Mechanisms of quinolone resistance in Escherichia coli isolated from companion animals, pet-owners, and non-pet-owners

Antimicrobial Resistance in Escherichia coli Isolated from Healthy Dogs and Cats in South Korea, 2020-2022

The occurrence of antimicrobial-resistant bacteria in companion animals poses public health hazards globally. This study aimed to evaluate the antimicrobial resistance profiles and patterns of commensal E. coli strains obtained from fecal samples of healthy dogs and cats in South Korea between 2020 and 2022. In total, 843 E. coli isolates (dogs, n = 637, and cats, n = 206) were assessed for susceptibility to 20 antimicrobials. The resistance rates of the most tested antimicrobials were significantly higher in dog than in cat isolates. Cefalexin (68.9%) demonstrated the highest resistance rates, followed by ampicillin (38.3%), tetracycline (23.1%), and cefazolin (18.7%). However, no or very low resistance (0-0.6%) to amikacin, imipenem, piperacillin, and colistin was found in both dog and cat isolates. Overall, 42.3% of the isolates exhibited multidrug resistance (MDR). MDR in isolates from dogs (34.9%) was significantly higher than in those from cats (20.9%). The main components of the resistance patterns were cefalexin and ampicillin in both dog and cat isolates. Additionally, MDR patterns in isolates from dogs (29.2%) and cats (16%) were shown to encompass five or more antimicrobials. Multidrug-resistant commensal E. coli could potentially be spread to humans or other animals through clonal or zoonotic transmission. Therefore, the incidence of antimicrobial resistance in companion animals highlights the urgent need to restrict antimicrobial resistance and ensure the prudent use of antimicrobials in Korea.

Quinolone-resistant Escherichia coli at the interface between humans, poultry and their shared environment- a potential public health risk

BACKGROUND

Commensal Escherichia coli residing in the guts of humans and animals are reservoirs of multidrug resistance (MDR) genes, including quinolone resistance genes, in humans and poultry. This study aimed to characterize quinolones resistance in E. coli recovered from poultry workers, chickens, and poultry farm/market environments in Abuja, Nigeria.

METHODS

This was a cross-sectional study conducted between December 2018 and April 2019 comprising poultry workers, chickens and their poultry farm/market environments. This study characterized E. coli isolates from stool, faecal and environmental samples using antimicrobial susceptibility testing and whole-genome sequencing methods. Core-genome multilocus sequences-based phylogeny was used to determine the relatedness between quinolone-resistant E. coli isolates. Data were analyzed using descriptive statistics.

RESULTS

Of 110 E. coli isolates, quinolone-resistant phenotypes were observed in 68.2% (n = 75) isolates. Whole-genome sequencing detected plasmid-mediated quinolone resistance (PMQR) genes in 63.6% (n = 70) isolates. The most prevalent PMQR gene detected in 56 of these 70 E. coli isolates was qnrS1, followed by qnrB19 in 14 isolates and aac(6')-lb-cr in two isolates. Fifteen ciprofloxacin and 19 nalidixic acid-resistant isolates respectively showed double mutations in the quinolone-resistance determining regions (QRDRs) of gyrA, with single or double mutations in parC, and a single mutation in parE. The most prevalent amino-acid substitutions observed were S83L + D87N in gyrA (46.5%, n = 20), S80I in parC (51.2%, n = 22) and S458A in parE (14%, n = 6). About 2.9% (2/70) of PMQR isolates were extended-spectrum beta-lactamase (ESBL) producers while 2.9% (2/70) had plasmid-mediated colistin resistance (PMCR) genes.

CONCLUSIONS

PMQR genes were prevalent in E. coli isolates recovered from healthy humans, chickens and poultry farm/market environments. PMCR genes (mcr-1.1) occurred in PMQR-positive isolates recovered from manure and drinking water originating from poultry farm/market environments. It was found that the gene encoding ESBL coexisted with qnrS-positive isolates of human and avian origin. Horizontal transfer of PMQR genes among E. coli isolates in the human-poultry-environment interface has public health implications for the spread of antimicrobial resistance. Relevant government agencies should enforce regulations to restrict the use of critically important antimicrobials in poultry production.

Bacterial Prevalence in Skin, Urine, Diarrheal Stool, and Respiratory Samples from Dogs

The emergence of bacterial infections in companion animals is a growing concern as humans can also be infected through the transmission of pathogenic bacteria. Because there have been few studies conducted on companion animals, the extent and significance of prevalence in veterinary practices remain unknown. This is the first nationwide surveillance report aimed at elucidating the prevalence pattern and associated infections of isolated bacteria from dogs in Korea. Bacterial isolates were collected from seven different laboratories participating in the Korean Veterinary Antimicrobial Resistance Monitoring System from 2018 to 2019. The samples were obtained from the diarrheal stool, skin/ear, urine, and respiratory samples of veterinary hospital-visited dogs. Isolation and identification of bacterial species was carried out using a bacterial culture approach and then confirmed with matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF) and polymerase chain reaction (PCR). Out of 3135 isolates in dogs, 1085, 1761, 171, and 118 were extracted from diarrheal stool, skin/ear, urine, and respiratory samples, respectively. The overall prevalence of bacteria was higher among two age groups (1-5 and 6-10 years) with a 66.5 percent prevalence. This study showed that Escherichia coli was the most prevalent species among isolated bacterial species of diarrheal and urine origin, whereas Staphylococcus pseudintermedius was the most prevalent among skin and respiratory sample isolates. The data on the prevalence of bacteria for each dog specimen could provide basic information to estimate the extent of bacterial infection and antimicrobial resistance development and to guide veterinarians in therapeutic decisions in clinical practices throughout Korea.

TEM,CTX-M,SHV Genes in ESBL-Producing Escherichia coli and Klebsiella pneumoniae Isolated from Clinical Samples in a County Clinical Emergency Hospital Romania-Predominance of CTX-M-15

Background: CTX-M betalactamases have shown a rapid spread in the recent years among Enterobacteriaceae and have become the most prevalent Extended Spectrum Beta-Lactamases (ESBLs) in many parts of the world. The introduction and dissemination of antibiotic-resistant genes limits options for treatment, increases mortality and morbidity in patients, and leads to longer hospitalization and expensive costs. We aimed to identify the beta-lactamases circulating encoded by the genes bla_CTX-M-15, bla_SHV-1 and bla_TEM-1 in Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) strains. Furthermore, we established the associated resistance phenotypes among patients hospitalized in the Intensive Care Unit (ICU) from County Clinical Emergency Hospital of Craiova, Romania. Methods: A total of 46 non-duplicated bacterial strains (14 strains of E. coli and 32 strains of K. pneumoniae), which were resistant to ceftazidime (CAZ) and cefotaxime (CTX) by Kirby–Bauer disk diffusion method, were identified using the automated VITEK2 system. Detection of ESBL-encoding genes and other resistance genes was carried out by PCR. Results. E. coli strains were resistant to 3rd generation cephalosporins and moderately resistant to quinolones, whereas K. pneumoniae strains were resistant to penicillins, cephalosporins, and sulfamides, and moderately resistant to quinolones and carbapenems. Most E. coli strains harbored bla_CTX-M-15 gene (13/14 strains), a single strain had the bla_SHV-1 gene, but 11 strains harbored bla_TEM-1 gene. The mcr-1 gene was not detected. We detected tet(A) gene in six strains and tet(B) in one strain. In K. pneumoniae strains we detected bla_CTX-M-15 in 23 strains, bla_SHV-₁ in all strains and bla_TEM-1 in 14 strains. The colistin resistance gene mcr-1 was not detected. The tetracycline gene tet(A) was detected in 11 strains, but the gene tet(B) was not detected in any strains. Conclusions. The development in antibiotic resistance highlights the importance of establishing policies to reduce antibiotic use and improving the national resistance surveillance system in order to create local antibiotic therapy guidelines.

Surveillance of antimicrobial-resistant Escherichia coli in Sheltered dogs in the Kanto Region of Japan

There is a lack of an established antimicrobial resistance (AMR) surveillance system in animal welfare centers. Therefore, the AMR prevalence in shelter dogs is rarely known. Herein, we conducted a survey in animal shelters in Chiba and Kanagawa prefectures, in the Kanto Region, Japan, to ascertain the AMR status of Escherichia coli  (E. coli) prevalent in shelter dogs. E. coli was detected in the fecal samples of all 61 and 77 shelter dogs tested in Chiba and Kanagawa, respectively. The AMR was tested against 20 antibiotics. E. coli isolates derived from 16.4% and 26.0% of samples from Chiba and Kanagawa exhibited resistance to at least one antibiotic, respectively. E. coli in samples from Chiba and Kanagawa prefectures were commonly resistant to ampicillin, piperacillin, streptomycin, kanamycin, tetracycline, and nalidixic acid; that from the Kanagawa Prefecture to cefazolin, cefotaxime, aztreonam, ciprofloxacin, and levofloxacin and that from Chiba Prefecture to chloramphenicol and imipenem. Multidrug-resistant bacteria were detected in 18 dogs from both regions; β-lactamase genes (blaTEM, blaDHA-1, blaCTX-M-9 group CTX-M-14), quinolone-resistance protein genes (qnrB and qnrS), and mutations in quinolone-resistance-determining regions (gyrA and parC) were detected. These results could partially represent the AMR data in shelter dogs in the Kanto Region of Japan.

Control strategies for the vertical gene transfer of quinolone ARGs in Escherichia coli through molecular modification and molecular dynamics

This study investigates the regulation of the vertical gene transfer of quinolones' antibiotic resistance genes (ARGs) through a combination of source modification and process control. In source prevention, 29 Escherichia coli (E. coli) DNA gyrase subunit A mutant proteins were constructed, the B-G mutant protein displayed the greatest reduction in binding effect (-25.98%). Based on this, a 3D-QSAR model was constructed, and LEV-2 and LEV-9 QNs derivatives were designed based on Levofloxacin (LEV), and their binding effect with B-G mutant protein was found be increased by 13.24% and 19.40%. The drug resistance mechanism of E. coli was explored based on molecular docking technology and protein hydrophobic interaction theory. Most of the amino acid resistance mutations changed from hydrophilic to lipophilic, which inhibited the binding of QNs to mutant protein A subunit, and further reduced the bactericidal effect of QNs. In process control, Huoxiang-Zhengqi, stroke-physiological saline solution (SPSS), and Lycium barbarum (L. barbarum) was found to be 164.82% higher than that of the blank control group. The purpose of this study is to provide a theoretical support for the joint regulation of QNs' ARGs in organisms and the research and development on green alternatives to QNs compounds.

Characterization of ESBL-Producing Escherichia coli and Klebsiella pneumoniae Isolated from Clinical Samples in a Northern Portuguese Hospital: Predominance of CTX-M-15 and High Genetic Diversity

Background: Enterobacteriaceae are major players in the spread of resistance to β-lactam antibiotics through the action of CTX-M β-lactamases. We aimed to analyze the diversity and genetic characteristics of ESBL-producing Escherichia coli and Klebsiella pneumoniae isolates from patients in a Northern Portuguese hospital. Methods: A total of 62 cefotaxime/ceftazidime-resistant E. coli (n = 38) and K. pneumoniae (n = 24) clinical isolates were studied. Identification was performed by MALDI-TOF MS. Antimicrobial susceptibility testing against 13 antibiotics was performed. Detection of ESBL-encoding genes and other resistance genes, phylogenetic grouping, and molecular typing (for selected isolates) was carried out by PCR/sequencing. Results: ESBL activity was detected in all 62 E. coli and K. pneumoniae isolates. Most of the ESBL-producing E. coli isolates carried a bla_CTX-M gene (37/38 isolates), being bla_CTX-M-15 predominant (n = 32), although bla_CTX-M-27 (n = 1) and bla_CTX-M-1 (n = 1) were also detected. Two E. coli isolates carried the bla_KPC2/3 gene. The lineages ST131-B2 and ST410-A were detected among the ESBL-producing blood E. coli isolates. Regarding the 24 ESBL-producing K. pneumoniae isolates, 18 carried a bla_CTX-M gene (bla_CTX-M-15, 16 isolates; bla_CTX-M-55, 2 isolates). All K. pneumoniae isolates carried bla_SHV genes, including ESBL-variants (bla_SHV-12 and bla_SHV-27, 14 isolates) or non-ESBL-variants (bla_SHV-11 and bla_SHV-28, 10 isolates); ten K. pneumoniae isolates also carried the bla_KPC2/3 gene and showed imipenem-resistance. ESBL-positive E. coli isolates were ascribed to the B₂ phylogenetic group (82%), mostly associated with ST131 lineage and, at a lower rate, to ST410/A. Regarding K. pneumoniae, the three international lineages ST15, ST147, and ST280 were detected among selected isolates. Conclusions: Different ESBL variants of CTX-M (especially CTX-M-15) and SHV-type (specially SHV-12) were detected among CTX/CAZ^RE. coli and K. pneumoniae isolates, in occasions associated with carbapenemase genes (bla_KPC2/3 gene).

Genomic characterisation of extended-spectrum β-lactamase-producing multidrug-resistant Escherichia coli in Rabat, Morocco

OBJECTIVES

Extended-spectrum β-lactamase (ESBL)-producing Escherichia coli are an increasingly significant cause of hospital- and community-acquired infections worldwide. Whereas several reports have highlighted their increased prevalence also in North African countries, genomic data on isolates associated with these infections are still scarce. This study aimed to provide data on ESBL-producing E. coli isolates from patients with extraintestinal infections at the Military Teaching Hospital Mohamed V of Rabat, Morocco.

METHODS

Whole-genome sequencing was carried out on 18 ESBL-producing extraintestinal pathogenic E. coli (ExPEC) isolates for analysis of phylogenomic evolution, virulence factors and antimicrobial resistance genes. Data were compared with ExPEC lineages from several surrounding countries using multilocus sequence typing (MLST) and single nucleotide polymorphism-based phylogenetic approaches.

RESULTS

The majority of E. coli isolates were ST131 (n = 15), followed by ST617 (n = 2) and a novel sequence type (ST10703) that is closely related to the pandemic ST405 clone. All ST131 isolates belonged to the O25b-ST131 pandemic clone. They harboured more virulence genes than their non-ST131 counterparts. IncF plasmid replicons and the bla_CTX-M-15 β-lactamase gene were identified in all isolates. No ESBL-producing E. coli isolates carried any known carbapenemase gene.

CONCLUSION

Our findings underscore the pre-eminence of ST131 as the major factor driving the expansion of ExPEC in the Rabat region while highlighting the potential links with isolates circulating in other neighbouring countries.

Global prevalence and molecular characterization of extended-spectrum β-lactamase producing-Escherichia coli in dogs and cats - A scoping review and meta-analysis

Antimicrobial resistance (AMR) represents a major threat to human and animal health. Part of the AMR dimension is the circulation of extended-spectrum β-lactamases producing-Escherichia coli (ESBL-E. coli), which is now commonly reported among companion animals. However, the global perspective of the prevalence and population structure of ESBL-E. coli circulating in dogs and cats has not been estimated limiting our understanding of their role in the dissemination of ESBL-E. coli. The aim of this study was to compare the prevalence of ESBL-E. coli between dogs and cats and across countries through meta-analysis. We also performed a scoping review to summarize the current knowledge on ESBL genes and E. coli clones circulating among companion animals. A total of 128 studies published in PubMed, Web of Science, and Scopus up to April 2020 were selected and contained information on prevalence and/or molecular characterization of ESBL genes and ESBL-E. coli clones. Our review shows an increase in the number of publications between 2000 and 2019, concentrated mainly in Europe. Prevalence varied across continents, ranging from 0.63% (Oceania) to 16.56% (Africa) in dogs and from 0% (Oceania) to 16.82% (Asia) in cats. Although there were twice as many studies reporting prevalence on dogs (n = 61) than on cats (n = 32), and only 9 studies focused exclusively on cats, our meta-analysis showed no difference in the global prevalence of ESBL-E. coli between dogs (6.87% [95% CI: 4.46-10.45%]) and cats (5.04% [95% CI: 2.42-10.22%]). A considerable diversity of ESBL genes (n = 60) and sequence types (ST) (n = 171) were recovered from companion animals. ESBL-E. coli encoded by CTX-M-15 (67.5%, 77/114) and SHV-12 (21.9%, 25/114), along with resistant strains of ST38 (22.7%, 15/66) and ST131 (50%, 33/66) were widespread and detected in all continents. While presence of ESBL-E. coli is widespread, the drivers influencing the observed ESBL-E. coli prevalence and the clinical relevance in veterinary medicine and public health along with economic impact of ESBL-E. coli infections among companion animals need to be further investigated.

Antimicrobial Resistance Genes and Diversity of Clones among ESBL- and Acquired AmpC-Producing Escherichia coli Isolated from Fecal Samples of Healthy and Sick Cats in Portugal

The aim of the study was to analyze the mechanisms of resistance in extended-spectrum beta-lactamase (ESBL)- and acquired AmpC (qAmpC)-producing Escherichia coli isolates from healthy and sick cats in Portugal. A total of 141 rectal swabs recovered from 98 sick and 43 healthy cats were processed for cefotaxime-resistant (CTX^R) E. coli recovery (in MacConkey agar supplemented with 2 µg/mL cefotaxime). The matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) method was used for E. coli identification and antimicrobial susceptibility was performed by a disk diffusion test. The presence of resistance/virulence genes was tested by PCR sequencing. The phylogenetic typing and multilocus sequence typing (MLST) were determined by specific PCR sequencing. CTX^RE. coli isolates were detected in seven sick and six healthy cats (7.1% and 13.9%, respectively). Based on the synergy tests, 11 of 13 CTX^RE. coli isolates (one/sample) were ESBL-producers (ESBL total rate: 7.8%) carrying the following ESBL genes: bla_CTX-M-1 (n = 3), bla_CTX-M-15 (n = 3), bla_CTX-M-55 (n = 2), bla_CTX-M-27 (n = 2) and bla_CTX-M-9 (n = 1). Six different sequence types were identified among ESBL-producers (sequence type/associated ESBLs): ST847/CTX-M-9, CTX-M-27, CTX-M-1; ST10/CTX-M-15, CTX-M-27; ST6448/CTX-M-15, CTX-M-55; ST429/CTX-M-15; ST101/CTX-M-1 and ST40/CTX-M-1. Three of the CTX^R isolates were CMY-2-producers (qAmpC rate: 2.1%); two of them were ESBL-positive and one ESBL-negative. These isolates were typed as ST429 and ST6448 and were obtained in healthy or sick cats. The phylogenetic groups A/B1/D/clade 1 were detected among ESBL- and qAmpC-producing isolates. Cats are carriers of qAmpC (CMY-2)- and ESBL-producing E. coli isolates (mostly of variants of CTX-M group 1) of diverse clonal lineages, which might represent a public health problem due to the proximity of cats with humans regarding a One Health perspective.

Molecular diversity of Extended-spectrum β-lactamase-producing Escherichia coli from vultures in Canary Islands

Antimicrobial resistance among isolates from wild animals is increasingly reported. Extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae, and particularly Escherichia coli, have spread worldwide as one of the most common multidrug-resistant organisms. The aim of this study was to determine the carriage rate of ESBL-producing E. coli isolates and their genetic characteristics in wild vultures from the Canary Islands. Faecal samples were collected from 22 apparently healthy free-ranging (wild) vulture chicks from Lanzarote and Fuerteventura (Canary Islands) during July 2019. They were seeded in MacConkey agar supplemented with cefotaxime (2 μg ml^-1 ). Colonies with typical morphology of E. coli were identified by MALDI-TOF-MS. Antimicrobial susceptibility was done by disk diffusion. Phenotypic detection of ESBL was performed by double-disk tests. The presence of bla_CTX-M , bla_SHV , bla_TEM , bla_KPC and bla_OXA-48 genes, as well as mcr-1 (colistin resistance), tetA/tetB and int1 gene, was tested by PCR/sequencing. Phylogenetic groups and multilocus sequence typing (MLST) were determined by PCR/sequencing. ESBL-producing E. coli isolates were detected in 5/22 tested animals (22.7%), and all isolates (one/animal) carried bla_CTX-M genes: bla_CTX-M-15 (n = 3) and bla_CTX-M-55 (n = 2). ESBL-positive isolates were ascribed to phylogenetic group D (two isolates), B₁ (two isolates) and A (one isolate), and five sequence types were detected (ST/phylogenetic-group/ESBL): ST515/B1/CTX-M-15, ST1290/A/CTX-M-15, ST38/D/CTX-M-15, ST457/D/CTX-M-55 and ST6448/B₁ /CTX-M-55; this suggests a genetic diversity among these isolates. Three CTX-M-15-producing isolates contained the bla_TEM gene and one the tetA gene. To our knowledge, this appears to be the first report of ESBL-producing E. coli in vulture chicks from the Canary Islands.

Pharmacokinetics of levofloxacin in non-lactating goats and evaluation of drug effects on resistance in coliform rectal flora

This study aimed to evaluate the pharmacokinetics/pharmacodynamics (PK/PD) of levofloxacin in non-lactating goats. Using a randomized cross-over study design, each group of animals (n = 7) received 2 mg/kg of levofloxacin intravenously (IV) and subcutaneously (SC). Plasma concentrations of levofloxacin were quantified by High Performance Liquid Chromatography with fluorescence detector (HPLC-FL). Rectal swabs were collected prior and after the treatment to identify the main bacterial population and to evaluate in vitro antimicrobial susceptibility using minimal inhibitory concentration (MIC) method. Mean values of terminal half-life for IV and SC groups were 4.56 and 5.14 h, respectively. After SC administration, the peak plasma concentration was achieved at 2 h, with a C_max of 3681 ng/mL. Mean bioavailability was 92.12%. Bacteria isolation showed the presence of Escherichia coli (E. coli) that quickly becomes resistant to levofloxacin potentially rendering the drug ineffective. Results seem to suggest that levofloxacin is able to reach considerable plasma concentrations after both IV and SC administration, but it must be considered that both routes of administration can lead to a reversible selection of resistance in gastro-intestinal bacteria.

Distribution and antimicrobial resistance profiles of bacterial species in stray cats, hospital-admitted cats, and veterinary staff in South Korea

BACKGROUND

Antimicrobial resistance is becoming increasingly important in both human and veterinary medicine. According to the One Health concept, an important step is to monitor the resistance patterns of pathogenic bacteria. In this study, the antimicrobial susceptibility patterns and trends of bacteria isolated from stray cats, hospital-admitted cats, and veterinary staff in South Korea between 2017 and 2018 were investigated.

RESULTS

The minimum inhibitory concentrations of different antibiotics for Staphylococcus spp., Enterobacteriaceae, and Enterococcus spp. were determined to establish representatives of different antibiotic classes relevant for treatment or surveillance. For Coagulase-positive and Coagulase-negative Staphylococci, resistance to fluoroquinolones was below 13%, but resistance to ampicillin and penicillin was high (20-88%). A total of 9.5, 12.1, and 40.3% of staphylococcal isolates from stray cats, hospital-admitted cats, and veterinary staff, respectively, were confirmed to be mecA positive. For Enterobacteriaceae, resistance to carbapenems, fluoroquinolones, and 3rd generation cephalosporins was low (0-11.1%). The Enterococcus spp. isolates showed no resistance to vancomycin. The antimicrobial resistance rates of the Staphylococcus spp. and Enterobacteriaceae isolates from stray cats were usually lower than those of isolates from hospital-admitted cats and veterinary staff, but the Enterococcus spp. isolates revealed the opposite. Thus, the antimicrobial resistance varied across bacterial species according to the source from which they were isolated.

CONCLUSIONS

Resistance to critically important compounds were low. However, the presence of antimicrobial resistance in cat isolates is of both public health and animal health concern.

Antimicrobial Prescribing Practices in Small Animal Emergency and Critical Care

Background: Antimicrobial use contributes to emergence of antimicrobial resistance. It was hypothesized that antimicrobial prescribing behavior varies between the emergency (ER) and critical care (CC) services in a veterinary teaching hospital. This study aimed to: (i) describe antimicrobial prescribing patterns in the ER and CC services; (ii) assess adherence to stewardship principles; (iii) evaluate the prevalence of multidrug resistant (MDR) bacterial isolates. Methods: Institution electronic medical records were queried for all antimicrobial prescriptions from the ER and CC services between 1/1/2017 and 12/31/2017. Prescriptions were manually reviewed, and the following data recorded: drug, dosage, duration, diagnosis, outcome, hospitalization duration, culture submission, and susceptibility results. Results: There were 5,091 ER visits, of which 3,125 were not transferred to another service. Of these emergency visits, 516 (16.5%) resulted in 613 antimicrobial drug prescriptions. The most commonly prescribed drugs for the ER were amoxicillin/clavulanate (n = 243, 39.6%), metronidazole (n = 146, 23.8%), and ampicillin/sulbactam (n = 55, 9.0%). The most common reasons for antimicrobial prescriptions were skin disease (n = 227, 37.0%), gastrointestinal disease (n = 173, 28.2%), and respiratory disease (n = 50, 8.2%). For ER patients 18 cultures were submitted, equivalent to a 3.5% submission rate. The CC service managed 311 case visits for 822 patient days. Of these, 133 case visits (42.7%) resulted in 340 prescriptions. The most commonly prescribed drugs for the CC service were ampicillin/sulbactam (n = 103, 30.3%), enrofloxacin (n = 75, 22.1%), and metronidazole (n = 59, 17.4%). The most common reasons for antimicrobial prescriptions were gastrointestinal disease (n = 106, 31.2%), respiratory disease (n = 71, 20.9%), and sepsis (n = 61, 17.9%). On the CC service, 46 patients had ≥1 culture submitted, equivalent to a 34.6% submission rate. Of patients prescribed antimicrobials, 13/38 (34%) with urinary tract disease, 2/28 (7%) with pneumonia, 1/11 (9%) with canine infectious respiratory disease complex and 2/8 (25%) with feline upper respiratory infection were compliant with published guidelines. Conclusions: Antimicrobial prescription was common in both ER and CC services and followed similar patterns. Adherence to published guidelines for urinary and respiratory infections was poor.

Whole-genome sequences of multidrug-resistant Escherichia coli in South-Kivu Province, Democratic Republic of Congo: characterization of phylogenomic changes, virulence and resistance genes

Background

Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli are responsible for severe infections worldwide. Whereas their genotypic and pathogenic characteristics are not documented in Democratic Republic of Congo (DRC), recent studies conducted at the Bukavu General Hospital in the South Kivu province highlighted their high prevalence in extra-intestinal infections. Here we provide data on molecular characterization of ESBL producing-Escherichia coli isolates from patients with extra-intestinal infections at this provincial hospital.

Methods

Whole-genome sequencing was carried out on 21 of these ESBL-producing Extra-intestinal Pathogenic Escherichia coli (ExPEC) for analysis of phylogenomic evolution, virulence factor and antimicrobial resistance (AMR) genes. Data were compared to phylogenetically close genomes using Multi-Locus Sequence Typing and Single Nucleotide Polymorphism-based phylogenetic approaches.

Results

The distribution of E. coli sequence types (ST) was as follows: ST 131 (n = 7), ST405 (n = 4), ST410 (n = 2), and other STs (ST10, ST58, ST95, ST393, ST443, S617, ST648, and ST2450). All ST131 belonged to the O25b-ST131 pandemic clone. Unexpectedly, they harbored more virulence genes than their GenBank counterparts. IncF plasmid replicons included novel FIB 69, FII 105 and FII 107 alleles. ESBL-genes included the plasmid-mediated CTX-M-15 in all isolates, and the SHV-12 allele. Other AMR genes included blaOXA-1, blaTEM-1, as well as genes encoding resistance against aminoglycosides, quinolones, chloramphenicol, rifampicin, tetracyclines, sulfonamides and trimethoprim.

Conclusion

Current data confirm the clonal spread of ESBL-producing ST131 and ST405 clones in patients from South Kivu, and the acquisition of resistance and virulence genes. A closer survey of AMR and virulence should therefore be prompted in this high-risk area.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-3763-3) contains supplementary material, which is available to authorized users.

Antimicrobial use practices of veterinary clinicians at a veterinary teaching hospital in the United States

Indiscriminate antimicrobial use (AMU) is a factor contributing to antimicrobial resistance (AMR). The objectives of this study were to (1) identify factors influencing AMU practices of veterinary clinicians at The University of Tennessee Veterinary Medical Center (UTVMC), (2) analyze the clinicians' preferential choices of antimicrobials, and (3) evaluate their perceptions, opinions, and concerns regarding AMU and AMR. A total of 121 clinicians were surveyed. Among the 62 respondents, culture and susceptibility test results and pressure from clients were the most and least important factors in their antimicrobial prescription decision-making, respectively. Compared to clinicians who obtained their veterinary degree from 1970 to 1999, those who graduated from 2000 to 2009 and 2010-2016 were 3.96 (P = 0.034) and 5.39 (P = 0.01) times less concerned about AMR, respectively. There is a critical need to increase awareness about judicious AMU practices among clinicians, increase emphasis about AMR in the present veterinary curriculum, and implement antimicrobial stewardship program (AMS) in this institution. Educational activities in combination with awareness campaigns and the stewardship programs could be used to improve AMU practices at this hospital. More client education on AMR is needed.

Brazil's resolutions to regulate the sale of antibiotics: Impact on consumption and Escherichia coli resistance rates

OBJECTIVE

The aim of this study was to determine the impact of two resolutions to restrict antibiotic use (RDCs no. 44/2010 and 20/2011) in the Campinas metropolitan area (Sao Paulo, Brazil) on antibiotic consumption, resistance rates, and trends in Escherichia coli-causing community-acquired urinary tract infection (UTI).

METHODS

The annual retail sale information of antibiotics from drugstores in the Campinas metropolitan area between 2008 and 2012 were obtained through the Intercontinental Medical Statistics Health of Brazil. The daily-defined dose (DDD)/1000 inhabitants/day was calculated from these data to measure consumption. To examine resistance rates, we performed an observational retrospective study in a Campinas teaching hospital, where urinary cultures from outpatients with a clinical suspicion of UTI between October 2009 and September 2015 were analyzed.

RESULTS

We observed an increase in rates of antibiotic sales from 2008 to 2011 (cephalosporin: 216.8%, quinolones: 170.9%, aminopenicillins: 140.9%), followed by a decrease in sales in 2012 (cephalosporin: 19.4%, quinolones: 12.7%, aminopenicillins: 11.1%). Sale of nitrofurans, however, did not significantly change during this period. In the retrospective analysis, we observed a significant increasing trend of E. coli resistance for all antibiotic classes, except nitrofurans and folate pathway inhibitors.

CONCLUSIONS

We found changes in antibiotic consumption, with an initial increase, followed by a decrease in sales after implementation of the resolutions. However, bacterial resistance does not appear to be affected by the RDCs.