Retrospective analysis of isolated respiratory pathogens spectrum and antimicrobial resistance trends: a single center ten-years follow-up

<bold>Introduction:</bold> Bacterial resistance to antibiotics represents one of the biggest therapeutic problems resulting in increased morbidity and mortality, as a consequence of irrational antibiotic use and rapid bacterial adaptation. <bold>Aims and objectives:</bold> We aimed to asses our local respiratory pathogens spectrum and antimicrobial resistance trends. <bold>Methods:</bold> We retrospectively analyzed the bacterial spectrum and antimicrobial resistance (assesed by disc diffusion method) from the respiratory tract specimens (nasopharyngeal swab, sputum, bronchoalveolar lavage) obtained during the previous twelve months at our clinic. The results were compared with those from the year 2012. <bold>Results:</bold> From a total of 1103 specimens, 277 (25.1%) were positive, while 73.65% of them were Gram-negative bacteria. Enterobacteriaceae make 37.7% of Gram-negative isolates with ESBL positivity in 31.2% (especially Klebsiella, in 40.9%) of cases. Pseudomonas aeruginosa makes 38.2% of isolates, being resistant to Piperacillin/tazobactam in 24.4% of cases - lower rate than in previous results (43%). The rate of resistance to Amikacin is relatively low: 6.4%. Staphylococcus aureus makes 75% of Gram-positive bacteria, while 20% are Methicillin resistant (significantly higher rate than in previous results: 4%) and 30.9% resistant to Levofloxacin. Streptococcus pneumoniae was present in less than 4% of all isolates. <bold>Conclusions:</bold> Local Gram-negative bacterial spectrum and antimicrobial resistance is probably a consequence of the irrational use of broad-spectrum antibiotics. The obtained results can contribute to an adequate choice of empiric antibiotic therapy and lowering complications rate.