Genetic diversity, virulence genotype and antimicrobial resistance of uropathogenic Escherichia coli (UPEC) isolated from sows.

BACKGROUND: Urinary tract infections (UTI) cause severe losses to the swine industry worldwide and uropathogenic Escherichia coli (UPEC) are the main agent isolated from UTI in sows. OBJECTIVE: The aim of this study was to investigate the virulence genes, assess the phylogenetic background, clonal diversity, and the pattern of resistance to antimicrobials in 186 isolates of UPEC isolated from sows in Brazil. MATERIALS AND METHODS: Urine samples from 300 sows of three herds with clinical signs from São Paulo State (Brazil) were screened for UTI; samples with suggestive results were submitted to bacterial isolation. E. coli strains isolated were characterized using disk diffusion technique, polymerase chain reaction and Single-enzyme amplification fragment length polymorphism (SE-AFLP). RESULTS: Virulence genes focH and papC were present in 78.5% and 58% of strains, respectively, followed by cnf1 (23.2%), afa (13.4%), sfa (11.3%), iucD (6.9%), and hlyA (1.6%). No clonal relatedness was found by SE-AFLP. A total of 98% of isolates (182/186) were multidrug resistant, and the highest levels of resistance were to sulfonamides, tetracycline, florfenicol, and ampicillin. Isolates were classified in phylogenetic group B1 (34.4%), followed by D (33.9%), E (30.1%) and A (1.6%). CONCLUSIONS: The data obtained suggest that pigs from clinically affected herds may serve as a reservoir of uropathogenic and multidrug-resistant E. coli strains.

Identification through MALDI-TOF mass spectrometry and antimicrobial susceptibility profiling of bacterial pathogens isolated from sow urinary tract infection.

BACKGROUND: Urinary tract infection (UTI) is a common disease in sows due to intensification of pig production. Despite direct economic losses, UTI prevalence and respective microbial identification are still poorly studied. OBJECTIVE: The aims of this study were to identify the causative agents of UTI in sows through MALDI-TOF MS and to characterize their antimicrobial resistance profiles. MATERIALS AND METHODS: Urine samples from 300 sows of three herds from São Paulo State (Brazil) were screened for UTI; suggestive samples were submitted to bacterial isolation. Species identification was performed by MALDI-TOF MS and susceptibility profiles were determined using disc diffusion method. RESULTS: 128 samples suggestive of UTI were analyzed; 48% of the animals presented UTI caused by a single pathogen, while the remaining 52% presented mixed infection. Escherichia coli stood out with the highest frequency among both single and mixed infections. The Gram-positive were exclusively associated with 27% of single infections. The mixed infections were further classified into 49 profiles. The high frequency of multiresistant profiles stood out for most of the studied isolates. CONCLUSIONS: MALDI-TOF MS enabled the identification of rare pathogens related to UTI which may represent higher risk for porcine health, especially considering high frequency of multiresistant profiles.

Molecular and antimicrobial susceptibility characterization of Globicatella sulfidifaciens isolated from sow's urinary tract infection.

BACKGROUND: The Globicatella genus comprises Gram-positive, facultative anaerobic, α-hemolytic and catalase negative cocci morphologically and phenotypically very similar to Streptococcus and Aerococcus genus which can lead to misidentification and underestimation of this pathogen. Globicatella species have already been isolated from human and animals with heart and brain disorders. Their clinical relevance in animals, and its zoonotic potential, remains unknown due to the difficulty in their identification. OBJECTIVE: To present the isolation, phenotypic and molecular characterization of G. sulfidifaciens from urinary tract infection in sows. MATERIALS AND METHODS: Urine samples from 140 sows of two swine herds located in São Paulo State (Brazil) yielded the isolation of three presumptive G. sulfidifaciens strains. Identification and species confirmation were done by MALDI-TOF MS and 16S rRNA sequencing. Strains were further characterized by single enzyme amplified fragments length polymorphism (SE-AFLP) and broth microdilution techniques. RESULTS: All three isolates were confirmed as G. sulfidifaciens. The SE-AFLP genotyping resulted in distinct fingerprint patterns for each strain. All isolates presented high MIC values to tetracycline, sulphonamides, aminoglycosides and tylosin tartrate, which present high usage in human and animal medicine. CONCLUSIONS: Globicatella sulfidifaciens could be related to sporadic urinary tract infections in swine and appear to present alarming antimicrobial susceptibility profile. It is necessary to differentiate Streptococcus-like microorganisms in routine laboratory diagnostics for the correct identification of underestimated species potentially pathogenic to animals.