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

Pseudomonas aeruginosa is a challenging bacterium to treat due to its intrinsic antibiotic resistance to the most frequently used antibiotics in patients with community-acquired pneumonia (CAP). Data about the global burden and risk factors associated with P. aeruginosa-CAP are limited. We assessed the multinational burden and specific risk factors associated with P. aeruginosa-CAP.

We enrolled 3,193 patients in 54 countries with confirmed diagnosis of CAP that underwent microbiological testing at admission. Prevalence was calculated according to the identification of P. aeruginosa. Logistic regression analysis was used to identify risk factors for antibiotic-susceptible and antibiotic-resistant P. aeruginosa-CAP.

The prevalence of P. aeruginosa and antibiotic-resistant P. aeruginosa-CAP was 4.2% and 2.0%, respectively. The rate of P. aeruginosa CAP in patients with prior infection/colonisation due to P. aeruginosa and at least one of the three independently associated chronic lung diseases [i.e., tracheostomy, bronchiectasis and/or very severe COPD]) was 67%. In contrast, the rate of P. aeruginosa CAP was 2% in patients without prior P. aeruginosa infection/colonisation and none of the selected chronic lung diseases.

The multinational prevalence of P. aeruginosa-CAP is low. The risk factors identified in this study may guide healthcare professionals in deciding empirical antibiotic coverage for CAP patients.