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Published on: May 4, 2018
Community-Acquired Pneumonia Due to Multidrug- and Non-Multidrug-Resistant Pseudomonas aeruginosa
Catia Cillóniz1, Albert Gabarrús1, Miquel Ferrer1
1Department of Pneumology, Institut Clinic del Tórax, Hospital Clinic of Barcelona - Institut d'Investigacions Biomèdiques August Pi i Sunyer, University of Barcelona - SGR 911- Ciber de Enfermedades Respiratorias (Ciberes) Barcelona, Spain.
Background:
Pseudomonas aeruginosa is not a frequent pathogen in community-acquired pneumonia (CAP). However, in patients with severe CAP, P aeruginosa can be the etiology in 1.8% to 8.3% of patients, with a case-fatality rate of 50% to 100%. We describe the prevalence, clinical characteristics, outcomes, and risk factors associated with CAP resulting from multidrug-resistant (MDR) and non-MDR P aeruginosa.
Methods:
Prospective observational study of 2,023 consecutive adult patients with CAP with definitive etiology.
Results:
P aeruginosa was found in 77 (4%) of the 2,023 cases with microbial etiology. In 22 (32%) of the 68 cases of P aeruginosa with antibiogram data, the isolates were MDR. Inappropriate therapy was present in 49 (64%) cases of P aeruginosa CAP, including 17/22 (77%) cases of MDR P aeruginosa CAP. Male sex, chronic respiratory disease, C-reactive protein <12.35 mg/dL, and pneumonia severity index risk class IV to V were independently associated with P aeruginosa CAP. Prior antibiotic treatment was more frequent in MDR P aeruginosa CAP compared with non-MDR P aeruginosa (58% vs 29%, P = .029), and was the only risk factor associated with CAP resulting from MDR P aeruginosa. In the multivariate analysis, age ≥65 years, CAP resulting from P aeruginosa, chronic liver disease, neurologic disease, nursing home, criteria of ARDS, acute renal failure, ICU admission, and inappropriate empiric treatment were the factors associated with 30-day mortality.
Conclusions:
P aeruginosa is an individual risk factor associated with mortality in CAP. The risk factors described can help clinicians to suspect P aeruginosa and MDR P aeruginosa.
Insights
Pseudomonas aeruginosa is a significant cause of severe community-acquired pneumonia (CAP), associated with high mortality. Identifying risk factors for P aeruginosa and multidrug-resistant (MDR) P aeruginosa CAP is crucial for effective treatment.
Area of Science:
- Infectious Diseases
- Pulmonology
- Microbiology
Background:
- Pseudomonas aeruginosa is an uncommon cause of community-acquired pneumonia (CAP).
- In severe CAP cases, P aeruginosa accounts for 1.8%-8.3% of etiologies with a 50%-100% fatality rate.
- This study investigates P aeruginosa in CAP, focusing on multidrug-resistant (MDR) strains.
Purpose of the Study:
- To determine the prevalence, clinical features, and outcomes of P aeruginosa in CAP.
- To identify risk factors for P aeruginosa and MDR P aeruginosa infections in CAP patients.
Main Methods:
- A prospective observational study involved 2,023 adult patients with CAP.
- Etiological diagnosis was confirmed for all cases.
- Antibiogram data was analyzed for P aeruginosa isolates.
Main Results:
- P aeruginosa was identified in 4% of CAP cases (77/2023).
- MDR P aeruginosa accounted for 32% (22/68) of P aeruginosa isolates.
- Inappropriate therapy was common (64%), especially with MDR strains (77%).
- Risk factors for P aeruginosa CAP included male sex, chronic respiratory disease, low C-reactive protein, and high pneumonia severity index.
- Prior antibiotic use was linked to MDR P aeruginosa CAP.
- Factors associated with 30-day mortality included older age, P aeruginosa CAP, chronic liver disease, neurologic disease, nursing home residency, ARDS, acute renal failure, ICU admission, and inappropriate empiric treatment.
Conclusions:
- P aeruginosa is an independent risk factor for mortality in CAP.
- Recognizing specific risk factors can aid clinicians in suspecting P aeruginosa and MDR P aeruginosa infections.
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