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Last reviewed: 8 Jan 2026
Last updated: 31 Jan 2023

Summary

Definition

History and exam

Key diagnostic factors

  • tos con aumento de la producción de esputo
  • disnea
  • dolor torácico pleurítico
  • rigores o sudores nocturnos
  • fiebre
  • hallazgos en la auscultación anormales
  • confusión
  • presencia de factores de riesgo
Full details

Other diagnostic factors

  • mialgia
  • malestar general
  • anorexia
  • letargo
  • empeoramiento de las condiciones preexistentes
  • dolor de garganta
  • cefalea
  • náuseas
  • dolor abdominal
  • diarrea
Full details

Risk factors

  • edad >65 años
  • residencia en un contexto de asistencia sanitaria
  • Enfermedad pulmonar obstructiva crónica (EPOC)
  • exposición al humo de cigarrillo
  • abuso de alcohol
  • higiene bucal deficiente
  • fármacos que reducen el ácido
  • contacto con niños
  • diabetes mellitus
  • nefropatía crónica
  • hepatopatía crónica.
  • uso de opiáceos
Full details

Diagnostic tests

1st tests to order

  • radiografía de tórax
  • oximetría de pulso
  • gasometría arterial (GSA)
  • urea y electrolitos
  • hemograma completo
  • proteína C reactiva (PCR)
  • pruebas de función hepática
Full details

Tests to consider

  • hemocultivo
  • cultivo de esputo (tinción de Gram ±)
  • prueba de antígenos en orina para Legionella y neumococo
  • reacción en cadena de la polimerasa (PCR) y/o pruebas serológicas
  • exploración de tórax por TC
  • ecografía de tórax
  • toracocentesis y cultivo del líquido pleural
  • angiografía pulmonar por tomografía computarizada (APTC)
  • broncoscopia
  • procalcitonina sérica
  • PCR en el punto de atención
Full details

Treatment algorithm

INITIAL

sospecha de NAC: presentarse en el hospital con una enfermedad potencialmente mortal

sospecha de NAC: presentarse en el hospital sin enfermedad potencialmente mortal

sospecha de NAC: presentación en el entorno comunitario

ACUTE

NAC confirmada en la radiografía de tórax: presentación en el hospital

NAC confirmada en la radiografía de tórax: presentación en el entorno comunitario

Contributors

Expert advisers

Jonathan Bennett, MD

Honorary Professor of Respiratory Sciences

University of Leicester

Respiratory Consultant

Glenfield Hospital

Leicester

UK

Biography

JB is deputy medical director RCP Invited service Reviews, and speaker at National Society (e.g., BTS), Primary Care respiratory Society, and Society Cardiothoracic Surgeons meetings.

Disclosures

JB declares that he has no competing interests.

Acknowledgements

BMJ Best Practice would like to gratefully acknowledge the previous team of expert contributors, whose work has been retained in parts of the content:

Catia Cilloniz MSc, PhD

Post-doctoral Research

Pneumology Department

Hospital Clinic of Barcelona

CIBERES

IDIBAPS

Barcelona

Spain

Antoni Torres MD, PhD

Professor of Medicine

Director

Pulmonary Intensive Care Unit

Respiratory Institute

Hospital Clinic of Barcelona

Barcelona

Spain

Disclosures

CC and AT are each authors of a number of references cited in this topic.

Peer reviewers

Wei Shen Lim

Consultant Respiratory Physician and Honorary Professor of Medicine

Nottingham University Hospitals NHS Trust

Nottingham

UK

Disclosures

WSL was chairman of the British Thoracic Society community-acquired pneumonia guidelines committee and a member of the guideline development group for the National Institute for Health and Care Excellence pneumonia guidelines. His institution has received unrestricted investigator-initiated research funding from Pfizer for a multicentre study of pneumococcal pneumonia in which he was the chief investigator, and research funding from the National Institute for Health Research for studies in pneumonia in which he was the principal investigator. He is also an author of at least one reference cited in the topic.

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

Our in-house evidence and editorial teams collaborate with international expert contributors and peer reviewers to ensure that we provide access to the most clinically relevant information possible.

Key articles

Lim WS, Baudouin SV, George RC, et al; Pneumonia Guidelines Committee of the BTS Standards of Care Committee. British Thoracic Society guidelines for the management of community acquired pneumonia in adults: update 2009. Thorax. 2009 Oct;64(suppl 3):iii1-55.Full text  Abstract

National Institute for Health and Care Excellence. Pneumonia in adults: diagnosis and management. July 2022 [internet publication].Full text

British Thoracic Society. 2015 - Annotated BTS guideline for the management of CAP in adults (2009) summary of recommendations. Jan 2015 [internet publication].Full text

O'Driscoll BR, Howard LS, Earis J, et al. BTS guideline for oxygen use in adults in healthcare and emergency settings. Thorax. 2017 Jun;72 (Suppl 1):ii1-90.Full text  Abstract

National Institute for Health and Care Excellence. Pneumonia (community-acquired): antimicrobial prescribing. Sep 2019 [internet publication].Full text

Reference articles

A full list of sources referenced in this topic is available here.

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