Serum pancreatic lipase immunoreactivity in sick dogs after chronic administration of supraphysiologic doses of glucocorticoids.

BACKGROUND: Glucocorticoids (GC) are commonly used for a long term to treat a multitude of immune-mediated, inflammatory, and neoplastic diseases in dogs. Conflicting results of published studies on the effects of exogenous and endogenous GCs on serum canine pancreatic lipase immunoreactivity (cPLI) raise the question of whether cPLI concentrations can be reliably interpreted in patients receiving GCs. OBJECTIVE: We sought to determine the effect of long-term GC administration at supraphysiologic doses on serum cPLI concentrations in sick dogs. METHODS: Serum samples were collected from 35 client-owned dogs. Dogs were administered prednisone at a dose of ≥0.5 mg/kg per day for ≥3 weeks. Serum cPLI was measured prior to the initiation and after ≥3 weeks of GC therapy. RESULTS: There was a significant increase in serum cPLI between baseline (median 101 µg/L; range 30-1997 µg/L) and following the administration of ≥0.5 mg/kg/day of prednisone (median 173 µg/L; range 30-2000 µg/L) in dogs (P = 0.025). However, the median change was small (31 µg/L). There was no suspicion of pancreatitis in any of the dogs. Diagnostic interpretation changed in 6/35 dogs, with no apparent dose-response relationship. CONCLUSIONS: There was a statistically significant difference from baseline in serum cPLI measurements in sick dogs receiving long-term prednisone. Although the change was small and often clinically insignificant, it could pose a clinical interpretation dilemma in some dogs. It is unknown whether these observations are coincidental due to subclinical pancreatitis or caused by another effect of GCs on pancreatic acinar cells.

Untargeted metabolomic profiling of urine from healthy dogs and dogs with chronic hepatic disease.

Chronic hepatic disease can present a diagnostic challenge with different etiologies being associated with similar clinical and laboratory findings. The histopathological assessment of a liver biopsy specimen is usually required in order to make a definitive diagnosis and the availability of non-invasive prognostic biomarkers is limited. The emerging science of metabolomics is used to detect changes in endogenous low molecular weight metabolites in biological samples and offers the possibility of identifying noninvasive markers of disease. The objective of this study was to investigate differences in the urine metabolome between healthy dogs, dogs with chronic hepatitis, dogs with hepatocellular carcinoma, and dogs with a congenital portosystemic shunt. Stored urine samples from 10 healthy dogs, 10 dogs with chronic hepatitis, 6 dogs with hepatocellular carcinoma, and 5 dogs with a congenital portosystemic shunt were analyzed. The urine metabolome was analyzed by gas chromatography-quadrupole time of flight mass spectrometry and 220 known metabolites were identified. Principal component analysis and heat dendrogram plots of the metabolomics data showed clustering between groups. Random forest analysis showed differences in the abundance of various metabolites including putrescine, gluconic acid, sorbitol, and valine. Based on univariate statistics, 37 metabolites were significantly different between groups. In, conclusion, the urine metabolome varies between healthy dogs, dogs with chronic hepatitis, dogs with hepatocellular carcinoma, and dogs with a congenital portosystemic shunt. Further targeted assessment of these metabolites is needed to assess their diagnostic utility.

Longitudinal assessment of microbial dysbiosis, fecal unconjugated bile acid concentrations, and disease activity in dogs with steroid-responsive chronic inflammatory enteropathy.

BACKGROUND: Mounting evidence from human studies suggests that bile acid dysmetabolism might play a role in various human chronic gastrointestinal diseases. It is unknown whether fecal bile acid dysmetabolism occurs in dogs with chronic inflammatory enteropathy (CE). OBJECTIVE: To assess microbial dysbiosis, fecal unconjugated bile acids (fUBA), and disease activity in dogs with steroid-responsive CE. ANIMALS: Twenty-four healthy control dogs and 23 dogs with steroid-responsive CE. METHODS: In this retrospective study, fUBA were measured and analyzed. Fecal microbiota were assessed using a dysbiosis index. The canine inflammatory bowel disease activity index was used to evaluate remission of clinical signs. This was a multi-institutional study where dogs with steroid-responsive CE were evaluated over time. RESULTS: The dysbiosis index was increased in dogs with CE (median, 2.5; range, -6.2 to 6.5) at baseline compared with healthy dogs (median, -4.5; range, -6.5 to -2.6; P = .002) but did not change in dogs with CE over time. Secondary fUBA were decreased in dogs with CE (median, 29%; range, 1%-99%) compared with healthy dogs (median, 88%; 4%-96%; P = .049). The percent of secondary fUBA in dogs with CE increased from baseline values (median, 28%; range, 1%-99%) after 2-3 months of treatment (median, 94%; range, 1%-99%; P = 0.0183). CONCLUSIONS AND CLINICAL IMPORTANCE: These findings suggest that corticosteroids regulate fecal bile acids in dogs with CE. Additionally, resolution of clinical activity index in dogs with therapeutically managed CE and bile acid dysmetabolism are likely correlated. However, subclinical disease (i.e., microbial dysbiosis) can persist in dogs with steroid-responsive CE.

Development, validation, and application of a liquid chromatography-tandem mass spectrometry method for quantitative determination of trans-4-hydroxy-l-proline concentration in the serum of dogs with chronic hepatitis.

OBJECTIVE: To develop and analytically validate a liquid chromatography-tandem mass spectrometry method for measurement of endogenous trans-4-hydroxy-l-proline concentrations in canine serum and to assess serum trans-4-hydroxy-l-proline concentrations in dogs with chronic hepatitis. SAMPLE: Serum samples obtained from 20 dogs with histopathologically confirmed chronic hepatitis and 20 healthy control dogs. PROCEDURES: A liquid chromatography-tandem mass spectrometry method for quantification of trans-4-hydroxy-l-proline concentration was developed and assessed for analytic sensitivity, linearity, accuracy, precision, and reproducibility. Serum concentration of trans-4-hydroxy-l-proline in dogs with chronic hepatitis and healthy control dogs was measured. RESULTS: Observed-to-expected ratios for dilutional parallelism ranged from 72.7% to 111.5% (mean ± SD, 91.3 ± 19.6%). Intra-assay and interassay coefficients of variation ranged from 2.1% to 3.0% and 3.2% to 5.3%, respectively. Relative error ranged from -2.3% to 7.8%. Trans-4-hydroxy-l-proline concentrations were significantly lower in serum obtained from dogs with chronic hepatitis (median, 0.24 ng/mL; range, 0.06 to 1.84 ng/mL) than in serum obtained from healthy control dogs (median, 0.78 ng/mL; range, 0.14 to 4.90 ng/mL). CONCLUSIONS AND CLINICAL RELEVANCE: The method described here for the quantification of trans-4-hydroxy-l-proline concentration in canine serum was found to be sensitive, specific, precise, accurate, and reproducible. Dogs with chronic hepatitis had significantly lower serum trans-4-hydroxy-l-proline concentrations than did healthy control dogs, possibly as a result of altered hepatic metabolism of amino acids.

Untargeted metabolomic profiling of serum from dogs with chronic hepatic disease.

BACKGROUND: Chronic hepatopathies present a diagnostic challenge, with different diseases being associated with similar clinical and laboratory findings. Characterization of dogs with chronic hepatopathies can be difficult and require costly diagnostic procedures such as acquisition of a liver biopsy specimen. Noninvasive and inexpensive biomarkers that reliably characterize chronic hepatopathies such as chronic hepatitis or a congenital portosystemic vascular anomaly may decrease the need for costly or invasive diagnostic testing and guide novel therapeutic interventions. OBJECTIVE: To investigate differences in the serum metabolome among healthy dogs, dogs with congenital portosystemic shunts, and dogs with chronic hepatitis. ANIMALS: Stored serum samples from 12 healthy dogs, 10 dogs with congenital portosystemic shunts, and 6 dogs with chronic hepatitis were analyzed. METHODS: The serum metabolome was analyzed with an untargeted metabolomics approach using gas chromatography-quadrupole time of flight mass spectrometry. RESULTS: Principal component analysis and heat dendrogram plots of the metabolomics data showed clustering among individuals in each group. Random forest analysis showed differences in the abundance of various metabolites including increased aromatic amino acids and xylitol in dogs with congenital portosystemic shunts. Based on the univariate statistics, 50 metabolites were significantly different among groups. CONCLUSIONS AND CLINICAL IMPORTANCE: The serum metabolome varies among healthy dogs, dogs with congenital portosystemic shunts, and dogs with chronic hepatitis. Statistical analysis identified several metabolites that differentiated healthy dogs from dogs with vascular or parenchymal liver disease. Further targeted assessment of these metabolites is needed to confirm their diagnostic reliability.

Proteomic analysis of liver tissue from dogs with chronic hepatitis.

Chronic hepatitis is the most common hepatic disease in dogs. Copper accumulation is an important cause of chronic hepatitis in dogs; however, the etiology in most dogs cannot be determined. Clinical signs of chronic hepatitis are often non-specific; therefore, this disease is frequently diagnosed in an advanced stage that makes successful intervention less likely. Early diagnosis of chronic hepatitis in dogs would thus be beneficial. The identification of proteins that are differentially expressed in dogs with chronic hepatitis could contribute to the development of novel diagnostic markers for this disease and provide insight into its pathogenesis. The objective of this study was to identify novel proteins that are differentially expressed in the liver of dogs with chronic hepatitis. Hepatic tissue was collected from 8 healthy dogs during ovariohysterectomy and from 8 dogs with histologically confirmed chronic hepatitis. The proteome of the liver samples was extracted by mechanical disruption and detergent-based cell lysis and differentially labeled prior to analysis by 2-dimensional fluorescence difference gel electrophoresis. Spots with an absolute fold change value > 2.0 were selected for further analysis. Protein identification was achieved by nanoflow liquid chromatography tandem mass spectrometry. Differential expression of select proteins was validated by Western blot. Five protein spots were differentially expressed between patients with chronic hepatitis and healthy control dogs. From these 5 protein spots 11 proteins were identified. Differential expression of cytokeratin 18 and annexin 5 were confirmed by Western blot analysis. Differential protein expression was shown between dogs with chronic hepatitis and healthy control dogs. Upregulation of cytokeratin 18 in chronic hepatitis may suggest increased hepatocellular apoptosis and necrosis, whereas upregulation of annexin 5A suggests increased hepatocellular apoptosis. Further studies are needed to determine whether either protein has diagnostic utility.

Laboratory Evaluation of the Liver.

Laboratory evaluation of the hepatobiliary system has an important role in the diagnosis, monitoring, and assessment of patients with hepatobiliary diseases. Serum liver enzyme activities can be divided into markers of hepatocellular injury and cholestasis. Liver function can be assessed in several ways, including assessment of synthetic capacity, measurement of ammonia, and measurement of bile acids. It is essential to have an understanding of the performance characteristics and limitations of these tests in order to use them appropriately. This article reviews the laboratory parameters commonly used to aid diagnosing hepatobiliary disorders in dogs and cats.

Clinical findings, diagnostics and outcome in 33 cats with adrenal neoplasia (2002-2013).

OBJECTIVES: The objective of this retrospective study was to describe the clinical signs and diagnostic findings in cats with histopathologically confirmed adrenal neoplasms, and to assess correlations with survival data. METHODS: Study data were acquired by reviewing medical records for all cats diagnosed with adrenal neoplasms at seven referral institutions between 2002 and 2013. Inclusion criteria required a histopathologic diagnosis of an adrenal neoplasm (ante-mortem or on necropsy). RESULTS: Thirty-three cats met the inclusion criteria for the study. The most common presenting complaints included weakness (n = 12), respiratory signs (n = 4), blindness (n = 4) or gastrointestinal signs (n = 3). Laboratory abnormalities included hypokalemia (n = 18), alkalemia (n = 12), elevated creatine kinase (>3000, n = 5) and azotemia (n = 4). In addition, hypertension was noted in 13 cats. Thirty cats were diagnosed with cortical tumors (17 carcinomas, 13 adenomas) and three cats were diagnosed with pheochromocytomas. Twenty-five cats underwent tests to evaluate the function of the adrenal tumors; 19/25 cats had functional tumors (hyperaldosteronism [n = 16], hypercortisolemia [n = 1], high estradiol [n = 1], and hypersecretion of aldosterone, estradiol and progesterone [n = 1]). Twenty-six cats underwent adrenalectomy, one cat was medically managed and six were euthanized without treatment. Long-term survival postoperatively ranged from 4-540 weeks, with 20 (77%) cats surviving the perioperative period of 2 weeks. The only variable that was found to be negatively associated with survival was female sex. The most common complications noted during the perioperative period were hemorrhage and progressive lethargy and anorexia. CONCLUSIONS AND RELEVANCE: Surgical treatment for feline adrenal tumors (regardless of tumor type) resulted in good long-term survival. Given that pre- and postoperative hypocortisolemia was identified in this study, and, in addition, hypersecretion of more than one adrenal hormone occurred in one cat, adrenal panels prior to surgery may be beneficial as part of the preoperative work-up.

Characterization, treatment, and outcome of bacterial cholecystitis and bactibilia in dogs.

Objective-To characterize historical, clinicopathologic, ultrasonographic, microbiological, surgical, and histopathologic features of bacterial cholecystitis and bactibilia in dogs and evaluate response to treatment and outcomes in these patients. Design-Retrospective case-control study. Animals-40 client-owned dogs (10 with bacterial cholecystitis on histologic analysis or bactibilia on cytologic examination [case dogs] and 30 without bactibilia [controls]) evaluated at a veterinary teaching hospital between 2010 and 2014. Procedures-Signalment, history, clinicopathologic findings, ultrasonographic features, microbiological results, surgical findings, histopathologic changes, treatments, and outcomes of case dogs were derived from medical records and summarized. Demographic and clinicopathologic data and ultrasonographic findings were compared between case and control dogs. Relationships among prior antimicrobial treatment, sediment formation in the gallbladder, presence of immobile biliary sludge, and presence of bactibilia or bacterial cholecystitis were assessed. Results-No finding was pathognomonic for bactibilia or bacterial cholecystitis in dogs. Case dogs were significantly more likely to have immobile biliary sludge and had a greater degree of biliary sediment formation than did control dogs. All case dogs for which gallbladders were examined histologically (6/6) had bacterial cholecystitis. Five of 10 case dogs were Dachshunds. Medical or surgical treatment resulted in good outcomes. Conclusions and Clinical Relevance-Bactibilia and bacterial cholecystitis were important differential diagnoses in dogs with signs referable to biliary tract disease. Dachshunds were overrepresented, which may suggest a breed predisposition. Cytologic evaluation of bile should be considered in the routine assessment of dogs with hepatobiliary disease if immobile biliary sludge is present. (J Am Vet Med Assoc 2015;246:982-989).