Epidemiology and antimicrobial susceptibility trends of methicillin-resistant Staphylococcus aureus in a tertiary hospital

Introduction: Staphylococcus aureus is a major cause of health care associated infections worldwide. Objective: The aim of this work was to evaluate epidemiological characteristics and antimicrobial susceptibility of Methicillin-resistant S . aureus (MRSA) strains isolates from infections in a Brazilian tertiary hospital. Methods: Clinical and epidemiological data of the patients were collected. Bacterial strains were isolated and identified using the classical identification tests. Antimicrobial susceptibility assays were performed using the disc-diffusion method. Findings: A total of 590 samples of S. aureus were isolated from patients and 42.5% were characterized as MRSA. Considering the clinical specimens, most of samples were isolated from blood and tracheal secretion, catheter tip, surgical site swabs, wound secretion, exudates and urine. Overall, a high frequency of resistance was observed against ciprofloxacin, clindamycin, erythromycin, amikacin, gentamicin, trimethoprim-sulfamethoxazole, tetracycline and chloramphenicol. Association between death and multidrug-resistance in elderly patients, and death and occurrence of bacteremia by multidrug-resistant MRSA was observed. Conclusions: Our data are highly relevant for surveillance systems and to map on a wider scale the dynamics of circulation of MRSA and raise discussions on containment strategies and rational use of empiric chemotherapy.