Comparison between Urine Protein: Creatinine Ratios of Samples Obtained from Dogs in Home and Hospital Settings

Background Recently, urine protein:creatinine ratios (UPC) were shown to be lower in urine samples from dogs collected at home (AH) as compared to those collected in hospital (IH). Stress‐inducing procedures and travel to the hospital have been hypothesized to cause prerenal proteinuria. Objectives Evaluate patient stress using urine cortisol:creatinine ratios (UCCr) and correlate UCCr to UPC in urine samples obtained AH and IH. Animals Thirty‐six healthy, client‐owned dogs. Methods Prospective, non‐masked study. Two voided urine samples were obtained (AH and IH). Complete urinalysis as well as UPC and UCCr were performed. Clients graded their dogs' stress level AH, in transport, and IH. Results The UCCr was significantly higher in IH samples than in AH samples (P < .0001), but UPC was not significantly different between AH and IH urine samples (P = .14). In all samples and in both collection settings, UCCr was not significantly correlated with UPC. Travel time and time IH were not correlated with change in UCCr or UPC. In 8 dogs with borderline or overt proteinuria, no significant difference was found in UPC between settings, but UCCr was significantly higher in IH samples. Conclusions and Clinical Importance The UPC was not higher when measured in urine samples collected IH compared to AH. Dogs had higher UCCr IH, but UCCr was not associated with UPC. Stress, as estimated by UCCr, did not affect proteinuria. Further evidence is needed to support the claim that stress may result in proteinuria in healthy dogs.

Section: Discussioncontrasting

confidence: 81%

“…In particular, pathologic renal proteinuria is considered a marker for increased risk for progression of kidney disease and prompts the need for intervention by practitioners. However, other nonrenal factors, such as stress, have been hypothesized to cause transient, nonpathologic prerenal proteinuria in dogs …”

Section: Introductionmentioning

confidence: 99%

Urine cortisol‐creatinine and protein‐creatinine ratios in urine samples from healthy dogs collected at home and in hospital

Citron¹,

Weinstein

Littman

et al. 2020

“…The most apparent explanation for this observation is that UPC results were significantly higher on the samples collected in‐hospital than in those collected at home, particularly for dogs with UPC >4. A previous study showed that the UPC of a sample obtained in the hospital typically is higher than the UPC of a sample obtained at home. Our study had evaluated the UPC from dogs presented to their hospital for a variety of reasons, and thus was not specifically designed to evaluate proteinuric dogs.…”

Section: Discussionmentioning

confidence: 92%

Comparison of Single, Averaged, and Pooled Urine Protein:Creatinine Ratios in Proteinuric Dogs Undergoing Medical Treatment

Shropshire

Quimby

Cerda

2017

BackgroundMonitoring urine protein:creatinine ratios (UPC) in dogs with protein‐losing nephropathy (PLN) is challenging because of day‐to‐day variation in UPC results.Hypothesis/ObjectivesDetermine whether single, averaged, or pooled samples from PLN dogs receiving medical treatment yield comparable UPCs, regardless of degree of proteinuria.AnimalsTwenty‐five client‐owned PLN dogs receiving medical treatment.Methods UPC ratios were prospectively measured in each dog utilizing 3 methods: single in‐hospital sample (day 3), average sample (days 1–3), and pooled sample (equal pooling of urine from days 1–3). Bland‐Altman analysis was performed to evaluate agreement between methods for all dogs, as well as in subgroups of dogs (UPC ≤4 or UPC >4).ResultsFor all dogs, Bland‐Altman log‐transformed 95% limits of agreement were −0.07–0.18 (single versus pooled UPC), −0.06–0.16 (single versus average UPC), and −0.06–0.04 (pooled versus average UPC). For dogs with UPC ≤4, Bland‐Altman 95% limits of agreement were −0.42–0.82 (single versus pooled UPC), −0.38–0.76 (single versus average UPC), and −0.27–0.25 (pooled versus average UPC). For dogs with UPC >4, Bland‐Altman 95% limits of agreement were −0.17–2.4 (single versus pooled UPC), −0.40–2.2 (single versus average UPC), and −0.85–0.43 (pooled versus average UPC).Conclusions and Clinical Importance UPC ratios from all methods were comparable in PLN dogs receiving medical treatment. In PLN dogs with UPC >4, more variability between methods exists likely because of higher in‐hospital results, but whether this finding is clinically relevant is unknown.

“…Fifth, no standardized containers were used for collection of free catch urine samples. Protein binding to hydrophilic surfaces is mainly believed to be important with very low concentrations of albumin (microalbuminuria) . Therefore, it seems unlikely to have significantly affected our UPC measurements, although falsely decreased UPC cannot be excluded .…”

Section: Discussionmentioning

confidence: 98%

“…Protein binding to hydrophilic surfaces is mainly believed to be important with very low concentrations of albumin (microalbuminuria) . Therefore, it seems unlikely to have significantly affected our UPC measurements, although falsely decreased UPC cannot be excluded . Sixth, urinalysis could not be performed for all free catch samples within 60 minutes after collection.…”

Section: Discussionmentioning

confidence: 99%

Proteinuria in Apparently Healthy Elderly Dogs: Persistency and Comparison Between Free Catch and Cystocentesis Urine

Marynissen

Willems

Paepe

et al. 2016

BackgroundUp to 25% of elderly humans have proteinuria, often associated with underlying lesions. Data concerning the presence of proteinuria in elderly dogs is scarce.ObjectivesTo describe the presence and persistence of proteinuria and to compare urinary protein : creatinine ratio (UPC) between free catch and cystocentesis urine samples in apparently healthy elderly dogs.AnimalsHundred apparently healthy elderly dogs.MethodsProspective study. Owners of 100 elderly dogs were asked to collect 2 free catch urine samples. Dogs were considered healthy based on owner's perception and an age chart, based on ideal bodyweight, was used to define dogs as senior or geriatric. UPC of urine collected by free catch and cystocentesis were compared. Overt proteinuria and borderline proteinuria were defined as UPC >0.5 and between 0.2 and 0.5, respectively, if examination of sediment did not explain proteinuria. Proteinuria was considered persistent if present at both sampling times.ResultsAt baseline, 71 owners succeeded in collecting urine. Eleven percent of dogs had overt proteinuria, 14% were borderline proteinuric, and 75% nonproteinuric. Thirty‐seven repeated urine samples, with a median time interval of 31 days (range 10–90), were available. Nineteen percent of dogs had a persistently increased UPC (>0.2), with persistent overt proteinuria present in 8%. A strong correlation (ρ = 0.88) was found between UPC of urine collected by free catch and cystocentesis.Conclusions and Clinical ImportanceAs 19% of study dogs had persistent proteinuria, our findings emphasize that measurement of proteinuria should be part of geriatric health screening. For UPC in dogs, free catch urine provides a good alternative to cystocentesis.