Legionellosis history and symptoms
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview
Overview
Legionellosis may manifest with either Legionnaires’ disease or Pontiac Fever. Legionnaires’ disease is more severe and typically manifests with fatigue, malaise, symptoms of pneumonia (fever, dyspnea, chest pain, and cough) and occasionally diarrhea and nausea. In contrast, Pontiac fever is a milder form of respiratory flu-like disease (fever and cough) but does not result in pneumonia. Patients with legionellosis often report a recent history of travel, hospitalization, exposure to contaminated water, or exposure to healthcare settings.
History
History
- Legionnaires’ disease typically manifests with pneumonia, which usually requires hospitalization and can be fatal in 10%–15% of cases.
- In contrast, clinical manifestations of Pontiac fever are milder than Legionnaires’ disease. Pontiac fever typically manifests with influenza-like illness (fever, headache, and myalgias) but no signs of pneumonia. Pontiac fever can affect healthy people, as well as those with underlying illnesses, and symptoms occur within 72 hours of exposure.
- Approximately 15%-20% of patients report a recent history of travel.
- Patients often report recent hospitalizations and exposure to healthcare settings.[1][2]
Symptoms
Symptoms
Legionnaires’ Disease
Symptoms of Legionnaires’ disease may include:[1][2]
- Fever
- Chest pain
- Dyspnea
- Hemoptysis
- Non-productive cough
- Gastrointestinal symptoms, such as diarrhea, nausea, vomiting, and abdominal pain
- Headache
- Myalgia
- Arthralgia
- Ataxia
- Altered mental status
Pontiac Fever
There are no lower respiratory manifestations with Pontiac fever. Symptoms of Pontiac fever may include:
References
References
- ↑ 1.0 1.1 Top 10 Things Every Clinician Needs to Know About Legionellosis. Centers for Disease Control and Prevention. Accessed on August 5, 2015. http://www.cdc.gov/legionella/clinicians.html
- ↑ 2.0 2.1 Phin N, Parry-Ford F, Harrison T, Stagg HR, Zhang N, Kumar K; et al. (2014). “Epidemiology and clinical management of Legionnaires’ disease”. Lancet Infect Dis. 14 (10): 1011–21. doi:10.1016/S1473-3099(14)70713-3. PMID 24970283.
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