Prevalence of Extended-Spectrum Beta-lactamase Producing Microorganisms and Respiratory Infections

Introduction Respiratory tract infections caused by multidrug-resistant pathogens (beta-lactamase production microorganisms) are becoming a major concern for treatment constituting an additional burden for individual patients and for the Health Care System. Objective To determine the prevalence and etiology of resistant microorganisms responsible for lower respiratory tract infections in hospitalized patients. Methods A total of 100 bacterial isolates from patients diagnosed with respiratory infections were studied for three years in a Health Area (Emergency Unit, Pneumology Department and Intensive Care Service). The origin of the samples was: sputum, bronchial aspirate, pleural fluid, bronchoalveolar lavage and blood cultures. The study of antibacterial susceptibility (Walk away, Beckman) was determined using the CLSI broth microdilution method (Walk-Away Systems, Beckman) and the breakpoints were considered according to the Clinical Laboratory Standard Institute guidelines (CLSI) and EUCAST guidelines 2011. It was confirmed by diffusion method (disk and E-test), resistant isolates detected. Epidemiological and clinical data of patients were analyzed: age, gender, hospitalization in the previous three months, diabetes, Chronic Pulmonary Obstructive Disease (COPD), asthma, interstitial lung disease and treatment with antibiotics in the last month. Results Klebsiella pneumoniae was the most predominant bacterial species(32%), followed by Pseudomonas aeruginosa (12%), Serratia marcencens, Enterobacter spp and Escherichia coli. The prevalence of resistant bacterial isolates ESBL producers was 31%, being Pseudomonas aeruginosa the most predominant (44.2%), followed by Klebsiella pneumoniae (31.6%). No strains of Acinetobacter baumannii were isolated. Of the different clinical variables studied stand out from the point of view of respiratory infection, history of COPD and other variables the hospitalization and treatment history prior to admission. 5. Have a higher risk of infection by multi-drug resistant pathogens: patients with COPD, those who have had a hospitalization in the last 3 months and those who have taken at least one course of antibiotics. Conclusions We results are very similar to European studies, however we should not forget to make focus on the management of these patients, and the need for the implementation of strategies for infection control to prevent the spread of these strains.