Frequency, Local Dynamics, and Genomic Characteristics of ESBL-Producing Escherichia coli Isolated From Specimens of Hospitalized Horses

Abstract

Previous research identified veterinary clinics as hotspots with respect to accumulation and spread of multidrug resistant extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (EC). Therefore, promoting the prudent use of antibiotics to decrease selective pressure in that particular clinical environment is preferable to enhance biosecurity for animal patients and hospital staff. Accordingly, this study comparatively investigated the impact of two distinct perioperative antibiotic prophylaxis (PAP) regimens (short-term versus prolonged) on ESBL-EC carriage of horses subjected to colic surgery. While all horses received a combination of penicillin/gentamicin (P/G) as PAP, they were assigned to either the “single-shot group” (SSG) or the conventional “5-day group” (5DG). Fecal samples collected on arrival (t0), on the 3rd (t1) and on the 10th day after surgery (t2) were screened for ESBL-EC. All isolates were further investigated using whole genome sequences. In total, 81 of 98 horses met the inclusion criteria for this study. ESBL-EC identified in samples available at t0, t1 and t2 were 4.8% (SSG) and 9.7% (5DG), 37% (SSG) and 47.2% (5DG) as well as 55.6% (SSG) and 56.8% (5DG), respectively. Regardless of the P/G PAP regimen, horses were 9.12 times (95% CI 2.79–29.7) more likely to carry ESBL-EC at t1 compared to t0 (p < 0.001) and 15.64 times (95% CI 4.57–53.55) more likely to carry ESBL-EC at t2 compared to t0 (p < 0.001). ESBL-EC belonging to sequence type (ST) 10, ST86, ST641, and ST410 were the most prevalent lineages, with blaCTX–M–1 (60%) being the dominant ESBL gene. A close spatio-temporal relationship between isolates sharing a particular ST was revealed by genome analysis, strongly indicating local spread. Consequently, hospitalization itself has a strong impact on ESBL-EC isolation rates in horses, possibly masking differences between distinct PAP regimens. The results of this study reveal accumulation and spread of multi-drug resistant ESBL-EC among horses subjected to colic surgery with different P/G PAP regimens, challenging the local hygiene management system and work-place safety of veterinary staff. Moreover, the predominance of particular ESBL-EC lineages in clinics providing health care for horses needs further investigation.

Longitudinal study of the short- and long-term effects of hospitalisation and oral trimethoprim-sulfadiazine administration on the equine faecal microbiome and resistome

“…Implementation of an effective infection prevention protocol in the equine hospital in the current study might have prevented or reduced the dissemination of antimicrobial-resistant bacteria and ARGs to hospitalised horses. However, previous studies using culture-based or PCR techniques have shown that antimicrobial-resistant E. coli bacteria increase in the faeces of horses, independent of antimicrobial administration, within days of hospitalisation [55][56][57][58][59][60]. One study compared the duration of faecal shedding of resistant E. coli after antimicrobial treatment between hospitalised horses and non-hospitalised horses [61].…”

Does colonization with MRSA, ESBL – producing Enterobacteriaceae, and/or Acinetobacter baumannii – increase the risk for postoperative surgical site infection?

“…Nevertheless previous research revealed veterinary clinics as ‘hotspots’ for local MDR pathogen accumulation and transmission (Apostolakos et al., 2017 ; Kauter et al., 2021 ; Walther et al., 2018a ; Wright et al., 2005 ). As our results are in line with recent reports, the development of appropriate hygiene strategies that take into account the special challenges of equine medicine (e.g.…”

“…Additionally, infected laparotomy incisions were infected significantly more often with ESBL‐E and A. baumannii than the infected wounds of injured horses. The protection of the incisional wound from residing MDRP from the mucosal surfaces and/or the environment seems crucial to prevent SSI, especially because earlier studies identified 10.7% of admitted horses being positive for ESBL‐E and 3.5% for MRSA (Kauter et al., 2021 ; Walther et al., 2018a ; Walther et al., 2018b ). A simple wound covering was placed after the laparotomy and renewed after recovery.…”

Antimicrobial and Biocide Resistance among Canine and Feline Enterococcus faecalis, Enterococcus faecium, Escherichia coli, Pseudomonas aeruginosa, and Acinetobacter baumannii Isolates from Diagnostic Submissions

“…The bacterial isolates investigated in this study were identified by standard microbiological procedures as previously described [ 52 , 53 , 54 , 60 , 61 , 62 ]. In brief, the samples were analysed by aerobic cultivation after direct inoculation on suitable agar plates (all agar purchased from Oxoid, Wesel, Germany).…”