Summary
Definition
History and exam
Key diagnostic factors
- persistent cough
- dry cough
- prolonged symptoms
- fever
- adventitious sounds on physical exam
Other diagnostic factors
- throat involvement
- rash
- headache
- hepatitis
Risk factors
- close community settings
- exposure to a person with respiratory tract infection
- cigarette smoking
- age <30 years
- immunosuppression
- asplenia
Diagnostic tests
1st tests to order
- CBC
- hemoglobin
- LFTs
- pulse oximetry
- BUN and electrolytes
- C-reactive protein
- chest x-ray
Tests to consider
- nucleic acid amplification test (NAAT)
- serology
- culture ± Gram stain
- antigen test
Emerging tests
- point of care ultrasound, lung
Treatment algorithm
with pneumonia
Contributors
Authors
Lorenzo Dr Francesco, MD, SFHM, FACP
Professor of Medicine
Department of Medicine
Division of General Internal Medicine
Emory University School of Medicine
Atlanta, GA
Disclosures
LDF declares that he has no competing interests.
Takeshi Saraya, MD, PhD
Professor
Department of Respiratory Medicine
Kyorin University School of Medicine
Tokyo
Japan
Disclosures
TS declares that he has no competing interests.
Acknowledgements
Dr Di Francesco and Dr Takeshi Saraya would like to gratefully acknowledge Dr Ran Nir-Paz, a previous contributor to this topic. RNP declares no competing interests.
Peer reviewers
Enno Jacobs, MD
Director
Institute for Medical Microbiology and Hygiene
Dresden
Germany
Disclosures
EJ declares that he has no competing interests.
Laura J. Christie, MD
Research Scientist
Pediatric Infectious Disease
California Department of Public Health
Viral and Rickettsial Disease Laboratory
Richmond
CA
Disclosures
LC declares that she has no competing interests.
Peer reviewer acknowledgements
BMJ Best Practice topics are updated on a rolling basis in line with developments in evidence and guidance. The peer reviewers listed here have reviewed the content at least once during the history of the topic.
Disclosures
Peer reviewer affiliations and disclosures pertain to the time of the review.
References
Key articles
British Thoracic Society. BTS guidelines for the management of community acquired pneumonia in adults: update 2009. Jan 2015 [internet publication].Full text
Metlay JP, Waterer GW, Long AC, et al. Diagnosis and treatment of adults with community-acquired pneumonia. An official clinical practice guideline of the American Thoracic Society and Infectious Diseases Society of America. Am J Respir Crit Care Med. 2019 Oct 1;200(7):e45-67.Full text Abstract
Reference articles
A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.

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