Risk Factors for Presence of Resistant Microorganisms in Sputum Cultures of Patients with Infectious Exacerbations of Chronic Obstructive Lung Disease

Introduction: Antibiotics reduce the risk of short-term mortality. Certain bacteria may be resistant to initial regimens which is related to mortality. The aim of this study was to find risk factors for the presence of resistant bacteria during exacerbation of Chronic Obstructive Pulmonary Disease (COPD). Materials and Methods: Ethics committee approval was obtained for the study. The patients hospitalized with an exacerbation of COPD between 2015 and 2020 were retrospectively ieviewed. The patients with a sputum culture result were divided into: Group A with conventional microorganisms (susceptible to initial antibiotic regimen) and Group B with non-conventional microorganisms (resistant to initial antibiotic regimen). The risk factors for Group B microorganisms were investigated. Results: One hundred and nineteen patients were included in the study. Median age was 68 (40-88) years. There were 22 patients in Group A and 97 in Group B. Most common microorganism in Group A was Haemophilus influenza (12.6%). Most encountered microorganisms in Group B were Pseudomonas aeruginosa (49.6%). Male sex (HR= 2.9; 95% CI= 0.9-9.5; p= 0.073), age >61 (HR=4.8; 95% CI= 1.7-13.6; p= 0.003), and >5 hospitalizations last year (HR= 8.2; 95% CI= 0.9-67.7; p= 0.051) were found to be independent risk factors for resistant microorganisms. Conclusion: Proposed risk factors for the isolation of multidrug resistant microorganism in patients hospitalized with COPD exacerbations should be considered when choosing the initial antibiotic regimen.