CTX-M-15-producing Klebsiella pneumoniae ST273 associated with nasal infection in a domestic cat.

OBJECTIVES: The aim of this study was to investigate the genetic context of expanded-spectrum ß-lactam resistance in a Klebsiella pneumoniae strain causing a hard-to-treat nasal infection in a domestic cat. METHODS: A K. pneumoniae isolate was recovered from a 4-year-old male cat hospitalised in a veterinary hospital in Paraíba, Northeastern Brazil. Following phenotypic confirmation of multidrug resistance by the disk diffusion method, the genome was sequenced using an Illumina MiSeq system. Multilocus sequence typing (MLST) and structural features related to antimicrobial resistance were determined by downstream bioinformatics analyses. RESULTS: The strain was confirmed as sequence type 273 (ST273) K. pneumoniae harbouring a variety of genes conferring antimicrobial resistance to phenicols tetracyclines, aminoglycosides, ß-lactams, fosfomycin, sulfonamides and quinolones. Two plasmids were identified. Plasmid p114PB_I co-harboured a set of plasmid-borne resistance genes [blaCTX-M-15, blaTEM-1, qnrS1, tetD, tetR, sul2, aph(6)-Id, aph(3'') and cat2]. Notably, the multiresistance region was characterised as a chimeric plasmid structure sharing high sequence homology with several plasmids from Enterobacteriaceae. The second plasmid (p114PB_II) was characterised as a plasmid present in many genomes belonging to K. pneumoniae. CONCLUSION: The genetic context of the plasmid sequences harboured by a veterinary pathogenic K. pneumoniae isolate reveals the high complexity of horizontal gene transfer mechanisms in the acquisition of antimicrobial resistance genes. The emergence, dissemination and evolution of antimicrobial resistance must be investigated from a One Health perspective.

First report of a livestock-associated methicillin-resistant Staphylococcus aureus ST126 harbouring the mecC variant in Brazil.

Staphylococcus aureus is a versatile and highly adaptable pathogen associated with a wide range of infectious diseases in humans and animals. In the last decades, concern has increased worldwide due to the emergence and spread of methicillin-resistant S. aureus (MRSA) strains shortly after this drug became a therapeutic option. In this study, we report the genomic features of the first mecC-mediated, ß-lactam resistant MRSA strain associated with livestock in Brazil and in the American continent. Three clonally related phenotypic MRSA isolates originated from a dairy herd were confirmed by polymerase chain reaction as mecC-harbouring MRSA isolates. Whole-genome sequencing was performed by Illumina Miseq platform. Downstream analyses showed that the strain was identified as the sequence type 126 (ST126) and spa type t605. In silico analysis revealed a mecC homolog gene in the orfX region associated with different penicillin-binding proteins. Moreover, genes encoding for efflux pump systems (arlR, mepR, LmrS, norA and mgrA), and antibiotic inactivation enzymes (blaZ and FosB) were also detected. Virulence analyses revealed that the strain harbours genes encoding for exoenzymes (aur, splA, splB and splE), toxin (hlgA, hlgB, hlgC, lukD and lukE) and enterotoxin (sea). The epidemiologic and genomic information provided by this study will support further epidemiological and evolutionary investigations to understand the origin and dissemination of mecC-MRSA among animals and its impact on public health.

Genetic traceability of Staphylococcus aureus strains isolated from primiparous dairy cows mastitis, humans and environment in the Northeast region of Brazil / Rastreabilidade genética de cepas de Staphylococcus aureus isoladas de mastite de vacas primíparas, ordenhadores e ambiente de ordenha na região Nordeste do Brasil

ABSTRACT: This research aimed to investigate the genotypic relatedness of 18 Staphylococcus aureus strains isolated from intramammary infections in primiparous cows and extramammary sites on five dairy herds by rep-PCR using RW3A primers, and by PFGE using the endonuclease SmaI. The isolates were also evaluated in vitro for the susceptibility against beta-lactam antimicrobials drugs (penicillin and oxacillin), considering that beta-lactams are frequently used for treating staphylococcal intrammamary infections. The rep-PCR typing was highly discriminatory (D value= 0.9804) and a total of 15 patterns were detected. The PFGE method was also highly discriminatory (D value= 0.9667) and a total of 13 patterns were observed. A total of 15 out of 18 (83%) isolates were resistant to penicillin and one out of 18 (6%) to oxacillin. In conclusion, these findings confirmed the occurrence of a high genetic diversity of S. aureus strains at the herds and the presence of clonally-related strains only at the same herd, emphasizing a variety of genotypic profiles among the isolates.

RESUMO: Objetivou-se com este estudo investigar a correlação genética de 18 cepas de Staphylococcus aureus isoladas de infecções intramamárias em vacas primíparas e de locais extramamários em cinco propriedades leiteiras através das técnicas de PCR por sequências palindrômicas extragênicas repetitivas (rep-PCR), usando iniciadores RW3A, e de eletroforese em gel de campo pulsado (PFGE), usando a endonuclease SmaI. Os isolados também foram avaliados in vitro quanto à suscetibilidade aos antimicrobianos beta-lactâmicos (penicilina e oxacilina). A tipagem por rep-PCR foi altamente discriminatória (valor D = 0,9804) e um total de 15 padrões foram detectados. Os isolados de S. aureus foram agrupados em três grupos diferentes (A a C), com 80% de similaridade. A técnica de PFGE também foi altamente discriminatória (valor D = 0,9667) e um total de 13 padrões foi observado. A análise do dendrograma com um coeficiente de similaridade de 80% gerou dois grupos diferentes (A e B). Além disso, cepas clonais isoladas do leite foram identificadas na mesma propriedade pelos dois métodos de tipificação e, apesar da presença de cepas dominantes, nossos resultados sugerem uma alta diversidade genética dentre as cepas de S. aureus analisadas. Um total de 15, dos 18 (83%) isolados, eram resistentes à penicilina e um dos 18 (6%) à oxacilina. Assim, esses achados confirmam a ocorrência de uma alta diversidade genética de cepas de S. aureus nas propriedades e a presença de cepas clonalmente relacionadas apenas na mesma propriedade, enfatizando uma variedade de perfis genotípicos entre os isolados.

Occurrence of KPC-Producing Escherichia coli in Psittaciformes Rescued from Trafficking in Paraíba, Brazil.

The emergence and spread of antimicrobial resistance pose a threat to public health globally. Antibiotic-resistant bacteria and genes can disseminate among environments, animals and humans. Therefore, investigation into potential reservoirs of multidrug-resistant bacteria is of great importance to the understanding of putative transmission routes of resistant bacteria and resistance genes. This study aimed to report the occurrence of Escherichia coli harboring the Klebsiella pneumoniae carbapenemase-producing gene (blaKPC) in Psittaciformes rescued from wildlife trafficking in Paraíba State, Brazil. Cloacal swabs were collected from thirty birds and cultured by conventional microbiology using MacConkey and serum tryptone glucose glycerol (STGG) media supplemented with selective antimicrobials. E. coli isolates (n = 43) were identified by phenotypic tests and confirmed by MALDI-TOF. Antimicrobial susceptibility profiles were determined by means of Kirby-Bauer test. All isolates were further screened for extended-spectrum beta-lactamase (ESBL) production, and putative genes encoding ESBL were investigated by PCR. Additionally, blaKPC-harboring strains were genotyped by REP-PCR. A total of 43 E. coli phenotypically resistant isolates were recovered. The highest resistance rate was observed against ciprofloxacin. Among the resistance genes, only blaKPC was found in seven different birds from three species. According to the genotyping, these seven isolates belonged to four different strains. To date, this is the first report on the occurrence of KPC-E. coli in Psittaciformes rescued from trafficking in Northeastern Brazil. Due to the high clinical importance of KPC-E. coli, our findings suggest that wild animals in captivity at wildlife rescue centers can play a role as reservoirs of bacteria that are resistance to Critically Important antimicrobials in human medicine.