Characterisation of bacterial growth and antimicrobial susceptibility patterns in canine urinary tract infections

Significance of scattered small echogenic foci floating in urinary bladder as ultrasonography finding in dogs

BACKGROUND

Despite the prevalence of echogenic foci floating in the urinary bladder seen in ultrasonography in dogs, surprisingly little has been written on its significance, including its potential association with urinalysis. The objective of the study was to determine the diagnostic value of the echogenic foci floating in urinary bladders in dogs.

RESULTS

- Cystosonography was performed on 45 dogs. Bladder contents were examined and divided into positive (containing echogenic particles) and negative (absent echogenic particles) groups according to the presence and absence of floating echogenic particles. Five mL of urine was collected via cystocentesis. Urine analysis and culture were done and the relationship between ultrasound evaluation and urinalysis results was investigated. In dogs with bladder echogenic particles in ultrasonography, the prevalence of hematuria, pyuria, bacteriuria, and lipiduria were 88.9%, 92.6%, 29.6%, and 70.3%, respectively. However, in dogs in which echogenic particles were not observed in their bladders, the prevalence of hematuria, pyuria, bacteriuria, and lipiduria was 77%, 50%, 5.5%, and 77%, respectively. There was a significant association between bladder debris and positive urine culture, with an odds ratio of 7.15 (95% confidence interval: 0.81-63.28) compared with matched controls. Furthermore, there was a significant relationship between the presence of floating echogenic particles with pyuria, and urine color ( p ≤ 0.05).

CONCLUSION

In conclusion, the present results showed the detection of bladder debris on ultrasound can be a predictor for pyuria and positive urine culture in dogs.

Antimicrobial susceptibility patterns of aerobic bacteria isolated from canine urinary samples in South East Queensland, 2013 to 2018

Urinary tract infections are a common diagnosis in dogs presenting to veterinary practice. Veterinarians often treat suspected infections empirically, either in the absence of culture and susceptibility testing results or whilst waiting for them. This study aimed to identify the bacteria most frequently isolated from canine urinary samples and their antimicrobial susceptibility patterns in South East Queensland (SEQ) to help guide responsible empirical antimicrobial prescription by the veterinary community in this geographical location. Cumulative antibiograms were generated from the results of 1284 culture-positive urinary samples in SEQ, obtained from a commercial veterinary laboratory over a 5-year period. Escherichia coli was the most commonly isolated bacterial species (43%), followed by Staphylococcus spp. (23%), Proteus spp. (21%) and Enterococcus spp. (10%). Of the six most common isolates, 97% had susceptibility to at least one low-importance antimicrobial. Susceptibility to the low-importance and first-line antimicrobial recommendation, amoxicillin, was 81% for E. coli and 24% for Staphylococcus spp. Susceptibility of both E. coli and Staphylococcus spp. to medium-importance and commonly recommended empirical antimicrobials, trimethoprim sulphonamides and amoxicillin-clavulanic acid was ≥85% and >92% for high-importance antimicrobials enrofloxacin and ceftiofur. Of the E. coli and Staphylococcus spp. isolates, 8.8% and 4%, respectively, were considered multidrug resistant. There was no increase in resistance to antimicrobials detected over the study period. Susceptibilities suggest low- and medium-importance antimicrobials remain acceptable first-line empirical treatments. However, this should be continually assessed and updated using local surveillance data.

Altered microbiome of serum exosomes in patients with acute and chronic cholecystitis

BACKGROUND

This study aimed to investigate the differences in the microbiota composition of serum exosomes from patients with acute and chronic cholecystitis.

METHOD

Exosomes were isolated from the serum of cholecystitis patients through centrifugation and identified and characterized using transmission electron microscopy and nano-flow cytometry. Microbiota analysis was performed using 16S rRNA sequencing.

RESULTS

Compared to patients with chronic cholecystitis, those with acute cholecystitis exhibited lower richness and diversity. Beta diversity analysis revealed significant differences in the microbiota composition between patients with acute and chronic cholecystitis. The relative abundance of Proteobacteria was significantly higher in exosomes from patients with acute cholecystitis, whereas Actinobacteria, Bacteroidetes, and Firmicutes were significantly more abundant in exosomes from patients with chronic cholecystitis. Furthermore, functional predictions of microbial communities using Tax4Fun analysis revealed significant differences in metabolic pathways such as amino acid metabolism, carbohydrate metabolism, and membrane transport between the two patient groups.

CONCLUSIONS

This study confirmed the differences in the microbiota composition within serum exosomes of patients with acute and chronic cholecystitis. Serum exosomes could serve as diagnostic indicators for distinguishing acute and chronic cholecystitis.

Rapid identification of canine uropathogens by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry and the clinical factors that correlated bacterial species and antimicrobial resistance

Using the matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) method for bacterial diagnosis, rapid urine sample preparation can reduce time relapsing of diagnosis and improve discriminatory power in coinfection cases. We aimed to evaluate rapid urine preparation procedures before MALDI-TOF MS application using dog clinical urine samples in comparison with standard microbiological diagnostic methods by agreement analysis. We determined the frequency and distribution of bacteria and bacterial resistance and their correlations to clinical history. Three experimental procedures comprising direct centrifugation, 10% sodium dodecyl sulfate digestion, and ultrasonic preparation were performed for method validation and sensitivity. Sterile urine containing Escherichia coli and/or Staphylococcus aureus were used as simulated samples. By ultrasonic preparation, the microorganisms could be detected 1.46-1.51 × 105 CFU, which was considered the most suitable technique. This preparation was significantly consistent with the routine method based on data from Hospital Information Systems for 50 urine samples from canine cystitis. By standard protocol, Enterobacteriaceae and Staphylococcus pseudintermedius were found in most of the 155 urine samples with cystitis. Extended-spectrum beta-lactamase-producing Enterobacteriaceae was found in 25-30% of the samples. Imipenem resistance was found in 70% of Acinetobacter baumannii cases; almost all were resistant to second-generation fluoroquinolones and tetracyclines. The most efficient antibiotic for treating bacterial urinary tract infection was amoxicillin plus clavulanic acid. A. baumannii and Pseudomonas aeruginosa were susceptible to pradofloxacin. Prolonged urine catheterization was linked to lower urinary tract infections by Enterobacter spp., which also correlated with chronic kidney disease.

Evaluation of a rapid immunoassay for bacteriuria in dogs

BACKGROUND

The ability to detect bacteriuria in dogs with a point-of-care test might improve medical care and antimicrobial stewardship.

HYPOTHESIS AND OBJECTIVE

A rapid immunoassay (RIA; RapidBac) will provide acceptable sensitivity and specificity for diagnosis of bacteriuria.

ANIMALS

Forty-four client-owned dogs with a clinical indication for urinalysis and aerobic bacterial urine culture.

METHODS

Prospective study. Urine, collected by cystocentesis, was submitted for urinalysis and culture at a diagnostic laboratory. Owners completed an enrollment questionnaire regarding their dogs' clinical signs. The RIA was performed according to the manufacturer's guidelines. Results were compared to culture.

RESULTS

Forty-four urine specimens were evaluated from 44 dogs. The sensitivity and specificity of the RIA test to detect bacteriuria compared to urine culture were 81.8% (95% CI, 65.7%-97.9%) and 95.5% (95% CI, 86.8%-99.9%), respectively. For cultures yielding ≥10³  CFU/mL, sensitivity increased to 90.0% (95% CI, 76.9%-100%) and specificity was similar at 95.2% (95% CI, 86.1%-99.9%). Malodorous urine, bacteriuria, and pyuria were more likely to be present in dogs with positive RIA or urine culture results compared to dogs with negative results.

CONCLUSIONS AND CLINICAL IMPORTANCE

The RIA was easy to perform and had good sensitivity and excellent specificity in this group of dogs. The RIA might be a useful screening test for decision-making regarding antimicrobial therapy in dogs with a clinical indication for urine culture. Consideration could be given to amending the International Society for Companion Animal Infectious Disease definition of bacterial cystitis as the presence of signs of lower urinary tract disease together with positive culture or a positive RIA.

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.

A Retrospective Study of Antimicrobial Resistant Bacteria Associated with Feline and Canine Urinary Tract Infection in Hong Kong SAR, China—A Case Study on Implication of First-Line Antibiotics Use

Urinary tract infection (UTI) is a common clinical diagnosis for which empirical antibiotics are used in veterinary medicine. For veterinarians, the description of canine and feline antibiograms can help with making prudent use decisions and guideline formulation. For public health officers and epidemiologists, a urinary antibiogram overview helps track and trend antimicrobial resistance (AMR). There is currently a knowledge gap in AMR prevalence associated with urinary tract infection in feline and canine patients and the resistance percentage of these microbes against some of the over-the-counter antibiotics available to local pet owners. This study has two aims. First, it aims to investigate the frequency of the bacteria and bacterial-resistance pattern in urine samples obtained from feline and canine patients. Second, it aims to determine the resistance of Escherichia coli (E. coli), the most frequently isolated bacteria, to first-line antibiotics. Results: We identified the five most-frequently isolated bacterial species and determined these isolates’ antibiotic sensitivity and resistance. The most-frequently isolated bacteria in feline and canine patients was Escherichia coli (E. coli). E. coli was identified, on average, in 37.2% of canine and 46.5% of feline urine samples. Among feline urinary samples, Enterococcus (14.7%) and Staphylococcus (14.5%) spp. were isolated more frequently, followed by Pseudomonas (4.8%) and Klebsiella (5.2%) spp. (). In canine samples, Proteus (17.9%) and Staphylococcus (13.2%) spp. were isolated more frequently, followed by Enterococcus (10.0%) and Klebsiella (8.59%) spp. Among these isolates, 40 to 70% of Staphylococcus spp. bacterial isolates from feline and canine patients were resistant to amoxicillin and ampicillin. During the three-year study period, among canine patients, 10 to 20% of Staphylococcus spp. bacterial isolates were resistance to fluoroquinolones, other quinolones, and third-generation cephalosporins. Among feline patients, 10% of Staphylococcus spp., 15 to 20% of E. coli, 50 to 60% of Klebsiella spp., and 90% of Pseudomonas spp. were resistant to cefovecin, a commonly used antibiotic.

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.

Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): antimicrobial‐resistant Escherichia coli in dogs and cats, horses, swine, poultry, cattle, sheep and goats

Escherichia coli (E. coli) was identified among the most relevant antimicrobial‐resistant (AMR) bacteria in the EU for dogs and cats, horses, swine, poultry, cattle, sheep and goats in previous scientific opinions. Thus, it has been assessed according to the criteria of the Animal Health Law (AHL), in particular criteria of Article 7 on disease profile and impacts, Article 5 on its eligibility to be listed, Annex IV for its categorisation according to disease prevention and control rules as in Article 9 and Article 8 for listing animal species related to the bacterium. The assessment has been performed following a methodology previously published. The outcome is the median of the probability ranges provided by the experts, which indicates whether each criterion is fulfilled (lower bound ≥ 66%) or not (upper bound ≤ 33%), or whether there is uncertainty about fulfilment. Reasoning points are reported for criteria with uncertain outcome. According to the assessment here performed, it is uncertain whether AMR E. coli can be considered eligible to be listed for Union intervention according to Article 5 of the AHL (33–66% probability). According to the criteria in Annex IV, for the purpose of categorisation related to the level of prevention and control as in Article 9 of the AHL, the AHAW Panel concluded that the bacterium does not meet the criteria in Sections 1, 2, 3 and 4 (Categories A, B, C and D; 0–5%, 5–10%, 10–33% and 10–33% probability of meeting the criteria, respectively) and the AHAW Panel was uncertain whether it meets the criteria in Section 5 (Category E, 33–66% probability of meeting the criteria). The animal species to be listed for AMR E. coli according to Article 8 criteria include mammals, birds, reptiles and fish.

Patterns of antimicrobial, multidrug and methicillin resistance among Staphylococcus spp. isolated from canine specimens submitted to a diagnostic laboratory in Tennessee, USA: a descriptive study

Background

Multidrug- and methicillin-resistant staphylococci are both veterinary and public health concerns due to their zoonotic potential. Therefore, the objective of this study was to investigate patterns of antimicrobial, multidrug, and methicillin resistance among four Staphylococcus spp. commonly isolated from canine clinical specimens submitted to the Clinical Bacteriology Laboratory at the University of Tennessee College of Veterinary Medicine (UTCVM).

Methods

Results of antimicrobial susceptibility testing and mecA polymerase chain reaction (PCR) for isolates of four common Staphylococcus spp. isolates were obtained from the Bacteriology Laboratory at the UTCVM between 01/01/2006 and 12/31/2017. Cochran-Armitage trend test was used to assess temporal trends of antimicrobial resistance (AMR), multidrug resistance (MDR), and methicillin resistance. Kappa test of agreement was used to assess agreement between the results of PCR and disk diffusion tests.

Results

Most of the 7805 isolates were S. pseudintermedius (6453 isolates), followed by S. coagulans (860), S. aureus (330), and S. schleiferi (162). Among S. pseudintermedius isolates, 45.5% were MDR, and 30.8% were methicillin-resistant (MRSP). There was a significant temporal increase in MRSP (p = 0.017). Chloramphenicol resistance increased among both MRSP and methicillin-susceptible (MSSP) isolates (p <  0.0001). Among S. aureus isolates, 40.9% were MDR, 37.4% were methicillin-resistant (MRSA), and the proportion of MRSA isolates increased significantly (p = 0.0480) over time. There was an increasing temporal trend in the proportion of MDR isolates among MSSP (p = 0.0022), but a decrease among MRSP (p <  0.0001) and MRSA (p = 0.0298). S. schleiferi had the highest percentage (56.9%) of methicillin-resistant isolates. Oxacillin disk diffusion was superior to cefoxitin for the detection of mecA-mediated resistance and had almost perfect agreement with mecA PCR assay for S. pseudintermedius (95.4% agreement, kappa (κ) = 0.904; p <  0.0001), S. coagulans (95.6%, κ = 0.913; p <  0.0001) and S. schleiferi (97.7%, κ = 0.945; p <  0.0001). However, cefoxitin disk diffusion was superior to oxacillin disk diffusion and had almost perfect agreement with mecA PCR assay for S. aureus (95.3%, κ = 0.834; p <  0.0001).

Conclusions

The levels of resistance and increasing temporal trends are concerning. These findings have implications for treatment decisions and public health due to the zoonotic potential of staphylococci. Continued surveillance and use of antibiograms to guide clinical decisions will be critical.

The effect of urine storage temperature and boric acid preservation on quantitative bacterial culture for diagnosing canine urinary tract infection

BACKGROUND

Quantitative bacterial culture (QBC) is the gold standard for diagnosing canine urinary tract infection. Current guidelines recommend QBC within 24 h of urine collection and that unpreserved urine is refrigerated until culture. However, temperature-controlled transport is rarely feasible, indicating a need for alternative storage during transport of urine from primary veterinary practices to the microbiology laboratory. The objective was to investigate the effect of storage temperature and boric acid sponge-preservation on quantitative bacterial culture of canine urine.

RESULTS

Significant bacteriuria was detected in 72 out of 179 samples (40%) collected from 141 dogs. Overall accuracy was 94-98% for both storage conditions and time points. Non-inferiority (15% margin) to reference quantitative bacterial culture was evident for sensitivity, specificity and predictive values for both storage methods and time points, except for the negative predictive value for 48 h boric acid preservation (NPV: 89, 95% CI [79;95]). There was no significant difference between the sensitivity and specificity for either of the time-points (p-value = 0.07-1).

CONCLUSIONS

Boric acid sponge-preservation using Uriswab™ is a useful alternative to refrigeration of urine samples during transport. Reliable quantitative bacterial culture results can be obtained from canine urine up to 48 h after collection if urine is refrigerated, and for at least 24 h if urine is stored using a boric acid-containing urine transport system.

A review of the current concepts in canine urinary tract infections

Traditionally, urinary tract infections (UTIs) have been categorised as either uncomplicated or complicated in veterinary medicine, with treatment differing for the two categories. In human medicine, there is an additional category: Asymptomatic bacteriuria, which is the presence of bacteriuria without symptoms of infection. Escherichia coli (E.coli) is the most common bacterial species involved in UTIs in dogs. Clinical signs can be absent in dogs with complicated UTIs, and this has been likened to asymptomatic bacteriuria (ASB) in people and has been termed subclinical bacteriuria (SBU) with the treatment recommendations for SBU in dogs have been adapted from human recommendations. There is a shift in the current treatment of UTIs to help minimise the development of antimicrobial resistance. Routine screening of dogs with conditions that may predispose them to UTIs has been discouraged as has the treatment of SBU. This has been due to the increase in antimicrobial resistance (AMR).

How Accurate Are Veterinary Clinicians Employing Flexicult Vet for Identification and Antimicrobial Susceptibility Testing of Urinary Bacteria?

Antibiotics are frequently used for treating urinary tract infections (UTI) in dogs and cats. UTI often requires time-consuming and expensive antimicrobial susceptibility testing (AST). Alternatively, clinicians can employ Flexicult Vet, an affordable chromogenic agar with added antibiotics for in-clinic AST. We investigated how well veterinary microbiologists and clinicians, without any prior experience, employ Flexicult Vet for the identification and AST of the most common canine and feline urinary pathogenic bacteria. We prepared 47 monoculture plates containing 10 bacterial species. The test's mean accuracy was 75.1% for bacteria identification (84.6% and 68.7% for microbiologists and clinicians, respectively) and 79.2% for AST (80.7% and 78.2%). All evaluators employed Flexicult Vet with the accuracies over 90% for the distinctively colored bacteria like Escherichia coli (red), Enterococcus faecalis (turquoise), and Proteus spp. (pale brown). However, the evaluators' experience proved important in recognizing lightly colored bacteria like Staphylococcus pseudintermedius (accuracies of 82.6% and 40.3%). Misidentifications of E. faecium additionally worsened AST performance since bacterial intrinsic resistance could not be considered. Finally, only 33.3% (3/9) of methicillin-resistant S. pseudintermedius (MRSP) were correctly detected. To conclude, Flexicult Vet proved reliable for certain urinary pathogens. In contrast, light-colored bacteria (e.g., Staphylococcus), often misidentified, require a standard AST.

Prospective trial of different antimicrobial treatment durations for presumptive canine urinary tract infections

Background

Avoidance of unnecessary antimicrobial administration is a key tenet of antimicrobial stewardship; knowing the optimal duration of therapy obviates over-treatment. However, little research has been performed to establish course lengths for common canine infections. In clinical practice, antimicrobial therapy is frequently prescribed in dogs presenting lower urinary tract signs (haematuria, pollakiuria and dysuria/stranguria). The proposed length of treatment in International Consensus guidelines has decreased with each iteration, but these recommendations remain arbitrary and largely extrapolated from experience in people.

Methods

The objective of this prospective, multi-centre study is to find the shortest course duration that is non-inferior to the standard duration of 7 days of amoxicillin/clavulanate in terms of clinical outcomes for female dogs with lower urinary tract signs consistent with a urinary tract infection. An electronic data capture platform will be used by participating veterinarians working in clinical practice in the United Kingdom. Eligible dogs must be female, aged between 6 months and 10 years and have lower urinary tract signs of up to seven days’ duration. Enrolment will be offered in cases where the case clinician intends to prescribe antimicrobial therapy. Automatic pseudo-randomisation to treatment group will be based on the day of presentation (Monday-Friday); all antimicrobial courses will be completed on the Sunday after presentation generating different treatment durations. Follow-up data will be collected 1, 8 and 22–26 days after completion of the antimicrobial course to ensure effective safety netting, and to monitor short-term outcome and recurrence rates. Informed owner consent will be obtained in all cases. The study is approved by the Ethical Review Board of the University of Nottingham and has an Animal Test Certificate from the Veterinary Medicine’s Directorate.

Discussion

This study has been designed to mirror current standards of clinical management; conclusions should therefore, be widely applicable and guide practising veterinarians in their antimicrobial decision-making process. A duration-response curve will be created allowing determination of the optimal treatment duration for the management of female dogs with lower urinary tract signs. It is hoped that these results will contribute valuable information to improve future antimicrobial stewardship as part of a wider one-health perspective.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-021-02974-y.

Assessment of animal diseases caused by bacteria resistant to antimicrobials: Dogs and cats

In this opinion the antimicrobial-resistant bacteria responsible for transmissible diseases that constitute a threat to dog and cat health have been assessed. The assessment has been performed following a methodology based on information collected via an extensive literature review and expert judgement. Details of the methodology used for this assessment are explained in a separate opinion. A global state of play of antimicrobial resistant Staphylococcus pseudintermedius, Staphylococcus aureus, Staphylococcus schleiferi, Escherichia coli, Proteus mirabilis, Klebsiella spp., Enterobacter spp., Pseudomonas aeruginosa, Clostridium perfringens, Clostridioides difficile, Enterococcus faecalis and Enterococcus faecium has been provided. Among those bacteria, EFSA identified S. pseudintermedius, E. coli and P. aeruginosa with > 90% certainty as the most relevant antimicrobial resistant bacteria in the EU based on the available evidence. The animal health impact of these most relevant bacteria, as well as their eligibility for being listed and categorised within the animal health law framework will be assessed in separate scientific opinions.

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.

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.

The Complex Diseases of Staphylococcus pseudintermedius in Canines: Where to Next?

Staphylococcus pseudintermedius is a pathogenic bacterium of concern within the veterinary sector and is involved in numerous infections in canines, including topical infections such as canine pyoderma and otitis externa, as well as systemic infections within the urinary, respiratory and reproductive tract. The high prevalence of methicillin-resistant Staphylococcus pseudintermedius (MRSP) within such infections is a growing concern. Therefore, it is crucial to understand the involvement of S. pseudintermedius in canine disease pathology to gain better insight into novel treatment avenues. Here, we review the literature focused on S. pseudintermedius infection in multiple anatomic locations in dogs and the role of MRSP in treatment outcomes at these niches. Multiple novel treatment avenues for MRSP have been pioneered in recent years and these are discussed with a specific focus on vaccines and phage therapy as potential therapeutic options. Whilst both undertakings are in their infancy, phage therapy is versatile and has shown high success in both animal and human medical use. It is clear that further research is required to combat the growing problems associated with MRSP in canines.

Insects, Rodents, and Pets as Reservoirs, Vectors, and Sentinels of Antimicrobial Resistance

This paper reviews the occurrence of antimicrobial resistance (AMR) in insects, rodents, and pets. Insects (e.g., houseflies, cockroaches), rodents (rats, mice), and pets (dogs, cats) act as reservoirs of AMR for first-line and last-resort antimicrobial agents. AMR proliferates in insects, rodents, and pets, and their skin and gut systems. Subsequently, insects, rodents, and pets act as vectors that disseminate AMR to humans via direct contact, human food contamination, and horizontal gene transfer. Thus, insects, rodents, and pets might act as sentinels or bioindicators of AMR. Human health risks are discussed, including those unique to low-income countries. Current evidence on human health risks is largely inferential and based on qualitative data, but comprehensive statistics based on quantitative microbial risk assessment (QMRA) are still lacking. Hence, tracing human health risks of AMR to insects, rodents, and pets, remains a challenge. To safeguard human health, mitigation measures are proposed, based on the one-health approach. Future research should include human health risk analysis using QMRA, and the application of in-silico techniques, genomics, network analysis, and ’big data’ analytical tools to understand the role of household insects, rodents, and pets in the persistence, circulation, and health risks of AMR.

Clinical significance of Proteus mirabilis bacteriuria in dogs, risk factors and antimicrobial susceptibility

The objectives of this study were to describe the in vitro antimicrobial susceptibility and clinical significance of Proteus mirabilis in canine bacteriuria and to identify the risk factors associated with P. mirabilis urinary tract infections. This is a retrospective observational study of 48 P. mirabilis-positive canine urinary cultures. Only 22 of the 48 P. mirabilis isolates (45.8%) were non-susceptible to at least one tested antimicrobial. Most P. mirabilis isolates (98%) were susceptible to enrofloxacin, 93.7% to amoxicillin/clavulanic acid, and 85.4% to ampicillin, cephalothin, and trimethoprim-sulfamethoxazole. Five multidrug-resistant isolates were detected (10.4%). A significant increase in antimicrobial resistance was observed over the study period. Positive P. mirabilis cultures were associated with bacterial cystitis in 36 of 39 dogs (92.3%), pyelonephritis in 2 of 39 dogs (5.1%), and one dog had both bacterial cystitis and pyelonephritis (2.5%). There was no subclinical bacteriuria. Most urinary tract infections were complicated as risk factors were identified in 37 of 39 dogs (94.8%). The most commonly identified risk factors were the presence of a contaminated peri-vulvar area with urine/feces or a hypoplastic vulva. To conclude, P. mirabilis bacteriuria was associated with upper and lower urinary tract infections in this study and was found more frequently in complicated bacterial cystitis. Multidrug-resistant isolates and increased P. mirabilis antimicrobial resistance have been identified over the last 10 years, but most isolates remain susceptible to first-line antimicrobials such as amoxicillin and trimethoprim-sulfamethoxazole.

[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.

The Occurrence of Multidrug Resistant Bacteria in the Urine of Healthy Dogs and Dogs with Cystitis

Simple Summary

Antimicrobial resistance is a global health issue. The “One Health” concept describes animals and environments playing an important role in the resistance to antimicrobials. In this study, we survey healthy companion animals (dogs) as a potential source of multidrug resistant (MDR) bacteria, and compare them with dogs with cystitis. Both groups have a similar isolated genus profile and frequency of multidrug resistance. In our study, both healthy and cystitis animals were found to be carriers of MDR bacteria.

Abstract

The objectives of this study were to evaluate the occurrence of microorganisms, the antimicrobial susceptibility profile, and the presence of multidrug resistant (MDR) bacteria in the urine of clinically healthy dogs and dogs with cystitis. The urine was collected through cystocentesis. Subsequently, culture and antimicrobial susceptibility tests were performed. The isolates were classified based on their resistance profile, to evaluate the presence of MDR bacteria. Statistical analyses were performed using the chi-squared or Fisher’s exact tests. Bacterial isolates were present in 24.39% of the dogs in the control group, and 60.27% of the dogs in the cystitis group. The cystitis group was associated with a higher risk of bacterial isolates than the control group (odds ratio = 7.5; 95% confidence interval = 2.81–22.40). The main isolates were Staphylococcus spp., Escherichia coli, Proteus spp., and Enterobacter spp. in both groups. A high percentage of isolates were resistant to ampicillin in both groups. The lowest resistance presented by the isolates in both groups was to meropenem. Only the resistance to quinolones was different between the groups. The proportions of MDR isolates were 70% (7/10) and 65.91% (29/44) in the control and cystitis groups, respectively. The results showed the presence of MDR bacteria in the urine of both the healthy dogs, and the dogs with cystitis. The drug resistance was high, reinforcing the importance of establishing an effective treatment approach against urinary tract infections in pets, to minimize the spread of bacterial resistance and its impact on public health.

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%).

Pre-test probability of urinary tract infection in dogs with clinical signs of lower urinary tract disease

Clinical signs of lower urinary tract disease in dogs are characteristic but non-specific for infection. It has been hypothesized that age, sex and neuter status influences the prevalence of urinary tract infection (UTI), but the predictive value of the combined clinical presentation has not been explored in dogs. The aim of the study was to assess clinical predictors (sex/neuter status, age, dysuria/stranguria, pollakiuria, macroscopic hematuria, malodorous urine and history of recurrent UTI) for bacterial cystitis, and to develop a clinical decision rule. Data was retrieved from medical records (retrospective cases) or from standardized recording sheets (prospective cases). Bacterial cystitis was defined as significant bacteriuria on quantitative bacterial culture in dogs with compatible clinical signs of urinary tract disease. Dogs of any breed, sex and age were included. A total of 1727 microbiology records were screened and 424 samples were included in the analysis. Bacterial cystitis was confirmed in 46% of the cases. Four variables predicted bacterial cystitis: sex/neuter status, age, pollakiuria and hematuria. A score was designated to each variable and a clinical rule was constructed. This rule attained an AUC of 0.75 and had sensitivity of 83% and specificity of 55% at its optimal cut-off (score ≥2.0). A score cut-off of ≥3.0 had a positive predictive value of 70%. Several factors predicted bacterial cystitis, but the clinical rule had only modest predictive value. Other variables or point-of-care test results should be included in future research to optimize overall precision.

Pathogens isolated from clinical cases of urinary tract infection in dogs and their antibiogram

Aim:

This study aims to determine the etiology of urinary tract infection (UTI) in dogs and to develop an antibiogram of organisms isolated.

Materials and Methods:

Urine samples were collected either through catheterization or cystocentesis from 35 dogs suspected of UTI admitted to VCC, LUVAS, Hisar. Bacteria were identified on the basis of cultural characteristics in 22 samples, and all the isolates were subjected to in vitro antimicrobial sensitivity testing.

Results:

The urine samples found positive for bacteria yielded pure colony growth in 77.27% and mixed growth in 22.73% samples, respectively. Escherichia coli (29.62%) and Streptococcus spp. (29.62%) were the most prevalent microorganisms followed by Staphylococcus spp. (22.22%), Klebsiella spp. (11.11%), Pseudomonas spp. (3.7%), and Bacillus spp. (3.7%). Overall, maximum sensitivity of isolates was found toward ceftriaxone/tazobactam (88.88%) and least toward amoxicillin and cloxacillin (29.62%).

Conclusion:

E. coli and Streptococcus spp. were the most predominant bacteria isolated from UTI affected dogs. In vitro sensitivity revealed a significant proportion of bacteria to be multidrug resistant.

Effects of Diagnostic Work-Up on Medical Decision-Making for Canine Urinary Tract Infection: An Observational Study in Danish Small Animal Practices

BACKGROUND

Clinical signs of urinary tract disease in dogs often lead to prescription of antibiotics. Appropriate diagnostic work-up could optimize treatment and reduce the risk of inappropriate use of antibiotics.

HYPOTHESIS/OBJECTIVES

To describe and evaluate the impact of diagnostic work-up on decision to treat (DTT) and choice of antibiotic treatment (COT) for dogs presenting with clinical signs of urinary tract disease.

ANIMALS

One hundred and fifty-one dogs presenting to 52 Danish veterinary practices.

METHODS

Prospective, observational study. Clinical signs, diagnostic work-up, and prescriptions were recorded. Urine samples were submitted to a reference laboratory for quantitative bacterial culture (QBC) and susceptibility testing. The laboratory results were used as reference for assessing the appropriateness of DTT and COT.

RESULTS

In the majority of dogs, veterinarians performed dipstick (99%), microscopic examination of urine (80%) and bacterial culture (56%). Fifty-one percent of dogs had urinary tract infection (UTI) based on reference QBC. Appropriate DTT was made for 62% of the dogs, while 36% were over-prescribed and 2% under-prescribed. Inappropriate use of second-line agents was found in 57% of the UTI cases. Performing microscopy-but not culture-significantly impacted DTT (P = 0.039) while no difference was seen in COT (P = 0.67). The accuracy of in-house microscopy and culture were 64.5 and 77%, respectively.

CONCLUSIONS AND CLINICAL IMPORTANCE

Over-prescription of antibiotics was common among dogs with suspected UTI, regardless of the diagnostic work-up performed. Test inaccuracy under practice conditions and incoherence between diagnostic test results and decision-making both explained inappropriate and unnecessary use of antibiotics.

Antimicrobial susceptibility survey on bacterial agents of canine and feline urinary tract infections: Weight of the empirical treatment

OBJECTIVES

This work characterised the antimicrobial susceptibility of uropathogens isolated from empirically treated dogs and cats. Within-household transmission of uropathogens can involve humans and companion animals. Knowledge on the prevalence and susceptibility pattern of isolates from canine and feline urine samples and the impact of prior antimicrobial treatment is important to prevent the dissemination of antimicrobial resistance.

METHODS

A retrospective study was conducted selecting antibiotic-treated companion animals. Urine samples were collected by cystocentesis and were submitted to an Italian diagnostic laboratory over a 2-year period (2013-2015). The antimicrobial susceptibility of the isolates was analysed both using Clinical and Laboratory Standards Institute (CLSI) guidelines and a formula to help select rational antimicrobial therapy.

RESULTS

Gram-negative bacteria were clearly prevalent. Gentamicin had the highest impact factors. Amoxicillin/clavulanic acid and doxycycline appeared to be the most effective compounds against Gram-positive infections, whilst marbofloxacin may be a useful option against Gram-negative urinary tract infections (UTIs) as well as doxycycline and trimethoprim/sulfamethoxazole in cats and dogs, respectively. Consulting published studies, a comparable overall trend regarding bacterial species incriminated in canine and feline UTIs and their susceptibilities seems likely, despite different circumstances where the studies were conducted.

CONCLUSIONS

Companion animals are potential reservoirs of drug-resistant uropathogens. Judicious use of antibiotics is necessary to maintain the efficacy of antimicrobials in human and veterinary medicine. Antimicrobial susceptibility monitoring programmes are therefore essential to facilitate the choice of antimicrobial agent that is most likely to be effective, particularly in cases of prior antimicrobial treatment.

Uropathogenic Escherichia coli in the Urine Samples of Iranian Dogs: Antimicrobial Resistance Pattern and Distribution of Antibiotic Resistance Genes

Resistant uropathogenic Escherichia coli is the most common cause of urinary tract infections in dogs. The present research was done to study the prevalence rate and antimicrobial resistance properties of UPEC strains isolated from healthy dogs and those which suffered from UTIs. Four-hundred and fifty urine samples were collected and cultured. E. coli-positive strains were subjected to disk diffusion and PCR methods. Two-hundred out of 450 urine samples (44.4%) were positive for E. coli. Prevalence of E. coli in healthy and infected dogs was 28% and 65%, respectively. Female had the higher prevalence of E. coli (P = 0.039). Marked seasonality was also observed (P = 0.024). UPEC strains had the highest levels of resistance against gentamicin (95%), ampicillin (85%), amikacin (70%), amoxicillin (65%), and sulfamethoxazole-trimethoprim (65%). We found that 21.50% of UPEC strains had simultaneously resistance against more than 10 antibiotics. Aac(3)-IV (77%), CITM (52.5%), tetA (46.5%), and sul1 (40%) were the most commonly detected antibiotic resistance genes. Findings showed considerable levels of antimicrobial resistance among UPEC strains of Iranian dogs. Rapid identification of infected dogs and their treatment based on the results of disk diffusion can control the risk of UPEC strains.

Clinicopathologic and Microbiologic Findings Associated with Emphysematous Cystitis in 27 Dogs

This is a retrospective case series of 27 dogs with emphysematous cystitis. Medical records from two veterinary teaching hospitals from 1992 to 2014 were reviewed. The aims of the study were to determine imaging findings, common underlying disease processes, and prevalent bacterial species and their antimicrobial susceptibility patterns in dogs with emphysematous cystitis. The most common lower urinary tract sign was hematuria. Gas was detected in the wall and lumen of the urinary bladder in 14 of 27 dogs (51.9%), in only the wall of the bladder in 9 of 27 dogs (33%), and in only the lumen of the bladder in 4 of 27 dogs (14.8%). Comorbid diseases were identified in all but one case. The most common comorbid disease processes were diabetes mellitus in 33% of dogs, neurologic disease in 26% of dogs, and adrenal disease in 19% of dogs. Bacterial isolates included Escherichia coli, Enterococcus spp., Klebsiella pneumoniae, Proteus mirabilis, Streptococcus spp., and Actinomyces spp. Enterococcus spp. were always isolated in mixed infections with gas-producing bacterial species. During the period of study, most isolates were predicted to be susceptible to beta-lactam drugs, but updated veterinary breakpoints suggest that fluoroquinolones or trimethoprim-sulfamethoxazole would be more appropriate choices for empiric therapy.

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.

Antimicrobial Susceptibility Monitoring of Bacterial Pathogens Isolated from Urinary Tract Infections in Dogs and Cats Across Europe: ComPath Results

ComPath is a pan-European antimicrobial surveillance program collecting bacterial pathogens from dogs and cats not recently exposed to antimicrobials. We present minimum inhibitory concentration data obtained using Clinical and Laboratory Standards Institute methodology for 616 urinary tract infection (UTI) isolates collected between 2008 and 2010. In both dogs and cats, the most common pathogen was Escherichia coli (59.8% and 46.7%, respectively). Antimicrobial activity against E. coli in dogs and cats was similar with fluoroquinolone and trimethoprim/sulfamethoxazole susceptibility >90%. Ampicillin susceptibility was ∼80%. Staphylococcus intermedius Group isolates from dogs (67/437, 15.3%) had high antimicrobial susceptibility (>90%) toward beta-lactams, fluoroquinolones, and trimethoprim/sulfamethoxazole. Four canine isolates (6%) were oxacillin resistant, and harbored mecA. Proteus mirabilis from dogs (48/437, 11.0%) had high antimicrobial susceptibility (∼90%) to amoxicillin/clavulanic acid, enrofloxacin, and marbofloxacin and slightly lower susceptibility (∼80-85%) to ampicillin and orbifloxacin. Streptococcus canis isolates (35/437, 8.0%) from dogs were all susceptible to ampicillin and amoxicillin/clavulanic acid and >90% susceptible to marbofloxacin. Although resistance was not observed, high intermediate susceptibility was seen for both enrofloxacin (28.6%) and orbifloxacin (85.7%). Overall, antimicrobial in vitro activity appears to be high in UTI pathogens from dogs and cats with low multidrug resistance, although a lack of specific dog and cat breakpoints for important antimicrobials such as cefovecin, cephalexin, and ibafloxacin prevents analysis of susceptibility for these agents.

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.

Evidence of household transfer of ESBL-/pAmpC-producing Enterobacteriaceae between humans and dogs - a pilot study

Background

Extended-spectrum cephalosporin-resistant Enterobacteriaceae (ESCRE) are an increasing healthcare problem in both human and veterinary medicine. The spread of ESCRE is complex with multiple reservoirs and different transmission routes. The aim of this study was to investigate if ESCRE carriage in dogs is more prevalent in households with a known human carrier, compared to households where humans are known to be negative for ESCRE. Identical ESCRE strains in humans and dogs of the same household would suggest a possible spread between humans and dogs.

Methods

Twenty-two dog owners with a positive rectal culture for ESCRE each collected a rectal sample from their dog. In addition, a control group of 29 healthy dog owners with a documented negative rectal culture for ESCRE each sampled their household dog. Samples were cultivated for ESCRE using selective methods. In households where both humans and dogs carried ESCRE, isolates were further analysed for antimicrobial susceptibility by disc diffusion or microdilution and for genotype and genetic relatedness using molecular methods.

Results

In 2 of 22 households studied, identical ESCRE strains with respect to bacterial species, antibiogram, genotype, and MLVA type were found in humans and dogs. The ESCRE found in the two households were ESBL-producing E. coli with the resistance gene bla_CTX-M-27 and AmpC-producing E. coli with bla_CMY-2, bla_TEM-1. ESCRE were not found in dogs in the control group.

Conclusions

In households where humans are carrying ESCRE, identical strains were to a limited extent found also in household dogs, indicating a transfer between humans and dogs. In contrast, ESCRE were not found in dogs in households without human carriers.

Acute cholecystitis associated with infection of Enterobacteriaceae from gut microbiota

Acute cholecystitis (AC) is one of the most common surgical diseases. Bacterial infection accounts for 50% to 85% of the disease's onset. Since there is a close relationship between the biliary system and the gut, the aims of this study were to characterize and determine the influence of gut microbiota on AC, to detect the pathogenic microorganism in the biliary system, and to explore the relationship between the gut and bile microbiota of patients with AC. A total of 185 713 high-quality sequence reads were generated from the faecal samples of 15 patients and 13 healthy controls by 16S rRNA gene pyrosequencing. Patients' samples were significantly enriched in Akkermansia, Enterobacter and Escherichia/Shigella group. The healthy controls, however, showed significant enrichment of Clostridiales, Coprococcus, Coprobacillaceae, Paraprevotella, Turicibacter and TM7-3 in their faecal samples. Escherichia coli was the main biliary pathogenic microorganism, among others such as Klebsiella spp., Clostridium perfringens, Citrobacter freundii and Enterobacter cloacae in the bile of the patients. Additionally, the amount of bile endotoxin significantly correlated with the number of Enterobacteriaceae, especially E. coli. Our data indicate that Enterobacteriaceae might play essential role in the pathogenesis and/or progress of AC. This was verified in an in vivo model using a pathogenic E. coli isolated from one of the patients in guinea pigs and observed marked gallbladder inflammation and morphologic changes. This study thus provides insight which could be useful for the prevention, diagnosis and treatment of AC and related diseases by controlling the growth of Enterobacteriaceae to alleviate the infection.