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

Comparison of cystocentesis versus home sampling to determine urinary protein: Creatinine ratio and urine specific gravity in cats

BACKGROUND

Urinalysis is necessary for the diagnostic evaluation of chronic kidney disease in cats. Performing cystocentesis is not always feasible, but data comparing urine obtained by cystocentesis in the clinic with voided samples collected at home are lacking in cats.

OBJECTIVES

To compare urinary protein:creatinine ratio (UPC) and urine specific gravity (USG) and to detect clinically relevant changes in proteinuria substage or urine concentration between urine collected at home and in-clinic by cystocentesis in cats.

ANIMALS

Ninety-two healthy and diseased client-owned cats.

METHODS

Prospective study. Owners collected voided urine at home and within 1 to 15 hours, cystocentesis was performed in the clinic.

RESULTS

In a subset of motivated owners, 55% succeeded in collecting urine at home. Overall, UPC was higher (mean ±SD difference = 0.09 ±0.22; P < .001) and USG was lower (mean ±SD difference = -0.006 ±0.009; P < .001) in cystocentesis samples than in voided urine. Substantial agreement existed between sampling methods for UPC (weighted к = 0.68) and USG (к = 0.64) categories. A different proteinuria substage (UPC < 0.2, 0.2-0.4, >0.4) was present in paired urine samples from 28% of cats. In 18% of cats, urine concentrating ability (USG < or ≥1.035) differed between both samples.

CONCLUSIONS AND CLINICAL IMPORTANCE

Home sampling of urine is a valid alternative to cystocentesis in cats. However, because clinically relevant differences in UPC and USG were present in 28% and 18% of cats, respectively, by the same collection method for monitoring each cat is advised.

2023 AAHA Selected Endocrinopathies of Dogs and Cats Guidelines

Canine and feline endocrinopathies reflect an endocrine gland disease or dysfunction with resulting hormonal abnormali ties that can variably affect the patient's wellbeing, quality of life, and life expectancy. These guidelines provide consensus recommendations for diagnosis and treatment of four canine and feline endocrinopathies commonly encountered in clini cal practice: canine hypothyroidism, canine hypercortisolism (Cushing's syndrome), canine hypoadrenocorticism (Addi son's disease), and feline hyperthyroidism. To aid the general practitioner in navigating these common diseases, a stepwise diagnosis and treatment algorithm and relevant background information is provided for managing each of these diseases. The guidelines also describe, in lesser detail, the diagnosis and treatment of three relatively less common endo crinopathies of cats: feline hyperaldosteronism, feline hypothyroidism, and feline hyperadrenocorticism. Additionally, the guidelines present tips on effective veterinary team utilization and client communication when discussing endocrine cases.

First study on stress evaluation and reduction in hospitalized cats after neutering surgery

Background and Aim:

In Thailand, domestic cats are the most common companion animal, and many are admitted to veterinary clinics for neutering surgery; however, such environment can induce stress. This is the first study to evaluate stress in hospitalized cats after neutering surgery using cat stress score (CSS) and salivary cortisol levels, including the impact of providing a hiding box (B) and/or administering a pheromone product to reduce stress.

Materials and Methods:

The study design was based on a randomized controlled clinical trial. A total of 80 domestic cats undergoing routine neutering surgery were assessed for their behavioral demeanor scoring system (DSS) as friendly (DSS1) and aggressive (DSS2) based on a DSS. During admission, the cats were randomly allocated to single standard cages with one of the following treatments: (B), feline facial pheromone (P), a combination of hiding box and the pheromone (BP), or no additional enrichment (C). Cat stress score, food intake, and hide-seeking behavior were recorded. The cortisol enzyme-linked immunosorbent assay kit was used to assess the salivary cortisol level.

Results:

On the 1^st day of admission, aggressive cats had a significantly higher CSS (4.16 ± 0.29) than friendly cats (3.27 ± 0.16). Both demeanor cat groups showed statistically significant reductions in stress levels earlier than the control group after providing the enrichments. Saliva cortisol measurements ranged from 0.24 to 0.66 ng/mL. No statistical differences in cortisol levels were observed between the 1^st day and other days of admission. In contrast, no differences in food intake and hide-seeking behavior were seen within each group during the same period.

Conclusion:

Results suggested that stress and stress responses in cats depended on behavioral demeanor. The provision of enrichment, including hiding box and feline facial pheromone in singly housed caging reduced stress, especially in aggressive cats. However, salivary cortisol analysis, food intake, and hide-seeking behavior were ineffective for assessing stress in cats after neutering surgery.

Social roles influence cortisol levels in captive Livingstone's fruit bats (Pteropus livingstonii)

A critical component of conserving and housing species ex situ is an explicit scientific understanding of the physiological underpinnings of their welfare. Cortisol has been repeatedly linked to stress, and therefore used as an indicator of welfare for many species. In order to measure cortisol in the Livingstone's fruit bat (Pteropus livingstonii; a critically endangered keystone species) without disturbing the captive population, we have developed and validated a non-invasive, novel hormone extraction procedure and faecal glucocorticoid assay. A total of 92 faecal samples, 73 from the P. livingstonii breeding colony at Jersey Zoo, Channel Islands and 19 samples from P. livingstonii housed at Bristol Zoological Gardens, UK, have been collected and analyzed. Mixed-effect modelling of the influence of physiological state variables on cortisol concentration revealed that lactating females had higher cortisol levels than non-lactating females, indicating that our assay is measuring biologically relevant hormone concentrations. Males and older bats also had higher cortisol than non-lactating females and younger individuals. Further analysis applied social network methodology to compare the cortisol levels of bats with different social roles. We found that individuals that linked social groups possessed higher than average cortisol levels and conversely, individuals with high-quality, positive relationships had lower cortisol levels. These results demonstrate, for the first time in a bat species, social mediation of stress hormones. Lastly, the frequency of vocalisation was found to positively correlate with cortisol concentration in males, suggesting that this behaviour may be used by animal management as a visual indicator of a bat's hormonal status. Hence, this research has provided unique insights and empirical scientific knowledge regarding the relationship between the physiology and social behaviour of P. livingstonii, therefore allowing for recommendations to be made to optimise bat welfare at the individual level.

Investigation of the urine cortisol to creatinine ratio for the diagnosis of hypoadrenocorticism in dogs

OBJECTIVE

To evaluate the urine cortisol-to-creatinine ratio (UCCR) for the diagnosis of hypoadrenocorticism (HA) in dogs and to determine whether the method of urine cortisol measurement affects results.

ANIMALS

41 dogs with naturally occurring HA and 107 dogs with nonadrenal illness.

PROCEDURES

Urine samples were prospectively collected from dogs undergoing testing for HA. Urine cortisol concentrations were measured at a veterinary diagnostic laboratory using either a radioimmunoassay (RIA) or a chemiluminescent immunoassay (CLIA). Receiver operating characteristic (ROC) curves were constructed to assess UCCR performance by both methods for HA diagnosis. Sensitivities, specificities, accuracies, and predictive values were calculated for various cutpoints.

RESULTS

The areas under the ROC curves for UCCR diagnosis of HA were 0.99 (95% CI, 0.98 to 1.00) and 1.00 (95% CI, 1.00 to 1.00) when urine cortisol was determined by RIA and CLIA, respectively. An RIA UCCR of ≤ 2 was 97.2% sensitive, 93.6% specific, and 94.7% accurate for HA diagnosis, whereas a CLIA UCCR of ≤ 10 was 100% sensitive, specific, and accurate. An RIA UCCR > 4 and a CLIA UCCR of > 10 had negative predictive values of 100%.

CLINICAL RELEVANCE

The UCCR was an accurate diagnostic test for HA in this study population, although equivocal results are possible. Case characteristics, method of cortisol measurement, and laboratory-specific cutpoints must be considered when interpreting results.

Urinary cortisol-creatinine ratio in dogs with hypoadrenocorticism

Background

Basal serum cortisol (BSC) ≥2 μg/dL (>55 nmol/L) has high sensitivity but low specificity for hypoadrenocorticism (HA).

Objective

To determine whether the urinary corticoid:creatinine ratio (UCCR) can be used to differentiate dogs with HA from healthy dogs and those with diseases mimicking HA (DMHA).

Animals

Nineteen healthy dogs, 18 dogs with DMHA, and 10 dogs with HA.

Methods

Retrospective study. The UCCR was determined on urine samples from healthy dogs, dogs with DMHA, and dogs with HA. The diagnostic performance of the UCCR was assessed based on receiver operating characteristics (ROC) curves, calculating the area under the ROC curve.

Results

The UCCR was significantly lower in dogs with HA (0.65 × 10⁻⁶; range, 0.33‐1.22 × 10⁻⁶) as compared to healthy dogs (3.38 × 10⁻⁶; range, 1.11‐17.32 × 10⁻⁶) and those with DMHA (10.28 × 10⁻⁶; range, 2.46‐78.65 × 10⁻⁶) (P < .0001). There was no overlap between dogs with HA and dogs with DMHA. In contrast, 1 healthy dog had a UCCR value in the range of dogs with HA. The area under the ROC curve was 0.99. A UCCR cut‐off value of <1.4 yielded 100% sensitivity and 97.3% specificity in diagnosing HA.

Conclusions and Clinical Importance

The UCCR seems to be a valuable and reliable screening test for HA in dogs. The greatest advantage of this test is the need for only a single urine sample.

Potential Acute Renal Injury in Sheep with Bluetongue Serotype 4

Bluetongue is a vector-borne disease with epidemic potential. Recently, outbreaks of Bluetongue were reported across Greece, caused by the Bluetongue virus (BTV) serotype 4. Regarding its pathogenesis, BTV infection involves various target organs with limited data referring to the kidneys. The objective of this study was to identify the possible impact of BTV infection on kidneys using common renal biomarkers. Urine and blood samples collected from 30 sheep with clinical signs of bluetongue (BTV sheep) and 30 clinically healthy sheep (normal sheep) from the same farms were finally selected and included in the study from an initial population of 47 sheep per group, based on the absence of active urine sediment. Complete urinalysis was performed and urine protein to creatinine ratio (UPC) and urine gamma-glutamyl transferase to creatinine (UGGTC) ratio were determined. Blood urea nitrogen (BUN), creatinine, total proteins, albumin (ALB), and inorganic phosphate (P) were determined in serum samples. UPC and UGGTC were significantly higher (p < 0.05) in BTV sheep compared to normal, whereas urine specific gravity (USG) was significantly lower (p < 0.05). Cylindruria was also detected in BTV sheep, and absence of azotemia in BTV and normal sheep. All these findings are indicative of renal tubular injury and/or dysfunction and suggestive of an association between BTV infection and acute damage of renal tissue.

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

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.