Detection of mcr-1-Carrying Escherichia coli Causing Bloodstream Infection in a New York City Hospital: Avian Origins, Human Concerns?

Abstract

The spread of mcr-1 in the United States remains poorly defined. mcr-1-producing Escherichia coli that also carried blaSHV-12 was detected in a hospitalized patient. No additional cases were identified during screening of 801 Gram-negative isolates. Genomic sequencing identified an IncX4 mcr-1- harboring plasmid and ST117 clonal background associated with avian pathogenic E coli.

Discovery of multi-drug resistant, MCR-1 and ESBL-coproducing ST117 Escherichia coli from diseased chickens in northeast China

“…To our surprise, three different variants of ESBL (namely, bla TEM-1B , bla TEM-99 and bla CTX-M-14 ) are present together with a newly-identified mcr-1 colistin resistance determinant in a single avian E. coli. Prior to this study, ST117 E. coli was only reported to contain mcr-1 in gut flora of children, China [30], and involved in bloodstream infections, in New York [32]. To the best our knowledge, our finding might define, for the first time, cooccurrence of integron-carrying ESBL (bla TEM-1B , bla TEM-99 and bla -CTX-M-14 ) and plasmid-bearing mcr-1 in a single ST117 E. coli isolate with avian origin from China, from 2011 to 2012.…”

“…Additionally, extended-spectrum b-lactamase (ESBL) also can be coproduced with MCR-1 in a single bacterial cell [26][27][28][29], indicating the complexity in the profile of MCR-1-participating antibiotic resistance. As for ST117 of E. coli [30], it is an endemic clone with avian origins [31], but human concerns [32]. In fact, the mcr-1-carrying ST117 has been recorded in inpatients with bloodstream infections [32] and predominantly inhabits in gut flora of children [30].…”

“…As for ST117 of E. coli [30], it is an endemic clone with avian origins [31], but human concerns [32]. In fact, the mcr-1-carrying ST117 has been recorded in inpatients with bloodstream infections [32] and predominantly inhabits in gut flora of children [30]. However, the ST117 of E. coli co-producing ESBL and MCR-1 in poultry is largely unknown.…”

Adaptation of Acinetobacter baumannii to colistin exposure: Laboratory mimicking of a clinical case

“…In our study, after 25 days of colistin treatment, colistin resistant A. baumannii was isolated from intra-abdominal fluid of the patient. Colistin exposure is found to be the main risk factor for development of colistin resistance by previous studies (2, 8). We mimicked the effects of colistin exposure in the laboratory by measuring MIC and expressions of pmrCAB .…”

“…The increase of colistin-resistance in Acinetobacter baumannii is a great concern in various regions of the world such as Asia, Europe, and North and South America (1). Exposure to colistin is considered as the most significant factor for emerging of colistin resistance (2), however, details of the in vivo response of A. baumannii to colistin exposure, such as the number of days for development of resistance was not described. The molecular studies about colistin resistance indicated two main mechanisms: modifications in lipid A structure and complete loss of LPS (3).…”