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Legionella infection

Last reviewed: 12 Sep 2025
Last updated: 10 May 2024

Summary

Definition

History and exam

Key diagnostic factors

  • known acquaintance with Legionella
  • fever
  • headache
  • crackles/rhonchi
Full details

Other diagnostic factors

  • productive cough
  • dyspnea
  • nausea/vomiting
  • abdominal pain
  • hypoxia
  • tachycardia
Full details

Risk factors

  • non-municipal water supply
  • recent residential plumbing repair
  • smoking
  • cytotoxic chemotherapy
  • lung transplant recipient
  • corticosteroids
  • electric water heater
  • working >40 hours per week
  • recent travel
  • diabetes mellitus
  • professional driver
  • use of whirlpool spas
  • living close to a cooling tower
  • filling nebulizer, humidifiers, ventilator tubing, or lavage equipment with tap water
  • close proximity to a decorative fountain
  • consumption of Legionella pneumophila-contaminated ice
  • delivery by water birth
  • exposure to contaminated compost
  • exposure to rainwater
Full details

Diagnostic tests

1st tests to order

  • CBC
  • complete metabolic profile
  • chest x-ray
  • CT abdomen
  • urine antigen detection of Legionella pneumophila serogroup 1
  • sputum Gram stain
  • cultures
Full details

Tests to consider

  • Legionella pneumophila polymerase chain reaction (PCR)
  • Legionella pneumophila serology
Full details

Treatment algorithm

ACUTE

mild/moderate Legionella pneumonia

severe Legionella pneumonia or no response to initial therapy

Contributors

Authors

Forest W. Arnold, DO, MSc, FIDSA
Forest W. Arnold

Professor of Medicine

Division of Infectious Diseases

Department of Medicine

School of Medicine

University of Louisville

Louisville

KY

გაფრთხილება:

FWA has received grants from the National Institutes of Health, Health Resources and Services Administration, as well as Pfizer, Covarsa, Merck, and Gilead pharmaceutical companies.

მადლიერება

Dr Forest W. Arnold would like to gratefully acknowledge Dr Allen Griffin, a previous contributor to this topic.

გაფრთხილება:

AG declares that he has no competing interests.

რეცენზენტები

Victor L. Yu, MD

Professor of Medicine

University of Pittsburgh

Pittsburgh

PA

გაფრთხილება:

VLY declares that he 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.

წყაროები

ჩვენი მტკიცებულებებისა და სარედაქციო ჯგუფები თანამშრომლობენ საერთაშორისო ექსპერტებსა და რეცენზენტებთან, რათა უზრუნველვყოთ თქვენი წვდომა კლინიკურად ყველაზე მნიშვნელოვან ინფორმაციაზე.

ძირითადი სტატიები

Phin N, Parry-Ford F, Harrison T, et al. Epidemiology and clinical management of Legionnaires' disease. Lancet Infect Dis. 2014 Oct;14(10):1011-21.სრული ტექსტი  აბსტრაქტი

Centers for Disease Control and Prevention. CDC Yellow Book 2024: health information for international travel. Section 5: travel-associated infections & diseases (bacterial) - legionnaires' disease & pontiac fever. May 2023 [internet publication].სრული ტექსტი

US Centers for Disease Control and Prevention. Legionella (Legionnaires' disease and pontiac fever): diagnosis, treatment, & prevention. March 2021 [internet publication].სრული ტექსტი

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.სრული ტექსტი  აბსტრაქტი

გამოყენებული სტატიები

ამ თემაში მოხსენიებული წყაროების სრული სია ხელმისაწვდომია მომხმარებლებისთვის, რომლებსაც აქვთ წვდომა BMJ Best Practice-ის ყველა ნაწილზე.
  • Legionella infection images
  • დიფერენციული დიაგნოზები

    • Coronavirus disease 2019 (COVID-19)
    • Bacterial pneumonia
    • Hospital-acquired pneumonia
    მეტი დიფერენციული დიაგნოზები
  • გაიდლაინები

    • Pneumonia in adults: diagnosis and management
    • Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults
    მეტი გაიდლაინები
  • კალკულატორები

    Community-acquired pneumonia severity index (PSI) for adults

    CURB-65 pneumonia severity score

    მეტი კალკულატორები
  • padlock-lockedშედით სისტემაში ან გამოიწერეთ BMJ Best Practice

ამ მასალის გამოყენება ექვემდებარება ჩვენს განცხადებას