Bacterial etiology of community-acquired pneumonia in immunocompetent hospitalized patients and appropriateness of empirical treatment recommendations: an international point-prevalence study

An accurate knowledge of the epidemiology of community-acquired pneumonia (CAP) is key for selecting appropriate antimicrobial treatments. Very few etiological studies assessed the appropriateness of empiric guideline recommendations at a multinational level. This study aims at the following: (i) describing the bacterial etiologic distribution of CAP and (ii) assessing the appropriateness of the empirical treatment recommendations by clinical practice guidelines (CPGs) for CAP in light of the bacterial pathogens diagnosed as causative agents of CAP. Secondary analysis of the GLIMP, a point-prevalence international study which enrolled adults hospitalized with CAP in 2015. The analysis was limited to immunocompetent patients tested for bacterial CAP agents within 24 h of admission. The CAP CPGs evaluated included the following: the 2007 and 2019 American Thoracic Society/Infectious Diseases Society of America (ATS/IDSA), the European Respiratory Society (ERS), and selected country-specific CPGs. Among 2564 patients enrolled, 35.3% had an identifiable pathogen. Streptococcus pneumoniae (8.2%) was the most frequently identified pathogen, followed by Pseudomonas aeruginosa (4.1%) and Klebsiella pneumoniae (3.4%). CPGs appropriately recommend covering more than 90% of all the potential pathogens causing CAP, with the exception of patients enrolled from Germany, Pakistan, and Croatia. The 2019 ATS/IDSA CPGs appropriately recommend covering 93.6% of the cases compared with 90.3% of the ERS CPGs (p < 0.01). S. pneumoniae remains the most common pathogen in patients hospitalized with CAP. Multinational CPG recommendations for patients with CAP seem to appropriately cover the most common pathogens and should be strongly encouraged for the management of CAP patients.