Burden and risk factors for<i>Pseudomonas aeruginosa</i>community-acquired pneumonia: a multinational point prevalence study of hospitalised patients

<i>Pseudomonas aeruginosa</i> is a challenging bacterium to treat due to its intrinsic resistance to the antibiotics used most frequently in patients with community-acquired pneumonia (CAP). Data about the global burden and risk factors associated with <i>P. aeruginosa</i>-CAP are limited. We assessed the multinational burden and specific risk factors associated with <i>P. aeruginosa-</i>CAP.We enrolled 3193 patients in 54 countries with confirmed diagnosis of CAP who underwent microbiological testing at admission. Prevalence was calculated according to the identification of <i>P. aeruginosa</i> Logistic regression analysis was used to identify risk factors for antibiotic-susceptible and antibiotic-resistant <i>P. aeruginosa-</i>CAP.The prevalence of <i>P. aeruginosa</i> and antibiotic-resistant <i>P. aeruginosa-</i>CAP was 4.2% and 2.0%, respectively. The rate of <i>P. aeruginosa</i> CAP in patients with prior infection/colonisation due to <i>P. aeruginosa</i> and at least one of the three independently associated chronic lung diseases (<i>i.e.</i> tracheostomy, bronchiectasis and/or very severe chronic obstructive pulmonary disease) was 67%. In contrast, the rate of <i>P. aeruginosa-</i>CAP was 2% in patients without prior <i>P. aeruginosa</i> infection/colonisation and none of the selected chronic lung diseases.The multinational prevalence of <i>P. aeruginosa-</i>CAP is low. The risk factors identified in this study may guide healthcare professionals in deciding empirical antibiotic coverage for CAP patients.