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Evidencia revisada por última vez: 12 Feb 2026
Tema actualizado por última vez: 24 Jan 2025

Resumen

Definition

History and exam

Key diagnostic factors

  • cough with increasing sputum production
  • fever or chills
  • dyspnea
  • pleuritic pain
  • abnormal auscultatory findings

Other diagnostic factors

  • dullness to percussion
  • myalgia
  • arthralgia
  • confusion

Risk factors

  • age >65 years
  • residence in a healthcare setting
  • COPD
  • exposure to cigarette smoke
  • alcohol abuse
  • poor oral hygiene
  • use of acid-reducing drugs, inhaled corticosteroids, antipsychotics, antidiabetic drugs
  • contact with children
  • HIV infection
  • diabetes mellitus
  • chronic renal disease
  • chronic liver disease
  • use of opioids

Diagnostic investigations

1st investigations to order

  • chest x-ray
  • CBC
  • serum electrolytes/blood urea nitrogen
  • liver function tests
  • blood glucose
  • arterial blood gases/oximetry
  • blood culture
  • sputum culture

Investigations to consider

  • point-of-care lung ultrasound
  • CT chest
  • urinary antigen testing for Legionella and pneumococcus
  • serum C-reactive protein
  • serum procalcitonin
  • thoracocentesis and pleural fluid culture
  • bronchoscopy
  • tests for respiratory viruses
  • molecular microbiological techniques

Treatment algorithm

Contributors

Expert advisers

Catia Cilloniz, MD, PhD, FERS

Applied Research in Respiratory Diseases

Hospital Clinic of Barcelona

CIBERES

IDIBAPS

Associate Professor

University of Barcelona

Barcelona

Spain

Disclosures

CC is an author of a number of references cited in this topic.

Antoni Torres, MD, PhD

Professor of Medicine

Director

Pulmonary Intensive Care Unit

Respiratory Institute

Hospital Clinic of Barcelona

Barcelona

Spain

Disclosures

AT is an author of a number of references cited in this topic.

Peer reviewers

Barbara Jones, MD, MSc

Assistant Professor

Division of Pulmonary and Critical Care Medicine

University of Utah

Salt Lake City

UT

Disclosures

BJ declares that she has no competing interests.

Denise Nassisi, MD

Associate Professor

Departments of Emergency Medicine and Medicine

Icahn School of Medicine at Mount Sinai

New York

NY

Disclosures

DN declares that she has no competing interests.

Jeremy Brown, MBBS, FRCP, PhD

Professor of Respiratory Infection/Honorary Consultant

University College London

London

UK

Disclosures

JB was a member of the NICE pneumonia guidelines committee.

Grant Waterer, MBBS, PhD, MBA, FRACP, FCCP

Professor of Medicine

Royal Perth Hospital

Perth

Australia

Disclosures

GW declares that he has no competing interests.

Nathan Dean, MD

Professor (clinical) of Medicine

Section Chief Pulmonary Critical Care Medicine

University of Utah

Intermountain Medical Center

Murray

UT

Divulgaciones

ND declares that he has no competing interests.

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Artículos principales

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.Texto completo  Resumen

Artículos de referencia

Una lista completa de las fuentes a las que se hace referencia en este tema está disponible aquí.

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