Genomic features of a highly virulent, ceftiofur-resistant, CTX-M-8-producing Escherichia coli ST224 causing fatal infection in a domestic cat.

OBJECTIVES: Escherichia coli strains producing extended-spectrum ß-lactamases (ESBLs), especially CTX-M-type, have been largely described in companion animals; however, genomic data are lacking to clarify the clinical impact of ESBL-producing isolates in these hosts. The aim of this study was to present the genomic features of a highly virulent, ceftiofur-resistant, CTX-M-8-producing E. coli isolate from a case of pneumonia in a domestic cat with fatal outcome. METHODS: Genomic DNA was sequenced using an Illumina NextSeq 500 platform and was assembled using CLC Genomic Workbench. Genomic data were analysed using online bioinformatics tools. RESULTS: The genome size was evaluated at 5.1Mb, with 5334 protein-coding sequences. The strain was assigned to sequence type 224 (ST224) and presented genes conferring resistance to ß-lactams (blaCTX-M-8), sulphonamides (sul2), tetracycline (tetA) and trimethoprim (dfrA14) as well as chromosomal point mutations in ParC (S80I), GyrA (S83L) and GyrB (D87N). In addition, the presence of the virulence genes cba, gad, ipfA, iroN, iss, mchF and tsh was detected. CONCLUSION: This draft genome sequence might provide important data for a better understanding of genomic aspects regarding the dissemination of CTX-M-8-producing E. coli in the human-animal-environment interface.

Multidrug-resistant CTX-M-15-producing Klebsiella pneumoniae ST231 associated with infection and persistent colonization of dog.

Extended spectrum ß-lactamase (ESBL)-producing bacterial infections in veterinary medicine are a clinical and epidemiological challenge. We report a case of CTX-M-15-producing Klebsiella pneumoniae infection followed by persistent colonization, in a dog presenting with bilateral purulent nasal discharge and dyspnea. In this regard, 5 broad-spectrum cephalosporin-resistant K. pneumoniae isolates were recovered from infection and surveillance cultures, collected during 1 year and eight months study. Genomic analysis of a representative clone of K. pneumoniae (KpPB76) revealed the presence of the human-associated lineage ST231, whereas resistome data confirmed the presence of genes conferring resistance to aminoglycosides, ß-lactams, fluoroquinolones, fosfomycin, phenicols, sulfonamides, tetracyclines and trimethoprim. In the absence of therapeutic options, meropenem therapy was used, contributing to the control of infection during persistent carriage of K. pneumoniae CTX-M-15/ST231. Persistent colonization of companion animals with ESBL-producing bacteria could be result from a variety of situations, including multi introduction from the owner or household family members to pets, or from environmental exposure; whereas colonized animals may serve as an important source for the spread of ESBL-producing strains in the human-animal interface.

Pythiosis of the digestive tract in sheep.

Cutaneous and rhinofacial infections by Pythium insidiosum have previously been reported in sheep in Brazil. In the current study, a new form of pythiosis involving the alimentary tract of 2 nursing lambs from 2 different farms in the semiarid region of Brazil is described. The first lamb showed food regurgitation, lethargy, and anorexia, and died 5 days after the presentation of clinical signs. The second lamb had no history of gastrointestinal disease before death. Necropsy findings were similar in both lambs. The mucosa of the esophagus, reticulum, rumen, omasum, and abomasum showed ulcerated areas covered by yellowish caseous granular exudate. The lesions were transmural and extended to the serosal surfaces, and adhesions were observed between the serosa of the forestomachs and abomasum to the liver and diaphragm. Histologic lesions consisted of pyogranulomatous necrotizing transmural esophagitis, rumenitis, reticulitis, omasitis, and abomasitis with vascular thrombosis and intralesional hyphae. Pythium insidiosum was confirmed as the etiology by immunohistochemistry and culture. The presence of sheep in the vicinity of water ponds during the hot, dry season when forage is not available in the pastures seems to be the main predisposing factor for the occurrence of pythiosis in sheep in the Brazilian semiarid region.

Protothecosis by Prototheca wickerhamii in goats.

This article reports a new case of protothecosis by Prototheca wickerhamii in goats. The animal presented severe respiratory difficulty and nodules, sometimes ulcerated, in the nasal vestibule, mucocutaneous junction of the nostrils and skin of the face. Prototheca wickerhamii was isolated from the lesions. The animal had no clinical or haematologiccl evidence of immunodepression. The agent was highly resistant to antimicrobial drugs. The goat was treated unsuccessfully with fluconazole and euthanised 10 months after the diagnosis of the disease. Histological lesions were necrotising pyogranulomatous dermatitis, rhinitis and osteomyelitis with myriads of walled sporangia characteristic of P. wickerhamii. It is suggested that in goats, protothecosis is characterised by a chronic, slowly progressive infection, which affects immunologically competent goats, causing multifocal, ulcerative, pyogranulomatous and necrotising lesions of the mucosa of the nasal vestibule, mucocutaneous junctions of the nostrils and skin of the face.