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The aim of the study was to assess the epidemiology, the incidence of multidrug-resistant bacteria and bloodstream infections’ (BSIs) seasonality in a university hospital. This retrospective study was carried out in the University General Hospital of Patras, Greece, during 2011–13 y. Blood cultures from patients with clinical presentation suggestive of bloodstream infection were performed by the BacT/ALERT System. Isolates were identified by Vitek 2 Advanced Expert System. Antibiotic susceptibility testing was performed by the disk diffusion method and E-test. Resistance genes (<italic>mec</italic>A in staphylococci; <italic>van</italic>A/<italic>van</italic>B/<italic>van</italic>C in enterococci; <italic>bla</italic>KPC/<italic>bla</italic>VIM/<italic>bla</italic>NDM in <italic>Klebsiella</italic> spp.) were detected by PCR. In total, 4607 (9.7%) blood cultures were positive from 47451 sets sent to Department of Microbiology, representing 1732 BSIs. Gram-negative bacteria (52.3%) were the most commonly isolated, followed by Gram-positive (39.5%), fungi (6.6%) and anaerobes bacteria (1.8%). The highest contamination rate was observed among Gram-positive bacteria (42.3%). Among 330 CNS and 150 <italic>Staphylococcus aureus</italic>, 281 (85.2%) and 60 (40.0%) were <italic>mec</italic>A-positive, respectively. From 113 enterococci, eight were <italic>van</italic>A, two <italic>van</italic>B and two <italic>van</italic>C-positives. Of the total 207 carbapenem-resistant <italic>Klebsiella pneumoniae</italic> (73.4%), 202 carried <italic>bla</italic>KPC, four <italic>bla</italic>KPC and <italic>bla</italic>VIM and one <italic>bla</italic>VIM. A significant increase in monthly BSIs’ incidence was shown (R2: 0.449), which may be attributed to a rise of Gram-positive BSIs (R2: 0.337). Gram-positive BSIs were less frequent in spring (<italic>P</italic> &lt; 0.001), summer (<italic>P</italic> &lt; 0.001), and autumn (<italic>P</italic> &lt; 0.001), as compared to winter months, while Gram-negative bacteria (<italic>P</italic> &lt; 0.001) and fungi (<italic>P</italic> &lt; 0.001) were more frequent in summer months. BSIs due to methicillin resistant <italic>S. aureus</italic> and carbapenem-resistant Gram-negative bacteria increased during the study period. The increasing incidence of BSIs can be attributed to an increase of Gram-positive BSI incidence, even though Gram-negative bacteria remained the predominant ones. Seasonality may play a role in the predominance of Gram-negative’s BSI.
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The aim of the study was to assess the epidemiology, the incidence of multidrug-resistant bacteria and bloodstream infections’ (BSIs) seasonality in a university hospital. This retrospective study was carried out in the University General Hospital of Patras, Greece, during 2011–13 y. Blood cultures from patients with clinical presentation suggestive of bloodstream infection were performed by the BacT/ALERT System. Isolates were identified by Vitek 2 Advanced Expert System. Antibiotic susceptibility testing was performed by the disk diffusion method and E-test. Resistance genes (mecA in staphylococci; vanA/vanB/vanC in enterococci; blaKPC/blaVIM/blaNDM in Klebsiella spp.) were detected by PCR. In total, 4607 (9.7%) blood cultures were positive from 47451 sets sent to Department of Microbiology, representing 1732 BSIs. Gram-negative bacteria (52.3%) were the most commonly isolated, followed by Gram-positive (39.5%), fungi (6.6%) and anaerobes bacteria (1.8%). The highest contamination rate was observed among Gram-positive bacteria (42.3%). Among 330 CNS and 150 Staphylococcus aureus, 281 (85.2%) and 60 (40.0%) were mecA-positive, respectively. From 113 enterococci, eight were vanA, two vanB and two vanC-positives. Of the total 207 carbapenem-resistant Klebsiella pneumoniae (73.4%), 202 carried blaKPC, four blaKPC and blaVIM and one blaVIM. A significant increase in monthly BSIs’ incidence was shown (R2: 0.449), which may be attributed to a rise of Gram-positive BSIs (R2: 0.337). Gram-positive BSIs were less frequent in spring (P < 0.001), summer (P < 0.001), and autumn (P < 0.001), as compared to winter months, while Gram-negative bacteria (P < 0.001) and fungi (P < 0.001) were more frequent in summer months. BSIs due to methicillin resistant S. aureus and carbapenem-resistant Gram-negative bacteria increased during the study period. The increasing incidence of BSIs can be attributed to an increase of Gram-positive BSI incidence, even though Gram-negative bacteria remained the predominant ones. Seasonality may play a role in the predominance of Gram-negative’s BSI.

Trends of Bloodstream Infections in a University Greek Hospital during a Three-Year Period: Incidence of Multidrug-Resistant Bacteria and Seasonality in Gram-negative Predominance

Polish Journal of Microbiology

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

The aim of the study was to assess the epidemiology, the incidence of multidrug-resistant bacteria and bloodstream infections’ (BSIs) seasonality in a...

Trends of Bloodstream Infections in a University Greek Hospital during a Three-Year Period: Incidence of Multidrug-Resistant Bacteria and Seasonality in Gram-negative Predominance

Publicado en línea: 28 jun 2017

Páginas: 171 - 180

Recibido: 18 jun 2016

Aceptado: 24 nov 2016

DOI: https://doi.org/10.5604/pjm-2017-171

Palabras clave
bacteremia, non-, carbapenem-resistance, methicillin resistant vancomycin resistant enterococci (VRE)

© 2017 FEVRONIA KOLONITSIOU et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Trends of Bloodstream Infections in a University Greek Hospital during a Three-Year Period: Incidence of Multidrug-Resistant Bacteria and Seasonality in Gram-negative Predominance

Publicado en línea: 28 jun 2017

Páginas: 171 - 180

Recibido: 18 jun 2016

Aceptado: 24 nov 2016

DOI: https://doi.org/10.5604/pjm-2017-171

Palabras clavebacteremia, non-, carbapenem-resistance, methicillin resistant vancomycin resistant enterococci (VRE)

© 2017 FEVRONIA KOLONITSIOU et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Palabras clave
bacteremia, non-, carbapenem-resistance, methicillin resistant vancomycin resistant enterococci (VRE)