Identification of a Novel Clone, ST736, Among Enterococcus Faecium Clinical Isolates and Its Association With Daptomycin Nonsusceptibility

Authors

Guiqing Wang, Department of Pathology, New York Medical College, Valhalla, New York, USA Department of Pathology and Clinical Laboratories, Westchester Medical Center, Valhalla, New York, USA guiqing_wang@nymc.edu.
Sitharthan Kamalakaran, Philips Research North America, Briarcliff Manor, New York, USA.
Abhay Dhand, Department of Medicine, New York Medical College, Valhalla, New York, USA.
Weihua Huang, Department of Pathology, New York Medical College, Valhalla, New York, USA.
Caroline Ojaimi, Department of Pathology, New York Medical College, Valhalla, New York, USA.
Jian Zhuge, Department of Pathology and Clinical Laboratories, Westchester Medical Center, Valhalla, New York, USA.
Leslie Lee Yee, Department of Pharmacy, Westchester Medical Center, Valhalla, New York, USA.
Pramod Mayigowda, Philips Research North America, Briarcliff Manor, New York, USA.
Pavan Kumar Surendraiah, Department of Pathology, New York Medical College, Valhalla, New York, USA.
Nevenka Dimitrova, Philips Research North America, Briarcliff Manor, New York, USA.
John T. Fallon, Department of Pathology, New York Medical College, Valhalla, New York, USA Department of Medicine, New York Medical College, Valhalla, New York, USA Department of Pathology and Clinical Laboratories, Westchester Medical Center, Valhalla, New York, USA.

Author Type(s)

Faculty

DOI

10.1128/AAC.02683-14

Journal Title

Antimicrobial Agents and Chemotherapy

First Page

4848

Last Page

54

Document Type

Article

Publication Date

8-1-2014

Abstract

Resistance to daptomycin in enterococcal clinical isolates remains rare but is being increasingly reported in the United States and worldwide. There are limited data on the genetic relatedness and microbiological and clinical characteristics of daptomycin-nonsusceptible enterococcal clinical isolates. In this study, we assessed the population genetics of daptomycin-nonsusceptible Enterococcus faecium (DNSE) clinical isolates by multilocus sequence typing (MLST) and whole-genome sequencing analysis. Forty-two nonduplicate DNSE isolates and 43 randomly selected daptomycin-susceptible E. faecium isolates were included in the analysis. All E. faecium isolates were recovered from patients at a tertiary care medical center in suburban New York City from May 2009 through December 2013. The daptomycin MICs of the DNSE isolates ranged from 6 to >256 μg/ml. Three major clones of E. faecium (ST18, ST412, and ST736) were identified among these clinical isolates by MLST and whole-genome sequence-based analysis. A newly recognized clone, ST736, was seen in 32 of 42 (76.2%) DNSE isolates and in only 14 of 43 (32.6%) daptomycin-susceptible E. faecium isolates (P < 0.0001). This report provides evidence of the association between E. faecium clone ST736 and daptomycin nonsusceptibility. The identification and potential spread of this novel E. faecium clone and its association with daptomycin nonsusceptibility constitute a challenge for patient management and infection control at our medical center.

Recommended Citation

Wang, G., Kamalakaran, S., Dhand, A., Huang, W., Ojaimi, C., Zhuge, J., Yee, L. L., Mayigowda, P., Surendraiah, P. K., Dimitrova, N., & Fallon, J. T. (2014). Identification of a Novel Clone, ST736, Among Enterococcus Faecium Clinical Isolates and Its Association With Daptomycin Nonsusceptibility. Antimicrobial Agents and Chemotherapy, 58 (8), 4848-54. https://doi.org/10.1128/AAC.02683-14