Diagnosis of urinary tract infections

Mitigating antimicrobial resistance, an approach to stewardship in canine urinary tract infection

Urinary tract infection (UTI) caused by antimicrobial resistant bacteria is common in dogs leading to serious health impact in pet animal as well as on human health. Understanding the prevalent uropathogens and their drug susceptibility is essential for limiting the antimicrobial resistance through implementation of stewardship policies. In view of this, present study was envisaged to determine the prevalent bacterial uropathogens and their antibiogram from clinical cases of canine UTI. Urine samples were collected from 35 dogs presented with clinical signs of UTI and a total of 27 bacterial isolates were recovered. Among that Escherichia coli was the most predominant isolate followed by Klebsiella aerogenes, Staphylococcus aureus, Proteus mirabilis, Enterococcus sp. and Citrobacter freundii. All isolates were found resistant to one or more 1st line antibiotics recommended by consensus guidelines and 70% of total isolates showed multidrug resistance. Additionally, this study evaluated the weightage of empirical therapy as per the consensus guidelines over antimicrobial susceptibility test guided treatment. Dogs with uncomplicated UTI were selected and categorized into three different groups (n = 6). Group 1 was treated with common empirical choice amoxycillin-clavulanic acid and dogs showed susceptible to ciprofloxacin were kept in Group 2 and treated with ciprofloxacin along with urinary alkalizer disodium hydrogen citrate. Nitrofurantoin susceptible cases were kept in Group 3 and treated with a combination of nitrofurantoin and urinary acidifier ammonium chloride. Therapeutic outcome was evaluated and success rate was higher in Group 2 and 3 than Group 1 suggested that selection of antibiotics with the use of local or institutional antibiogram data is more considerate than acknowledged international guidelines in the existing situation.

Diagnostic ultrasonography and antimicrobial resistance of different pathogens associated with canine and feline lower urinary tract disorders

There is a significant issue concerning the dissemination of antimicrobial-resistant bacteria within companion animals. Urinary tract infections (UTIs) are a common problem in veterinary medicine for which empirical antibiotics are utilized. This study aimed to investigate the antimicrobial resistance of different uropathogens associated with UTIs in canine and feline cases. A total of 146 dogs and 162 cats suffered from lower urinary tract disorders were subjected to ultrasonographic and microbiological examination. Cystitis, urinary sediment, and cystic calculi are the most common ultrasonographic abnormalities associated with bacterial UTIs. Bacterial UTIs were obtained in 36.98 % and 25.92 % of cases in dogs and cats, respectively. A low rate of mixed infection was detected in canine cases (3.7 %). E. coli was the most prevalent pathogen isolated from 46.4 % and 66.7 % of canine and feline isolates, respectively followed by Proteus spp. in canine isolates (16.1 %) and Klebsiella spp. in feline isolates (14.3 %). Staphylococcus spp. was isolated from canine cases only with the detection of methicillin-resistant Staphylococcus pseudintermedius (MRSP) strains at 3.6 %. The majority of the isolated strains were resistant to various antibiotic classes, particularly β-lactams. All gram-negative bacteria were susceptible to amikacin, whereas gram-positive strains exhibited 100 % sensitivity to nitrofurantoin and linezolid. Different bacterial species displayed low resistance to carbapenems and fluoroquinolones. Multi-drug resistance was reported in canine and feline strains at 64.3 % and 54.8 %, respectively. These findings prove the crucial necessity to restrict antibiotic consumption depending on urine culture and antibiotic sensitivity tests.

Longitudinal examination of urine pH, specific gravity, protein, culture, and antimicrobial resistance profiles in healthy dogs

BACKGROUND

Urine is routinely evaluated in dogs to assess health. Reference ranges for many urine properties are well established, but the scope of variation in these properties over time within healthy dogs is not well characterized.

OBJECTIVES

Longitudinally characterize urine properties in healthy dogs over 3 months.

ANIMALS

Fourteen healthy client-owned dogs.

METHODS

In this prospective study, dogs were evaluated for health; then, mid-stream free-catch urine was collected from each dog at 12 timepoints over 3 months. Urine pH, urine specific gravity (USG), protein, cultures, and antimicrobial resistance profiles were assessed at each timepoint.

RESULTS

Urine pH varied within and between dogs over time (Friedman's test: within P = .03; between P < .005). However, USG, protein, and bacterial diversity of urine were consistent within dogs over time, and only varied between dogs (Kruskal-Wallis: between all P < .005). Antimicrobial resistant isolates were identified in 12 out of 14 dogs with 34 of 48 of the isolates demonstrating resistance to amoxicillin.

CONCLUSIONS AND CLINICAL IMPORTANCE

Urine pH should be assessed at multiple timepoints via pH meter before making clinical decisions. Mid-stream free-catch urine with high concentrations of bacteria (>105  CFU/mL) should not be considered the only indicator of urinary tract infection. Bacterial isolates from dogs in this study had widespread resistance to amoxicillin/oxacillin underscoring the need for antimicrobial stewardship.

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.

Bacterial Isolates from Urinary Tract Infection in Dogs and Cats in Portugal, and Their Antibiotic Susceptibility Pattern: A Retrospective Study of 5 Years (2017-2021)

There are growing concerns regarding the rise of antimicrobial-resistant bacteria in companion animals. This study aimed to bring new insights into the current scenario of Portugal's antimicrobial resistance bacteria isolated from companion animals with urinary tract infections and is the first to be performed during a long period on a large scale. Of a total of 17472 urine samples analyzed, 12,166 (69.6%) (CI 12,200-12,200) were negative for bacterial growth, and 5306 (30.4%) (95% CI 5310-5310) had bacterial growth. Of the culture-positive samples, 5224 (96.6%) (95% CI 5220-5220) were pure cultures and 82 (3.2%) (95% CI 81.9-82.1) had mixed growth. Escherichia coli was the most frequently isolated bacteria (n=2360, 44.5%) (95% CI 2360-2360), followed by Proteus mirabilis (n=585, 11%) (95% CI 583-583), Enterococcus faecium (n=277, 5.2%) (95% CI 277-277) and Staphylococcus pseudintermedius (n=226, 4.3%) (95% CI 226-226). The overall susceptibility rates were low for erythromycin (45.3%) and clindamycin (51.3%), and high for aminoglycosides (96.3%), carbapenems (92.4%), trimethoprim-sulfamethoxazole (81.2%), and quinolones (79.9%). E. coli also showed considerable resistance to amoxicillin-clavulanic acid. The rates of multidrug-resistant bacteria are still high compared to the northern countries of Europe. This study's findings show the emergence of antibiotic resistance in the antibiotic agents commonly used in the treatment of UTIs in dogs and cats in Portugal.

Urinary Cytology: Potential Role in Canine Urinary Tract Infections

The diagnosis of urinary tract infections (UTIs) requires a concomitant evaluation of clinical signs and urine culture, which is of fundamental to start an appropriate antibiotic treatment. Several factors, such as subclinical bacteriuria or pre-analytical errors, may make the interpretation of urine culture difficult. The aim of the study was to evaluate the association between the finding of neutrophils and bacteria in unstained and stained canine urine sediment and the presence of clinical signs and positive urine culture. Urine samples from 35 dogs with clinical signs of UTI and 55 asymptomatic dogs with risk factors for UTI were prospectively collected by cystocentesis, divided into three aliquots, and submitted for: (1) physical and chemical Dipstick analysis and unstained urinary sediment (casts, crystals, bacteria, leucocytes, cells, parasites); (2) stained urinary sediment (extra/intracellular bacteria, degenerated and non-degenerated neutrophils); (3) qualitative and quantitative urine culture and antimicrobial sensitivity-test. The association between unstained and stained findings of urinary sediment and urine culture was tested. Sensibility, specificity, and positive/negative predictive values in diagnosing positive urine cultures of bacteria at unstained and stained evaluation were compared. Both wet-mount bacteriuria and the cytological presence of intracellular and extracellular bacteria, neutrophils, and degenerated neutrophils were successively associated with positive urine culture (p < 0.001). The presence of intracellular bacteria was the only independent predictor of positive urine culture. Total bacterial count did not differ significantly between symptomatic and asymptomatic dogs. Detection of extracellular and intracellular bacteriuria at stained urinary sediment significantly improved the sensibility of predicting positive urine culture. Cytologic evaluation of urinary sediment may be helpful in detecting signs of active inflammation, thus enhancing the clinical relevance of a positive urine culture.

Accuracy of the IDEXX SediVue Dx analyzer for quantifying RBC and WBC indices in the urine sediments of cats and dogs compared with manual microscopic evaluations

BACKGROUND

The IDEXX SediVue Dx (SediVue) is an automated, in-clinic urine sediment analyzer for veterinary patients. The bias between the results from manual microscopy and the SediVue is currently unknown.

OBJECTIVES

To assess the diagnostic accuracy of the SediVue, we aimed to determine the bias between the SediVue (index test) and manual microscopy (reference standard) for the quantification of RBCs and WBCs in urine.

METHODS

Urine remnant samples were collected from cats and dogs that contained RBCs (n = 462) and WBCs (n = 510). Retrospective analysis of results from urine sediment examinations using both manual microscopy (using a KOVA and DeciSlide system) and the SediVue (1.0.1.3) was performed. Bias was determined with Bland-Altman plots. SediVue-captured images from high-bias samples were reviewed, and biases were compared.

RESULTS

The median bias for semi-quantitative RBC and WBC counts was determined for RBC and WBC counts. The cutoffs were RBC ≤ 5/HPF, 0.3; RBC 5.1-10/HPF, 10.1; RBC 10.1-20/HPF, 10.6; and RBC > 20/HPF, 28.93; WBC ≤ 5/HPF, 0.1; WBC 5.1-10/HPF, 2.2; WBC 10.1-20/HPF, 9.4; and WBC > 20/HPF, 26.6. High bias between the methods was identified in 98 samples (21.0%) with RBCs and 77 samples (15.7%) with WBCs. Reviewer-based enumeration of the SediVue-captured images decreased the percentage of samples with high bias to 17.3% for RBCs and to 11.4% for WBCs.

CONCLUSIONS

Bias in the RBC and WBC counts between manual microscopy and the SediVue was unlikely to impact clinical interpretations in a majority of cases. Although reviewer enumeration of SediVue-captured images reduced observed bias, inherent differences between methodologies appeared to have a larger impact on the bias.

Bacterial urinary tract infection and subclinical bacteriuria in dogs receiving antineoplastic chemotherapy

Background

Immunosuppressive treatment with glucocorticoids and cyclosporine increases the risk for positive urine cultures (PUCs) in dogs.

Objective

To investigate the prevalence and incidence of PUC in dogs diagnosed with cancer and treated with antineoplastic chemotherapy while distinguishing between subclinical bacteriuria (SB) and urinary tract infection (UTI).

Animals

Forty‐six client‐owned dogs with nonurogenital cancer treated with antineoplastic chemotherapy.

Methods

Prospective observational longitudinal clinical study. Dogs in which a urine culture was performed before the start of and at least once during antineoplastic chemotherapy were included. A McNemar's test was used to investigate if the prevalence of PUC increased during antineoplastic chemotherapy. Positive urine cultures were categorized into SB and UTI and multiple PUCs from the same dog and category were grouped together as 1 episode of PUC.

Results

Urine culture was positive in 21/185 urine samples in 8/46 dogs. Antineoplastic chemotherapy did not influence the prevalence of PUC (P = 1.00), which was 11% (5/46 dogs; 95% confidence interval: 5‐23%) before the start of and 13% (6/46 dogs; 95% confidence interval: 6‐26%) during antineoplastic chemotherapy. Eight dogs had 10 episodes of PUC; 7/10 episodes were classified as SB, and in 3/10 episodes UTI (chronic prostatitis, prostatic abscess, and emphysematous cystitis) was diagnosed. Escherichia coli was the most common pathogen, isolated in 9/10 episodes.

Conclusions and Clinical Importance

We did not find evidence that antineoplastic chemotherapy is a major predisposing factor for the development of PUC. Most dogs with PUC had SB.

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.

Antibiotic Stewardship for Canine and Feline Acute Urinary Tract Infection: An Observational Study in a Small Animal Hospital in Northwest Italy

Antimicrobial stewardship programs (ASPs) have been suggested to reduce antimicrobial resistance phenomena in veterinary medicine, as antibiotics are commonly used without microbiological confirmation. The aim of the present study is to design a specific working flow for a tailored antimicrobial treatment in the case of canine and feline urinary tract infections (UTIs). Urine samples were collected by cystocentesis from 16 dogs and 12 cats presenting acute signs of UTI. The therapy was decided according to the minimal inhibitory concentration, and it was possible to monitor 14 dogs and 11 cats. Rescue therapy (amoxicillin and clavulanic acid) was included in emergency cases. Escherichia coli, Proteus mirabilis, and Streptococcus canis were isolated in dogs, and Escherichia coli, Staphylococcus pseudintermedius, and Staphylococcus aureus were isolated in cats. No multidrug-resistant strains were detected, but all Staphylococci were methicillin resistant. Only one cat received rescue therapy, and only one dog was recruited. Dogs were treated with tetracycline (1/14), fluoroquinolones (6/14), beta-lactams (6/14), and gentamicin (1/14), while cats received fluoroquinolones (3/11), nitrofurans (1/11), clindamycin (1/11), and beta-lactams (6/11). The success rate was very high. Our findings are interesting because this is the first ASP in Italy, and it may be used as a model to develop ASPs for other pathologies.

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.

Development of a method for creating antibiograms for use in companion animal private practices

OBJECTIVE

To identify a method for developing antibiograms for use in companion animal private practices (PPs).

SAMPLES

Reports (n = 532) of aerobic bacterial culture and antimicrobial susceptibility testing performed between January 1, 2018, and December 31, 2018, at 11 PPs and 1 academic primary care practice (APCP).

PROCEDURES

Data extracted from reports included patient identification number, laboratory accession number, patient signalment, collection method, body site, and results of bacterial culture and antimicrobial susceptibility testing. A custom antibiogram was then constructed with the help of commonly available software by adapting methods used by human hospitals. Susceptibility patterns of bacteria isolated by PPs and the APCP were compared to identify challenges associated with collating data from multiple laboratories.

RESULTS

4 bacterial species (Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, and Staphylococcus pseudintermedius) and 3 bacterial groups (Enterobacteriaceae, Enterococcus spp, and coagulase-positive Staphylococcus spp) met the minimum requirement of ≥ 15 isolates for construction of an antibiogram. For urine samples, 3 bacterial species and 2 bacterial groups met the minimum requirement of ≥ 10 isolates. For samples from skin, 2 bacterial species and 2 bacterial groups met the minimum requirement of ≥ 10 isolates. Patient signalment, sample source, and distribution of bacterial isolates were similar between PP and APCP patients.

CONCLUSIONS AND CLINICAL RELEVANCE

Results demonstrated that it was feasible to adapt existing guidelines for developing antibiograms in human medicine to the veterinary outpatient setting. Use of antibiograms could aid in empirical antimicrobial drug selection in a manner that supports antimicrobial stewardship principles.

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.

[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.

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.

Comparison of immediate versus delayed streak plate inoculation on urine bacterial culture and susceptibility testing in dogs and cats

BACKGROUND

Quantitative bacterial culture and susceptibility testing is the gold standard diagnostic for determining bacterial urinary tract infection. Transport of samples to external reference laboratories is common practice in veterinary medicine.

OBJECTIVE

To compare bacterial culture and susceptibility results from clinical urine samples when streak plate inoculation is performed immediately after sample collection versus after transport to a reference laboratory. To determine the clinical implications of discrepant culture results.

ANIMALS

One hundred and ninety-four canine and 45 feline urine samples that were submitted for urinalysis and urine culture and susceptibility testing.

METHODS

This was a prospective, cross-sectional study. Streak plate inoculations were performed on urine samples immediately after collection and also after transport to a reference laboratory. Samples were stored in plain sterile tubes and refrigerated up to 24 hours before transport. Culture results were compared, and discordant results were evaluated for clinical relevance. Signalment, comorbidities, lower urinary tract signs, and antimicrobial history were recorded.

RESULTS

Kappa coefficient for agreement between plating methods was 0.884. Twenty-two (71%) of 31 discrepant results were determined to have no clinical impact. Though 35% of clean midstream samples had discrepant culture results, only 8% of these had clinical impact. Conversely, 8.6% from cystocentesis were discrepant, but 41% of these had clinical impact.

CONCLUSIONS AND CLINICAL IMPORTANCE

Provided urine samples are stored and transported appropriately, the immediate preplating of urine for culture and susceptibility testing is unnecessary in the majority of cases. Despite more discrepancies in plating methods for midstream samples, the minority were of clinical importance.

Urinary tract infection and subclinical bacteriuria in cats: A clinical update

PRACTICAL RELEVANCE

Urinary tract infection (UTI) is an important cause of feline lower urinary tract disease (FLUTD), particularly in female cats older than 10 years of age. In addition to cats with typical clinical signs of FLUTD or upper UTI, many cats have subclinical bacteriuria, but the clinical relevance of this is currently uncertain. UTIs are one of the most important indications for antimicrobial use in veterinary medicine and contribute to the development of antimicrobial resistance. Adherence to treatment guidelines and confinement to a few first-line antimicrobial agents is imperative to avoid further deterioration of the antimicrobial resistance situation. The decision to treat with antimicrobials should be based on the presence of clinical signs, and/or concurrent diseases, and the results of urine culture and susceptibility testing.

CLINICAL CHALLENGES

Distinguishing between cats with bacterial cystitis, and those with idiopathic cystitis and concurrent clinical or subclinical bacteriuria, is challenging, as clinical signs and urinalysis results may be identical. Optimal treatment of subclinical bacteriuria requires clarification as there is currently no evidence that demonstrates a beneficial effect of routine treatment. Management of recurrent UTIs remains a challenge as evidence for most alternatives used for prevention in cats is mainly anecdotal, and no preventive treatment modality is currently recommended.

EVIDENCE BASE

This review draws on an extensive literature base in veterinary and human medicine, including the recently updated guidelines of the International Society for Companion Animal Infectious Diseases for the diagnosis and management of bacterial urinary tract infections in dogs and cats. Where published evidence is lacking, the authors describe their own approach; notably, for the bacteriuric cat with chronic kidney disease.

Prevalence of bacteria and changes in trends in antimicrobial resistance of Escherichia coli isolated from positive canine urinary samples from an Australian referral hospital over a 5-year period (2013-2017)

Lower urinary tract disease is common in dogs with approximately 14% developing a bacterial lower urinary tract infection (UTI) during their lifetime. Empirical antimicrobials are often prescribed while waiting urine culture and susceptibility results. Regional knowledge of bacterial prevalence and antimicrobial resistance patterns aids veterinarians in antimicrobial choice. This study aimed to identify the prevalence of uropathogens in canine urine tract isolates and to assess for changes in antimicrobial resistance of Escherichia coli (E. coli) over a 5-year study period at a large multidisciplinary private referral hospital in Australia (January 2013-December 2017). The proportion of resistant isolates was compared across 5 years (Fisher's exact test and Cochran Armitage test for trend) for select antimicrobials towards E. coli. A total of 246 positive urine cultures were included. E. coli was the most prevalent uropathogen at 64%, followed by Proteus sp., Staphylococcus sp. and Enterococcus sp., respectively (9%, 8% and 7%). E. coli was most commonly resistant to amoxicillin at 41%. There was no statistically significant difference, nor trend, in resistance of E. coli isolates towards the selected antimicrobials over the 5 years. Resistance towards trimethoprim-sulfonamide was lower at 15%. This information will aid local veterinarians in selecting empirical antimicrobials pending culture results for the treatment of UTIs in dogs.

Novel Noninvasive Diagnostics

Molecular diagnostics have revolutionized human oncology to allow early detection, targeted therapy, monitoring throughout treatment, and evidence of recurrence. By identifying genetic signatures associated with cancers, liquid biopsy techniques have been developed to diagnose and monitor cancer in noninvasive or minimally invasive ways. These techniques offer new opportunities for improving cancer screening, diagnosis, and monitoring the impact of therapy on the patients over time. Liquid biopsy also drives drug development programs. Similar diagnostics hold promise for comparable results in the veterinary field. Several noninvasive/minimally invasive techniques have been described in veterinary medicine that could be referred to as liquid biopsy.

Increase in antimicrobial resistance and emergence of major international high-risk clonal lineages in dogs and cats with urinary tract infection: 16 year retrospective study

Objectives

To evaluate temporal trends in antimicrobial resistance, over 16 years, in bacteria isolated from dogs and cats with urinary tract infection (UTI) and the clonal lineages of bacteria harbouring critical antimicrobial resistance mechanisms.

Methods

Antimicrobial susceptibility testing was conducted for 948 bacteria isolated from dogs and cats with UTI (1999-2014). Resistance mechanisms were detected by PCR, namely ESBL/AmpC in third-generation cephalosporin (3GC)-resistant Escherichia coli and Proteus mirabilis, mecA in methicillin-resistant staphylococci, and aac(6')-Ieaph(2″)-Ia and aph(2″)-1d in high-level gentamicin-resistant (HLGR) enterococci. Resistant bacteria were typed by MLST, and temporal trends in E. coli and Enterobacteriaceae antimicrobial resistance were determined by logistic regression.

Results

Enterobacteriaceae had a significant temporal increase in resistance to amoxicillin/clavulanate, 3GCs, trimethoprim/sulfamethoxazole, fluoroquinolones, gentamicin and tetracycline (P < 0.001). An increase in MDR was also detected (P < 0.0001). 3GC resistance was mainly caused by the presence of blaCTX-M-15 and blaCMY-2 in E. coli and the presence of blaCMY-2 in P. mirabilis. Two major 3GC-resistant E. coli clonal lineages were detected: O25b:H4-B2-ST131 and ST648. The mecA gene was detected in 9.2% (n = 11/119) of Staphylococcus spp., including MRSA clonal complex (CC) 5 (n = 2) and methicillin-resistant Staphylococcus epidermidis CC5 (n = 4). A temporal increase in MDR methicillin-resistant Staphylococcus pseudintermedius was detected (P = 0.0069). Some ampicillin-resistant and/or HLGR Enterococcus spp. were found to belong to hospital-adapted CCs, namely Enterococcus faecalis ST6-CC6 (n = 1) and Enterococcus faecium CC17 (n = 8).

Conclusions

The temporal increase in antimicrobial resistance and in MDR bacteria causing UTI in dogs and cats creates important therapeutic limitations in veterinary medicine. Furthermore, the detection of MDR high-risk clonal lineages raises public health concerns since companion animals with UTI may contribute to the spread of such bacteria.

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.

The Effect of Urine Concentration and pH on the Growth of Escherichia Coli in Canine Urine In Vitro

Background

Lower urinary tract infections are common in dogs, and Escherichia coli is the most common bacterial pathogen isolated. The literature has conflicting evidence regarding the inhibitory effects of urine concentration and pH on E. coli growth.

Hypothesis/Objectives

To determine the effect of different pH and urine concentrations on E. coli growth in vitro.

Animals

Voided urine samples from 10 apparently healthy spayed female dogs were used.

Methods

A matrix of 9 urine specific gravity (USG; 1.010, 1.020, and 1.030) and pH (5.5, 7.0, and 8.5) combinations was prepared by diluting and titrating filtered voided urine samples. Three E. coli isolates were obtained from urine of female dogs with signs of lower urinary tract infection and cultured at different urine pH and USG combinations in wells of a microtiter plate. The number of E. coli colony‐forming units (CFU) per mL of urine was calculated after aerobic incubation of the urine at 37°C for 18 hours, and statistically compared.

Results

Significant differences were identified in the mean log CFU/mL among different combinations of pH and USG. The lowest log CFU/mL were observed in alkaline concentrated urine (pH 8.5 and USG 1.030).

Conclusions and Clinical Importance

Escherichia coli in vitro growth was higher in neutral to acidic and diluted urine compared to alkaline and concentrated urine. The impact of non‐alkalizing diluting diets on the incidence of E. coli lower urinary tract infections should be further explored.

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.

Pyelonephritis in Dogs: Retrospective Study of 47 Histologically Diagnosed Cases (2005-2015)

Background

The clinicopathologic aspects of pyelonephritis have not been reported in companion animals.

Hypothesis/Objectives

To evaluate the prevalence of pyelonephritis diagnosed in dogs in a academic referral population, describe the clinical signs and the diagnostic test results in dogs with pyelonephritis, and identify concurrent disorders in order to determine potential risk factors for pyelonephritis.

Animals

Forty‐seven dogs with a histopathologic diagnosis of pyelonephritis from the teaching hospitals of three Canadian veterinary colleges.

Methods

Retrospective case series. Review of medical records and renal histologic sections.

Results

Pyelonephritis was diagnosed in 0.4–1.3% of the cases at necropsy. Clinical signs included anorexia or inappetence (n = 27, 57%), lethargy (n = 24, 51%), vomiting (n = 17, 36%), and dehydration (n = 12, 25%). Thirty‐five dogs (75%) had concomitant disease(s). Escherichia coli was the most common pathogen isolated (37%). Pyelonephritis was classified as acute (n = 12, 26%), subacute (n = 9, 19%), and chronic (n = 26, 55%) disease; and mild (n = 7, 15%), moderate (n = 11, 24%), and severe (n = 28, 61%). Fever was significantly associated with histopathologically subacute pyelonephritis (P = 0.01).

Conclusions

In referral hospitals, pyelonephritis has a very low prevalence at necropsy. Nonspecific clinical presentation, concomitant diseases, and high variability in the diagnostic tests results make the antemortem diagnosis of pyelonephritis challenging. Neither the histopathologic stage nor the severity of the pyelonephritis was associated with fever, lumbar pain, or signs of a urinary tract infection (ie, lower urinary tract infection, upper urinary tract infection, or both) except for subacute pyelonephritis which was associated with fever.

Effects of processing delay, temperature, and transport tube type on results of quantitative bacterial culture of canine urine

OBJECTIVE

To determine the impact of processing delay, temperature, and transport tube type on results of quantitative bacterial culture (QBC) of canine urine.

DESIGN

Diagnostic test evaluation.

SAMPLE

60 mL of pooled urine from 4 dogs, divided into six 10-mL aliquots.

PROCEDURES

Urine aliquots were spiked with bacteria from 1 of 6 independent Escherichia coli cultures to achieve a target bacterial concentration of 10(5) CFUs/mL. One milliliter from each aliquot was transferred into 5 silicone-coated clot tubes (SCTs) and 5 urine transport tubes (UTTs). Samples were stored at 4°C (39°F) and 25°C (77°F) for 0, 8, and 24 hours, and then standard QBCs were performed.

RESULTS

Median bacterial concentration for urine samples stored in a UTT for 24 hours at 4°C was lower than that for samples stored in an SCT under the same conditions. Conversely, a substantial decrease in median bacterial concentration was identified for samples stored for 24 hours in an SCT at 25°C, compared with the median concentration for samples stored in a UTT under the same conditions. Median bacterial concentration in samples stored in an SCT at 25°C for 24 hours (275 CFUs/mL) was less than the cutoff typically used to define clinically important bacteriuria by use of urine samples obtained via cystocentesis (ie, > 1,000 CFUs/mL).

CONCLUSIONS AND CLINICAL RELEVANCE

Canine urine samples submitted for immediate QBC should be transported in plain sterile tubes such as SCTs. When prolonged (24-hour) storage at room temperature is anticipated, urine samples should be transported in UTTs.

Evaluation of different sampling methods and criteria for diagnosing canine urinary tract infection by quantitative bacterial culture

The use of voided urine specimens for bacteriological culture in dogs is discouraged because contamination from external genitalia could lead to misinterpretation of laboratory results. Quantitative culturing and defining significant bacteriuria could increase the usefulness of voided specimens. However, limited evidence exists for the cut-offs currently recommended. The aim of this study was to evaluate the accuracy of current veterinary cut-off values for significant bacteriuria in voided canine urine. A secondary aim was to investigate if accuracy improved when applying qualitative criteria used in humans. Paired urine specimens were collected by both cystocentesis and voiding, and quantitative bacteriological cultures were performed within the same day. Cystocentesis was used as the reference standard with a cut-off for significant bacteriuria of ≥1000 colony forming units (CFU)/mL. Voided specimens were compared to cystocentesis using: (1) the veterinary cut-off of ≥100,000 CFU/mL; and (2) various cut-offs depending on qualitative criteria (sex, clinical signs and complicating factors), adapted from human guidelines. Ninety-four dogs with suspected urinary tract infection (UTI) were included for analysis. The veterinary cut-off yielded an accuracy of 94% with a sensitivity and specificity of 94% (95% confidence intervals [CI] 0.81, 0.99) and 94% (95% CI 0.86, 0.98), respectively. Applying the human guidelines did not improve overall accuracy (89%), and yielded a sensitivity and specificity of 97% (95% CI 0.86, 1.00) and 86% (95% CI 0.77, 0.92), respectively. The veterinary cut-off value of ≥100,000 CFU/mL for voided urine is appropriate for determining significant bacteriuria in the majority of dogs with suspected UTI if specimens are refrigerated and cultured on the day of collection.

Bacterial urinary tract infections associated with transitional cell carcinoma in dogs

Background

Urinary tract infections (UTI) are believed to be common in dogs with transitional cell carcinoma (TCC), but incidence and contributing factors have not been reported.

Objectives

To determine the frequency and bacterial agents associated with UTI in dogs with TCC and define contributing factors.

Animals

Eighty‐five dogs with a history of urogenital TCC undergoing treatment with chemotherapy that had at least 1 urine culture performed.

Methods

Medical records and culture results were retrospectively reviewed and ultrasound images were reviewed when available. Clinical factors were evaluated statistically for association with positive culture.

Results

Fifty‐five percent (47/85) of dogs had at least 1 positive culture during the course of treatment. Female dogs (80%, 40/50) were more likely than male dogs (29%, 10/35) to have at least 1 positive culture. Ultrasound examination determined that female dogs were more likely to have urethral (74%, 31/42) or trigonal tumor involvement (71%, 30/42) compared to male dogs (32%, 9/28 and 43%, 12/28, respectively). The most commonly isolated organisms were Staphylococcus spp. (23.9%, 29/121) and Escherichia coli (19.8%, 24/121). Dogs with urethral involvement of TCC were significantly more likely to have at least 1 positive culture than dogs without urethral involvement (75%, 30/40 versus 30%, 9/30).

Conclusions

Urinary tract infection is common in dogs with TCC highlighting the importance of regular monitoring for bacterial cystitis in dogs with TCC. In addition, clinical factors such as tumor location and sex may be predictive of positive culture and can help clinicians assess the risk of UTI.

Urinary incontinence in the bitch: an update

Urinary incontinence (UI), defined as the involuntary loss of urine during the filling phase of the bladder (Abrams et al. 2002), is a commonly seen problem in veterinary practice. Urinary sphincter mechanism incompetence (USMI) after spaying is the most common micturition disorder, and its medical treatment is normally successful, even though the underlying pathophysiological mechanism is not fully understood. Hormonal changes inducing structural and functional alterations in the bladder, as well as in the urethra composition, are discussed. To manage incontinent patients successfully, possible underlying abnormalities besides USMI should be ruled out. In the majority of cases, history, physical examination and simple tests including urinalysis and urine bacterial culture lead to a presumed aetiology. If USMI is the most likely cause, then the advantage of further diagnostic tests should be discussed with the owner before starting a trial therapy with alpha-adrenergic drugs. Potential side effects of this therapy have to be mentioned even though they rarely occur. It is important to thoroughly evaluate the success of the initial treatment. Its failure should lead to further diagnostic testing. Specialized clinical assessments may provide an aetiological diagnosis, and this could serve as a basis for discussing further treatment options. Surgical procedures, which may in rare cases cause irreversible side effects, may be instituted. If incontinence reoccurs after initial treatment was successfully performed, the diagnostic work-up including urinalysis should always be repeated. As results of urinalysis did not correlate well with results of bacterial culture, a urine culture is recommended (Comer and Ling 1981). Cystocentesis is the preferred method of urine collection (Bartges 2004). Equivocal results of quantitative cultures of urine samples obtained during midstream voiding or by catheterization require repeat collection by cystocentesis (Comer and Ling 1981).

Feline urinary tract pathogens: prevalence of bacterial species and antimicrobial resistance over a 10-year period

The purpose of this retrospective study was to identify bacterial species in cats with bacterial urinary tract infections (UTIs) and to investigate their antimicrobial susceptibilities over a 10-year period. Three hundred and thirty cultures from 280 cats were included in the study. The mean age of affected cats was 9.9 years; female cats with bacterial UTIs were significantly older than male cats with UTIs. The most common pathogen identified was Escherichia coli (42.3 per cent), followed by Streptococcus species (19.3 per cent), Staphylococcus species (15.6 per cent), Enterococcus species (6.6 per cent) and Micrococcaceae (5.8 per cent). Forty specimens (12.1 per cent) yielded growth of more than one isolate. Streptococcus and Enterococcus isolates were resistant to a significantly higher number of antimicrobial agents than E coli and Staphylococcus species isolates. Applying the formula to select rational antimicrobial therapy, bacterial isolates were most likely to be susceptible to nitrofurantoin, amoxicillin clavulanic acid, enrofloxacin and gentamicin. The antimicrobial impact factor for nitrofurantoin increased significantly over the 10-year period, whereas there was no significant change in antimicrobial impact factors for doxycycline, trimethoprim-sulfamethoxazole, gentamicin, enrofloxacin, cephalothin and amoxicillin clavulanic acid. The detected changes in in vitro antimicrobial efficacy could help to develop hospital-specific guidelines for antimicrobial use to prevent the further development of resistance in feline uropathogens.

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

Background

Bacterial urinary tract infection (UTI) is a common reason for antimicrobial therapy in dogs.

A reported increase in multi-drug resistance in canine bacterial pathogens, including resistance to extended-spectrum cephalosporins (ESC) is of concern as antimicrobial resistance complicates therapy in dogs. In addition, it is a possible public health concern.

The objectives of this study were to investigate the relative prevalence of pathogens in urine samples from dogs with urinary tract infection sampled at referral hospitals, clinics and mixed veterinary practices and to investigate if this was influenced by sample material or by contamination of the culture. The second objective was to assess the susceptibility patterns to clinically relevant antimicrobials and to investigate if this was influenced by whether the samples originated from smaller clinics or from referral hospitals and to perform active screening for the presence of Enterobacteriaceae resistant to ESC.

Results

Escherichia coli was the most frequently isolated pathogen (68%) followed by staphylococci (11%).

E. coli isolates were found significantly more often in pure culture than in contaminated samples. Staphylococcus pseudintermedius and Staphylococcus aureus isolates were significantly more prevalent in pre-incubated samples compared to samples submitted as non-incubated media.

Susceptibility to the majority of the tested first-line antimicrobials was common. Multiresistance was rare, and these isolates were all susceptible to at least one relevant antimicrobial. Isolates in samples from small animal clinics or mixed veterinary practices were less likely to be susceptible compared to isolates originating from referral animal hospitals. ESC-resistant Enterobacteriacae isolates were found in one per cent of the positive cultures. Bacteria with transferable ESC resistance were confirmed in one dog. The gene demonstrated was bla_CMY2.

Conclusions

Choice of sample material might influence the possibility of detecting Staphylococcus pseudintermedius and Staphylococcus aureus isolates in clinical cases of UTI in dogs. Based on the study results, use of first-line antimicrobials is a rational empirical antimicrobial therapy for the studied dog population.

E. coli was the most prevalent pathogen, but prevalence of infection with ESC resistant Enterobacteriaceae including E. coli was low, as such isolates were found in only one per cent of the positive cultures.

Risk factors associated with struvite urolithiasis in dogs evaluated at general care veterinary hospitals in the United States

OBJECTIVE

To identify factors associated with development of struvite urolithiasis in dogs evaluated at general care veterinary hospitals in the United States.

DESIGN

Retrospective case-control study.

ANIMALS

508 dogs with a first-time diagnosis of struvite urolithiasis and 7,135 control dogs.

PROCEDURES

Electronic medical records of all dogs evaluated at 787 general care veterinary hospitals in the United States between October 2007 and December 2010 were reviewed to identify dogs that developed struvite urolithiasis and 2 groups of control dogs with no history of urolithiasis. Information extracted included diet, age, sex, neuter status, breed size category, hospital location, and date of diagnosis. Urinalysis results, urolith composition, and other disease conditions were recorded if applicable. Potential risk factors were assessed with univariable and multivariable regression analysis.

RESULTS

Toy- or small-sized breeds had significantly greater odds of struvite urolithiasis, compared with medium- or large-sized breeds. Neutering significantly increased the odds of this outcome in females only; sexually intact females were more likely to develop struvite urolithiasis than were sexually intact males, but only up to 5 years of age. Urinary factors significantly associated with the outcome were basic (vs acidic) pH, presence of RBCs or WBCs, protein concentration > 30 mg/dL, and ketone concentration ≥ 5 mg/dL.

CONCLUSIONS AND CLINICAL RELEVANCE

Evaluation of demographic characteristics and urinalysis results may be useful in the early identification of struvite urolithiasis in dogs. Periodic urinalysis in dogs is recommended because of the potential health impact of a late diagnosis of urolithiasis.

Diagnostic accuracy of a point-of-care urine bacteriologic culture test in dogs

OBJECTIVE

To determine diagnostic accuracy of a compartmented bacteriologic culture and antimicrobial susceptibility testing plate (CCSP) for detection of bacterial urinary tract infection (UTI) in dogs and antimicrobial susceptibility testing of bacterial isolates.

DESIGN

Evaluation study.

SAMPLE

62 frozen, previously characterized bacterial isolates from canine urine cultures and 147 canine urine samples.

PROCEDURES

The study was conducted in 2 phases: preliminary assay validation (phase 1) and diagnostic validation (phase 2). For phase 1, the frozen bacterial isolates were revitalized and tested with the CCSP and with standard aerobic microbiological culture (SAMC). For phase 2, the urine samples were tested with the CCSP and SAMC in parallel.

RESULTS

For phase 1, after 24 hours of culture, 46 of 62 (74%) bacterial isolates had growth on the CCSP and all (100%) had growth in SAMC. For bacterial isolates with growth, the CCSP allowed correct identification of 45 of 46 (98%) isolates. Isolates yielding no growth on the CCSP were gram-positive cocci (Staphylococcus spp [n = 7] and Enterococcus spp [9]). In phase 2, the overall diagnostic accuracy of the CCSP, compared with SAMC, was 94% (sensitivity, 81%; specificity, 99%). The positive predictive value was 98% and negative predictive value was 92%. Susceptibility results for enrofloxacin and trimethoprim-sulfamethoxazole as determined with the CCSP had greatest concordance with those determined by SAMC (71% and 96%, respectively), compared with other antimicrobial susceptibilities.

CONCLUSIONS AND CLINICAL RELEVANCE

Use of the CCSP led to accurate exclusion of UTI in dogs without a UTI but was less reliable for diagnosis of UTI, particularly infections caused by gram-positive cocci. Standard aerobic microbiological culture remains the gold standard for detection of UTI in dogs.

Vaginal microbiota of spayed dogs with or without recurrent urinary tract infections

Background

Limited information is available regarding the vaginal microbiota of normal spayed dogs and spayed dogs with recurrent UTIs. Vaginal lactic acid‐producing bacteria (LAB) have been associated with decreased frequency of recurrent urinary tract infection in women and may have a protective role within the urinary tract of female dogs.

Hypothesis/Objectives

Spayed dogs with historical recurrent UTI will have decreased prevalence of LAB and increased prevalence of uropathogenic bacterial populations in the vaginal microbiota when compared with the vaginal microbiota of healthy, spayed dogs.

Animals

Twenty‐one client‐owned adult spayed female dogs with historical recurrent UTI and 23 healthy, spayed female dogs without a history of recurrent UTI.

Methods

Dogs were placed into a recurrent UTI group or control group in this prospective study. Bacterial populations were isolated and characterized from vaginal swabs obtained from each dog.

Results

The most common bacterial isolates obtained from the vaginal tract of all dogs were Escherichia coli (11/44) and S. pseudintermedius (13/44). E. coli was isolated from the vaginal tract of 8 of 21 (38%) dogs in the rUTI group and 3 of 23 (13%) dogs in the control group (P = .08). LAB were isolated from 7 of the 44 dogs. Two of these 7 dogs were in the rUTI group and 5 of the 7 dogs were in the control group.

Conclusions and Clinical Importance

The vaginal microbiota of spayed female dogs with recurrent UTI was similar to the control population of normal, spayed female dogs.

Evaluation of urinalyses from untreated adult cats with lower urinary tract disease and healthy control cats: predictive abilities and clinical relevance

This case-controlled study evaluated urinalyses from 111 primary cases diagnosed with feline lower urinary tract disease (FLUTD) and 101 healthy control cats. Urine samples were analysed by standardised procedures, and differences between the two groups were compared by multivariable logistic regression analysis, while controlling for age, body weight, gender and reproductive status. Further, the ability of using urine sediment findings to predict bacteriuria was evaluated. In addition, urinalyses from cats with bacterial cystitis, idiopathic cystitis, urolithiasis and urethral plugs were compared. The main findings were that increasing body weight was significantly associated with increased odds of FLUTD, while the influence of age and reproductive status was of less importance. Increasing amounts of red blood cells and epithelial cells were significantly associated with increased odds of FLUTD. The predictive ability of using bacterial sediment findings to predict bacterial growth was dependent on subjective grading of the amount of bacteria in the sediment and was, at best, only moderate. The few significant differences found between the different FLUTD diagnoses were of limited diagnostic value.

Evaluation of a catalase-based urine test for the detection of urinary tract infection in dogs and cats

BACKGROUND

Bacterial infection of the urinary tract is a common disorder in dogs and cats. Although microscopic examination of urine sediment is routinely used to screen for infection, this test can lack sensitivity or require expertise. A reliable in-clinic screening test would be a useful adjunct for the identification of dogs and cats with bacterial urinary tract infection (UTI).

HYPOTHESIS

That a catalase-based urine test (Accutest Uriscreen™) is a more sensitive screening test for UTI in dogs and cats than urine microscopic sediment examination.

ANIMALS

One hundred and sixty client-owned dogs and cats.

METHODS

Surplus urine from animals presented to a veterinary teaching hospital was used in this prospective observational study. A routine urinalysis, aerobic bacterial culture, and the Uriscreen test were performed on cystocentesis samples. Sensitivity and specificity with 95% confidence intervals and positive and negative likelihood ratios were calculated for Uriscreen and microscopic sediment examination using culture results as the gold standard.

RESULTS

Bacterial culture was positive in 27/165 (16.4%) samples. The sensitivity, specificity, and positive and negative likelihood ratios for the Uriscreen were 89%, 71%, 3.0, and 0.15, respectively. Sensitivity, specificity, and positive and negative likelihood ratios for urine sediment microscopic examination were 78%, 90%, 7.8, and 0.24, respectively.

CONCLUSIONS AND CLINICAL IMPORTANCE

The Uriscreen is a more sensitive screening test for UTI in dogs and cats than sediment examination; however, the urine sediment examination was more specific. A negative Uriscreen result helps exclude UTI; however, urine bacterial culture is still necessary to exclude or confirm UTI in all cases.

Elevation of neutrophil gelatinase-associated lipocalin (NGAL) in non-azotemic dogs with urinary tract infection

Neutrophil gelatinase-associated lipocalin (NGAL) is a promising biomarker in humans and dogs with kidney disease. This protein is expressed by many cells including renal tubular cells and neutrophils. The aim of this study was to evaluate the effect of urinary tract infection (UTI) on urinary NGAL (uNGAL) concentration in dogs. Urine culture and measurement of uNGAL level were performed in 80 non-azotemic dogs suspected of UTI and 19 healthy dogs. Dogs were divided in three groups: 19 healthy dogs, 25 dogs with positive culture and 55 dogs suspected of UTI but with negative culture. uNGAL and uNGAL/Creatinine was significantly higher (P < 0.0001) in dogs with UTI (14.22 ng/mL;19.74 μg/g) compared to Healthy (0.24 ng/mL;0.11 μg/g) and Negative (1.13 ng/mL;1.28 μg/g) dogs. A uNGAL value <3.38 ng/mL had a negative predictive value for UTI of 87%. Presence of UTI has to be considered when uNGAL is used to detect kidney disease.

The effect of an oral probiotic containing lactobacillus, bifidobacterium, and bacillus species on the vaginal microbiota of spayed female dogs

BACKGROUND

Recurrent urinary tract infections (UTIs) are often difficult to treat. Vaginal colonization with lactic acid-producing bacteria (LAB) is associated with reduced frequency of recurrent UTIs in women. Oral probiotics might help increase the prevalence of vaginal LAB and decrease the frequency of recurrent UTIs in dogs.

HYPOTHESIS

Administration of an oral probiotic supplement containing Lactobacillus, Bifidobacterium, and Bacillus species will increase the prevalence of LAB in the vagina of dogs.

ANIMALS

Thirty-five healthy, spayed female dogs without history of recurrent UTIs.

METHODS

Prospective, controlled study. Enrolled dogs received an oral probiotic supplement for 14 or 28 days. A vaginal tract culture was obtained from each dog before and after oral probiotic administration. Twenty-three dogs received the oral probiotic supplement daily for a period of 14 days and 12 dogs received the oral probiotic supplement daily for a period of 28 days.

RESULTS

Lactic acid-producing bacteria were isolated from 7 of 35 dogs prior to probiotic administration. After the treatment course, 6 of 35 dogs had LAB isolated. Only one of these dogs had LAB (Enterococcus canintestini) isolated for the first time. Enterococcus canintestini was the most common LAB isolated from all dogs in this study, although it was not included in the probiotic supplement.

CONCLUSIONS AND CLINICAL IMPORTANCE

Lactic acid-producing bacteria are not a common isolate from the vaginal vault of dogs. Administration of this oral probiotic supplement for a 2- or 4-week period did not increase the prevalence of vaginal LAB in dogs.

Usability application of multiplex polymerase chain reaction in the diagnosis of microorganisms isolated from urine of patients treated in cancer hospital

Background

The objective of this study was: i) to compare the results of urine culture with polymerase chain reaction (PCR) -based detection of microorganisms using two commercially available kits, ii) to assess antimicrobial susceptibility of urine isolates from cancer patients to chosen antimicrobial drugs and, if necessary, to update the recommendation of empirical therapy.

Materials and methods.

A one-year hospital-based prospective study has been conducted in Greater Poland Cancer Centre and Genetic Medicine Laboratory CBDNA Research Centre in 2011. Urine cultures and urine PCR assay from 72 patients were examined

Results

Urine cultures and urine PCR assay from 72 patients were examined. Urine samples were positive for 128 strains from which 95 (74%) were identical in both tests. The most frequently isolated bacteria in both culture and PCR assay were coliform organisms and Enterococcus spp. The Gram negative bacilli were most resistant to cotrimoxazol. 77.2% of these bacilli and 100% of E. faecalis and S. agalactiae were sensitive to amoxicillin-clavulanic acid. 4.7% of Gram positive cocci were resistant to nitrofurantoin.

Conclusions

The PCR method quickly finds the causative agent of urinary tract infection (UTI) and, therefore, it can help with making the choice of the proper antimicrobial therapy at an early stage. It appears to be a viable alternative to the recommendations made in general treatment guidelines, in cases where diversified sensitivity patterns of microorganisms have been found.

Comparison of routine urinalysis and urine Gram stain for detection of bacteriuria in dogs

OBJECTIVE

To determine the utility of performing urine Gram stain for detection of bacteriuria compared to routine urine sediment examination and bacterial aerobic urine culture.

DESIGN

Prospective, observational study.

SETTING

University teaching hospital.

ANIMALS

Urine samples acquired via cystocentesis through convenience sampling from 103 dogs presenting to a tertiary referral institution.

INTERVENTIONS

All samples underwent routine urinalysis, including sediment examination, as well as urine Gram stain and quantitative bacterial aerobic urine culture.

MEASUREMENTS AND MAIN RESULTS

The urine Gram stain demonstrated improved sensitivity (96% versus 76%), specificity (100% versus 77%), positive predictive value (100% versus 83%), and negative predictive value (93% versus 69%) when identifying bacteriuria, compared to routine urine sediment examination.

CONCLUSIONS

The urine Gram stain is highly sensitive and specific when detecting the presence of bacteria in canine urine samples. Gram staining should be considered when bacteriuria is highly suspected and requires rapid identification while bacterial culture is pending.