumonia, and many conditions mimic pneumonia. These conditions include pulmonary embolism, diffuse interstitial lung disease, endocarditis, vasculitis, diffuse alveolar hemorrhage, acute decompensated heart failure, tuberculosis, lung cancer, and acute respiratory distress syndrome. Emergency clinicians should assess the patient while resuscitation occurs. Early antibiotics and the diagnosis of pneumonia can improve outcomes. Key historical and physical examination findings may lead the clinician to consider other conditions that require immediate management. Using clinical evaluation and adjunctive imaging, these conditions can be diagnosed and treated. Knowledge of pneumonia mimics is vital for the care of patients with respiratory complaints. Pneumonia is common and may be deadly, and emergency clinicians must differentiate conditions that mimic pneumonia. Rapid evaluation and management may alleviate morbidity and mortality for each of these conditions. The history and physical examination, in addition to utilizing imaging modalities such as ultrasound and computed tomography, are vital in diagnosis of pneumonia mimics.


Pneumonia Mimic Endocarditis Vasculitis Interstitial Tuberculosis Lung cancer Acute respiratory distress syndrome 



This manuscript did not utilize any grants, and it has not been presented in abstract form. It does not reflect the views or opinions of the U.S. Government, U.S. Army, U.S. Air Force, Department of Defense, or SAUSHEC residency program.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Statement of human and animal rights

This article does not contain any studies with human participants or animals performed by any of the authors.

Informed consent



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© This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply 2018

Authors and Affiliations

  1. 1.Department of Emergency MedicineSan Antonio Military Medical CenterFort Sam HoustonUSA
  2. 2.Department of Emergency MedicineUniversity of Texas Southwestern Medical CenterDallasUSA

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