Emergence and Transmission of Daptomycin and Vancomycin-Resistant Enterococci Between Patients and Hospital Rooms

Abstract

Background Vancomycin-resistant enterococci (VRE) are a major cause of morbidity and mortality in immunocompromised patients. Tracking the dissemination of VRE strains is crucial to understand the dynamics of emergence and spread of VRE in the hospital setting. Methods Whole genome sequencing (WGS) and phylogenetic analyses were performed to identify dominant VRE strains and potential transmission networks between 35 patients with VRE-positive rectal swabs and their rooms (main rooms and bathrooms) on the leukemia (LKM) and the hematopoietic cell transplant (HCT) floors. Sequence types (STs), drug resistance genes, and patients’ outcomes were also determined. Results A total of 89 VRE strains grouped into 10 different STs, of which newly described STs were isolated from both floors (ST736, ST494, ST772, and ST1516). We observed highly genetically related strains transmitted between rooms, floors, and time periods in an average period of 39 days (ranging from 3 to 90 days). Of 5 VRE bacteremia events, 3 strains were lacking the pili operon fms14–17–13 (ST203) and the remaining 2 were resistant to daptomycin (DAP; ST736, ST664). Of 10 patients harboring DAP-resistant strains, only 2 were exposed to DAP within 4 months before strain recovery. Conclusions Our comparisons of VRE strains derived from the environment and immunocompromised patients confirmed horizontal transfer of highly related genetic lineages of multidrug-resistant (particularly to DAP) VRE strains between HCT and LKM patients and their room environment. Implementing WGS can be useful in distinguishing VRE reservoirs where interventions can be targeted to prevent and control the spread of highly resistant organisms.

Previous antibiotic therapy as independent risk factor for the presence of vancomycin-resistant enterococci in surgical inpatients. Results from a matched case-control study

“…The most frequent MLST type in our study was ST117 within clonal complex 17 that after 2010 spread in health care settings in Germany [ 39 ]. In our setting the knowledge of the sequence type, however, in most cases was not helpful to track the in-hospital spread of individual VRE isolates, and therefore did not aid in the identification of potential sources of VRE, as this has been described in a recent study using whole genome sequencing for typing of VRE isolates [ 40 ]. In the dialysis group ST117 (42.8%) was significantly (p = 0,045) less frequent compared to the frequencies of ST117 in the other risk groups, which was in the range of 57.7–75% of all VRE isolates.…”

Hospital water as the source of healthcare-associated infection and antimicrobial-resistant organisms

“…Transmission of daptomycin-resistant strains of VRE were studied in an American cancer centre to understand the potential spread between patients and their environment. It was found that there was horizontal transfer of genetically related strains of VRE between patients on different floors of the hospital and within their room environment [13]. Future research is required to understand the influence of outlet design on the spread of pathogen contamination, and on the effectiveness of different disinfection and control approaches.…”

“…Common OPPPs include Legionella spp., nontuberculous mycobacteria and Pseudomonas aeruginosa [8]. These microorganisms form biofilms on the surface of pipes and water-related devices that can also provide refuge to pathogens not typically associated with drinking water including Staphylococcus aureus , Enterobacteriaceae, Klebsiella pneumoniae and Escherichia coli [9–14 ▪ ]. Biofilms provide protection against unfavourable environmental conditions including disinfection processes and deliver the ideal environment for the transfer of antimicrobial resistance genetic elements [10 ▪ ,15].…”

Phage Cocktails with Daptomycin and Ampicillin Eradicates Biofilm-Embedded Multidrug-Resistant Enterococcus faecium with Preserved Phage Susceptibility

“…Daptomycin (DAP) is a preferred treatment for serious VRE infections and has demonstrated rapid biofilm penetration using fluorescent visualization [ 11 , 12 , 13 ]. Unfortunately, DAP-nonsusceptible (DNS) and DAP-susceptible dose-dependent (SDD) phenotypes are quickly emerging [ 14 , 15 , 16 , 17 , 18 ]. Substitutions in LiaS and LiaR of the LiaFSR pathway, enhances DAP’s selection for resistance, rendering the isolate unresponsive to DAP monotherapy, regardless of dose exposure [ 19 , 20 ].…”