Antibacterial resistance patterns and incidence of hospital-acquired Staphylococcus aureus bacteremia in a tertiary care educational hospital in Turkey: a perspective from 2001 to 2013

Background/aim: Staphylococcus aureus is an important nosocomial pathogen and a successful antimicrobial-resistance developer. In this study we retrospectively evaluated the resistance patterns and incidence of microbiologically confirmed nosocomial bacteremia (MCNB) related S. aureus strains between 2001 and 2013. Materials and methods: Any patient in whom S. aureus was isolated in at least one set of blood cultures (sent to the bacteriology laboratory 72 h after hospital admission) was considered to have MCNB. Results: The methicillin-resistant S. aureus (MRSA) rate in 2001 was 73.8% whereas it was 36.2% in 2013. When the 2001-2003 and 2011?2013 periods were compared, resistance to oxacillin, levofloxacin, gentamicin, erythromycin, and clindamycin decreased significantly (P < 0.05). When we evaluated the total S. aureus, MRSA, and methicillin-sensitive S. aureus (MSSA) bacteremia rates per 1000 days and 1000 patients, there was an increase in the 2004?2005 period, which was followed by a slight decrease until 2013 (P < 0.05). There was a plateau in MCNB-related S. aureus rates between 2008 and 2011. Conclusion: There was a decrease in overall S. aureus and MRSA bacteremia incidence as well as MRSA rates except for a plateau between 2008 and 2011. This steady decrease in the resistance rates is most probably due to the 2003 budget application and application of antimicrobial stewardship.