Clonality and antimicrobial susceptibility of methicillin-resistant Staphylococcus aureus at the University Hospital Zurich, Switzerland between 2012 and 2014

Annals of Clinical Microbiology and Antimicrobials

Research

Gabriela Senn¹  Miguel Palheiros Marques¹  Annelies S Zinkernagel¹  Alexandra Furrer¹  Nadja Leimer¹  Kati Seidl¹  Anne Holzmann-Bürgel¹  Reinhard Zbinden² 

[1] Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Rämistr. 100, RAE U, 8091, Zurich, Switzerland;Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland;

关键词: MRSA;    Epidemiology;    Antibiotic susceptibility;    Molecular typing;   

DOI  :  10.1186/s12941-015-0075-3

 received in 2014-09-26, accepted in 2015-03-05,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundMethicillin-resistant Staphylococcus aureus (MRSA) is a global epidemic threat. The aim of this study was to determine which globally known MRSA lineages are currently present at our tertiary care hospital in Switzerland, a hospital with low MRSA prevalence. In light of the increasing prevalence of multi drug resistance including vancomycin resistance we also assessed antibiotic susceptibilities.MethodsThe 146 MRSA strains collected over two years (March 2012 until February 2014) at the University Hospital Zurich, Switzerland, were analyzed by PFGE analysis of SmaI digests in combination with spa-typing. In addition, representative isolates were analyzed by multi locus sequence typing (MLST). Susceptibilities to eight antibiotics were assessed using the Kirby-Bauer disc diffusion method.ResultsIsolates showed resistance to erythromycin (48%), ciprofloxacin (43%), clindamycin (31%), tetracycline (22%), and gentamicin (16%). All isolates were susceptible to vancomycin, 95% were susceptible to sulfamethoxazole/trimethoprim and rifampicin, respectively. PFGE analysis revealed 22 different patterns, with four major patterns that accounted for 53.4% of all MRSA isolates, and seven sporadic patterns. Spa typing revealed 50 different spa types with the predominant types being t008 (14%), t002 (10%), and t127 (9%). 82% of the MRSA isolates could be assigned to six clonal complexes (CCs) namely CC1 (10%), CC5 (23%), CC8 (18%), CC22 (17%), CC30 (11%), and CC45 (3%) based on spa-types, PFGE patterns, and MLST. Two isolates could not be typed by either PFGE analysis or spa-typing and three isolates had spa-types that have not yet been described.ConclusionsThe combination of the two typing methods was more discriminatory as compared to the use of a single method. Several of the lineages that are predominant in Europe are present in our hospital. Resistances to antibiotics have decreased in comparison to a study conducted between 2004 and 2006.

【 授权许可】

CC BY   
© Seidl et al.; licensee BioMed Central. 2015