Pseudomonas aeruginosa in Chronic Obstructive Pulmonary Disease Patients with Frequent Hospitalized Exacerbations: A Prospective Multicentre Study

Abstract

Background: Pseudomonas aeruginosa (PA) is a common microorganism related to severe exacerbations in Chronic Obstructive Pulmonary Disease (COPD). However, their role in COPD patients with frequent hospitalized exacerbations (FHE) is not well described.

Objectives: We aimed to determine prevalence, risk factors, susceptibility patterns and impact on outcomes of PA in COPD patients with FHE.

Methods: Prospective observational multicentre study that included COPD patients with FHE. The cohort was stratified in 2 groups according to the presence or absence of PA isolation in sputum. Patients were followed up for 12 months.

Results: We enrolled 207 COPD patients with FHE. In 119 patients (57%), a valid sputum culture was collected. Of them, PA was isolated in 21 patients (18%). The risk factors associated with PA were prior use of systemic corticosteroids (OR 3.3, 95% CI 1.2-9.7, p = 0.01) and prior isolation of PA (OR 4.36, 95% CI 1.4-13.4, p < 0.01). Patients with PA had an increased risk of having ≥3 readmissions (OR 4.1, 95% CI 1.3-12.8, p = 0.01) and higher PA isolation rate (OR 7.7, 95% CI 2.4-24.6, p < 0.001) during the follow-up period. In 14 patients (67%), PA was resistant to at least one antibiotic tested. PA persisted in the sputum in 70% of patients.

Conclusions: The presence of PA was related to 3 or more readmissions during the 1-year follow-up and PA persisted in the sputum despite an appropriate antibiotic treatment. This finding suggested an important role of PA in the course of the disease of COPD patients with FHE.

Keywords: Chronic obstructive pulmonary disease; Exacerbation; Pseudomonas aeruginosa; Readmission; Risk factors.