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[Increasing incidence of community-acquired pneumonia caused by atypical microorganisms]
M A Tazón-Varela1, H Alonso-Valle2, P Muñoz-Cacho3
1Servicio de Urgencias, Hospital de Laredo, Laredo, Cantabria, España.
Introduction:
Knowing the most common microorganisms in our environment can help us to make proper empirical treatment decisions. The aim is to identify those microorganisms causing community-acquired pneumonia.
Patients And Methods:
An observational, descriptive and prospective study was conducted, including patients over 14 years with a clinical and radiographic diagnosis of community-acquired pneumonia during a 383 consecutive day period. A record was made of sociodemographic variables, personal history, prognostic severity scales, progress, and pathogenic agents. The aetiological diagnosis was made using blood cultures, detection of Streptococcus pneumoniae and Legionella pneumophila urinary antigens, sputum culture, influenza virus and Streptococcus pyogenes detection. Categorical variables are presented as absolute values and percentages, and continuous variables as their means and standard deviations.
Results:
Of the 287 patients included in the study (42% women, mean age 66±22 years), 10.45% died and 70% required hospital admission. An aetiological diagnosis was achieved in 43 patients (14.98%), with 16 microorganisms found in 59 positive samples. The most frequently isolated pathogen was Streptococcus pneumonia (24/59, 41%), followed by gram-negative enteric bacilli, Klebsiella pneumonia, Escherichia coli, Serratia marcescens and Enterobacter cloacae isolated in 20% of the samples (12/59), influenza virus (5/59, 9%), methicillin-resistant Staphylococcus aureus (3/59, 5%), Pseudomonas aeruginosa (2/59, 3%), Moraxella catarrhalis (2/59, 3%), Legionella pneumophila (2/59, 3%), and Haemophilus influenza (2/59, 3%). Polymicrobial infections accounted for 14% (8/59).
Conclusion:
A high percentage of atypical microorganisms causing community-acquired pneumonia were found.
Insights
This study identified common microorganisms causing community-acquired pneumonia (CAP). Streptococcus pneumoniae was the most frequent pathogen, highlighting its importance in empirical CAP treatment strategies.
Area of Science:
- Infectious Diseases
- Microbiology
- Clinical Medicine
Background:
- Identifying common pathogens is crucial for effective empirical treatment of community-acquired pneumonia (CAP).
- Understanding the microbial landscape of CAP aids in optimizing clinical decision-making and patient outcomes.
Purpose of the Study:
- To identify the microorganisms responsible for community-acquired pneumonia (CAP).
- To inform empirical treatment strategies by characterizing prevalent CAP pathogens.
Main Methods:
- An observational, descriptive, prospective study included 287 patients diagnosed with CAP.
- Etiological diagnosis involved blood cultures, urinary antigen detection (Streptococcus pneumoniae, Legionella pneumophila), sputum culture, and viral detection.
- Sociodemographic data, patient history, and severity scales were recorded.
Main Results:
- Streptococcus pneumoniae was the most common pathogen (41%).
- Gram-negative enteric bacilli (Klebsiella pneumoniae, Escherichia coli, etc.) accounted for 20% of isolates.
- Influenza virus, MRSA, Pseudomonas aeruginosa, and Legionella pneumophila were also identified; 14% of infections were polymicrobial.
Conclusions:
- A significant proportion of community-acquired pneumonia cases were attributed to atypical microorganisms.
- Findings underscore the diverse etiological agents involved in CAP, necessitating broad-spectrum empirical therapy.
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