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Fatal Legionella pneumophila serogroup 1 pleural empyema: A case report
François Maillet1, Nicolas Bonnet1, Typhaine Billard-Pomares2
1Intensive Care Unit, Avicenne Hospital, Assistance Publique - Hôpitaux de Paris, Bobigny 93000, France.
Background:
Legionella pneumophila (L. pneumophila) is a gram-negative intracellular bacillus composed of sixteen different serogroups. It is mostly known to cause pneumonia in individuals with known risk factors as immunocompromised status, tobacco use, chronic organ failure or age older than 50 years. Although parapneumonic pleural effusion is frequent in legionellosis, pleural empyema is very uncommon. In this study, we report a case of fatal pleural empyema caused by L. pneumophila serogroup 1 in an 81-year-old man with multiple risk factors.
Case Summary:
An 81-year-old man presented to the emergency with a 3 wk dyspnea, fever and left chest pain. His previous medical conditions were chronic lymphocytic leukemia, diabetes mellitus, chronic kidney failure, hypertension and hyperlipidemia, without tobacco use. Chest X-ray and comouted tomography-scan confirmed a large left pleural effusion, which puncture showed a citrine exudate with negative standard bacterial cultures. Despite intravenous cefotaxime antibiotherapy, patient's worsening condition after 10 d led to thoracocentesis and evacuation of 2 liters of pus. The patient progressively developed severe hypoxemia and multiorgan failure occurred. The patient was treated by antibiotherapy with cefepime and amikacin and with adequate symptomatic shock treatment, but died of uncontrolled sepsis. The next day, cultures of the surgical pleural liquid samples yielded L. pneumophila serogroup 1, consistent with the diagnosis of pleural legionellosis.
Conclusion:
L. pneumophila should be considered in patients with multiple risk factors and undiagnosed pleural empyema unresponsive to conventional antibiotherapy.
Insights
Legionella pneumophila (L. pneumophila) can cause rare but fatal pleural empyema in elderly patients with multiple risk factors. Early consideration of L. pneumophila is crucial for undiagnosed empyema unresponsive to standard treatment.
Area of Science:
- Medical Microbiology
- Infectious Diseases
- Pulmonology
Background:
- Legionella pneumophila (L. pneumophila) is a gram-negative bacterium
- Typically causes pneumonia, especially in immunocompromised individuals
- Pleural empyema is an uncommon complication of legionellosis
Observation:
- An 81-year-old male with multiple comorbidities presented with dyspnea and chest pain
- Initial evaluation revealed a large pleural effusion with negative standard bacterial cultures
- Despite broad-spectrum antibiotics, the patient's condition deteriorated, leading to severe hypoxemia and multiorgan failure
Findings:
- Pleural fluid cultures eventually identified L. pneumophila serogroup 1
- The patient died from uncontrolled sepsis secondary to L. pneumophila pleural empyema
- This case highlights a rare but fatal presentation of L. pneumophila infection
Implications:
- L. pneumophila should be considered in the differential diagnosis of undiagnosed pleural empyema
- Patients with multiple risk factors and empyema unresponsive to conventional therapy warrant specific Legionella testing
- This case underscores the importance of considering atypical pathogens in severe infections.
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