Roel H T Nijhuis, Annemarie J L Weersink, Frouke Stegeman-Heining, Annelies E Smilde, Damian C Melles
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引用次数: 0
Abstract
Objectives: Our setting was challenged with an outbreak of different vancomycin resistant Enterococcus faecium (VREfm) including vanA and/or vanB containing isolates. Remarkably, it was observed that screening by use of a vanA and vanB real-time PCR on overnight enriched specimens from time to time tested positive for VanB with very low Ct-values, whereas VREfm-specific enrichment cultures remained negative. Here, we describe the analysis of the diagnostic results leading to adaptation of the diagnostic algorithm.
Methods: Per specimen of each patient, results of the vanA and vanB screening PCR and of the VREfm-specific culture (Brilliance VRE) were collected and combined with genotyping data of the identified VREfm isolates. During the outbreak, a second VREfm-specific culture medium (CHROMagar VRE) was introduced, and results were compared to the results obtained with Brilliance VRE agar.
Results: Thirty-five patients were identified as VREfm-carrier, in which four different strains were identified comprising vanA (STnew-CT7088) and/or vanB (ST80-CT1065, ST117-CT7117 and ST117-CT7118). Complementing results of PCR, culture and genotyping revealed that culture with Brilliance VRE agar was inadequate for detection of the vanB ST117 isolates identified, irrespective of vancomycin MIC values. In contrast, CHROMagar VRE was able to correctly detect these vanB ST117 isolates and other tested isolates.
Conclusions: Our data showed that the vanB ST117 containing isolates were inadequately detected by the VREfm-specific culture media, possibly contributing to unnoticed spread of VREfm. For this reason, CHROMagar VRE was evaluated during the outbreak and subsequently implemented in routine diagnostics, replacing Brilliance VRE agar.
期刊介绍：
The Journal of Hospital Infection is the editorially independent scientific publication of the Healthcare Infection Society. The aim of the Journal is to publish high quality research and information relating to infection prevention and control that is relevant to an international audience.
The Journal welcomes submissions that relate to all aspects of infection prevention and control in healthcare settings. This includes submissions that:
provide new insight into the epidemiology, surveillance, or prevention and control of healthcare-associated infections and antimicrobial resistance in healthcare settings;
provide new insight into cleaning, disinfection and decontamination;
provide new insight into the design of healthcare premises;
describe novel aspects of outbreaks of infection;
throw light on techniques for effective antimicrobial stewardship;
describe novel techniques (laboratory-based or point of care) for the detection of infection or antimicrobial resistance in the healthcare setting, particularly if these can be used to facilitate infection prevention and control;
improve understanding of the motivations of safe healthcare behaviour, or describe techniques for achieving behavioural and cultural change;
improve understanding of the use of IT systems in infection surveillance and prevention and control.
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