Canine bacterial urinary tract infections: new developments in old pathogens

Pathogenic profile and antimicrobial resistance of Escherichia coli, Escherichia marmotae and Escherichia ruysiae detected from hunted wild boars in Sardinia (Italy)

The objective of this study was to evaluate the occurrence of E. coli in hunted wild boars in Sardinia (Italy) and to further characterize the isolates with Whole Genome Sequencing to assess the genetic relatedness and the presence of virulence and antimicrobial resistance (AMR) genes. Samples were taken from 66 wild boars between 2020 and 2022 slaughtered in five hunting houses. A total of 181 samples were tested, including 66 samples from mesenteric lymph nodes, 66 samples from colon content and 49 samples from carcass surface. Isolates referable to Escherichia species were detected in all of the wild boars sampled. On a selection of 61 isolates, sequencing was conducted and antimicrobial susceptibility was tested. Among these, three isolates were confirmed to be two Escherichia marmotae (cryptic clade V) and one Escherichia ruysiae (cryptic clade III). E. coli pathotypes identified were UPEC (13 %), ExPEC-UPEC (5.6 %) and ETEC (3.7 %). Moreover, 3/6 E. marmotae isolates had typical ExPEC genes. Genetic similarity was observed in isolates collected from animals slaughtered in the same hunting house; this suggests epidemiological links deriving from the presence of animals infected with closely related strains or the result of cross-contamination. Antimicrobial resistance genes were detected in three non-pathogenic E. coli isolates: one isolate had sul2, tet(B), aph(6)-ld and aph(3″)-lb resistance genes and two had the fosA7 gene. This study confirmed that wild boars can act as reservoirs and spreaders of pathogenic Escherichia species and it provides information for future comparative genomic analysis in wildlife. Although isolates showed a limited resistome, the detection of resistance in non-pathogenic isolates underlines the need to monitor antimicrobial resistance in the wild boar population. To the best of our knowledge, this is the first detection of E. mamotae and E. ruysiae isolates in wild boars in Italy and the presence of this pathogen in wildlife and livestock need to be investigated further.

Distribution of papA and papG Variants among Escherichia coli Genotypes: Association with Major Extraintestinal Pathogenic Lineages

The pyelonephritis-associated fimbria (P fimbria) is one of the most recognized adhesion determinants of extraintestinal pathogenic Escherichia coli strains (ExPECs). Twelve variants have been described for the gene encoding the P fimbria major structural subunit PapA and three variants for the gene encoding the adhesin subunit PapG. However, their distribution among the ExPEC diversity has not been comprehensively addressed. A complete landscape of that distribution might be valuable for delineating basic studies about the pathogenicity mechanisms of ExPECs and following up on the evolution of ExPEC lineages, particularly those most epidemiologically relevant. Therefore, we performed a massive descriptive study to detect the papA and papG variants along different E. coli genotypes represented by genomic sequences contained in the NCBI Assembly Refseq database. The most common papA variants were F11, F10, F48, F16, F12, and F7-2, which were found in significant association with the most relevant ExPEC genotypes, the phylogroups B2 and D, and the sequence types ST95, ST131, ST127, ST69, ST12, and ST73. On the other hand, the papGII variant was by far the most common followed by papGIII, and both were also found to have a significant association with common ExPEC genotypes. We noticed the presence of genomes, mainly belonging to the sequence type ST12, harboring two or three papA variants and two papG variants. Furthermore, the most common papA and papG variants were also detected in records representing strains isolated from humans and animals such as poultry, bovine, and dogs, supporting previous hypotheses of potential cross-transmission. Finally, we characterized a set of 17 genomes from Chilean uropathogenic E. coli strains and found that ST12 and ST73 were the predominant sequence types. Variants F7-1, F7-2, F8, F9, F11, F13, F14, F16, and F48 were detected for papA, and papGII and papGIII variants were detected for papG. Significant associations with the sequence types observed in the analysis of genomes contained in the NCBI Assembly Refseq database were also found in this collection in 16 of 19 cases for papA variants and 7 of 9 cases for the papG variants. This comprehensive characterization might support future basic studies about P fimbria-mediated ExPEC adherence and future typing or epidemiological studies to monitor the evolution of ExPECs producing P fimbria.

Biofilm-forming ability, antibiotic resistance and phylogeny of Escherichia coli isolated from extra intestinal infections of humans, dogs, and chickens

Escherichia coli (E. coli) causes various infections in humans and animals. The biofilm-forming ability of E. coli has increased antimicrobial resistance and capacity to cause recurrent and chronic infections. This study determined the biofilm-forming ability of E. coli isolated from extraintestinal infections of humans, chickens, and dogs in relation to the phylogroup, type of infection, and antibiotic resistance. Isolates from chickens showed significantly higher biofilm-forming ability compared to those causing urinary tract infections in humans (p = 0.0001). Further, isolates belonging to phylogroup B1 displayed a higher likelihood to form biofilms. Resistance to ciprofloxacin and trimethoprim-sulfamethoxazole was positively correlated with biofilm-forming ability. Harbouring plasmid-mediated quinolone resistance gene, qnrS was also positively correlated with biofilm formation. This study provides insight into factors such as phylogroup and the type of infections that could enhance biofilm formation, as well as genotypic and phenotypic antibiotic resistance that could correlate with the ability to form biofilms.

Genotypic Characterization of Uropathogenic Escherichia coli from Companion Animals: Predominance of ST372 in Dogs and Human-Related ST73 in Cats

Extraintestinal pathogenic Escherichia coli (ExPEC) account for over 80% and 60% of bacterial urinary tract infections (UTIs) in humans and animals, respectively. As shared uropathogenic E. coli (UPEC) strains have been previously reported among humans and pets, our study aimed to characterize E. coli lineages among UTI isolates from dogs and cats and to assess their overlaps with human UPEC lineages. We analysed 315 non-duplicate E. coli isolates from the UT of dogs (198) and cats (117) collected in central Germany in 2019 and 2020 utilizing whole genome sequencing and in silico methods. Phylogroup B2 (77.8%), dog-associated sequence type (ST) 372 (18.1%), and human-associated ST73 (16.6%), were predominant. Other STs included ST12 (8.6%), ST141 (5.1%), ST127 (4.8%), and ST131 (3.5%). Among these, 58.4% were assigned to the ExPEC group and 51.1% to the UPEC group based on their virulence associated gene (VAG) profile (ExPEC, presence of ≥VAGs: papAH and/or papC, sfa/focG, afaD/draBC, kpsMTII, and iutA; UPEC, additionally cnf1 or hlyD). Extended-spectrum cephalosporin (ESC) resistance mediated by extended-spectrum β-lactamases (ESBL) and AmpC-β-lactamase was identified in 1.9% of the isolates, along with one carbapenemase-producing isolate and one isolate carrying a mcr gene. Low occurrence of ESC-resistant or multidrug-resistant (MDR) isolates (2.9%) in the two most frequently detected STs implies that E. coli isolated from UTIs of companion animals are to a lesser extent associated with resistance, but possess virulence-associated genes enabling efficient UT colonization and carriage. Detection of human-related pandemic lineages suggests interspecies transmission and underscores the importance of monitoring companion animals.

Previous Antibiotic Exposure Reshapes the Population Structure of Infecting Uropathogenic Escherichia coli Strains by Selecting for Antibiotic Resistance over Urovirulence

Antibiotic therapy is the standard of care for urinary tract infections (UTIs) caused by uropathogenic Escherichia coli (UPEC). However, previous antibiotic therapy may impart a selective pressure that influences the population structure and pathogenic potential of infecting UPEC strains. Here, we conducted a 3-year study using whole-genome-sequencing analysis and retrospective medical record review to characterize how antibiotic exposure influenced the phenotypic antibiotic resistance, acquired resistome, virulome, and population structure of 88 UTI-causing E. coli strains from dogs. A majority of UTI-associated E. coli strains were from phylogroup B2 and clustered within sequence type 372. Previous antibiotic exposure was associated with a population shift toward UPEC from phylogroups other than the typical urovirulent phylogroup B2. The specific virulence profiles within the accessory virulome that were associated with antibiotic use were elicited by the effect of antibiotics on UPEC phylogenetic structure. Among phylogroup B2, antibiotic exposure increased the quantity of genes within the resistome and the odds of developing reduced susceptibility to at least one antibiotic. Non-B2 UPEC strains harbored a more diverse and greater resistome that conferred reduced susceptibility to multiple antibiotic classes following antibiotic exposure. Collectively, these data suggest that previous antibiotic exposure establishes an environment that provides a selective edge to non-B2 UPEC strains through their diverse and abundant antibiotic resistance genes, despite their lack of urovirulence genes. Our findings highlight the necessity for judicious use of antibiotics as we uncover another mechanism by which antibiotic exposure and resistance can influence the dynamics of bacterial infectious disease. IMPORTANCE Urinary tract infections (UTIs) are one of the most common infections of dogs and humans. While antibiotic therapy is the standard of care for UTIs and other infections, antibiotic exposure may influence the pathogenic profile of subsequent infections. We used whole-genome sequencing and retrospective medical record review to characterize the effect of systemic antibiotic therapy on the resistance, virulence, and population structure of 88 UTI-causing UPEC strains isolated from dogs. Our results indicate that antibiotic exposure alters the population structure of infecting UPEC strains, providing a selective edge for non-B2 phylogroups that harbor diverse and abundant resistance gene catalogues but fewer urovirulence genes. These findings highlight how antibiotic resistance can influence pathogen infection dynamics and have clinical implications for the judicious use of antibiotics for bacterial infections.

A Retrospective Clinico-Pathologic Study of 35 Dogs with Urethral Transitional Cell Carcinoma Undergoing Treatment

Chemotherapy and cyclooxygenase inhibitors (COXi) are primary treatments for canine urethral transitional cell carcinoma (uTCC), a tumor known for its aggressiveness and poor prognosis. This retrospective study aimed to evaluate the clinico-pathological characteristics, treatment modalities, and prognostic factors of 35 dogs with confirmed uTCC that received chemotherapy and COXi. Upon admission, urethral obstruction (UO) and urinary tract infection (UTI) were observed in seven (20%) dogs each. Gemcitabine (n = 20; 57.1%) and vinblastine (n = 10; 28.6%) were commonly used as first-line therapies, with four dogs also receiving radiation therapy. Based on RECIST, one (2.9%) dog achieved complete remission, nine (25.7%) partial remission, 20 (57.14%) showed stable disease, and five (14.3%) progressed. Among dogs with UO, six (85.7%) showed resolution or improvement after the first chemotherapy dose. The median time to local progression was 171 days (range: 107-235), and the median survival time was 333 days (range: 158-508). Dogs with UO upon admission had a higher risk of local progression, while both UO and UTI were associated with an increased risk of overall disease progression and tumor-related death. Additionally, gemcitabine significantly improved metastatic control. This study identified UO and UTI as negative prognostic factors, highlighting the importance of a multimodal approach in managing uTCC.

Escherichia coli-associated follicular cystitis in dogs: Clinical and pathologic characterization

BACKGROUND

Follicular cystitis is an uncommon inflammatory change in the urinary bladder wall characterized by the formation of tertiary lymphoid structures (TLSs) in the submucosa.

OBJECTIVES

To characterize clinical and pathologic features of follicular cystitis in dogs and to explore in situ distribution and possible role of Escherichia coli as an associated cause.

ANIMALS

Eight dogs diagnosed with follicular cystitis and 2 control dogs.

METHODS

Retrospective descriptive study. Dogs diagnosed with follicular cystitis (macroscopic follicular lesions in the urinary bladder mucosa and histopathologic detection of TLSs in bladder wall biopsies) were identified from medical records. Paraffin embedded bladder wall biopsies were subject to in situ hybridization for E. coli 16SrRNA identification.

RESULTS

Follicular cystitis was diagnosed in large breed (median weight 24.9 kg, interquartile range [IQR] 18.8-35.4 kg) female dogs with a history of chronic recurrent urinary tract infections (UTIs; median duration of clinical signs 7 months, IQR 3-17 months; median number of previous UTIs 5, IQR 4-6). Positive E. coli 16SrRNA signal was detected within developing, immature and mature TLSs in 7/8 dogs, through submucosal stroma in 8/8 dogs and within the urothelium in 3/8 dogs.

CONCLUSIONS AND CLINICAL IMPORTANCE

Chronic inflammation associated with an intramural E. coli infection in the urinary bladder wall represents a possible triggering factor for the development of follicular cystitis.

Adherence of uropathogenic Escherichia coli in dog urine after consumption of food supplemented with cranberry (Vaccinium macrocarpon)

Introduction

Escherichia coli is the most common pathogen isolated from the urine of dogs with urinary tract infections (UTIs). While there are many studies in humans investigating the potential for the prevention of UTIs by dietary consumption of cranberry, few analogous studies have been carried out in dogs.

Material and Methods

Eight dogs, four male and four female, were successively fed two diets, first a control without cranberry, and then the second diet containing cranberry extracts. Naturally excreted urine was collected on the tenth day after the start of each diet for 24 h and used for bacterial growth. Madin-Darby canine kidney cell adherence by the uropathogenic E. coli G1473 strain expressing type 1 pili and positive for P pili and haemolysin gene markers was quantified after growth in urine samples.

Results

Significant reductions in bacterial adherence to MDCK cells (from −16.5 to −73.4%, P < 0.05) were observed in the four females but not in the males after consumption of the cranberry extracts compared to the same animals consuming the control diet.

Conclusion

Dietary supplementation with cranberry may provide some degree of protection to female dogs against adhesion of uropathogenic E. coli to urinary epithelial cells.

Isolation of Oral Bacteria, Measurement of the C-Reactive Protein, and Blood Clinical Parameters in Dogs with Oral Tumor

Canine oral cancers have a poor prognosis and are related to chronic inflammation. This may pose a risk of secondary bacterial infection. This study aimed to compare the bacteria isolated from oral swab samples, values of C-reactive proteins (CRPs), and clinical blood profiles of dogs with and without oral mass. A total of 36 dogs were divided in three groups: no oral mass (n = 21), oral mass (n = 8), and metastasis groups (n = 7). Significantly, both the clinical groups (the oral mass group and metastasis group) showed anemia, a decrease in the albumin-to-globulin ratio (AGR), and an increase in the neutrophil-to-lymphocyte ratio (NLR), globulin-to-albumin ratio (GAR), CRP, and CRP-to-albumin ratio (CAR) compared to the normal group. CAR showed an increasing trend in the oral mass and metastasis groups (10 times and 100 times, respectively) compared to the no oral mass group (P < 0.001). Neisseria spp. (20.78%) was the main isolated bacteria in all groups. The main genera in the no oral mass group were Neisseria spp. (28.26%), Pasteurella spp. (19.57%), and Staphylococcus spp. (19.57%). Neisseria spp., Staphylococcus spp., Klebsiella spp., and Escherichia spp. were found equally (12.5%) in the oral mass group. Escherichia spp. (26.67%), Pseudomonas spp. (13.33%), and Staphylococcus spp. (13.33%) were the main genera in the metastasis group. Interestingly, Neisseria spp. decreased in the clinical groups (Fisher's exact = 6.39, P=0.048), and Escherichia spp. increased in the metastasis group (Fisher's exact = 14.00, P=0.002). The difference of oral bacteria in clinical dogs compared to healthy dogs may be related to microbiome alterations, and both the clinical groups showed the increment of inflammatory biomarkers. This suggested that further studies should be conducted on the correlation between the specific bacteria, CRP, blood clinical parameters, and type of canine oral mass.

Prevalence and Antimicrobial Resistance of Bacterial Uropathogens Isolated from Dogs and Cats

Bacterial urinary tract infection (UTI) is a common diagnosis in companion animal practice and is one of the leading reasons for antimicrobial prescriptions. We analysed 1862 samples from the urinary tract of dogs and cats, submitted to a veterinary microbiological diagnostic laboratory in 2019 and 2020 in Germany. Susceptibility of 962 uropathogenic isolates to 15 antimicrobials, suggested as first- and second-line treatment options for UTI, was determined according to CLSI recommendations. Bacterial growth of uropathogens was detected in 43.9% of dog and in 38.5% of cat samples. Escherichia (E.) coli was the most frequently isolated pathogen (48.4%), followed by Enterococcus spp. (11.9%) and coagulase-positive staphylococci (CoPS; 11.5%). Females were more likely to exhibit a positive microbiological culture. Regarding first-line antibiotics, 93.4% of the most commonly isolated uropathogenic species were susceptible to the first-line antibiotics amoxicillin/clavulanic acid (AMC) and 87.6% to trimethoprim-sulfamethoxazole (SXT), while 76.1% showed decreased susceptibility to ampicillin (AMP). Multidrug resistance (MDR) was detected in 11.9% of E. coli, 50.4% of enterococci, and 42.7% of CoPS; 90.6% of these isolates were susceptible to nitrofurantoin (NIT). Our data indicate that empiric treatment of UTI with AMC or SXT could be recommended and is preferable to treatment with AMX. NIT should be considered for the treatment of MDR uropathogens.

Pathogenomics and clinical recurrence influence biofilm capacity of Escherichia coli isolated from canine urinary tract infections

Biofilm formation enhances bacteria’s ability to colonize unique niches while protecting themselves from environmental stressors. Escherichia coli that colonize the urinary tract can protect themselves from the harsh bladder environment by forming biofilms. These biofilms promote persistence that can lead to chronic and recurrent urinary tract infections (UTI). While biofilm formation is frequently studied among urinary E. coli, its association with other pathogenic mechanisms and adaptations in certain host populations remains poorly understood. Here we utilized whole genome sequencing and retrospective medical record analysis to investigate associations between the population structure, phenotypic resistance, resistome, virulome, and patient demographic and clinical findings of 104 unique urinary E. coli and their capacity to form biofilms. We show that population structure including multilocus sequence typing and Clermont phylogrouping had no association with biofilm capacity. Among clinical factors, exposure to multiple antibiotics within that past 30 days and a clinical history of recurrent UTIs were positively associated with biofilm formation. In contrast, phenotypic antimicrobial reduced susceptibility and corresponding acquired resistance genes were negatively associated with biofilm formation. While biofilm formation was associated with increased virulence genes within the cumulative virulome, individual virulence genes did not influence biofilm capacity. We identified unique virulotypes among different strata of biofilm formation and associated the presence of the tosA/R-ibeA gene combination with moderate to strong biofilm formation. Our findings suggest that E. coli causing UTI in dogs utilize a heterogenous mixture of virulence genes to reach a biofilm phenotype, some of which may promote robust biofilm capacity. Antimicrobial use may select for two populations, non-biofilm formers that maintain an arsenal of antimicrobial resistance genes to nullify treatment and a second that forms durable biofilms to avoid therapeutic insults.

Application of pharmacokinetic/pharmacodynamic concepts to the development of treatment regimens for sporadic canine urinary tract infections: Challenges and paths forward

Antimicrobial efficacy can be predicted based on infection site exposure to the antimicrobial agent relative to the in vitro susceptibility of the pathogen to that agent. When infections occur in soft tissues (e.g., muscle, blood, and ligaments), exposure at the infection site is generally assumed to reflect an equilibrium between the unbound concentrations in plasma and that in the interstitial fluids. In contrast, for sporadic urinary tract infections (UTIs) in dogs and uncomplicated UTIs in humans, the primary site of infection is the bladder wall. Infection develops when bacteria invade the host bladder urothelium (specifically, the umbrella cells that form the urine-contacting layer of the stratified uroepithelium) within which these bacteria can avoid exposure to host defenses and antimicrobial agents. Traditionally, pathogen susceptibility has been estimated using standardized in vitro tests that measure the minimal concentration that will inhibit pathogen growth (MIC). When using exposure-response relationships during drug development to explore dose optimization, these relationships can either be based upon an assessment of a correlation between clinical outcome, drug exposure at the infection site, and pathogen MIC, or upon benchmark exposure-response relationships (i.e., pharmacokinetic/pharmacodynamic indices) typically used for the various drug classes. When using the latter approach, it is essential that the unbound concentrations at the infection site be considered relative to the MIC within the biological matrix to which the pathogen will be exposed. For soft tissue infections, this typically is the unbound plasma concentrations versus MICs determined in standardized media such as cation-adjusted Mueller Hinton broth, which is how many indices were originally established. However, for UTIs, it is the unbound drug concentrations within the urine versus the MICs in the actual urine biophase that needs to be considered. The importance of these relationships and how they are influenced by drug resistance, resilience, and inoculum are discussed in this review using fluoroquinolones and beta-lactams as examples.

Cystoscopic Abnormalities in Dogs Presented for Episioplasty

A recessed vulva is a conformational abnormality that predisposes affected dogs to urinary tract infections. An episioplasty can be recommended for correction of this abnormality when medical management of recurrent urinary tract infection fails. The objective of this study was to investigate the type and incidence of urogenital abnormalities visualized by cystoscopy in dogs presenting for episioplasty. Medical records of 29 dogs that presented for an episioplasty and had a concurrent or prior cystoscopy were reviewed. Eleven of the 29 dogs had urogenital abnormalities diagnosed on cystoscopic evaluation, and 1 dog was diagnosed with a urogenital abnormality during vaginal examination while under general anesthesia. Ten of the dogs with urogenital abnormalities had a corrective procedure performed, 8 of which were cystoscopically assisted. Cystoscopy provides the ability to directly visualize the urinary tract and obtain samples for biopsy and culture and facilitates correction of some anatomic abnormalities that may predispose the patient to developing recurrent urinary tract infections. Cystoscopy should be considered as a routine part of a thorough evaluation of the urinary tract in cases presenting for episioplasty.

Genomic and Temporal Trends in Canine ExPEC Reflect Those of Human ExPEC

Companion animals and humans are known to share extraintestinal pathogenic Escherichia coli (ExPEC), but the extent of E. coli sequence types (STs) that cause extraintestinal diseases in dogs is not well understood. Here, we generated whole-genome sequences of 377 ExPEC collected by the University of Melbourne Veterinary Hospital from dogs over an 11-year period from 2007 to 2017. Isolates were predominantly from urogenital tract infections (219, 58.1%), but isolates from gastrointestinal specimens (51, 13.5%), general infections (72, 19.1%), and soft tissue infections (34, 9%) were also represented. A diverse collection of 53 STs were identified, with 18 of these including at least five sequences. The five most prevalent STs were ST372 (69, 18.3%), ST73 (31, 8.2%), ST127 (22, 5.8%), ST80 (19, 5.0%), and ST58 (14, 3.7%). Apart from ST372, all of these are prominent human ExPEC STs. Other common ExPEC STs identified included ST12, ST131, ST95, ST141, ST963, ST1193, ST88, and ST38. Virulence gene profiles, antimicrobial resistance carriage, and trends in plasmid carriage for specific STs were generally reflective of those seen in humans. Many of the prominent STs were observed repetitively over an 11-year time span, indicating their persistence in the dogs in the community, which is most likely driven by household sharing of E. coli between humans and their pets. The case of ST372 as a dominant canine lineage observed sporadically in humans is flagged for further investigation. IMPORTANCE Pathogenic E. coli that causes extraintestinal infections (ExPEC) in humans and canines represents a significant burden in hospital and veterinary settings. Despite the obvious interrelationship between dogs and humans favoring both zoonotic and anthropozoonotic infections, whole-genome sequencing projects examining large numbers of canine-origin ExPEC are lacking. In support of anthropozoonosis, we found that most STs from canine infections are dominant human ExPEC STs (e.g., ST73, ST127, ST131) with similar genomic traits, such as plasmid carriage and virulence gene burden. In contrast, we identified ST372 as the dominant canine ST and a sporadic cause of infection in humans, supporting zoonotic transfer. Furthermore, we highlight that, as is the case in humans, STs in canine disease are consistent over time, implicating the gastrointestinal tract as the major community reservoir, which is likely augmented by exposure to human E. coli via shared diet and proximity.

Detection of Escherichia coli and Enterococcus spp. in dogs with polymicrobial urinary tract infections: A 5-year retrospective study

Background

Urinary tract infections (UTI) caused by Escherichia coli and Enterococcus spp., which are frequently coisolated in polymicrobial UTI, cause morbidity among dogs and warrant antimicrobial therapy.

Objectives

To evaluate clinical features of dogs with polymicrobial E. coli and Enterococcal UTI.

Animals

Forty‐four client‐owned dogs with polymicrobial bacteriuria and groups of 100 client‐owned dogs with E. coli and Enterococcal monomicrobial bacteriuria.

Methods

Retrospective cohort study of medical records of dogs at a university teaching hospital from 2014 to 2019. Prevalence of recurrent UTI and isolate antimicrobial resistance were determined. Clinical outcomes of dogs with recurrent UTI from groups including cost and hospital visits were compared.

Results

Recurrent UTI was more prevalent (P = .05) in dogs with polymicrobial bacteriuria (57%, 95% confidence interval [95% CI]: 42%‐70%) compared to the Enterococcal monomicrobial group (40%, 95% CI: 31%‐50%). Escherichia coli from polymicrobial bacteriuria were more frequently resistant to doxycycline (P < .01, 43%, 95% CI: 29%‐58%) and gentamicin (P = .03, 17%, 95% CI: 9%‐31%) compared to E. coli from monomicrobial bacteriuria (17% and 5%, 95% CI: 11%‐26% and 2%‐11% for doxycycline and gentamicin, respectively). Dogs with recurrent UTI from the polymicrobial UTI group had significantly (P = .05) more hospital visits (mean = 6 visits, 95% CI: 1.7‐9.8) compared to recurrent monomicrobial UTI dogs (mean = 4 and 3 visits, 95% CI: 1.0 to 4.4 and −0.7 to 7.7 for E. coli and Enterococcal monomicrobial UTI, respectively).

Conclusions and Clinical Importance

Escherichia coli and Enterococcus spp. polymicrobial UTI had more frequent adverse clinical outcomes for dogs.

Antimicrobial Resistance in Bacteria Isolated From Canine Urine Samples Submitted to a Veterinary Diagnostic Laboratory, Illinois, United States

The emergence of antimicrobial resistance (AMR) in dogs constitutes a threat to animal and human health. There is a lack of studies in Illinois that evaluated the prevalence of AMR among urinary bacterial pathogens. In the study, we included 803 isolates (299 Gram-positive and 504 Gram-negative) that were isolated from 2,583 canine urine samples submitted to the Veterinary Diagnostic Laboratory, the University of Illinois between 2019 and 2020 from dogs suspected of urinary tract infections (UTI). The most common Gram-positive isolates included Staphylococcus pseudintermedius (17.93%), Enterococcus faecalis (9.46%), Streptococcus canis (6.10%), and Enterococcus faecium (3.74%), while Gram-negative isolates included Escherichia coli (45.58%), Proteus mirabilis (11.08%), Klebsiella pneumoniae (3.11%), and Pseudomonas aeruginosa (2.99%). Among the Gram-positive isolates, Staphylococcus pseudintermedius isolates showed a very high prevalence of resistance to penicillin (56.94%), a high prevalence of resistance to trimethoprim-sulfamethoxazole (31.94%), enrofloxacin (29.17%), and oxacillin (27.08%). Among Gram-negative bacteria, Escherichia coli isolates showed a high prevalence of resistance to ampicillin (31.42%). Considering the high prevalence of resistance to antimicrobials commonly used to treat UTI in dogs, urine samples should be collected for bacterial culture and susceptibility testing before treatment initiation to prevent treatment failures and the development of multidrug resistance. Given the possibility of zoonotic transmission of antimicrobial-resistant bacteria, veterinarians when treating UTI cases, should inform dog owners of the potential transmission risk.

Characterization and Comparison of Enterococcus spp. Isolates from Feces of Healthy Dogs and Urine of Dogs with UTIs

Simple Summary

Infections caused by Enterococcus spp. represent a serious threat to human and animal health due to difficulties in treatment. Indeed, these bacteria are a very able “trafficker” of antimicrobial resistance genes and for this reason they are often resistant to many antimicrobials. In this study we explored the role of pet dogs as possible carriers and targets of antimicrobial resistant and virulent enterococci. Isolates collected from feces of healthy animals and urine of dogs suffering with UTIs were characterized and compared. Strains resulted as resistant to many of the antimicrobials tested and almost of them were multidrug-resistant. Diffuse resistance was recorded for compounds routinely employed in human and pet therapy. Genes responsible for antimicrobial resistance were widely detected. E. faecalis and E. faecium resulted as equally distributed in stool samples, while E. faecalis prevailed among UTI isolates; virulence genes were more often detected in bacteria belonging to this species. Our data confirm that enterococci inhabitant of the gut flora probably represent the main source of UTI in dogs. Furthermore, healthy and sick pet dogs could be spreaders of antimicrobial and virulent enterococci, representing a possible hazard for other animals and owners.

Abstract

Enterococcus spp. are opportunistic pathogens of both humans and animals characterized by high resistance to antimicrobials. Dogs could be intestinal carriers or suffer from Enterococcus infections, mainly urinary tract infections (UTIs). This study aimed to analyze and compare Enterococcus spp. isolated from healthy dog stools and sick dog urine. Overall, 51 isolates (29 from stools and 22 from UTI) were characterized at species level and tested for antimicrobial resistance, biofilm production and presence of resistance and virulence genes. E. faecium and E. faecalis resulted as equally distributed in stools samples, while E. faecalis predominated among UTI isolates. HLAR phenotype was detected in 47.1% isolates; 64.7% isolates were resistant to ampicillin (47.1% with a MIC ≥ 64 µg/mL). High levels of resistance were recorded for fluoroquinolones (enrofloxacin 74.5%, ciprofloxacin 66.7%), clindamycin (84.3%), tetracycline (78.4%) and quinupristin–dalfopristin (78.4%). No vancomycin resistant strains were detected. All but one isolate were multidrug-resistant. Most detected resistance genes were tetM (70.5%), pbp4 (52.9%) and aph(3′)-IIIa (39.2%). All isolates were able to produce biofilm, but isolates from UTIs and belonging to E. faecalis more frequently resulted in strong biofilm producers. Most detected virulence genes were asa1 (52.9%), gelE (41.2%), cylA (37.3%) and esp (35.3%); all of them resulted as more frequently associated to E. faecalis. No particular differences emerged between isolates from feces and UTI, considering all evaluated aspects. Our results confirm pet dogs as carriers of multidrug-resistant enterococci; stool microflora could be considered as the most probable source of enterococcal UTI and E. faecalis carried by dogs seems to be more virulent than E. faecium, justifying its more frequent involvement in urinary tract infections.

Antimicrobial drug resistance profile of isolated bacteria in dogs and cats with urologic problems at Chiang Mai University Veterinary Teaching Hospital, Thailand (2012-2016)

The present study aimed to estimate the proportion of bacterial urinary tract infection (UTI) in dogs and cats, assess risks associated with bacterial UTI, and to determine bacterial isolates' antimicrobial susceptibility and resistance pattern from the urinary tract of dogs and cats with urologic problems. The medical records from animals visiting Chiang Mai University Small Animal Veterinary Teaching Hospital between January 2012 and December 2016 were reviewed. In total, 203 dogs and 49 cats with urinary tract diseases that had samples submitted for bacterial culture were identified;198 and 24 bacterial isolates were recovered from dogs' and cats' submitted samples, respectively. At least one episode of bacterial UTI was detected in 75.4% (95% CI: 69.4-81.3) of dogs and in 40.8% (95% CI: 26.6-55.1) of cats with UTI and submitted urine cultures. Of 242 submitted urinary samples from dogs and 60 urinary samples from cats, bacteria were identified in 74.0% (95% CI: 68.4-79.5) and 38.3% (95% CI: 26.0-50.6), respectively. The most common pathogen of bacteria positive cultured from dogs was Staphylococcus spp. (30.3%), followed by Escherichia coli (16.7%), and Proteus spp. (13.6%). For cats, the most common pathogen was Pseudomonas spp. (25.0%), followed by E. coli (20.8%) and Proteus spp. (16.7%). Staphylococcus spp. isolates from dogs and Proteus spp. isolates from cats were highly susceptible to Amoxicillin/clavulanic acid (AMC) at 88% and 75%, respectively. Of all isolated bacteria, 67.1% of the bacteria from dogs and 83.3% from cats were multidrug-resistant (MDR). The proportion of MDR-bacterial urinary tract infections in dogs and cats with urologic problems in this study was high. This observation raises concerns regarding the potential of zoonotic transmission of MDR-bacteria from these companion animals. The results suggested that AMC remains a good empirical drug for treating UTIs in dogs in this region.

Infections of the Urinary Tract of Bacterial Origin in Dogs and Cats

The diseases of the urinary tract in small animal medicine, especially in dogs and cats, occur frequently with different etiologies. The most common cause of urinary tract infections (UTIs) are bacteria which enter upwards through the urethral opening. UTIs occur in hosts with compromised defence mechanisms in which the virulent microbes can adhere, multiply and persist in the urinary tract. In addition to bacteria, also viruses or fungi may infect the urinary tracts. Bacterial infection can develop in the upper (kidneys and ureters) or lower (bladder, urethra) urinary tract and are manifested by various clinical signs such as: frequent or difficult and painful urination, presence of blood in the urine, or its foul odour. The symptoms in sick animals are often accompanied by fever, discomfort, and loss of appetite. The UTIs in dogs and cats are caused by both Gram-negative (e. g. Escherichia coli, Pseudomonas aeruginosa, Klebsiella spp., Proteus spp.) and Gram-positive (e. g. Staphylococcus spp., Streptococcus spp., and Enterococcus spp.) bacteria. The properly performed aseptic sampling of the urine is one of the most important steps in bacteriological diagnostics. In this study, 105 urine samples were collected from dogs and cats. The cultivation, microscopy and biochemical examinations were used for species identification. Finally, the bacteriological examination included also determining the susceptibility of pathogens against antibiotics by the disc-diffusion method. The results were processed and expressed as a percentage according to identified pathogens, animal species, sex, breed and age. The uropathogens were diagnosed mainly in males aged 7—10 years. The most commonly identified pathogens were Escherichia coli, Streptococcus spp. and Staphylococcus spp. Tests of bacterial susceptibility to antibiotics showed that enrofloxacin, cefotaxime, and cephazolin were the most effective against uropathogens.

Association between case signalment and disease diagnosis in urinary bladder disease in Australian cats and dogs

Urinary bladder diseases are common in dogs and cats; however, there is little published work on urinary bladder disease in Australian pets. We identified pathology records of Australian dogs and cats with urinary bladder tissue submitted to the University of Queensland Veterinary Laboratory Service during 1994-2016 (n = 320). We described the proportion of bladder diseases in dogs and cats, and applied the less-commonly used logistic regression procedure to quantify associations between signalment variables and disease diagnosis that were evident using descriptive statistics alone. After preliminary analysis, both species were combined because of similar results. Spayed/castrated animals were 74% less likely to be diagnosed with cystitis compared with intact animals. Animals 4-11 y old were also at lower risk of being diagnosed with cystitis compared with younger or older animals. Male animals were at increased risk of neoplasia compared to females, which contrasts with reports from North America and Europe. There was increased risk for developing neoplasia with progressive age, with up to 20 times higher odds in the > 11-y age group. Logistic regression modeling provided unique insight into proportionate morbidity of urinary bladder diseases in Australian dogs and cats.

Assessment of bacterial and fungal populations in urine from clinically healthy dogs using next-generation sequencing

BACKGROUND

Urine from clinically healthy dogs is not sterile. Characterizing microbial diversity and abundance within this population of dogs is important to define normal reference ranges for healthy urine.

OBJECTIVES

To establish composition and relative representation of bacterial and fungal microbiomes in urine of clinically healthy dogs.

ANIMALS

Fifty clinically healthy dogs.

METHODS

Analytic study. Urine sampling via cystocentesis. Comprehensive evaluation of urine including standard urinalysis, culture and sensitivity, next-generation sequencing (NGS), and bioinformatics to define bacterial and fungal microbiome.

RESULTS

Culture did not yield positive results in any samples. Next-generation sequencing of urine established low presence of bacteria, fungi, or both in all samples. Diversity and abundance of bacterial and fungal communities varied between urine samples from different dogs. Struvite crystals were associated with bacterial community structure (P = .07) and there was a positive correlation between struvite crystals and pH.

CONCLUSIONS AND CLINICAL IMPORTANCE

The microbiome in urine of clinically healthy dogs has diverse bacterial and fungal species These findings highlight limitations of conventional culture testing and the need for culture-independent molecular diagnostics to detect microorganisms in urine.

Risk factors for urinary bacterial growth in dogs with congenital portosystemic shunts: 66 cases (1997-2019)

OBJECTIVE

To identify risk factors for urinary bacterial growth in dogs with confirmed congenital portosystemic shunts on which a quantitative urine culture was performed.

MATERIALS AND METHODS

Sixty-six dogs were included in this retrospective cross-sectional study. Medical records were reviewed from 1997 through 2019. Variables of interest included age, sex and sexual status, clinical signs for a urinary tract infection, blood urea concentration, urinalysis abnormalities, ultrasound abnormalities of the urinary tract, and previous treatment. Univariable and multivariable analyses were performed.

RESULTS

The median age of the dogs was one year (range: 0.2-11.0 years). Urinary tract ultrasound abnormalities (cystic calculi and cystic debris) were reported in 50 dogs (75.7%). Abnormalities on urinalysis included pyuria in nine dogs (13.6%), bacteriuria in 13 dogs (19.7%), and haematuria in 26 dogs (39.4%). The median urine specific gravity was 1.021 (range: 1.004-1.052). Sixteen dogs (24.2%) had a positive quantitative urine culture. Based on multivariable analysis, bacteriuria (Odds ratio, 116; 95% CI, 9.6-1393; P = < 0.001) was the only variable significantly associated with a significantly increased odds for a positive quantitative urine culture.

CLINICAL SIGNIFICANCE

Clinical and subclinical bacteriuria can occur in dogs with congenital portosystemic shunts. In this group of dogs, bacteriuria was a risk factor for urinary bacterial growth.

Prevalence and Characterization of Urinary Tract Infection in Owned Dogs and Cats From Spain

Bacterial urinary tract infection (UTI) is a common clinical concern in dogs. However, incidence of feline UTI is much lower than in dogs although an increasing prevalence has been registered. The main objective of the present study was to describe and characterize the prevalence of urinary tract pathogens in urine samples of dogs and cats with urinary clinical signs throughout different Spanish provinces. Secondary aims were to determine if there were differences in urine sample characterizations based on species (i.e., dog and cat) or season. Dogs were found to have a higher rate of positive urinary cultures than cats (39.3% and 24.7% of the cultures submitted, respectively). The bacterial genera most commonly isolated in dogs were Escherichia spp. (45.3%), Proteus spp. (13.2%), Staphylococcus spp. (11%), and Enterococcus spp. (8.6%). Whereas in the feline population, Escherichia spp. (42.7%), Enterococcus spp. (22.2%), and Staphyloccoccus spp. (15.2%) were the most frequently isolated bacteria. The highest rates of positive urine cultures were registered in Melilla (70%), Zamora (66.7%), Teruel (64.3%), and Guadalajara (60%). Moreover, the proportion of positive urine cultures was not homogeneously distributed across provinces. Finally, some seasonality was found among most isolated bacterias. Enterococcus spp. was significantly more prevalent in summer, whereas Escherichia spp. and Proteus spp. were more commonly isolated in spring and Pseudomonas spp. in autumn.

Antimicrobial resistance increased over an 8-year period in Enterobacteriaceae cultured from canine urine samples

OBJECTIVES

The aims of the present study were to describe the prevalence of positive urinary bacterial culture in dogs, to identify the most commonly isolated microorganisms and to analyse changes in antimicrobial susceptibility patterns over time.

MATERIAL AND METHODS

A retrospective case series was performed using culture and susceptibility results from canine urine samples collected between January 2010 and December 2017. The presence or absence of infection, identity of the bacterium with heaviest growth, and susceptibility profile were recorded for each sample. Trends in the frequency of positive culture and antimicrobial resistance were assessed by Poisson regression modelling. Prevalence rate ratio and 95% confidence interval were reported for resistance to each antimicrobial.

RESULTS

A positive urine culture was documented in 771 (22.5%) of 3420 samples. Escherichia coli was the most commonly isolated microorganism. There was no significant increase in the frequency of positive bacterial culture over the study period (prevalence rate ratio 0.98; 95% confidence interval: 0.92 to 1.0). Overall, there was an increase in antimicrobial resistance within Enterobacteriaceae from 5.2 to 35.6%. The prevalence of multidrug-resistant bacteria varied from year to year throughout the study period. However, the Poisson regression model identified a significant increase in the frequency of multidrug-resistant Enterobacteriaceae over this period, averaging approximately 22% per year (prevalence rate ratio 1.22, 95% confidence interval: 1.06 to 1.42).

CLINICAL SIGNIFICANCE

The significant increase in antimicrobial resistance observed in this study is concerning and may have implications for veterinary and public health. Appropriate measures, such as antibiotic stewardship programmes, should be implemented to address increasing antimicrobial resistance.

Molecular Characteristics of Extraintestinal Pathogenic E. coli (ExPEC), Uropathogenic E. coli (UPEC), and Multidrug Resistant E. coli Isolated from Healthy Dogs in Spain. Whole Genome Sequencing of Canine ST372 Isolates and Comparison with Human Isolates Causing Extraintestinal Infections

Under a one health perspective and the worldwide antimicrobial resistance concern, we investigated extraintestinal pathogenic Escherichia coli (ExPEC), uropathogenic E. coli (UPEC), and multidrug resistant (MDR) E. coli from 197 isolates recovered from healthy dogs in Spain between 2013 and 2017. A total of 91 (46.2%) isolates were molecularly classified as ExPEC and/or UPEC, including 50 clones, among which (i) four clones were dominant (B2-CH14-180-ST127, B2-CH52-14-ST141, B2-CH103-9-ST372 and F-CH4-58-ST648) and (ii) 15 had been identified among isolates causing extraintestinal infections in Spanish and French humans in 2015 and 2016. A total of 28 (14.2%) isolates were classified as MDR, associated with B1, D, and E phylogroups, and included 24 clones, of which eight had also been identified among the human clinical isolates. We selected 23 ST372 strains, 21 from healthy dogs, and two from human clinical isolates for whole genome sequencing and built an SNP-tree with these 23 genomes and 174 genomes (128 from canine strains and 46 from human strains) obtained from public databases. These 197 genomes were segregated into six clusters. Cluster 1 comprised 74.6% of the strain genomes, mostly composed of canine strain genomes (p < 0.00001). Clusters 4 and 6 also included canine strain genomes, while clusters 2, 3, and 5 were significantly associated with human strain genomes. Finding several common clones and clone-related serotypes in dogs and humans suggests a potentially bidirectional clone transfer that argues for the one health perspective.

Antimicrobial resistance patterns of Pseudomonas aeruginosa isolated from canine clinical cases at a veterinary academic hospital in South Africa

Although Pseudomonas aeruginosa (P. aeruginosa) can infect both animals and humans, there is a paucity of veterinary studies on antimicrobial resistance of P. aeruginosa in South Africa. Secondary data of canine clinical cases presented at the hospital from January 2007 to December 2013 was used. The following information was recorded: type of sample, the date of sampling and the antimicrobial susceptibility results. Frequencies, proportions and their 95% confidence intervals were calculated for all the categorical variables. In total, 155 P. aeruginosa isolates were identified and included in this study. All the isolates were resistant to at least one antimicrobial (AMR), while 92% were multi-drug resistant (MDR). Most isolates were resistant to lincomycin (98%), penicillin-G (96%), orbifloxacin (90%), trimethoprim-sulfamethoxazole (90%) and doxycycline (87%). A low proportion of isolates was resistant to imipenem (6%), tobramycin (12%), amikacin (16%) and gentamicin (18%). A high proportion of MDR-P. aeruginosa isolates was resistant to amoxycillin-clavulanic acid (99%), tylosin (99%), chloramphenicol (97%) and doxycycline (96%). Few (6%) of MDR-P. aeruginosa isolates were resistant to imipenem. Pseudomonas aeruginosa was associated with infections of various organ systems in this study. All P. aeruginosa isolates of P. aeruginosa exhibited resistance to β-lactams, fluoroquinolones and lincosamides. Clinicians at the hospital in question should consider these findings when treating infections associated with P. aeruginosa.

[Bacterial urinary tract infection and subclinical bacteriuria in the dog: a current review]

Bacterial urinary tract infection (UTI) is a common clinical presentation in dogs and a frequent reason for the prescription of antimicrobial drugs. UTI refers to adherence, multiplication and persistence of an infectious agent within the urogenital system. This causes an associated inflammatory response as well as the pertaining clinical signs. Depending on the site of infection, UTI's may be classified as bacterial cystitis, prostatitis or pyelonephritis. In contrast, subclinical bacteriuria (SB) is defined as the presence of a significant number of bacteria in the urine of an individual not showing clinical signs referrable to UTI. UTI's typically occur as a consequence of ascending pathogen migration from the host's own fecal or distal urogenital microbial flora. The most commonly isolated pathogen in cases of UTI and SB is Escherichia coli. The diagnosis is based on clinical signs and the results of urine examination and culture. The recently revised guidelines of the International Society for Companion Animal Infectious Diseases provide detailed recommendations for diagnosis and management of different forms of bacterial UTI's in dogs. Adherence to treatment guidelines will improve treatment success and is imperative in avoiding further deterioration of the antimicrobial resistance situation.

Comprehensive phenotypic and genotypic characterization and comparison of virulence, biofilm, and antimicrobial resistance in urinary Escherichia coli isolated from canines

Urinary tract infections (UTIs) affect nearly half of women and an estimated 14 % of the canine companion animal population at least once in their lifetime. As with humans, Escherichia coli is the most commonly isolated bacteria from canine UTIs and infections are dominated by specific phylogenetic groups with notable virulence attributes. In this study, we evaluated uropathogenic E. coli (UPEC) (n = 69) isolated from canine UTIs phenotypically and genotypically for virulence factors, biofilm formation and antimicrobial resistance profiles. Biofilm formation in UPEC strains was positively associated with common virulence factors including papG (p = 0.006), fimH (p < 0.0001), sfaS (p = 0.004), focA (p = 0.004), cnf-1 (p = 0.009) and hlyA (p = 0.006). There was a negative association between biofilm formation and phenotypic antimicrobial resistance for ampicillin (p < 0.0004), ciprofloxacin (p < 0.0001), and trimethoprim-sulfamethoxazole (p < 0.02), as well as multidrug resistance (isolates resistant to ≥ 3 classes of antimicrobials) (p < 0.0002), and the presence of extended spectrum beta-lactamase (ESBL)-producing genes (p < 0.05). In conclusion, UPECs isolated from clinical cases of canine UTIs show a broad negative association between antimicrobial resistance and biofilm formation, and this observation is supported both by phenotypic and genotypic endpoints. As the biofilm formation may result in antimicrobial tolerance, this could be a secondary evasive tactic of UPEC lacking traditional antimicrobial resistance traits. This observation is important for veterinary practitioners to consider when treating puzzling chronic intractable and/or recurrent cases of UTI that appear to be susceptible to antimicrobial therapy via traditional antimicrobial susceptibility testing (AST) methods.

Chronic osteomyelitis in canine penile bone: case report

ABSTRACT A 10-year-old male mixed-breed dog was admitted for recurrent signs of urinary tract infection (UTI). Urinary bladder ultrasonography revealed decreased thickness of its wall with floating hyperopic particles within its lumen. Ultrasonography revealed a structure invading the dorsal wall of the penile urethral lumen, located in a segment distal to the bladder. Radiographies showed bone resorption with proliferation at the caudal aspect of the penile bone, stricture of the final aspect of the penile urethra, and no radiopaque images compatible with a urethrolith. Computed tomography showed bone proliferation causing stricture of the urethral lumen at two different sites. Presumptive diagnosis of penile neoplasia was considered more likely and the dog underwent penectomy along with orchiectomy and scrotal urethrostomy. Enterobacter spp. was cultured from the urine sample and antibiotic sensitivity tests revealed that the bacterium was susceptible to amikacin, imipenem, and meropenem. Histopathology revealed severe suppurative urethritis, bone resorption, and hyperostosis, suggestive of osteomyelitis of the penile bone. Neoplastic cells were not observed at any part of the examined tissue. The findings in the present case suggest that osteomyelitis of the penile bone should be included in differential diagnosis for partial and complete urethral obstruction in dogs with recurrent UTI.

Antimicrobial resistance among canine enteric Escherichia coli isolates and prevalence of attaching-effacing and extraintestinal pathogenic virulence factors in Spain

The aim of this study was to estimate the prevalence of antimicrobial resistance (AMR) in Escherichia coli from a dog population in Spain and assess specific virulence factors. Susceptibility to 22 antimicrobials was tested along with the production of extended-spectrum β-lactamases (ESBLs) and AmpC in faecal isolates from 100 dogs. Virulence-related genes associated with attaching and effacing E. coli (eae, Stx1, Stx2) and extraintestinal pathogenic E. coli - ExPEC - (papC, hlyA and cnf1) were detected by PCR. At least one kind of AMR was observed in 73% of the isolates. The highest prevalences corresponded to penicillin (45%), aminoglycoside (40%) and non-extended spectrum cephalosporin (39%) classes. Multidrug resistance (MDR) was observed in 53.4% of the resistant isolates. No resistance to colistin was found. Production of ESBL/AmpC enzymes was detected in 5% of E. coli. Shiga toxin-producing E. coli were not observed, enteropathogenic E. coli were identified in only 12% of them, and ExPEC were found in 25%. Dog faeces can be a source of E. coli strains potentially presenting a threat to humans through their virulence factors or AMR. The non-hygienic keeping of animals may increase the risk of colonisation of such pathogens in humans.

Transurethral cystoscopy in dogs with recurrent urinary tract infections: Retrospective study (2011-2018)

Background

Urinary tract infections (UTIs) are common in female dogs and recurrent infections often require investigation by transurethral cystoscopy.

Hypothesis/Objectives

Describe the findings of transurethral cystoscopy in dogs presented for recurrent urinary tract infections (RUTI).

Animals

Fifty‐three client‐owned dogs with RUTI were included in the study.

Methods

Retrospective study. Data collected from medical records included signalment, clinical findings, bladder wall culture, cystoscopic, and histopathologic findings. UTI was defined as: presence of compatible clinical signs and at least 2 out of 3 of the following criteria: (1) pyuria, (2) positive urine culture, (3) resolution of clinical signs with antibiotic treatment. Recurrence of UTI was defined as at least 2 episodes of UTI within 6 months or at least 3 or more in 1 year.

Results

The mean age at presentation was 3.8 years with a majority of female dogs (48/53), 40/48 of which were spayed. Main breeds were Labrador (10/53), Australian Shepherd (4/53), and Miniature Schnauzer (3/53). A hooded vulva was noted in 33/48 of females. Transurethral cystoscopy showed anomalies in 45/53 of cases: mucosal edema (19/53), vestibulovaginal septal remnant (15/48), lymphoid follicles (8/53), short urethra (6/53), and ectopic ureter (5/53). Urine culture at the time of cystoscopy was positive in 13/49. Bladder wall edema and ulceration were the most common findings on histopathology (25/39).

Conclusion and Clinical Importance

RUTI occurred more frequently in spayed female dogs. Transurethral cystoscopy is useful in the diagnosis and treatment of anomalies in dogs with RUTIs.

A clinical approach to multidrug-resistant urinary tract infection and subclinical bacteriuria in dogs and cats

Multidrug-resistant bacteria are increasingly isolated from the urinary tract of pets, particularly those that suffer from concurrent conditions, have been hospitalised, or were treated with antimicrobials in the recent past. Many of the multidrug-resistant bacteria encountered are resistant to all commonly used oral antibiotics. This poses both a therapeutic dilemma in the individual pet and a threat to public health. This article begins with an overview of multidrug resistance in organisms that are commonly isolated from the urinary tract of pets. This is followed by a proposed clinical approach to managing multidrug-resistant urinary bacteria, which summarises current knowledge regarding appropriate sampling and analysis, reviews the current guidelines regarding appropriate antimicrobial use and discusses treatment options that might be considered. The article highlights several shortcomings of the current knowledge to be considered when planning future clinical research and developing policies.

Antimicrobial Susceptibility Patterns and Clinical Parameters in 208 Dogs with Positive Urine Cultures (2012-2014)

Urinary tract infections (UTI) occur commonly in dogs, and gram-negative enteric bacteria are the most prevalent pathogens. Clinical parameters, urinalysis, and urine culture and sensitivity results were retrieved from the medical records of 208 dogs with positive urine cultures over a 3 yr period at the Louisiana State University Veterinary Teaching Hospital. Several groups were defined including dogs presented for primary care versus referred cases; simple UTI, complicated UTI, and pyelonephritis; dogs pretreated with antimicrobials; and dogs having an indwelling catheter in place prior to sampling. Nearly 80% of dogs had complicated UTI. Of all dogs, 70% had no documented clinical signs of lower urinary tract disease (LUTD), with 68% of them showing hematuria and/or pyuria. Based on clinical signs or urinalysis, 19% of all dogs had no evidence of lower UTI. In dogs without LUTD signs the most common comorbidities were immunosuppressive treatment and severely restricted mobility (23%). Chronic recurring UTI were present in 19% of dogs with LUTD signs. Distribution of bacterial species was comparable with the existing literature and not significantly different between clinical subgroups. Isolates from dogs pretreated with antimicrobials showed decreased susceptibility to enrofloxacin. The prevalence of multidrug-resistant Escherichia coli and Staphylococcus spp. was moderate (29%).

Characterization of a bacteriophage with broad host range against strains of Pseudomonas aeruginosa isolated from domestic animals

Background

Pseudomonas aeruginosa is an opportunistic pathogen and one of the leading causes of nosocomial infections. Moreover, the species can cause severe infections in cystic fibrosis patients, in burnt victims and cause disease in domestic animals. The control of these infections is often difficult due to its vast repertoire of mechanisms for antibiotic resistance. Phage therapy investigation with P. aeruginosa bacteriophages has aimed mainly the control of human diseases. In the present work, we have isolated and characterized a new bacteriophage, named Pseudomonas phage BrSP1, and investigated its host range against 36 P. aeruginosa strains isolated from diseased animals and against P. aeruginosa ATCC strain 27853.

Results

We have isolated a Pseudomonas aeruginosa phage from sewage. We named this virus Pseudomonas phage BrSP1. Our electron microscopy analysis showed that phage BrSP1 had a long tail structure found in members of the order Caudovirales. “In vitro” biological assays demonstrated that phage BrSP1 was capable of maintaining the P. aeruginosa population at low levels for up to 12 h post-infection. However, bacterial growth resumed afterward and reached levels similar to non-treated samples at 24 h post-infection. Host range analysis showed that 51.4% of the bacterial strains investigated were susceptible to phage BrSP1 and efficiency of plating (EOP) investigation indicated that EOP values in the strains tested varied from 0.02 to 1.72. Analysis of the phage genome revealed that it was a double-stranded DNA virus with 66,189 bp, highly similar to the genomes of members of the genus Pbunavirus, a group of viruses also known as PB1-like viruses.

Conclusion

The results of our “in vitro” bioassays and of our host range analysis suggested that Pseudomonas phage BrSP1 could be included in a phage cocktail to treat veterinary infections. Our EOP investigation confirmed that EOP values differ considerably among different bacterial strains. Comparisons of complete genome sequences indicated that phage BrSP1 is a novel species of the genus Pbunavirus. The complete genome of phage BrSP1 provides additional data that may help the broader understanding of pbunaviruses genome evolution.

Electronic supplementary material

The online version of this article (10.1186/s12866-019-1481-z) contains supplementary material, which is available to authorized users.

Genetic structure, antimicrobial resistance and frequency of human associated Escherichia coli sequence types among faecal isolates from healthy dogs and cats living in Canberra, Australia

Extraintestinal pathogenic Escherichia coli (ExPEC) cause clinical infections in humans. Understanding the evolution and dissemination of ExPEC strains via potential reservoirs is important due to associated morbidity, health care costs and mortality. To further understanding this survey has examined isolates recovered from the faeces of 221 healthy dogs and 427 healthy cats. The distribution of phylogroups varied with host species, and depended on whether the animal was living in a shelter or a home. The human associated STs 69, 73, 95, 131 and 127 were prevalent, with 30.5% of cat isolates and 10.3% of dog isolates representing these ExPEC sequence types. Resistance to the antibiotics ampicillin and tetracycline was common, but resistance to other antimicrobials was negligible.

Risk factors for Candida urinary tract infections in dogs and cats

BACKGROUND

Candida urinary tract infections occur in both dogs in cats but there is limited data about risk factors.

OBJECTIVE

To identify risk factors for candiduria in dogs in cats.

ANIMALS

Eighteen dogs and 8 cats with candiduria.

METHODS

A retrospective case-control study, using univariate exact logistic regression. Medical records were searched for a diagnosis of Candida and animals with culture-confirmed candiduria were enrolled. Controls had bacterial cystitis (dogs and cats) or cutaneous Malassezia infection (dogs only).

RESULTS

Administration of antibacterial drugs in the 30 days before diagnosis was associated with candiduria in dogs compared to controls with bacterial cystitis (OR 14.5; 95% CI 3.1-66.9) or with Malassezia infection (OR 26.4; 95% CI 3.4-206.7). Antecedent antibacterial drug administration was associated with candiduria in cats (OR 15.7; 95% CI 1.9-132.3). Immunosuppression was associated with candiduria in dogs when compared to controls with Malassezia infection (OR 4.2, 95% CI 1.4-12.8), but not significantly when compared to dogs with bacterial cystitis (OR 2.7, 95% CI 0.9-8.0). Lower urinary tract diseases other than infection were associated with candiduria in cats (OR 6.7, 95% CI 1.6-27.9), but not significantly in dogs (OR 2.5, 95% CI 0.7-8.7). Neither diabetes mellitus nor history of hospitalization was significantly associated with candiduria in either species.

CONCLUSIONS AND CLINICAL IMPORTANCE

The recent administration of antibacterial drug therapy is a potential risk factor for development of candiduria in dogs and cats. Judicious use of antibacterial drugs might help to prevent candiduria.

Characteristics of Dogs with Biofilm-Forming Escherichia Coli Urinary Tract Infections

BACKGROUND

Bacterial urinary tract infections (UTIs) are common in companion animals. Increasing awareness of biofilm-forming bacteria raises concern regarding the appropriate diagnosis, treatment, and prognosis of UTIs associated with these organisms.

HYPOTHESIS/OBJECTIVES

To (1) describe the population of dogs with UTIs associated with biofilm-forming Escherichia coli and (2) determine whether or not clinical differences exist between dogs with biofilm-forming E. coli UTIs and dogs with nonbiofilm-forming E. coli UTIs. We hypothesized that there would be no difference in the population characteristics, but that biofilm-formation would be more prevalent in dogs with chronic, complicated, and asymptomatic UTIs.

ANIMALS

Seventy-six client-owned dogs with E. coli UTIs, divided into 2 groups based on the biofilm-forming capability of stored bacterial isolates as assessed by the crystal violet assay.

METHODS

Retrospective cross-sectional study. Medical records of the affected dogs were reviewed and their population and infection characteristics were compared.

RESULTS

Most (52.6%) E. coli isolates were capable of forming biofilms. Biofilm-forming E. coli had a lower likelihood (P < .001) of multidrug resistance than did nonbiofilm-forming E. coli. No statistically significant differences were identified between the population or infection characteristics of the 2 groups of dogs.

CONCLUSIONS AND CLINICAL IMPORTANCE

Escherichia coli isolated from canine urinary tracts are frequently capable of forming biofilms. Because no reliable clinical features allowed exclusion of biofilm formation, the potential for biofilm formation should be considered whenever E. coli UTI is diagnosed. The association of antibiotic resistance and biofilm potential may affect treatment of UTIs, but additional investigation is warranted.

Antimicrobial resistance among Escherichia coli isolates from dogs presented with urinary tract infections at a veterinary teaching hospital in South Africa

Background

This study investigated the burden and predictors of canine E. coli urinary tract infections (UTI) and antimicrobial resistance among dogs presented at a veterinary teaching hospital in South Africa, 2007–2012.

Methods

The Cochran-Armitage trend test was used to investigate temporal trends while logistic regression models were used to investigate predictors (age, sex, breed, year) of E. coli infections and antimicrobial resistance (AMR).

Results

A total of 22.3% (168/755) of the urinary specimens tested positive for E. coli. A significant (p = 0.0004) decreasing temporal trend in the percentage of E. coli positive isolates was observed over the study period. There were high levels of AMR to penicillin-G (99%), clindamycin (100%), tylosine (95%), cephalothin (84%) but relatively low levels of resistance to enrofloxacin (16%), orbifloxacin (21%). Almost all (98%, 164/167) the isolates exhibited multidrug resistance (MDR), while only 11% (19/167) and 2% (4/167) exhibited extensive drug resistance (XDR) and pan-drug resistance (PDR), respectively.

Conclusions

Although, the risk of E. coli UTI declined during the study period, the risk of AMR increased. The high levels of AMR and MDR as well as the presence of XDR and PDR is concerning as these have the potential of affecting prognosis of UTI treatments.

Evaluation of the Live Biotherapeutic Product, Asymptomatic Bacteriuria Escherichia coli 2-12, in Healthy Dogs and Dogs with Clinical Recurrent UTI

Background

Antimicrobial resistance is an emerging problem.

Hypothesis/Objective

To investigate the safety and efficacy of a live biotherapeutic product, ASB E. coli 2‐12 for UTI treatment.

Animals

Six healthy research dogs; nine client‐owned dogs with recurrent UTI.

Methods

Prospective noncontrolled clinical trial. For safety data, research dogs were sedated, a urinary catheter was inserted into the bladder; 10¹⁰CFU/mL of ASB E. coli 2‐12 was instilled. Urine was cultured on days 1, 3, and 8 post‐instillation and dogs were observed for lower urinary tract signs (LUTS). For client‐owned dogs, ASB E. coli 2‐12 was instilled similarly and urine cultures analyzed on days 1, 7, and 14 days postinstillation.

Results

No LUTS were noted in any of the 6 research dogs after ASB E. coli 2‐12 infusion. Pulse field gel electrophoresis (PFGE) studies confirmed the bacterial strains isolated matched that ASB E. coli 2‐12 strain. Four of the nine client‐owned dogs had complete or nearly complete clinical cures by day 14. Of these four dogs, 3 also had microbiologic cures at day 14; one of these dogs had subclinical bacteriuria (in addition to ASB E. coli 2‐12). Three of these four dogs had ASB E. coli 2‐12 isolated from their urine at day 14. With the exception of mild, temporary, self‐limiting, hyporexia in two dogs on the day of biotherapeutic administration, there were no major adverse effects.

Conclusions and Clinical Importance

These results suggest ASB E. coli 2‐12 is safe and should be investigated in a larger controlled study evaluating clinical UTI in dogs.

Antimicrobial resistance in clinical Escherichia coli isolated from companion animals in Australia

Multidrug-resistant (MDR) Escherichia coli have become a major public health concern to both humans and animal health. While the frequency of antimicrobial resistance (AMR) in clinical E. coli is monitored regularly in human medicine, current frequency of AMR in companion animals remains unknown in Australia. In this study we conducted antimicrobial susceptibility testing (AST) and where possible, determined potential risk factors for MDR infection among 883 clinical Escherichia coli isolated from dogs (n=514), cats (n=341) and horses (n=28). AST was undertaken for 15 antimicrobial agents according to the Clinical Laboratory Standards Institute (CLSI) guidelines and interpreted using epidemiological cut-off values (ECOFFs) as well as CLSI veterinary and human clinical breakpoints. The AST revealed complete absence of resistance to carbapenems while resistance to amikacin was observed at a low level in isolates from dogs (1.6%) and cats (1.5%) compared to horses (10.7%). Among dog isolates, resistance to fluoroquinolones ranged from 9.1%-9.3% whereas among cat isolates, it ranged from 3.2%-5%. Among dog isolates, the proportion showing a 3rd generation cephalosporin (3GC) non-wild type phenotype was significantly higher (P<0.05) in skin and soft tissue infection (SSTI, n=122) isolates (17.2%-20.5%) compared to urinary tract infection (UTI, n=392) isolates (9.9%-10.2%). The frequency of multidrug resistance was 18.1%, 11.7% and 42.9% in dog, cat and horse isolates, respectively. Risk factor analysis revealed that MDR E. coli isolated from UTI were positively associated with chronicity of infection and previous antimicrobial treatment. Dogs and cats with chronic UTI that had been previously treated with antimicrobials were eight times and six times more likely to be infected with MDR E. coli compared to dogs and cats with non-chronic UTI, and no history of antimicrobial treatment, respectively. This study revealed that pre-existing disease condition and prior antimicrobial use were the major risks associated with UTI with MDR E. coli in companion animals.

Characterization of the urinary microbiome in healthy dogs

The urinary bladder in healthy dogs has dogmatically been considered free of bacteria. This study used culture independent techniques to characterize the healthy canine urinary microbiota. Urine samples collected by antepubic cystocentesis from dogs without urinary infection were used for DNA extraction. Genital tract and rectal samples were collected simultaneously from the same dogs. The V4 hypervariable region of the 16S rRNA bacterial gene was amplified and compared against Greengenes database for OTU assignment and relative abundance for urine, genital, and rectal samples. After excluding 4 dogs with cultivable bacteria, samples from 10 male (M; 1 intact) and 10 female (F) spayed dogs remained. All samples provided adequate genetic material for analysis. Four taxa (Pseudomonas sp., Acinetobacter sp., Sphingobium sp. and Bradyrhizobiaceae) dominated the urinary microbiota in all dogs of both sexes. These taxa were also detected in the genital swabs of both sexes, while the rectal microbiota differed substantially from the other sample sites. Principal component (PC) analysis of PC1 through PC3 showed overlap of urinary and genital microbiota and a clear separation of rectal swabs from the other sample sites along PC1, which explained 44.94% variation. Surprisingly, the urinary microbiota (mean # OTU 92.6 F, 90.2 M) was significantly richer than the genital (67.8 F, 66.6 M) or rectal microbiota (68.3 F, 71.2 M) (p < 0.0001), with no difference between sexes at any sample site. The canine urinary bladder is not a sterile environment and possesses its own unique and diverse microbiota compared to the rectal and genital microbiota. There was no difference between the sexes at any microbiota sample site (urine, genital, and rectal). The predominant bacterial genus for either sex in the urine and genital tracts was Pseudomonas sp.

Assessment of urinary pharmacokinetics and pharmacodynamics of orbifloxacin in healthy dogs with ex vivo modelling

PURPOSE

The aim of this study was to investigate the urinary pharmacokinetics (PK) of orbifloxacin (OBFX) administered at 5 mg kg-1 in six healthy dogs. A further aim was to use an ex vivo model to evaluate the urinary PK and pharmacodynamics (PD) of OBFX to determine its urinary bactericidal titre (UBT), which represents the maximal dilution of urine allowing bactericidal activity.

METHODOLOGY

Fourteen urinary tract infection (UTI) pathogenic strains of five bacterial species (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus mirabilis and Staphylococcuspseudintermedius) were used. Urine samples were obtained every 4 h for the first 24 h after OBFX administration, for measurement of urine drug concentration and UBT.Results/Key findings. The urine OBFX concentration peaked at 0-4, 4-8 or 4-8 h after administration, with a maximum concentration of 383±171 µg ml-1. Overall, the fluctuation in median UBT closely correlated with that of the mean urine OBFX concentration. In addition, the median areas under the UBT-time curves (AUBTs) were significantly inversely correlated with the MICs for OBFX in the tested strains (P<0.01). Notably, median UBTs and AUBTs were extremely low (0-0.5 and 2-5, respectively) in OBFX-resistant E. coli strains with MIC ≥8 µg ml-1.

CONCLUSION

The fluctuation of UBTs closely correlated with that of urine concentration, and UBT values depended on the susceptibility of the bacterial strains to OBFX. We believe that ex vivo modelling to determine UBTs is useful to evaluate the urinary PK/PD of antimicrobials indicated for UTIs in dogs.

Determination of minimum biofilm eradication concentrations of orbifloxacin for canine bacterial uropathogens over different treatment periods

Biofilm formation can cause refractory urinary tract infections (UTIs) in dogs; however, minimum biofilm eradication concentrations (MBECs) of veterinary drugs against canine uropathogens remain to be investigated. In this study, the MBECs of orbifloxacin (OBFX), trimethoprim-sulfamethoxazole (TMS) and amoxicillin/clavulanate (ACV) over different time periods for treatment of canine uropathogenic Escherichia coli (n = 10) were determined. The MBECs of OBFX for other bacterial uropathogens, including Staphylococcus pseudintermedius (n = 5), Pseudomonas aeruginosa (n = 5), Klebsiella pneumoniae (n = 5) and Proteus mirabilis (n = 5) were also determined. Minimum inhibitory concentrations (MICs) were identified for all strains by broth microdilution, and MBECs were determined at 24, 72, and 168 hr using the Calgary biofilm method. The 24 hr MBECs of OBFX, TMS and ACV for the E. coli strains were significantly higher than the MICs (P < 0.05), and the 72 and 168 hr MBECs were significantly lower than those at 24 hr (P < 0.05). In addition, the 24 hr OBFX MBECs for the four other uropathogens were significantly higher than the corresponding MICs (P < 0.05). The 72 and/or 168 hr OBFX MBECs for S. pseudintermedius, K. pneumoniae and P. mirabilis were significantly lower than the 24 hr concentrations (P < 0.05), whereas for P. aeruginosa, no significant difference was found between any of the MBECs (P > 0.05). These data indicate that the administration period and uropathogenic bacterial species are important factors affecting the efficacy of OBFX treatment of biofilm-related UTIs in dogs.

Prevalence of AmpC- and Extended-Spectrum β-Lactamase-Harbouring Enterobacteriaceae in Faecal Flora of a Healthy Domestic Canine Population

In order to estimate the prevalence of AmpC- and ESBL β-lactamase-producing Enterobacteriaceae in the faecal flora of a healthy domestic canine population, faecal samples were obtained from healthy dogs receiving routine parasitology screening at the Ohio State University Veterinary Medical Center, between January 2013 and April 2013. Samples were screened for the presence of AmpC and ESBL β-lactamase phenotypes, and the clinically important genotypes, bla_CMY and bla_CTX-M , were confirmed via conventional PCR. Minimum inhibitory concentrations were determined for isolates and plasmids were characterized. Two hundred and twelve canine faecal samples were screened, of which 30 harboured isolates carrying the AmpC bla_CMY , representing 14.2% of the population (95% CI: 9.4-18.9%). Nine samples harboured isolates that carried the ESBL bla_CTX-M , representing 4.2% of the population (95% CI: 1.5-7.0%). Isolates containing bla_CMY harboured multiple plasmid replicon types, while isolates containing bla_CTX-M harboured few plasmid replicon types. Our results suggest that domestic dogs may serve as a reservoir for extended-spectrum cephalosporin resistance genes for other domestic animal populations as well as for their human companions. This represents a potential veterinary and public health risk that warrants further investigation and continued surveillance to ascertain the nature and extent of the risk. The high level of diversity of plasmid content among isolates harbouring bla_CMY suggests broader dissemination relative to bla_CTX-M isolates.

An investigation of antimicrobial usage patterns by small animal veterinarians in South Africa

AIM

At present very little information is available on antimicrobial use patterns in small animal veterinary practice in South Africa. The aim of this study was firstly to provide some indication of antimicrobial use patterns, and secondly to ascertain if the country's small animal veterinarians make use of prudent use guidelines to optimise their antimicrobial use in order to minimise the development of antimicrobial resistance.

METHODOLOGY

In order to understand use patterns, a questionnaire was circulated to registered South African veterinarians, whose responses were evaluated by descriptive statistics. The prevalence of antimicrobial resistance was evaluated for dogs from samples submitted for culture and susceptibility testing for the period 2007-2013 from the only faculty of Veterinary Science in the country. The resistance data was organized into contingency tables and yearly trends in resistance evaluated by means of a chi-square. The use of antimicrobials from the survey were compared to the laboratory result to ascertain the degree of prudent use of the antimicrobials in small animal practice in a developing country.

RESULTS

The responses from the questionnaire indicated that South African veterinarians predominantly (91.16%) used antimicrobials empirically before resorting to laboratory testing and that antimicrobial compounding and off label use (86.19%) of human registered medication was common practice. A worrying finding was that a large number of clients attempted antimicrobial treatment of their pets prior to seeking veterinary assistance. In terms of monitored resistance, annual prevalence of resistance was above 10% and multiple drug resistance was above 50% for all the isolates.

CONCLUSION

It is concluded that antimicrobial resistant bacteria are present in small companion animal practice in South Africa which requires better implementation of prudent use guidelines.

Surgical management of vesicoureteral reflux with recurrent urinary tract infection after renal transplantation in a dog

CASE DESCRIPTION A 3-year-old male Cocker Spaniel renal transplant recipient was readmitted 39 weeks after transplantation because of acute clinical signs of pollakiuria, intermittent vomiting, decreased appetite, lethargy, and mild fever. CLINICAL FINDINGS Hydronephrosis and hydroureter were observed with ultrasonography and contrast cystography, and a diagnosis of vesicoureteral reflux (VUR) was made. Urinary tract infection (UTI) caused by Escherichia coli was also diagnosed on the basis of results of urine culture. TREATMENT AND OUTCOME Despite treatment of the UTI with an appropriate antimicrobial for 6 weeks, the VUR persisted and the UTI recurred 9 weeks after cessation of antimicrobial treatment. Therefore, surgical correction by means of revision extravesicular ureteroneocytostomy was performed. Both VUR and hydronephrosis resolved after surgery. No recurrences of clinical signs of urinary tract complications were observed during the subsequent 22-month follow-up period. CLINICAL RELEVANCE Results suggested that ureteral reimplantation with an extravesicular technique incorporating a long submucosal tunnel may be an effective treatment for VUR when medical management fails in canine renal transplant recipients with recurrent UTIs.

European multicenter study on antimicrobial resistance in bacteria isolated from companion animal urinary tract infections

BACKGROUND

There is a growing concern regarding the increase of antimicrobial resistant bacteria in companion animals. Yet, there are no studies comparing the resistance levels of these organisms in European countries. The aim of this study was to investigate geographical and temporal trends of antimicrobial resistant bacteria causing urinary tract infection (UTI) in companion animals in Europe. The antimicrobial susceptibility of 22 256 bacteria isolated from dogs and cats with UTI was determined. Samples were collected between 2008 and 2013 from 16 laboratories of 14 European countries. The prevalence of antimicrobial resistance of the most common bacteria was determined for each country individually in the years 2012-2013 and temporal trends of bacteria resistance were established by logistic regression.

RESULTS

The aetiology of uropathogenic bacteria differed between dogs and cats. For all bacterial species, Southern countries generally presented higher levels of antimicrobial resistance compared to Northern countries. Multidrug-resistant Escherichia coli were found to be more prevalent in Southern countries. During the study period, the level of fluoroquinolone-resistant E. coli isolated in Belgium, Denmark, France and the Netherlands decreased significantly. A temporal increase in resistance to amoxicillin-clavulanate and gentamicin was observed among E. coli isolates from the Netherlands and Switzerland, respectively. Other country-specific temporal increases were observed for fluoroquinolone-resistant Proteus spp. isolated from companion animals from Belgium.

CONCLUSIONS

This work brings new insights into the current status of antimicrobial resistance in bacteria isolated from companion animals with UTI in Europe and reinforces the need for strategies aiming to reduce resistance.