Xanthinuria in a familial group of Munchkin cats and an unrelated domestic shorthair cat.

CASE SERIES SUMMARY: Four confirmed cases of xanthinuria in cats, and one suspected case based on pedigree analysis, were identified. Clinical presentations varied and included haematuria, pollakiuria, dysuria, and urethral and ureteral obstruction. All cats had upper urinary tract uroliths. Diagnosis was obtained through infrared mass spectrometry of uroliths or urine. Clinical signs commenced at 3-8 months of age and reduced in all cats in the medium to long term after the introduction of a protein-restricted diet. Four cats were castrated males and one was a spayed female. Cases consisted of four Munchkin pedigree cats and one unrelated domestic shorthair cat. All four affected Munchkin pedigree cats were related, with three cases full siblings and the fourth case a half-sibling. No connection to the Munchkin pedigree could be established for the domestic shorthair cat. A candidate causative genetic variant (XDH p.A681V) proposed for this cat was excluded in the Munchkin family. RELEVANCE AND NOVEL INFORMATION: All affected cats presented diagnostic challenges and routine urinalysis was insufficient to obtain a diagnosis. Cases of feline xanthinuria may be underdiagnosed due to situations where uroliths cannot be retrieved for analysis and there is an inability to make a diagnosis using crystal morphology alone on routine urinalysis. Metabolic screening of urine may provide an effective mechanism to confirm xanthinuria in suspected cases where uroliths are inaccessible or absent. In this case series, male cats were more common. Their anatomy may increase the risk of lower urinary tract signs and urethral obstruction developing secondary to xanthine urolithiasis. A protein-restricted diet appears to reduce clinical signs as part of long-term management. PLAIN LANGUAGE SUMMARY: Four closely related Munchkin cats and one domestic shorthair cat were found with a suspected genetic disease causing high levels of xanthine in their urine. The case series looks at similarities and differences in their clinical signs, as well as difficulties experienced in obtaining a correct diagnosis. All cats had upper urinary tract stones and required metabolic testing of the stones or urine to diagnose. All cats were young when their clinical signs started and were on a high-protein diet. Four cats were desexed males and one was a desexed female. A genetic variant that may have caused the disease in the domestic shorthair cat was ruled out in the Munchkin family. Cases of high xanthine levels in feline urine may be underdiagnosed as the stones may not be accessed for testing. In this case series, male cats were more common. Their anatomy may increase the risk of lower urinary tract signs. A protein-restricted diet appears to reduce clinical signs as part of long-term management.

Blood plasma and urinary biomarkers of oxidative stress in cats with urethral obstruction.

BACKGROUND: This study aimed to investigate variations of the oxidative status in cats affected by urethral obstruction (UO) under Feline Idiopathic Cystitis (FIC) and Bacterial Cystitis (BC), in comparison with a group of healthy subjects. In both groups, the levels of several markers (either direct or indirect) indicative of the oxidative attack and of the antioxidant response were analyzed on plasma and urine samples. In particular, the plasma samples were evaluated for nitric oxide (NO), hydroperoxides derived by reactive oxygen activity (d-ROMs test), superoxide anion (O2-), glutathione peroxidase activity (GPx), superoxide dismutase activity (SOD), and ferric reducing antioxidant power (FRAP test); while on urine the levels of NO, d-ROMs, FRAP, SOD, malondialdehyde (MDA) and 8-hydroxydeoxyguanosine (8-OHdG) were measured. Urine of UO patients was also subjected to urine-culture test. RESULTS: The analytical data on plasma showed that UO, independently of the FIC or BC etiology, induced the insurgence of oxidative stress conditions at the systemic level. In the urine of the UO patients, except for SOD that increased, the markers of redox status were markedly decreased due probably their compromised filtration, thus suggesting involvement of renal function (assessed also by the high levels of plasma creatinine and proteinuria) with no oxidative damage of the lower urinary tract. Moreover, the adoption of a novel oxidative stress index' (OSI) allowed to establish, by means of a numerical value, the different degrees of oxidative stress conditions for single UO patients, both in terms of oxidative attack and antioxidant response. CONCLUSIONS: Feline urethral obstruction, induced by Idiopathic Cystitis and Bacterial Cystitis, causes oxidative stress conditions at the systemic level that do not interest the lower urinary tract. Despite to the high variability of the profiles of oxidative stress indexes both in healthy and UO patients, the determination of OSI made possible the evaluation of their single degrees of oxidative stress. Possibly the results of this investigation can be compared with those of correspondent pathologies both in humans and in other animal species.

Evaluation of a urine dipstick protein to urine specific gravity ratio for the detection of proteinuria in dogs and cats.

BACKGROUND: The utility of urine dipsticks for the quantification of proteinuria is limited because of the influence of urine specific gravity (USG). To circumvent the need for urine protein creatinine ratios (UPCR) some have proposed a calculated dipstick urine protein to USG ratio (DUR) for the detection of proteinuria. However, the performance of DUR has not been evaluated in veterinary patients. OBJECTIVES: Evaluate the correlation between DUR and UPCR, while also assessing the effect of urine characteristics on this relationship and evaluating the performance of DUR in detecting proteinuria. ANIMALS: Urine samples from 308 dogs and 70 cats. METHODS: Retrospective cohort study of urinalyses and UPCRs from dogs and cats collected between 2016 and 2021. RESULTS: Both canine and feline urine samples showed a positive moderate correlation between the UPCR and DUR. The correlation was not influenced by the presence of active urine sediment, glucosuria, or urine pH. In detecting canine urine samples with a UPCR >0.5, an optimal DUR of 1.4 had sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 89%, 83%, 96%, and 63%, respectively. In detecting feline urine samples with a UPCR >0.4, an optimal DUR of 2.1 had sensitivity, specificity, PPV, and NPV of 70%, 100%, 100%, and 75%, respectively. CONCLUSIONS AND CLINICAL IMPORTANCE: Use of the DUR can be a relatively reliable method for identification of proteinuria. However, given its poor NPV, the DUR cannot be recommended for exclusion of proteinuric patients.

Assessment of inter-observer agreement among experienced and inexperienced observers and an automated device for dipstick urinalysis in dogs and cats.

Standard visual urine dipstick analysis (UDA) is performed routinely in veterinary medicine; results can be influenced by both the operator and the method. We evaluated the agreement of results for canine and feline urine samples analyzed using a 10-patch dipstick (Multistix10SG; Siemens), both visually under double-anonymized conditions by students and a laboratory technician, and with an automated device (AD; Clinitek Status, Siemens). The mean concordance for semiquantitative urinalysis results between students and the technician and between students and the AD was fair (κ0.21-0.40) in dogs and cats; concordance was moderate between the technician and the AD (κ0.41-0.60) in dogs and good (κ0.61-0.80) in cats. For pH, the mean concordance between students and the technician and between the technician and the AD was good (ρ0.80-0.92) in dogs and cats; concordance was good between students and the AD (ρ0.80-0.92) in dogs and moderate (ρ0.59-0.79) in cats. Repeatability was higher (p < 0.001) for the technician and the AD than for a student. We found good agreement between UDA performed by an experienced operator and an AD in dogs and cats but found low reproducibility and low repeatability for urinalysis performed by an inexperienced operator.

Evaluation of an enzyme immunoassay and immunodiffusion for detection of anti-Histoplasma antibodies in serum from cats and dogs.

BACKGROUND: Histoplasma antigen and anti-Histoplasma antibody detection are used to support the diagnosis of histoplasmosis. There is a paucity of published data on antibody assays. OBJECTIVES: Our primary hypothesis was that anti-Histoplasma immunoglobulin G (IgG) antibody detection using enzyme immunoassay (EIA) will be more sensitive as compared to immunodiffusion (ID). ANIMALS: Thirty-seven cats and 22 dogs with proven or probable histoplasmosis; 157 negative control animals. METHODS: Residual stored sera were tested for anti-Histoplasma antibodies using EIA and ID. Results of urine antigen EIA were reviewed retrospectively. Diagnostic sensitivity was calculated for all three assays and compared between immunoglobulin G (IgG) EIA and ID. The diagnostic sensitivity of urine antigen EIA and IgG EIA, interpreted in parallel, was reported. RESULTS: Sensitivity of IgG EIA was 30/37 (81.1%; 95% confidence interval [CI], 68.5%-93.4%) in cats and 17/22 (77.3%; 95% CI, 59.8%-94.8%) in dogs. Diagnostic sensitivity of ID was 0/37 (0%; 95% CI, 0%-9.5%) in cats and 3/22 (13.6%; 95% CI, 0%-28.0%) in dogs. Immunoglobulin G EIA was positive in all animals (2 cats and 2 dogs) with histoplasmosis but without detectable antigen in urine. Diagnostic specificity of IgG EIA was 18/19 (94.7%; 95% CI, 74.0%-99.9%) in cats and 128/138 (92.8%; 95% CI, 87.1%-96.5%) in dogs. CONCLUSION AND CLINICAL IMPORTANCE: Antibody detection by EIA can be used to support the diagnosis of histoplasmosis in cats and dogs. Immunodiffusion has an unacceptably low diagnostic sensitivity and is not recommended.

Urinary liver-type fatty acid-binding protein in clinically healthy elderly cats: Evaluation of its potential to detect IRIS stage 1 chronic kidney disease and borderline proteinuria.

BACKGROUND: Urinary liver-type fatty acid-binding protein (uL-FABP) is a promising biomarker to detect early chronic kidney disease (CKD) in cats. Few healthy cats show increased uL-FABP for unknown reasons. OBJECTIVES: The objective of this study was to evaluate uL-FABP in a large healthy elderly cat population comparing cats with and without International Renal Interest Society (IRIS) stage 1 CKD and with and without borderline proteinuria. METHODS: This was a cross-sectional study. One hundred ninety-six clinically healthy client-owned cats of ≥7 years old were subdivided based on two criteria: (1) having either IRIS stage 1 CKD or no evidence of CKD and (2) having borderline proteinuria or no proteinuria. Urinary L-FABP was measured using a validated commercially available feline L-FABP ELISA. RESULTS: Overall, uL-FABP was detectable in 6/196 (3%) healthy elderly cats. For the first subdivision, nine (5%) cats had IRIS stage 1 CKD, 184 cats had no evidence CKD and three cats were excluded. All cats with IRIS stage 1 CKD had uL-FABP concentrations below the detection limit, whereas 6/184 (3%) cats without IRIS stage 1 CKD had detectable uL-FABP concentrations (median 1.79 ng/ml, range 0.79-3.66 ng/ml). For the second subdivision, 47 (24%) cats had borderline proteinuria, 147 cats had no proteinuria and two cats were excluded. One of the borderline proteinuric cats had a detectable uL-FABP concentration, whereas the other five cats with detectable uL-FABP concentrations were non-proteinuric. CONCLUSION: With the current assay, the screening potential of uL-FABP as an early biomarker for feline CKD is limited as uL-FABP was rarely detected in clinically healthy elderly cats independently of the presence of either IRIS stage 1 CKD or borderline proteinuria.

The effect of non-absorbent hydrophobic sand litter on the urine protein-to-creatinine ratio in feline urine.

BACKGROUND: Proteinuria can be quantified through the measurement of the urine protein-to-creatinine ratio (UPC). Voided urine samples in cats are often exposed to a non-absorbable litter substrate prior to collection and urinalysis. Little is known about the effect exposure to such substrates has on pre-analytical variability of UPC measurements. OBJECTIVES: The aim of this study was to assess agreement between UPC measurements from urine obtained by cystocentesis before and after exposure to non-absorbent hydrophobic sand for 24 hours. METHODS: UPCs were measured in 40 urine samples obtained by cystocentesis from 39 cats (baselineUPC). Urine was then exposed to non-absorbent hydrophobic sand litter for 24 hours, recovered, and repeat UPCs were measured (litterUPC). Agreement between paired measurements and the presence of any bias or error was evaluated using Bland-Altman analysis Passing-Bablok regression analysis, respectively. Cohen's kappa was used to measure agreement for the International Renal Interest Society (IRIS) proteinuria classification of samples. Observed total error (TEobs ) was calculated for the laboratory analyzer and compared against absolute percentage changes in paired UPC measurements. RESULTS: Neither proportional nor constant error was identified using Passing-Bablok regression between baselineUPC and litterUPC. Visual inspection of the Bland-Altman plot revealed good agreement, with 95% of paired measures falling within the limits of agreement (LOA). Cohen's kappa demonstrated almost perfect agreement for the IRIS classification of proteinuria between baselineUPC and litterUPC. Absolute percentage changes of paired UPC measurements outside of the LOAs were lower than the inter-assay TEobs . CONCLUSIONS: Feline urine exposed to non-absorbent hydrophobic sand litter appears acceptable for UPC measurements.

Risk factors and clinical relevance of positive urine cultures in cats with subcutaneous ureteral bypass.

BACKGROUND: The objective of the study was to report the incidence and risk factors associated with positive urine bacterial cultures as well as long-term outcome in cats with subcutaneous ureteral bypass (SUB) devices. RESULTS: Medical records of cats that underwent SUB device placement were retrospectively reviewed. Signalment of the cat, laterality of the ureteral obstruction, surgery, anesthesia and hospitalization duration, bacterial culture results and follow-up data were retrieved. Thirty-two cats met the inclusion criteria. Four cats (12.5%) had a positive intraoperative culture, with two of them being treated successfully. Ten cats out of 28 (35.7%) were documented with a positive urine culture during follow-up period, with a median time between discharge and identification of the first positive urine culture of 159 days (range 8-703 days). Bacteriuria resolved in 60% of cats (6/10). Escherichia coli was the most common organism, isolated in 4 out of 10 postoperative urine cultures. Overall, subclinical bacteriura was documented for 6 of 32 (18.8%) cats and 5 of 32 (15.6%) cats displayed clinicals signs suggestive of persistent UTI. One cat had subclinical bacteriuria. Three cats died during the follow-up period. There was a significant difference between negative and positive urine bacterial culture groups in median hospitalization duration (5 days versus 6 days, P = 0.022) and in median body condition score (5/9 versus 4/9, P = 0.03). Cats with a longer hospital stay and with a lower body condition score were more likely to have a positive urine culture during follow-up period. CONCLUSIONS: SUB device placement surgery is associated with complications such as chronic bacteriuria. Bacteriuria in our study resolved with appropriate antibiotic treatment in more than half of cats. Risk factors identified for positive urine culture were a longer hospitalization duration and a decreased body condition score.

Preliminary study of urinary excretion of liver-type fatty acid-binding protein in a cat model of chronic kidney disease.

Urinary liver-type fatty acid-binding protein (uL-FABP) is a clinically useful biomarker for monitoring chronic kidney disease (CKD) in humans. However, long-term monitoring of uL-FABP in CKD cats has not been reported. The objective of this preliminary study was to investigate whether the urinary excretion of L-FABP could predict the deterioration of renal function in 2 CKD model cats. Urinary liver-type fatty acid-binding protein (uL-FABP) increased before standard renal biomarkers, including serum creatinine, blood urea nitrogen, and symmetric dimethylarginine, in 1 cat with deteriorating renal function, but remained low and relatively stable in another cat with stable renal function. Our results suggest that uL-FABP is a potential clinical biomarker for predicting the progression of CKD in cats, as it is in humans.

La protéine urinaire de liaison aux acides gras de type hépatique (uL-FABP) est un biomarqueur cliniquement utile pour la surveillance de l'insuffisance rénale chronique (MRC) chez l'homme. Cependant, aucune surveillance à long terme de l'uL-FABP chez les chats atteints d'IRC n'a été signalée. L'objectif de cette étude préliminaire était de déterminer si l'excrétion urinaire de L-FABP pouvait prédire la détérioration de la fonction rénale chez deux chats modèles de CKD. La protéine uL-FABP a augmenté avant les biomarqueurs rénaux standards, y compris la créatinine sérique, l'azote uréique sanguin et la diméthylarginine symétrique, chez un chat dont la fonction rénale se détériorait, mais est restée faible et relativement stable chez un autre chat dont la fonction rénale était stable. Nos résultats suggèrent que l'uL-FABP est un biomarqueur clinique potentiel pour prédire la progression de l'IRC chez le chat, comme c'est le cas chez l'homme.(Traduit par Docteur Serge Messier).

Molecular characterization of Feline paramyxovirus and Feline morbillivirus in cats from Brazil.

This study is aimed at detecting Feline paramyxovirus (FPaV) and Feline morbillivirus (FeMV) in 35 urine samples from domestic cats, collected in 2019, with or without clinical signs of uropathies using a reverse transcription-polymerase chain reaction (RT-PCR) followed by semi-nested polymerase chain reaction (SN-PCR) assays to amplify a partial paramyxovirus L gene. Eight (22.9%) out of the 35 urine samples were positive for paramyxoviruses. Sequencing and phylogenetic analyses revealed that three samples were positive for FPaV, four samples were positive for FeMV, and it was not possible to determine which virus was present in one RT-SN-PCR positive urine sample. FPaV strains showed 100% nucleotide (nt) identity with each other and 97% nt identity with a Japanese 163 FPaV strain. The FeMV strains showed 85.9% nt identity with each other; three strains were similar to previously described Brazilian FeMV strains, and one strain clustered in a different branch of the phylogenetic tree together with the first described Chinese FeMV strain. This study provides the first description of FPaV strains in cats from Brazil and provides new information about the molecular characteristics of FPaV and FeMV strains circulating in domestic cats in Brazil.

Urine glucose concentration: A useful parameter as a surrogate for glycaemia on the first day of life in canine neonates.

INTRODUCTION: Hypoglycaemia is a well-known risk factor in neonatal puppies and kittens; glycaemia control is crucial during the first days of life. Kidneys immaturity provokes the presence of physiological glycosuria during the first 2-3 weeks of life in small animals. OBJECTIVES: The aim of this study was to evaluate the potential of glycosuria as a predictor of glycaemia in neonatal puppies during the first two weeks of life. METHODS: Prospective study. Thirty-three client-owned healthy neonatal puppies admitted to the Veterinary Teaching Hospital, Autonomous University of Barcelona, were included in the study and divided into four different groups according to the day of sampling (1, 4, 7, and 11 days post-delivery). Glucose levels in blood and urine samples were evaluated and compared between groups. Correlation between glucose levels in blood and urine was also determined. RESULTS: Hypoglycaemia was diagnosed in 17.14% of the puppies and only on day 1 after delivery. A positive and significant correlation between blood and urine glucose concentration on day 1 after delivery was observed. No significant correlation between blood and urine glucose was observed on days 4, 7 and 11 after delivery. CONCLUSIONS: Urine concentration of glucose is a useful parameter to establish glycaemic status on the first day of life in canine puppies.

Molecular epidemiology and genome analysis of feline morbillivirus in household and shelter cats in Thailand.

BACKGROUND: Feline morbillivirus (FeMV) has been discovered in domestic cats associated with tubulointerstitial nephritis, but FeMV is also detected in healthy cats. This research aimed to identify and characterize the FeMV strains detected in a Thai cat population. RESULTS: Two-hundred and ninety-two samples (131 urine and 161 blood) derived from 261 cats (61 sheltered and 200 household cats) were included for investigating the FeMV prevalence using real-time reverse transcription PCR. The overall prevalence of FeMV detection was 11.9% (31/261) among both samples, which accounted for 14.5% (19/131) and 7.5% (12/161) of the urine and blood samples, respectively. Among the FeMV-PCR positive cats, the FeMV-detected prevalence was insignificantly associated with healthy cats (58.1%; 18/31) or urologic cats (41.9%; 13/31). Full-length genome analysis of these FeMV-Thai strains revealed that their genomes clustered together in the FeMV-1A clade with up to 98.5% nucleotide identity. Selective pressure analysis showed that overall FeMV-1 has undergone negative selection, while positive selection sites were more frequently observed in the phosphoprotein gene. CONCLUSIONS: The detected FeMV infections in the Thai cat population were not correlated with urologic disorders, although the virus was more detectable in urine samples. The genetic patterns among the FeMV-1 Thai strains were more consistent. A large-scale study of FeMV in Thai cat samples is needed for further elucidation.

Kidney function and glucose metabolism in overweight and obese cats.

Background: In people, obesity and prediabetes mellitus might predispose to chronic kidney disease (CKD).Aims: To assess the association of overweight [Body condition score (BCS) >5] and glucose metabolism alterations, with established or potential markers of CKD. In addition, fructosamine and fasted blood glucose were compared as predictors of early abnormal glucose metabolism.Methods: 54 clinically healthy cats were included in a cross-sectional study comprising 25 neutered males and 29 (28 neutered) females aged 7.2 (5.5-9.4) years. Two potential markers of CKD, namely urinary free active transforming growth factor-ß1-creatinine ratio and urinary retinol binding protein-creatinine ratio were measured along with other parameters to assess CKD. A receiver operating curve was used to identify the best sensitivity and specificity of fructosamine to identify cats with fasting glucose >6.5 mmol/L.Results: No association was found between BCS and markers of CKD. Fructosamine was greater in cats with fasting glucose >6.5 mmol/L compared to those with fasting glucose ≤6.5 mmol/L. A fructosamine concentration ≥250 µmol/L was able to detect cats with hyperglycemia with a sensitivity of 77% and a specificity of 65%. Furthermore, fructosamine was more strongly correlated with fasting glucose than albumin-corrected fructosamine (r = 0.43, p = 0.002 vs r = 0.32, p = 0.026). Cats with higher fructosamine had lower serum symmetric dimethylarginine concentrations.Conclusion: The present study does not suggest an effect of obesity on renal function in domestic cats.Clinical relevance: Fructosamine might be of value for the diagnosis of prediabetes mellitus in cats.

Hyperthyroidism is not a risk factor for subclinical bacteriuria in cats: A prospective cohort study.

BACKGROUND: Subclinical bacteriuria is defined as a positive bacterial urine culture in the absence of clinical evidence of urinary tract infection (UTI). Studies have reported that hyperthyroid cats have UTIs (mostly subclinical) with prevalence rates of 12%-22%. Consequently, clinicians consider hyperthyroidism a risk factor for development of subclinical bacteriuria, and many recommend urine culture when evaluating hyperthyroid cats. OBJECTIVES: To compare the prevalence of subclinical bacteriuria (based on positive urine culture) in untreated hyperthyroid cats to that in euthyroid cats of similar age and sex. ANIMALS: Three hundred and ninety-three hyperthyroid cats presented for radioiodine treatment and 131 euthyroid cats (≥7 years of age) presented for routine examination. Cats with signs of lower urinary tract disease were excluded. METHODS: Prospective cohort study. Both hyperthyroid and euthyroid cats had urine collected by cystocentesis for complete urinalysis and culture. Data pertaining to age, sex, body condition, and serum thyroxine and creatinine concentrations also were acquired. Logistic regression was performed to evaluate for potential risk factors for subclinical bacteriuria. RESULTS: Hyperthyroid cats showed a low prevalence of subclinical bacteriuria (4.3%), which did not differ from that found in euthyroid cats (4.6%). Of the signalment factors evaluated, only female sex was a significant risk factor (odds ratio [OR], 6.9; P = .002). Furthermore, positive urine cultures were more likely in specimens with dilute urine concentration (<1.035), pyuria, or microscopic bacteriuria. CONCLUSIONS AND CLINICAL IMPORTANCE: Hyperthyroid cats are not at risk for subclinical bacteriuria. In the absence of lower urinary tract signs, no clinical benefit exists in routinely performing urine cultures when evaluating hyperthyroid cats.

Urine hemojuvelin in cats with naturally occurring kidney disease.

BACKGROUND: Soluble-type hemojuvelin in serum and urine has been shown to be a biomarker in humans for chronic kidney disease (CKD) and acute kidney injury (AKI). No similar research has been conducted on cats. OBJECTIVE: Urine hemojuvelin (u-hemojuvelin) can be used as a clinical indicator for cats with various renal diseases. ANIMALS: Eighteen healthy cats, 10 cats with AKI, 21 cats with acute-on-chronic kidney injury (ACKI), and 45 cats with CKD were enrolled. METHODS: The expression profile of u-hemojuvelin was assessed by Western blot analysis, whereas the u-hemojuvelin concentration was measured using an in-house sandwich ELISA. Each cat's u-hemojuvelin-to-creatinine ratio (UHCR) also was determined. RESULTS: Significant differences were found in both u-hemojuvelin concentration and UHCR between the control cats and the other cats (AKI, CKD, ACKI). Both u-hemojuvelin and UHCR had high areas under the receiver operator curve (AUROC) for diagnoses of AKI (u-hemojuvelin, 0.885; UHCR, 0.982), CKD (hemojuvelin, 0.869; UHCR, 0.959), and ACKI (hemojuvelin, 0.910; UHCR, 1). Late stage (International Renal Interest Society, IRIS stages 3 and 4) CKD cats had significantly higher u-hemojuvelin concentration and UHCR than did early stage cats (IRIS stages 1 and 2). Both u-hemojuvelin and UHCR were significantly correlated with high blood urea nitrogen, plasma creatinine, and plasma phosphate concentrations and with low hematocrit (Hct), red blood cell (RBC) count, and plasma albumin concentration. The UHCR values were also significantly correlated with white blood cell count in blood. CONCLUSION: Both u-hemojuvelin and UHCR potentially can serve as diagnostic indicators for a range of renal diseases in cats.

First report of pathogenic Leptospira spp. isolated from urine and kidneys of naturally infected cats.

Leptospirosis is one of the most widespread zoonotic diseases and can infect both humans and animals worldwide. Healthy cat, as a potential source of exposure to humans, are likely underestimated owing to the lack of overt clinical signs associated with Leptospira spp. infection in this species. The aim of the study was to determine the exposure, shedding, and carrier status of leptospires in shelter cats in Malaysia by using serological, molecular, and bacteriological methods. For this study, 82 healthy cats from two shelters were sampled. The blood, urine, and kidneys were tested using the microscopic agglutination test (MAT), polymerase chain reaction (PCR), and bacterial culture. On the basis of serological, molecular, and/or culture techniques, the total detection of leptospiral infection was 29.3% (n = 24/82). Through culture techniques, 16.7% (n = 4/24) of the cats that tested positive were carriers with positive kidney cultures, and one cat was culture positive for both urine and kidney. The Leptospira spp. isolates were identified as pathogenic L. interrogans serovar Bataviae through serological and molecular methods. Through serological techniques, 87.5% (n = 21/24) had positive antibody titers (100-1600) and most of the Bataviae serogroup (n = 19/21). Using PCR, 16.7% (n = 4/24) of cats were shown to have pathogenic Leptospira spp. DNA in their urine. Furthermore, three out of four culture positive cats were serology negative. The present study reports the first retrieval of pathogenic leptospires from urine and kidneys obtained from naturally infected cats. The results provide evidence of the potential role of naturally infected cats in the transmission of leptospires. Additionally, leptospiral infection occurs sub-clinically in cats. The culture isolation provides evidence that healthy cats could be reservoirs of leptospiral infection, and this information may promote the development of disease prevention strategies for the cat population.

Renal expression and urinary excretion of liver-type fatty acid-binding protein in cats with renal disease.

BACKGROUND: Liver-type fatty acid-binding protein (L-FABP) is a biomarker for early detection of renal disease in humans. Liver-type fatty acid-binding protein is cytotoxic oxidation products secreted from proximal tubules under ischemia and oxidative stress. OBJECTIVE: To examine renal expression and quantify urinary excretion of L-FABP in catswith renal disease. ANIMALS: One hundred and thirty-four client-owned cats including 34 cats with serum creatinine (sCre) values >1.6 mg/dL and 10 other cats that died in clinics. METHODS: Tissue expressions of L-FABP were examined by reverse transcription polymerase chain reaction and Western blotting. Urinary L-FABP (uL-FABP) and serum L-FABP (sL-FABP) levels were determined by enzyme-linked immunosorbent assay. Anti-liver-type fatty acid-binding protein antibody immunostained renal sections. RESULTS: Feline kidneys express L-FABP. Strong L-FABP signals were observed in the lumens of proximal tubular cells in 5 cats with high uL-FABP excretion, but not in 5 cats with low uL-FABP excretion. In 9 normal cats, uL-FABP index was <1.2 µg/g urinary creatinine (uCre). High uL-FABP indexes (>10.0 µg/g uCre) were detected in 7 of 100 cats with low sCre (<1.6 mg/dL) and 18 of 44 cats with high sCre (>1.6 mg/dL). There was a weak correlation between L-FABP index and sCre, serum symmetric dimethylarginine (SDMA), or blood urea nitrogen (BUN), and these correlation coefficients were increased by analyzing only data of cats with sCre >1.6 mg/dL. There was a weak correlation between u L-FABP index and sL-FABP in all tested cats, but not in cats with high sCre. CONCLUSIONS AND CLINICAL IMPORTANCE: This study demonstrates correlations between L-FABP and current renal biomarkers for chronic kidney disease in cats, such as sCre and SDMA. Liver-type fatty acid-binding protein may be a potential biomarker to predict early pathophysiological events in feline kidneys.

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.

Optimizing the u411 automated urinalysis instrument for veterinary use.

BACKGROUND: The Cobas u411 Analyzer (Roche Diagnostics) is an automated, reflectance photometry-based urinalysis instrument designed for use with Roche's CHEMSTRIP 10UA technology and human urine samples. OBJECTIVE: We aimed to optimize and validate the Cobas u411 Analyzer for use in canine and feline urinalysis. METHODS: Patient urine samples presenting to the Clinical Pathology Laboratory at the Colorado State University Veterinary Teaching Hospital were analyzed with the Cobas u411 and by manual readings in parallel. Initially, 223 canine and 83 feline urine samples were run using the u411 factory settings. Following comparisons with manual results, and evaluation for directional bias, adjustments to the reflectance values were made in the instrument's programming. An additional 183 canine and 95 feline samples were run using the adjusted settings. Total urine protein concentrations were measured in 48 samples and used to generate receiver operating characteristic curves for the protein test pad. RESULTS: Following adjustments in reflectance programming, concordance between u411 and manual results was increased by 17.7% for protein, 11.7% for ketones, and 4.5% for bilirubin. Concordances for pH, glucose, and blood were not substantially changed. Discordance for all analytes was ≤3%. Canine and feline samples had similar levels of discordance, though marginal concordance was higher in dogs for ketones, bilirubin, and blood. CONCLUSIONS: Adjustments to the reflectance programming of the Cobas u411 Analyzer improved concordance with manual results for canine and feline samples. This instrument has the potential to greatly increase both efficiency and consistency of urinalysis procedures in higher throughput veterinary diagnostic laboratories.

Stability and profiling of urinary microRNAs in healthy cats and cats with pyelonephritis or other urological conditions.

BACKGROUND: Specific biomarkers of pyelonephritis (PN) in cats are lacking. MicroRNAs (miRNAs) have diagnostic potential in human nephropathies. OBJECTIVES: To investigate the presence/stability of miRNAs in whole urine of cats and the discriminatory potential of selected urinary miRNAs for PN in cats. ANIMALS: Twelve healthy cats, 5 cats with PN, and 13 cats with chronic kidney disease (n = 5), subclinical bacteriuria (n = 3), and ureteral obstructions (n = 5) recruited from 2 companion animal hospitals. METHODS: Prospective case-control study. Expression profiles of 24 miRNAs were performed by quantitative PCR (qPCR). Effect of storage temperature (4°C [24 hours], -20°C, and -80°C) was determined for a subset of miRNAs in healthy cats. RESULTS: Urinary miR-4286, miR-30c, miR-204, miR4454, miR-21, miR-16, miR-191, and miR-30a were detected. For the majority of miRNAs tested, storage at 4°C and -20°C resulted in significantly lower miRNA yield compared to storage at -80°C (mean log2fold changes across miRNAs from -0.5 ± 0.4 SD to -1.20 ± 0.4 SD (4°C versus -80°C) and from -0.7 ± 0.2 SD to -1.20 ± 0.3 SD (-20°C versus -80°C)). Cats with PN had significantly upregulated miR-16 with a mean log2fold change of 1.0 ± 0.4 SD, compared with controls (-0.1 ± 0.2, P = .01) and other urological conditions (0.6 ± 0.3, P = .04). CONCLUSIONS: Upregulation of miR16 might be PN-specific, pathogen-specific (Escherichia coli), or both.