Effect of withholding food versus feeding on creatinine, symmetric dimethylarginine, cholesterol, triglycerides, and other biochemical analytes in 100 healthy dogs.

BACKGROUND: Withholding food is often recommended before collection of blood for routine biochemical analysis in dogs despite a paucity of evidence to support this requirement. OBJECTIVES: To compare measurements of selected biochemical analytes collected before and after feeding in clinically healthy dogs. ANIMALS: One hundred clinically healthy staff- and student-owned dogs weighing ≥15 kg. METHODS: Prospective observational study. Food was withheld from the dogs for 10-26 hours. Preprandial serum was collected, and then dogs were fed their usual food at an amount equivalent to at least 2/3 resting energy requirement (RER). Selected serum analytes were measured at 2-, 4-, 6-, and 8-hours postprandially. The proportion of postprandial values that exceeded either the reported allowable total error (TEa), or for symmetric dimethylarginine (SDMA), the reference change value (RCV), was determined. As neither TEa nor RCV is available for lipase, comparison was made to the high end of the reference interval (RI). RESULTS: The proportion of dogs with at least 1 postprandial measurement that exceeded the TEa or RCV was 92/100 for triglycerides, 66/100 for blood urea nitrogen (BUN), 46/100 for phosphorus, 17/100 for glucose, 9/100 for bilirubin, 5/100 for SDMA, 2/100 for creatinine, and 0/100 for cholesterol and albumin. Postprandial lipase never exceeded the RI in dogs with normal fasted lipase. CONCLUSIONS AND CLINICAL IMPORTANCE: Withholding food is generally not necessary before performing routine biochemical analysis in clinically healthy dogs. Withholding food might be helpful to limit variability in analytes impacted by feeding, such as triglycerides and phosphorus.

The Evaluation of the Diagnostic Value of a PCR Assay When Compared to a Serologic Micro-Agglutination Test for Canine Leptospirosis.

Objective: To evaluate PCR assay sensitivity and specificity compared to that of microscopic agglutination test (MAT) for diagnosis of canine leptospirosis. Electronic records search was performed to identify dogs with results for both PCR and MAT testing for leptospirosis. Methods: All dogs were clinically ill. Diagnosis of leptospirosis was defined as an unvaccinated dog with a positive MAT titer of ≥1:800 or a vaccinated dog or dog with an unknown vaccination status with a positive MAT titer of ≥1:1,600. Diagnosis of leptospirosis was excluded based on MAT titer <1:800 on both the initial and convalescent samples or an initial MAT titer <1:800 and an alternative definitive diagnosis. Results: Forty-nine samples (urine, n = 39; blood, n = 10) were evaluated. Leptospirosis was diagnosed in 17 dogs and excluded in 26 dogs. Urine PCR assay demonstrated sensitivity of 69.2%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 86.6%. Blood PCR assay demonstrated sensitivity of 25%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 25%. Overall PCR sensitivity was 52.4%, specificity was 100%, positive predictive value was 100%, and negative predictive value was 73.7%. Conclusions: PCR assay performed on urine or blood has high specificity and positive predictive value when compared to MAT for diagnosis of clinical canine leptospirosis. Sensitivity and negative predictive value are moderate to low, so PCR testing should be performed in conjunction with paired MAT testing for canine leptospirosis. Prior antibiotic therapy does not preclude the use of the PCR test.

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.

Prospective evaluation of complications associated with transesophageal echocardiography in dogs with congenital heart disease.

BACKGROUND: Transesophageal echocardiography (TEE) is useful in the assessment and procedural monitoring of congenital heart disease (CHD) with a relatively low complication rate in humans. OBJECTIVES: To evaluate the safety of TEE and report complications in dogs. ANIMALS: Forty client-owned dogs with CHD. METHODS: Prospective observational study including gastroesophagoscopy before and after TEE imaging. TEE was planned with a GE 6VT-D adult probe in dogs weighing ≥4 kg and a GE 10T-D microprobe alternating with an intracardiac echocardiography probe placed in the esophagus in dogs <4 kg. Difficulties with probe placement, probe interference and TEE probe imaging times were recorded. Dogs were monitored in the recovery period after TEE using an established nausea scoring system. RESULTS: New gastroesophageal abnormalities were identified after TEE in 4 dogs including 4 areas of mucosal damage involving <25% of the lower esophageal sphincter (n = 4) and 1 lesion at the heart base (n = 1) and were not attributed to longer imaging times or a specific probe. Lesions identified before TEE in 4 dogs remained unchanged after TEE. The 6VT-D probe could not be placed in 1 dog with enlarged tonsils, and it obstructed fluoroscopic views in 3 dogs. The probes did not compress any structures in dogs in which fluoroscopy was performed (n = 20). Four dogs had evidence to suggest nausea after the procedure. CONCLUSIONS AND CLINICAL IMPORTANCE: While major complications remain possible, complications in this study were mild and few in number. Dog size and probe characteristics are factors to consider when performing TEE.

Cytokine expression in feline allergic dermatitis and feline asthma.

BACKGROUND: The pathogenesis of feline allergic dermatitis (FAD) is unclear, with several differences from allergic dermatitis in dogs and humans. HYPOTHESIS/OBJECTIVES: To survey cytokine expression levels in healthy cats and cats affected with allergic dermatitis or asthma. ANIMALS: Formalin-fixed, paraffin-embedded skin biopsies from 22 cats with allergic dermatitis and 21 cats without allergic dermatitis were used for cutaneous assays. Serum was obtained from 17 healthy cats, 18 cats with allergic dermatitis, and 18 cats with a presumptive diagnosis of asthma. METHODS AND MATERIALS: Cutaneous mRNA expression was evaluated with quantitative PCR [interleukin (IL)-31 and IL-31 Receptor A] and RNA in situ hybridisation (ISH) [IL-5, IL-31, IL-31RA, IL-33 and Oncostatin M receptor (OSMR)-ß]. IL-31 protein concentrations were evaluated in serum with an enzyme-linked immunosorbent assay. Serum levels of 19 additional cytokines were evaluated using a Luminex panel. RESULTS: IL-31, IL-31RA, IL-5 and IL-33 mRNA expression were either expressed in low quantities or undetectable in most samples. By contrast, OSMR-ß expression was significantly higher in the skin of allergic versus healthy cats (P < 0.0001). Although serum IL-31 was detected in a larger number of cats with allergic dermatitis than healthy cats, and concentrations appeared to be higher in cats with allergies, this difference was not statistically significant. Cats affected by asthma also exhibited insignificantly higher concentrations of IL-31 in the serum. CONCLUSIONS AND CLINICAL RELEVANCE: Our results suggest that feline allergic diseases may exhibit different pathomechanisms from allergic diseases affecting other species. These findings are useful in guiding further therapeutic development toward targets that may have a role in the pathogenesis of feline allergic skin disease.

Multiple-Choice Questions in Small Animal Medicine: An Analysis of Cognitive Level and Structural Reliability, and the Impact of these Characteristics on Student Performance.

Students entering the final year of the veterinary curriculum need to integrate information and problem solve. Assessments used to document competency prior to entry to the clinical environment should ideally provide a reliable measurement of these essential skills. In this study, five internal medicine specialists evaluated the cognitive grade (CG) and structural integrity of 100 multiple-choice questions (MCQs) used to assess learning by third-year students at a United States (US) veterinary school. Questions in CG 1 tested factual recall and simple understanding; those in CG 2 required interpretation and analysis; CG 3 MCQs tested problem solving. The majority (53%) of questions could be answered correctly using only recall or simple understanding (CG 1); 12% of MCQs required problem solving (CG 3). Less than half of the questions (43%) were structurally sound. Overall student performance for the 3 CGs differed significantly (92% for CG 1 vs. 84% for CG 3; p = .03. Structural integrity did not appear to impact overall performance, with a median pass rate of 90% for flawless questions versus 86% for those with poor structural integrity (p = .314). There was a moderate positive correlation between individual student outcomes for flawless CG 1 versus CG 3 questions (rs = 0.471; p = < .001), although 13% of students failed to achieve an aggregate passing score (65%) on the CG 3 questions. These findings suggest that MCQ-based assessments may not adequately evaluate intended learning outcomes and that instructors may benefit from guidance and training for this issue.

Characteristics associated with bacterial growth in urine in 451 proteinuric dogs (2008-2018).

BACKGROUND: Urine cultures are frequently recommended to rule out infection as a postrenal cause of proteinuria. OBJECTIVE: Identify characteristics associated with bacterial growth in urine in proteinuric dogs. ANIMALS: Four hundred and fifty-one dogs admitted to a teaching hospital between January 2008 and January 2018 with urine protein-to-creatinine ratios (UPCs) >0.5. METHODS: Retrospective study included dogs with a UPC, urinalysis, and quantitative urine culture (QUC) performed within a 72-hour period by searching electronic records. Dogs with recent antimicrobial therapy, urine collected by methods other than cystocentesis, or UPC ≤0.5 were excluded. Signalment, comorbidities, serum BUN and creatinine concentrations, urinalysis findings, and QUC results were recorded. The association between these characteristics and presence of bacterial growth in urine was assessed by univariable and multivariable analysis. RESULTS: Thirty of four hundred fifty-one dogs (6.7%) had bacterial growth in urine. Of these, 18 (60.0%) had active urine sediment. Bacterial growth in urine was associated with pyuria (odd ratio [OR] 25.1, 95% confidence interval [CI] 7.9-79.6, P < .001), bacteriuria (OR 11.1, 95% CI 3.2-39.1, P < .001), and lower urinary tract disease (OR 6.7, 95% CI 1.9-23.0; P = .0028). If QUC was prompted based on these criteria, 8/451 (1.8%) of proteinuric dogs would have had undetected bacterial growth. CONCLUSIONS AND CLINICAL IMPORTANCE: The proportion of proteinuric dogs with both inactive urine sediment and bacterial growth in urine was low, suggesting that QUC might not be necessary in the evaluation of all proteinuric dogs. An active urine sediment or lower urinary tract disease should prompt QUC for proteinuric dogs.

Evaluation of a low-technology system to obtain morphological and mobility trial measurements in dogs and investigation of potential predictors of canine mobility.

OBJECTIVE: To develop a low-technology system that can be used by dog owners to obtain morphological and mobility measurements in companion dogs as candidate components of an eventual canine frailty scale. ANIMALS: 57 adult (≥ 1-year-old) dogs enrolled by 43 owners. PROCEDURES: Morphological measurements of dogs were performed by investigators and dog owners. Dogs participated in timed in-clinic mobility trials across a flat surface (on-leash trial with the owner, on-leash trial with the investigator, and off-leash trial) and on stairs; each trial was repeated 3 times. Owners were asked to conduct a second stair trial at home 2 weeks later. Agreement between owner- and investigator-obtained measurements was assessed with Shrout-Fleiss intraclass correlation coefficients and paired t tests. Age, quartile of projected percentage of mean life span attained (adjusted for body weight), and height were evaluated as predictors of speed and stride length in mobility trials with linear regression and Spearman rank correlation analysis. RESULTS: Agreement between owner- and investigator-obtained morphological measurements was strong. Age was a weak but significant predictor of decreased dog speed in mobility trials (adjusted R2, 0.10 to 0.23). Speed decreased significantly with increasing quartile of projected life span attained. A linear regression model that included height and age predicted dog speed better than models with age or height alone. CONCLUSIONS AND CLINICAL RELEVANCE: Morphological and mobility trial measurements can be obtained by dog owners with minimal training. Low-technology measurements of mobility trial speed offer potential as components in a future scoring scale for canine frailty.

Comparison of the performance of the IDEXX SediVue Dx® with manual microscopy for the detection of cells and 2 crystal types in canine and feline urine.

BACKGROUND: Microscopic evaluation of urine is inconsistently performed in veterinary clinics. The IDEXX SediVue Dx® Urine Sediment Analyzer (SediVue) recently was introduced for automated analysis of canine and feline urine and may facilitate performance of urinalyses in practice. OBJECTIVE: Compare the performance of the SediVue with manual microscopy for detecting clinically relevant numbers of cells and 2 crystal types. SAMPLES: Five-hundred thirty urine samples (82% canine, 18% feline). METHODS: For SediVue analysis (software versions [SW] 1.0.0.0 and 1.0.1.3), uncentrifuged urine was pipetted into a cartridge. Images were captured and processed using a convolutional neural network algorithm. For manual microscopy, urine was centrifuged to obtain sediment. To determine sensitivity and specificity of the SediVue compared with manual microscopy, thresholds were set at ≥5/high power field (hpf) for red blood cells (RBC) and white blood cells (WBC) and ≥1/hpf for squamous epithelial cells (sqEPI), non-squamous epithelial cells (nsEPI), struvite crystals (STR), and calcium oxalate dihydrate crystals (CaOx Di). RESULTS: The sensitivity of the SediVue (SW1.0.1.3) was 85%-90% for the detection of RBC, WBC, and STR; 75% for CaOx Di; 71% for nsEPI; and 33% for sqEPI. Specificity was 99% for sqEPI and CaOx Di; 87%-90% for RBC, WBC, and nsEPI; and 84% for STR. Compared to SW1.0.0.0, SW1.0.1.3 had increased sensitivity but decreased specificity. Performance was similar for canine versus feline and fresh versus stored urine samples. CONCLUSIONS AND CLINICAL IMPORTANCE: The SediVue exhibits good agreement with manual microscopy for the detection of most formed elements evaluated, but improvement is needed for epithelial cells.

Toxicosis associated with ingestion of quick-dissolve granulated chlorine in a dog.

CASE DESCRIPTION: A dog was referred for treatment after ingestion of quick-dissolve chlorine granules intended for use in a swimming pool. CLINICAL FINDINGS: At evaluation 18 hours after ingestion of the granules, the dog had tachypnea, signs of depression, approximately 5% dehydration, oral mucositis, and a productive cough. Increased respiratory tract sounds and wheezes were ausculted in all lung fields. Complete blood count revealed erythrocytosis and lymphopenia. Serum biochemical analyses revealed mildly high activities of hepatic enzymes and creatine kinase. Arterial blood gas concentrations were consistent with hypoxemia and hyperventilation. Thoracic radiography revealed widespread pulmonary alveolar infiltrates predominantly affecting the ventral portions of both lungs, consistent with noncardiogenic pulmonary edema secondary to aspiration of the granulated chlorine. TREATMENT AND OUTCOME: Initial treatment included IV administration of an electrolyte solution with supplemental KCl, ranitidine, furosemide, cefotaxime, buprenorphine, and supplemental oxygen. Subsequent treatment included administration of meloxicam and an endoscopically placed percutaneous gastrostomy tube. Endoscopic examination revealed esophagitis and mild gastritis; therefore, metoclopramide and sucralfate were also administered. Fifteen days later, the gastrostomy tube was removed prior to discharge; endoscopic examination revealed grossly normal esophageal and gastric mucosa, and thoracic radiography revealed complete resolution of the lung lesions. CLINICAL RELEVANCE: Although ingestion of granulated chlorine is rare in veterinary patients, the resulting disease processes are common and can be treated successfully.

Effect of levothyroxine administration on hemostatic analytes in Doberman Pinschers with von Willebrand disease.

Levothyroxine administration has been suggested to be an effective treatment for canine von Willebrand disease (vWd), but evidence supporting this treatment is lacking. Effects of levothyroxine administration were evaluated in 8 euthyroid Doberman Pinschers with plasma von Willebrand factor (vWf) concentrations < 15%, characteristic of type 1 vWd. Levothyroxine (0.04 mg/kg PO q12h) and placebo were administered for 30 days in a 2-period, 2-treatment, double-blinded, crossover design with a 30-day washout period between treatments. Buccal mucosal bleeding time (BMBT), plasma vWf concentration (vWf: Ag), vWf collagen binding activity (vWf:CBA), factor VIII coagulant activity (FVIII:C), and serum concentrations of total thyroxine (T4), free thyroxine (fT4), 3,5,3'-triiodothyronine (T3), and thyroid-stimulating hormone (TSH) were measured on days 0, 2, and 30 of each treatment period. The 8 dogs (1 male, 7 females) had markedly low plasma vWf:Ag (mean, 8.9%; reference range, 70-180%) and vWf:CBA (mean, 11.1%; reference range, >70%). Response to placebo versus levothyroxine treatment was not significantly different between groups at day 0, 2, or 30 for BMBT, vWf:Ag, vWf:CBA, and FVIII:C. Serum T4, fT4, and T3 concentrations were significantly higher and serum TSH significantly lower in the levothyroxine-treated group than in the placebo group at days 2 and 30. Administration of levothyroxine at 0.04 mg/kg caused laboratory evidence of hyperthyroidism but did not affect plasma FVIII:C and vWf:Ag concentrations or vWf-dependent collagen binding and BMBT. The results of this study failed to identify a direct action of levothyroxine supplementation on plasma vWf concentration or activity in euthyroid Doberman Pinschers with vWd.

Systemic candidiasis in a dog.

Candida albicans is a common cause of nosocomial infections in humans, but there are few reports of systemic candidiasis in dogs. This report describes an 11-year-old spayed female Scottish Terrier with systemic candidiasis. The diagnosis was made on the basis of results of microbiologic culture of specimens from urine and venous catheters and histologic examination of tissues obtained post mortem. Factors that predisposed the dog of this report to systemic candidiasis included diabetes mellitus, corticosteroid and broad-spectrum antimicrobial administration, venous and urinary catheterization, and administration of nutrition parenterally. The development of pyrexia and leukocytosis in dogs with risk factors that predispose to Candida spp infections warrants evaluation via microbial culture of specimens from urine and vascular catheters used in those dogs.