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Background: Nonthyroidal illness syndrome (NTIS) can result in thyroid function test alterations that mimic hypothyroidism. The duration of NTIS-induced changes in dogs is not well-described., Objectives: Document alterations in thyroid function tests during NTIS and recovery, and the time necessary for their resolution., Animals: From 103 dogs sampled, 25 euthyroid dogs with acute, resolvable illness having a low serum total thyroxine (TT4) concentration on admission were analyzed., Methods: Prospective observational study. Serum TT4 concentration was measured in 103 dogs within 4 hours of admission. If below the reference interval (RI), subsequent serum samples were obtained every 24 hours from admission until discharge (acute phase) and at 2 weeks and 4 weeks after discharge (recovery phase). Serum samples were submitted for batch measurement of serum TT4, free thyroxine (fT4), total 3,5,3'-triiodothyronine (TT3), and thyroid-stimulating hormone (TSH) concentrations., Results: In the cohort of dogs analyzed, serum TT4, TT3, and fT4 concentrations were below the RI in 100%, 80%, and 16% at admission; 20%, 80%, and 0% at discharge; 4%, 8%, and 0% at 2 weeks; and 0%, 0%, and 0% at 4 weeks, respectively. Serum TSH concentration was within the RI in 100% at admission and discharge, and above the RI in 4% and 12% at 2 weeks and 4 weeks, respectively., Conclusions and Clinical Importance: Naturally occurring NTIS in dogs induces alterations in thyroid function tests during acute illness and recovery. Measurement of serum TT4 concentration 2 to 4 weeks after discharge or serum fT4 concentration by ED during illness is recommended for accurate assessment of thyroid function in acutely ill dogs., (© 2023 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Erroneous thyroid function test results can occur because of drugs that alter thyroid hormone physiology in one or more aspects, including synthesis, secretion, distribution, and metabolism. Research since publication of the last review in the Journal of Veterinary Internal Medicine (JVIM) 20 years ago has evaluated the effects of amiodarone, zonisamide, inhalant anesthetics, clomipramine, trilostane, and toceranib on thyroid function tests in the dog. In addition, recent work on the effects of glucocorticoids, sulfonamides, phenobarbital, and nonsteroidal anti-inflammatory drugs will be reviewed. Awareness of these effects is necessary to avoid misdiagnosis of hypothyroidism and unnecessary treatment., (© 2023 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Background: The pathogenesis of gallbladder (GB) mucoceles in dogs is unknown. It has been proposed that hyperlipidemia could impair GB motility and contribute to GB mucocele formation., Hypothesis/objectives: The objective of this study was to compare GB motility in dogs with hyperlipidemia to control dogs using ultrasonography. We hypothesized that hyperlipidemic dogs will have decreased GB motility compared with controls., Animals: Twenty-six hyperlipidemic and 28 healthy, age-matched control dogs were prospectively enrolled., Methods: Cholesterol and triglyceride concentrations were measured in all dogs. Hyperlipidemia was defined as hypercholesterolemia (>332 mg/dL) and/or hypertriglyceridemia (>143 mg/dL) using a biochemical analyzer. Ultrasound was performed before feeding, and 60 and 120 minutes after ingestion of a high fat diet. Gallbladder volumes (GBV) and ejection fractions (EF) were calculated., Results: Hyperlipidemic dogs had significantly larger GBVs (ml/kg) before feeding and 60 minutes after feeding of 1.2 (0.4-7.5; P = .008) and 0.6 (0.1-7.2; P = .04) compared with controls 0.6 (0.2-2.6) and 0.4 (0.1-1.9), respectively. Severely hyperlipidemic dogs had significantly larger GBV at baseline, 60 minutes, and 120 minutes of 1.7 (0.6-7.5; P = .03), 1.3 (0.4-7.2; P = .02), and 1.3 (0.2-8.2; P = .04), respectively compared with mildly hyperlipidemic dogs. EFs at 60 and 120 minutes between controls, hyperlipidemic, and severely hyperlipidemic were all 0.3 at 60 minutes and 0.5, 0.3, and 0.3 at 120 minutes, respectively which were not statistically different., Conclusions and Clinical Importance: Hyperlipidemia leads to GB distention in dogs which could lead to retention of bile and gallbladder disease., (© 2023 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Background: Hyperthyroid cats might have a predisposition to arterial thrombus formation. The mechanism for thrombogenesis currently is unknown but could be associated with systemic hypercoagulability as seen in hyperthyroid humans., Objective: Our purpose was to evaluate markers of hemostasis in hyperthyroid cats compared to healthy cats, and in hyperthyroid cats before and after radioactive iodine treatment (RIT)., Animals: Twenty-five cats with hyperthyroidism and 13 healthy euthyroid cats >8 years of age., Methods: Prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen concentration, antithrombin (AT), D-dimers, thrombin-antithrombin complexes (TAT), von Willebrand Factor antigen (vWF : Ag), and activity of factors VIII and IX were measured. An echocardiogram was performed in all cats. Hemostatic markers and echocardiogram were evaluated again 6 to 9 months after successful RIT in 7 cats., Results: Hyperthyroid cats had higher fibrinogen concentration (P < .0001), AT activity (P < .0001), and vWF : Ag concentration (P = .01) than healthy control cats with all results decreasing significantly post-RIT. Hyperthyroid cats were not more likely to be in a hypercoaguable state than euthyroid cats (P = .08). Serum T4 concentration was not a predictor of a hypercoagulable state (P = .53)., Conclusions and Clinical Importance: Hyperthyroid cats have evidence of altered hemostasis that does not appear to be solely attributable to cardiac abnormalities, but no evidence of a hypercoagulable state. Findings suggest altered hemostasis resolves after RIT. Hyperthyroid cats could have endothelial dysfunction as indicated by increased vWF : Ag which could potentiate thrombogenesis., (© 2021 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Objectives: Urinary tract infections (UTIs) are reported to be relatively common in hyperthyroid cats, with prevalence rates ranging from 12% to 22%. Factors that are associated with UTIs include age, decreasing body weight and active urine sediments. The purpose of this study was to investigate the prevalence of positive urine cultures (PUCs) in hyperthyroid cats and associated risk factors for PUC., Methods: In total, 197 hyperthyroid cats presenting for radioiodine therapy had urine cultures prospectively performed on cystocentesis samples. Data pertaining to clinical signs, drug history, age, weight, blood urea nitrogen, creatinine, serum thyroxine and urinalysis were also evaluated., Results: The prevalence of PUCs in this population of hyperthyroid cats was 5.1% and all cats were subclinical. Microscopic bacteriuria was significantly associated with a PUC (60%) compared with a negative urine culture (1.6%) status. Age, weight, urine specific gravity <1.020, urine pH, hematuria, pyuria, thyroxine concentration, breed and sex were not associated with PUC status., Conclusions and Relevance: The prevalence of PUCs in this population of cats was lower than previous reports of cats with hyperthyroidism. Cats with a PUC were subclinical at the time of culture, regardless of urine sediment abnormalities. Further studies are necessary to determine the clinical significance of subclinical bacteriuria in hyperthyroid cats.

Objectives: Cats with hyperthyroidism have been reported to develop thromboembolism, with and without echocardiographic abnormalities consistent with hyperthyroidism. The objective of this study was to compare platelet function in cats with hyperthyroidism with euthyroid age-matched cats. We hypothesized that cats with hyperthyroidism have shortened collagen and adenosine diphosphate (C-ADP) closure times as measured with the platelet function analyzer (PFA-100) in comparison with healthy, age-matched controls., Methods: Sixteen hyperthyroid and nine euthyroid healthy cats >7 years of age were recruited from the hospital population. Platelet function, measured using the C-ADP closure times by the PFA-100, and platelet count were measured in healthy euthyroid cats and cats with hyperthyroidism., Results: Mean ± SD closure times were not significantly different between control (66.3 ± 9.6 s) and hyperthyroid cats (65.9 ± 11.5 s; P  = 0.75). The mean ± SD closure times of hyperthyroid cats that either were untreated or received methimazole for ⩽3 weeks (n = 6; mean 68.5 ± 15.4 s) was not different than that of cats treated for >3 weeks (n = 10; mean 64.3 ± 8.9 s; P  = 0.57). The mean automated platelet count was higher in the hyperthyroid group than in the control group ( P  = 0.023)., Conclusions and Relevance: Platelet function, as measured by closure time under high shear conditions using C-ADP as an agonist, was not affected by hyperthyroidism in this group of cats. Further research is needed to determine if a hypercoagulable state exists in hyperthyroid cats and the potential roles platelets and von Willebrand factor may have.

Background: Pancreatitis is a common cause of extrahepatic bile duct obstruction (EHBDO) in dogs. Information describing the clinical course of dogs with pancreatitis associated bile duct obstruction (PABDO) is limited., Objectives: To describe the clinical course of PABDO in dogs and determine if presumed markers of disease severity are predictors of survival., Animals: Forty-six client-owned dogs with PABDO., Methods: A retrospective review of medical records from dogs diagnosed with PABDO was performed. Data, including clinical signs and biochemical changes, were collected 6 times throughout the course of disease. Outcome was defined as either survival (discharge from the hospital) or death., Results: Thirty-three (79%) out of 42 dogs with PABDO survived. Thirty-one (94%) of the 33 dogs that survived received medical management alone. Time from onset of clinical signs to initial documented increase in serum bilirubin concentration, peak bilirubin elevation, and initial decline in serum bilirubin concentration were 7 (median), 8, and 15 days, respectively. The median number of days from onset of clinical signs to outcome date was 13. Clinical signs of fever, vomiting, and anorexia were decreased in frequency from the onset of clinical signs to the time of peak bilirubin. Median bile duct dilatation at the time of ultrasonographic diagnosis of PABDO and peak bilirubin were not different between survivors (7.6 mm, 11.7 mg/dL) and nonsurvivors (6 mm, 10.6 mg/dL, P = .12, P = .8)., Conclusions: Dogs with PABDO often have a prolonged course of illness and improve clinically despite biochemical evidence of progression of EHBDO., (© 2020 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Objectives: The purpose of this study was to evaluate symmetric dimethylarginine (SDMA) in hyperthyroid cats before and after treatment with radioactive iodine and to determine how pretreatment SDMA relates to the development of post-treatment azotemia., Methods: Eighty-four non-azotemic hyperthyroid cats had serum SDMA and creatinine evaluated before and 1, 3 and 6 months after treatment with radioiodine therapy., Results: Baseline SDMA was increased in 7% (n = 6/84) of cats, whereas SDMA was increased in 19% (n = 15/81), 20% (n = 16/80) and 32% (n = 26/81) at 1 month, 3 months and 6 months after treatment, respectively. Creatinine was not elevated in any of the cats at baseline because of the study design, and was elevated in 6% (n = 5/81), 15% (n = 12/80) and 15% (n = 12/81) of cats at 1, 3 and 6 months after treatment, respectively. SDMA (median 11 μg/dl, range 1-22 μg/dl) was significantly higher at 3 (12 μg/dl, range 6-45 μg/dl; P = 0.005) and 6 months (11 μg/dl, 6-25 μg/dl; P <0.001) compared with baseline (11 μg /dl, range 1-21 μg/dl). The median baseline SDMA was significantly higher in the azotemic group (13 μg/dl, range 11-22 μg/dl) compared with the non-azotemic group (10 μg/dl, range 1-21 μg/dl, P = 0.002). The sensitivity of SDMA for detecting azotemia after treatment was 15.4%, with a specificity of 94.4%. Baseline serum SDMA concentration had a moderately positive association with baseline creatinine concentration ( P <0.001, r = 0.437). At 6 months, there was a strong positive correlation between SDMA and creatinine concentrations ( P <0.001, r = 0.721). There was no significant correlation with SDMA and thyroxine at baseline ( P = 0.772, r = -0.034) or 6 months ( P = 0.492, r = -0.078)., Conclusions and Relevance: SDMA increases in cats treated for hyperthyroidism with radioactive iodine and likely reflects associated changes in glomerular filtration rate. An increased SDMA concentration above the reference interval prior to treatment has a high specificity but poor sensitivity for the prediction of post-treatment azotemia.

Background: Radioiodine is the treatment of choice for hyperthyroidism in cats. The ideal method of dose determination of radioiodine remains controversial., Objective: To compare a method of radioiodine dose determination that utilized thyroid scintigraphy with a standard fixed dose for treatment of hyperthyroidism., Animals: Fifty-seven and 23 client-owned hyperthyroid cats in the variable and fixed dose groups, respectively., Methods: Cats with a percent dose uptake using 99m Tc-pertechnetate uptake on thyroid scintigraphy <5%, 5%-10%, and >10% were to receive 3, 3.5, or 4.5 millicuries (mCi) of radioiodine, respectively, administered SC. Radioiodine dose was adjusted according to thyroid gland size as determined by the thyroid:salivary size ratio and categorized as <5:1, 5-10:1, and >10:1. If the thyroid size fell into a higher dosing category than the percent dose uptake, the dose was increased accordingly. Cats in the fixed dose group received 4.5 mCi. Six months after treatment, cats were determined to be euthyroid, hypothyroid, or hyperthyroid based on serum thyroxine and thyroid stimulating hormone concentrations., Results: No difference in outcome was found between the variable and fixed dose treatment groups. Euthyroidism, hypothyroidism, and persistent hyperthyroidism developed in 61, 30, and 9% of cats in the fixed dose group compared to 58, 26, and 16%, respectively, in the variable dose group., Conclusions: A variable dosing method of radioiodine based on percent dose uptake primarily and thyroid gland size secondarily did not improve outcome compared to a standard fixed dose method., (Copyright © 2018 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.)

Scottish terriers (ST) frequently have increased serum alkaline phosphatase (ALP) of the steroid isoform. Many of these also have high serum concentrations of adrenal sex steroids. The study's objective was to determine the cause of increased sex steroids in ST with increased ALP. Adrenal gland suppression and stimulation were compared by low dose dexamethasone (LDDS), human chorionic gonadotropin (HCG) and adrenocorticotropic hormone (ACTH) response tests. Resting plasma pituitary hormones were measured. Steroidogenesis-related mRNA expression was evaluated in six ST with increased ALP, eight dogs of other breeds with pituitary-dependent hyperadrenocorticism (HAC), and seven normal dogs. The genome-wide association of single nucleotide polymorphisms (SNP) with ALP activity was evaluated in 168 ST. ALP (reference interval 8-70 U/L) was high in all ST (1,054 U/L) and HAC (985 U/L) dogs. All HAC dogs and 2/8 ST had increased cortisol post-ACTH administration. All ST and 2/7 Normal dogs had increased sex steroids post-ACTH. ST and Normal dogs had similar post-challenge adrenal steroid profiles following LDDS and HCG. Surprisingly, mRNA of hydroxysteroid 17-beta dehydrogenase 2 (HSD17B2) was lower in ST and Normal dogs than HAC. HSD17B2 facilities metabolism of sex steroids. A SNP region was identified on chromosome 5 in proximity to HSD17B2 that correlated with increased serum ALP. ST in this study with increased ALP had a normal pituitary-adrenal axis in relationship to glucocorticoids and luteinizing hormone. We speculate the identified SNP and HSD17B2 gene may have a role in the pathogenesis of elevated sex steroids and ALP in ST.

CASE DESCRIPTION A 7-year-old castrated male Havanese was evaluated at a veterinary teaching hospital because of a 12-week history of hyperactivity, aggression, and progressive weight loss despite a healthy appetite. CLINICAL FINDINGS Tachycardia was the only remarkable finding during physical examination. Serum 3,5,3'-triiodothyronine (T3) and free T3 concentrations were markedly increased, and thyroxine (T4), free T4, and thyroid-stimulating hormone concentrations were at or decreased from the respective reference ranges. Thyroid scintigraphy revealed suppressed uptake of sodium pertechnetate Tc 99m by the thyroid gland but no ectopic thyroid tissue, which was indicative of thyrotoxicosis induced by an exogenous source of T3. TREATMENT AND OUTCOME The dog was hospitalized for 24 hours, and its diet was changed, after which the clinical signs rapidly resolved and serum T3 and free T3 concentrations returned to within the respective reference ranges. This raised suspicion of an exogenous source of T3 in the dog's home environment. Analysis of the commercial beef-based canned food the dog was being fed revealed a high concentration of T3 (1.39 μg/g) and an iodine (82.44 μg/g) concentration that exceeded industry recommendations. No other source of T3 was identified in the dog's environment. CLINICAL RELEVANCE To our knowledge, this is the first report of clinical thyrotoxicosis in a dog induced by exogenous T3, although the source of exogenous T3 was not identified. This case highlights the importance of measuring serum T3 and thyroid-stimulating hormone concentrations in addition to T4 and free T4 concentrations when there is incongruity between clinical findings and thyroid function test results.

Background: Chronic supplementation can suppress the hypothalamic-pituitary-thyroid axis (HPTA) and make it difficult to assess thyroid function after withdrawal of levothyroxine., Objectives: To determine whether the HPTA is suppressed after levothyroxine administration in euthyroid dogs and the time required for resolution of any suppression., Animals: Twenty-eight healthy euthyroid dogs., Methods: A prospective, randomized study administering levothyroxine to euthyroid dogs for 8 weeks (group 1) or 16 weeks (group 2). Serum concentrations of total thyroxine (T 4 ), free thyroxine (fT 4 ) by equilibrium dialysis, thyroid stimulating hormone; thyrotropin (TSH), and 3,5,3'-triiodothyronine (T 3 ) were measured every 4 weeks during supplementation and for 16 weeks after levothyroxine was discontinued., Results: Mean serum concentrations of T 4 and fT 4 were significantly higher (P < .0001) and TSH was lower (P < .0001) in all dogs during levothyroxine administration compared to baseline. Mean serum concentrations of T 4 , fT 4, and TSH in both groups, beginning 1 week after levothyroxine was discontinued, were significantly different (P < .01) compared to values during levothyroxine administration but not compared to baseline values (P > .3)., Conclusions and Clinical Importance: Assessing thyroid function tests 1 week after cessation of levothyroxine at 26 μg/kg once a day for up to 16 weeks will provide an accurate assessment of thyroid function in healthy euthyroid dogs., (Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.)

Background: Biliary sludge is associated with gallbladder (GB) dysmotility and mucus hypersecretion suggesting a link between biliary sludge and the formation of GB mucoceles (GBM). If biliary sludge progresses to GBM, treatment to reduce the production and progression of sludge is warranted., Hypothesis/objectives: The objective of this study was to determine the course of biliary sludge in dogs., Animals: Seventy-seven healthy, client-owned dogs ≥4 years of age screened for biliary sludge; 45 affected dogs identified., Methods: Prospective, observational design. Serial ultrasound examinations were evaluated at 3, 6, 9, and 12 months to monitor degree of sludge based on proportion of GB filled with sludge (mild [0.01-24.4%], moderate [24.5-49.4%], moderate to severe [49.5-74.4%], severe [74.5-100%]), gravity dependency of sludge, and GB dimensions., Results: After 1 year of follow-up, the degree of sludge was mild (34%), moderate (47%), moderate to severe (13%), severe (3%), or absent (3%). There was no significant difference in median degree of sludge over 1 year (P = .36). There were no significant changes in the gravity dependency of sludge over 1 year. A subset of dogs, 24%, with initial gravity-dependent sludge developed a combination of nondependent and dependent sludge. Dogs had resolved (2%), decreased (19%), static (40%), increased (29%), or recurrent (10%) sludge at the conclusion of the study., Conclusions and Clinical Importance: Biliary sludge was prevalent, affected dogs remained asymptomatic, and it rarely resolves in healthy dogs over a period of 1 year. Some dogs developed nongravity-dependent sludge within 1 year, which might indicate changes in consistency of sludge., (Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.)

Objective: To determine the effect of experimentally induced hypothyroidism on isoflurane (ISO) minimum alveolar concentration (MAC) in dogs., Study Design: Prospective experimental study., Animals: Eighteen adult female mongrel dogs, age 2-4 years and weighing 8.2-13.1 kg., Methods: Hypothyroidism was induced in nine dogs by the intravenous administration of 1 mCi kg(-1) of (131) Iodine. The remaining nine dogs served as controls. Dogs were studied 9-12 months after the induction of hypothyroidism. Anesthesia was induced with ISO in oxygen via a mask. The trachea was intubated, and anesthesia was maintained using ISO in oxygen using a semi-closed rebreathing circle system. The dogs were mechanically ventilated to maintain an end-tidal carbon dioxide concentration between 35 and 45 mmHg. End-tidal ISO concentrations were measured with an infrared gas analyzer. The MAC was determined in duplicate using a tail clamp technique. The mean values for the groups were compared using a two sample t-test., Results: The mean ± SD MAC of isoflurane in the hypothyroid and euthyroid dogs was 0.98 ± 0.31% and 1.11 ± 0.26%, respectively. The mean MAC of isoflurane in hypothyroid dogs was not significantly different from the mean MAC of isoflurane in the control dogs (p = 0.3553)., Conclusion and Clinical Relevance: The MAC of ISO in dogs was not significantly affected by experimentally induced hypothyroidism. The dose of ISO in dogs with hypothyroidism does not need to be altered., (© 2014 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.)

Background: Biopsy of the liver evaluates a small portion of tissue, with inferences made to the entire organ. The method and number of biopsies obtained are tempered by consideration of the risks and benefits. Recommendations often include biopsy of more than one liver lobe, although the consistency of histopathology among lobes in dogs is unknown., Hypothesis/objectives: To describe the distribution of histopathologic abnormalities between liver lobes. We hypothesized that discordant results would be evenly distributed among all liver lobes., Animals: Seventy dogs undergoing necropsy., Methods: Prospective study. Liver samples were obtained from all lobes. A primary diagnosis was assigned to each liver sample based on the predominant histopathologic abnormality., Results: In this population of dogs, biopsy of at least 2 liver lobes identified the predominant histologic abnormality in 98.6% of the cases. Ten (14%) of the dogs had ≤ 3 lobes in agreement and could not be assigned a predominant diagnosis. The same diagnosis was present in 6/6 lobes in 39 (56.5%) dogs, 5/6 lobes in 10 (14.5%) dogs, 4/6 lobes in 10 (14.5%) dogs, 3/6 lobes in 7 (10.1%) dogs, and 2/6 in 3 (4.3%) dogs. The number of discordant results did not differ between the liver lobes., Conclusion and Clinical Importance: The likelihood of obtaining a sample that is reflective of the predominant histologic abnormality in the liver is increased when multiple liver lobes are biopsied., (Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of American College of Veterinary Internal Medicine.)

Background: The liver sampling technique in dogs that consistently provides samples adequate for accurate histopathologic interpretation is not known., Hypothesis/objectives: To compare histopathologic results of liver samples obtained by punch, cup, and 14 gauge needle to large wedge samples collected at necropsy., Animals: Seventy dogs undergoing necropsy., Methods: Prospective study. Liver specimens were obtained from the left lateral liver lobe with an 8 mm punch, a 5 mm cup, and a 14 gauge needle. After sample acquisition, two larger tissue samples were collected near the center of the left lateral lobe to be used as a histologic standard for comparison. Histopathologic features and numbers of portal triads in each sample were recorded., Results: The mean number of portal triads obtained by each sampling method were 2.9 in needle samples, 3.4 in cup samples, 12 in punch samples, and 30.7 in the necropsy samples. The diagnoses in 66% of needle samples, 60% of cup samples, and 69% of punch samples were in agreement with the necropsy samples, and these proportions were not significantly different from each other. The corresponding kappa coefficients were 0.59 for needle biopsies, 0.52 for cup biopsies, and 0.62 for punch biopsies., Conclusion and Clinical Importance: The histopathologic interpretation of a liver sample in the dog is unlikely to vary if the liver biopsy specimen contains at least 3-12 portal triads. However, in comparison large necropsy samples, the accuracy of all tested methods was relatively low., (Copyright © 2014 by the American College of Veterinary Internal Medicine.)

Transplacental infection with Blastomyces dermatitidis is rare in humans and unknown in the dog. A Doberman pinscher bitch was diagnosed with blastomycosis 25 days after whelping. Clinical signs were noted after whelping and were progressive. All 9 pups were free of clinical signs and had negative urine Blastomyces antigen tests at 6 weeks of age and remained free of signs of illness through 11 months of age. The bitch responded to treatment with itraconazole.

Background: The prevalence and progression of vascular complications of spontaneous diabetes mellitus (DM) in dogs have not been described., Objectives: To investigate the effects of duration of disease, as estimated by time since DM diagnosis, and glycemic control on prevalence of systemic hypertension, proteinuria, and diabetic retinopathy in dogs with spontaneous DM., Animals: Seventeen client-owned dogs with spontaneous DM., Methods: Prospective, longitudinal observational study. Dogs with DM of less than 1 year's duration were recruited and evaluated once every 6 months for 24 months. Recorded measures included indirect BP, urine albumin, protein and creatinine concentrations, serial blood glucose and serum fructosamine concentrations, ophthalmic examination, and a standardized behavioral questionnaire., Results: Eleven dogs completed the 2-year follow-up period, during which the highest recorded prevalence of systolic and diastolic hypertension was 55 and 64%, respectively. Prevalence of microalbuminuria and elevated urine protein:creatinine ratio (UPC) ranged up to 73 and 55%, respectively. Prevalence of retinopathy ranged up to 20%. No significant effect of time since DM diagnosis or glycemic control was detected for any of the measures examined. Additionally, no significant associations between BP, urine albumin concentration, UPC and retinopathy were detected., Conclusions and Clinical Relevance: With the exception of proteinuria, which was substantial in some cases, clinically deleterious diabetic vascular complications were not identified in dogs in this study., (Copyright © 2014 by the American College of Veterinary Internal Medicine.)

Background: Hyperthyroidism has substantial effects on the circulatory system. The cardiac biomarkers NT-proBNP and troponin I (cTNI) have proven useful in identifying cats with myocardial disease but have not been extensively investigated in hyperthyroidism., Hypothesis: Plasma NT-proBNP and cTNI concentrations are higher in cats with primary myocardial disease than in cats with hyperthyroidism and higher in cats with hyperthyroidism than in healthy control cats., Animals: Twenty-three hyperthyroid cats, 17 cats with subclinical hypertrophic cardiomyopathy (HCM), and 19 euthyroid, normotensive healthy cats ≥8 years of age. Fourteen of the hyperthyroid cats were re-evaluated 3 months after administration of radioiodine ((131)I)., Methods: Complete history, physical examination, complete blood count, serum biochemistries, urinalysis, blood pressure measurement, serum T4 concentration, plasma concentrations of NT-proBNP and cTNI, and echocardiogram were obtained prospectively from each cat., Results: Hyperthyroid cats and cats with HCM had plasma NT-proBNP and cTNI concentrations that were significantly higher than those of healthy cats, but there was no significant difference between hyperthyroid cats and cats with HCM with respect to the concentration of either biomarker. In hyperthyroid cats that were re-evaluated 3 months after (131) I treatment, plasma NT-proBNP and cTNI concentrations as well as ventricular wall thickness had decreased significantly., Conclusions and Clinical Importance: Although there may be a role for NT-proBNP in monitoring the cardiac response to treatment of hyperthyroidism, neither NT-proBNP nor cTNI distinguish hypertrophy associated with hyperthyroidism from primary HCM. Therefore, the thyroid status of older cats should be ascertained before interpreting NT-proBNP and cTNI concentrations., (Copyright © 2013 by the American College of Veterinary Internal Medicine.)

Thyroid hormones have many effects on cardiovascular function, and deficiency or excess of thyroid hormones can result in cardiac dysfunction. Abnormalities of the cardiovascular system are often identified during examination of hyperthyroid and hypothyroid patients. This article addresses the effects of thyroid hormones on the cardiovascular system and the clinical relevance of the cardiovascular response to thyroid dysfunction. In addition, treatment recommendations are presented.

Background: Pancreatitis is a common disease in cats that is difficult to diagnose., Hypothesis/objectives: To determine the sensitivity and specificity of ultrasonographic changes of the pancreas with serum feline pancreatic lipase immunoreactivity (fPLI) as the standard for diagnosis of pancreatitis., Animals: 35 cats with clinical signs consistent with pancreatitis with an abdominal ultrasound examination and serum fPLI concentration measured within 3 days of the ultrasound., Methods: Retrospective study: Pancreatic thickness, pancreatic margination, pancreatic echogenicity, and peripancreatic fat echogenicity were evaluated. Sensitivity and specificity were calculated with an elevated serum fPLI concentration indicative of pancreatitis as the standard for diagnosis., Results: Serum fPLI was elevated and diagnostic for pancreatitis in 19 of 35 cats. The single ultrasound characteristic with the highest sensitivity was hyperechoic peripancreatic fat at 68% (95% confidence interval = 44-87%), indicating a moderate probability that cats with pancreatitis will have this abnormality on ultrasonographic examination. Specificity was >90% for each of increased pancreatic thickness, abnormal pancreatic margin, and hyperechoic peripancreatic fat. The sensitivity and specificity of ultrasound were 84% (95% confidence interval = 60-97%) and 75% (95% confidence interval = 48-93%), respectively, in cats with elevated serum fPLI indicative of pancreatitis., Conclusions and Clinical Importance: The presence of a thick left limb of the pancreas, severely irregular pancreatic margins, and hyperechoic peripancreatic fat in cats with appropriate clinical signs and elevated serum fPLI are highly supportive of pancreatitis., (Copyright © 2013 by the American College of Veterinary Internal Medicine.)

Background: Ultrasound examination is commonly used in the diagnostic evaluation of liver disease in dogs., Hypothesis/objectives: To determine if hepatic sonographic features were predictive of findings on liver histopathology. We hypothesized that there would be a relationship between sonographic features and the category of liver disease based on histologic assessment., Animals: One hundred and thirty-eight dogs in which the liver was evaluated by both abdominal ultrasound examination and histopathologic examination. Twenty-five dogs were included in each of the following categories based on histopathology: normal, degenerative, vascular, inflammatory, and neoplasia. Thirteen dogs had nodular regeneration., Methods: Retrospective study. Medical records of dogs from 2005 to 2010 were searched for cases in which the liver was evaluated by abdominal ultrasound examination as well as by histopathology. After independent evaluation of ultrasound images, the recorded sonographic features were analyzed to identify abnormalities associated with each histopathologic diagnosis or degree of fibrosis., Results: Sixty-four percent of sonographically unremarkable livers had histologic abnormalities. Both microhepatia and the identification of abnormal vasculature were significantly associated with a histopathologic diagnosis of vascular disease. Hepatic masses were significantly associated with a diagnosis of neoplasia. Dilated common bile duct and thickened gall bladder wall were significantly associated with hepatitis. There were no sonographic findings consistently present with hepatic fibrosis., Conclusion and Clinical Importance: Although some ultrasonographic findings, including masses, microhepatia, anomalous veins, and biliary changes, are associated with specific histopathologic abnormalities, sonographic findings are inconsistently detected in many disorders. Overall, hepatic ultrasonographic abnormalities have substantial limitations in predicting the underlying disease., (Copyright © 2013 by the American College of Veterinary Internal Medicine.)

We describe an opportunistic, disseminated infection in a German shepherd dog associated with two fungal organisms not previously reported to cause disease. Lecythophora canina, a new species here described, was isolated from an osteolytic bone lesion. A fine needle aspirate of the lesion demonstrated septate hyphae. Plectospharella cucumerina (anamorph Plectosporium tabacinum) was isolated from a urine sample. Clinical manifestations were blindness, altered mentation, and osteomyelitis. Treatment with itraconazole and terbinafine for greater than one year resulted in stable clinical disease.

Background: Chronic diarrhea is common in dogs and has many causes. Ultrasonographic descriptions of many gastrointestinal diseases have been published, but the diagnostic utility of ultrasonography in dogs with chronic diarrhea has not been investigated., Hypothesis: Diagnostic utility of abdominal ultrasound will be highest in dogs with GI neoplasia and lowest in those with inflammatory disorders., Animals: 87 pet dogs with chronic diarrhea., Methods: Prospective study in which medical records were reviewed and contribution of abdominal ultrasound toward making diagnosis was scored., Results: In 57/87 (66%) of dogs, the same diagnosis would have been reached without ultrasonography. In 13/87 (15%) of dogs, the ultrasound examination was vital or beneficial to making the diagnosis. Univariable analysis identified that increased diagnostic utility was associated with weight loss (P = .0086), palpation of an abdominal or rectal mass (P = .0031), diseases that commonly have mass lesions visible on ultrasound examination (P < .0001), and a final diagnosis of GI neoplasia. Multivariable regression indicated that utility of abdominal ultrasonography would be 30 times more likely to be high in dogs in which an abdominal or rectal mass was palpated (odds ratio 30.5, 95% CI 5.5-169.6) (P < .0001) versus dogs without a palpable mass. In 15/87 (17%) of dogs, additional benefits of ultrasonography to case management, independent of the contribution to the diagnosis of diarrhea, were identified., Conclusions and Clinical Importance: Overall, the diagnostic utility of abdominal ultrasonography was low in dogs with chronic diarrhea. Identification of factors associated with high diagnostic utility is an indication to perform abdominal ultrasonography in dogs with chronic diarrhea., (Copyright © 2012 by the American College of Veterinary Internal Medicine.)

Objective: To determine the effects of oral prednisone administration with or without ultralow-dose acetylsalicylic acid on coagulation parameters in healthy dogs and to assess intraindividual variation in thromboelastography results., Animals: 14 healthy research dogs and 10 healthy client-owned dogs., Procedures: In a randomized controlled trial, research dogs underwent thromboelastography twice (3 days apart), and intraindividual variation in test results was calculated. Dogs were given prednisone (2 mg/kg/d, PO) plus acetylsalicylic acid (0.5 mg/kg/d, PO) or prednisone (2 mg/kg/d, PO) plus a placebo for 14 days, after which thromboelastography and other tests were repeated. Differences from preadministration (baseline) test results between and within groups were compared. In a separate trial, client-owned dogs also underwent thromboelastography twice 2 days apart to assess intraindividual variation in untreated dogs., Results: Intraindividual variation in thromboelastography results for research dogs was ≤ 10% for maximum amplitude (MA) and α angle. In the research dogs, MA and fibrinogen values significantly increased from baseline, whereas percentage lysis 30 minutes after attainment of the MA as well as antithrombin activity significantly decreased within each group. In the dogs that received prednisone plus a placebo, percentage lysis 60 minutes after attainment of the MA was significantly lower than at baseline. For all parameters for research dogs, there was no difference between groups for change from baseline. Intraindividual variation in findings for client-owned dogs was similar to the variation for research dogs., Conclusions and Clinical Relevance: Prednisone administration resulted in hypercoagulability in healthy dogs as indicated by an increase in MA and plasma fibrinogen concentration and a decrease in antithrombin activity. Concurrent ultralow-dose acetylsalicylic acid use had no effect on measured thromboelastography values. The high intraindividual variation in some thromboelastography parameters may preclude routine use of this technique in clinical practice.

Background: Increases of adrenal hormone concentrations other than cortisol have been reported in dogs with hyperadrenocorticism (HAC)., Hypothesis/objectives: Measuring noncortisol adrenal hormone concentrations will help identify HAC in dogs. The objective was to determine plasma cortisol, androstenedione, estradiol, progesterone, testosterone, and 17-hydroxyprogesterone concentrations during ACTH stimulation testing of dogs with clinical signs of HAC to ascertain their utility in diagnosis of the disease., Animals: Ninety dogs with clinical findings consistent with HAC had ACTH stimulation tests performed. Results from 29 dogs were excluded from analysis because diagnoses were inconclusive for a variety of reasons. Results from 32 dogs with HAC and 29 dogs with disease other than HAC were analyzed., Methods: Prospective observational study. Concentrations of adrenocortical hormones were determined before and 1 hour after injecting 5 μg/kg ACTH IM. Diagnoses were determined by response to therapy, histopathology or both., Results: Post-ACTH cortisol (P < .001), progesterone (P = .001), and 17-hydroxyprogesterone (P < .001) concentrations were associated with a diagnosis of HAC. Sensitivity and specificity, respectively, for diagnosing HAC for post-ACTH cortisol were 84 and 59%, progesterone 88 and 55%, and 17-hydroxyprogesterone 91 and 59%, and for post-ACTH cortisol, progesterone and 17-hydroxyprogesterone combined were 88 and 55%. Of 5 dogs with HAC and normal post-ACTH cortisol concentrations, 5 had increased progesterone and 4 had increased 17-hydroxyprogesterone., Conclusions and Clinical Importance: Serum progesterone and 17-hydroxyprogesterone concentrations were useful to diagnose HAC in this study, but were not more sensitive or specific than cortisol concentration., (Copyright © 2012 by the American College of Veterinary Internal Medicine.)

Objective: To determine the effects of hypothyroidism on insulin sensitivity, glucose tolerance, and concentrations of hormones counter-regulatory to insulin in dogs., Animals: 8 anestrous mixed-breed bitches with experimentally induced hypothyroidism and 8 euthyroid control dogs., Procedures: The insulin-modified frequently sampled IV glucose tolerance test and minimal model analysis were used to determine basal plasma insulin and glucose concentrations, acute insulin response to glucose, insulin sensitivity, glucose effectiveness, and disposition index. Growth hormone response was assessed by stimulation and suppression tests. Additionally, basal serum growth hormone (GH) and insulin-like growth factor-1 (IGF-1) concentrations and urine cortisol-to-creatinine concentration ratios were measured and dual energy x-ray absorptiometry was performed to evaluate body composition., Results: Insulin sensitivity was lower in the hypothyroid group than in the euthyroid group, whereas acute insulin response to glucose was higher. Glucose effectiveness and disposition index were not different between groups. Basal serum GH and IGF-1 concentrations as well as abdominal fat content were high in hypothyroid dogs, but urine cortisol-to-creatinine concentration ratios were unchanged., Conclusions and Clinical Relevance: Hypothyroidism appeared to negatively affect glucose homeostasis by inducing insulin resistance, but overall glucose tolerance was maintained by increased insulin secretion in hypothyroid dogs. Possible factors affecting insulin sensitivity are high serum GH and IGF-1 concentrations and an increase in abdominal fat. In dogs with diseases involving impaired insulin secretion such as diabetes mellitus, concurrent hypothyroidism can have important clinical implications.

Background: Hypothyroidism has detrimental effects on reproduction in females of many species. Studies of hypothyroidism in bitches are limited and results conflicting., Hypothesis: Hypothyroidism interferes with reproductive function and health of offspring in bitches., Animals: A total of 9 healthy mixed-breed bitches (control) and 9 mixed breed bitches with hypothyroidism induced by radioactive iodine administration., Methods: Dogs in both groups were bred 20.9 ± 4.0 and 56 ± 7.6 weeks after radioiodine administration in the hypothyroid group and again after levothyroxine was administered for 37 ± 14 weeks to hypothyroid dogs. Measures of the estrus cycle, fertility, gestation, whelping, and pup health were evaluated at each breeding. Comparisons were made between hypothyroid and control dogs as well as within groups between times., Results: Pregnancy was documented in all dogs in both groups at the 1st breeding, 4/8 and 6/6 untreated hypothyroid and control dogs, respectively, at the 2nd breeding, and 6/6 and 5/6 treated hypothyroid and control dogs, respectively, at the 3rd breeding. Periparturient mortality was higher and birth weight was lower in pups born to untreated hypothyroid dogs compared with control dogs or treated hypothyroid dogs. There was no difference in interestrus interval, gestation duration, breeding behavior, interval between birth of pups, or serum progesterone concentrations at any breeding between or within groups. Resolution of hypothyroidism reversed the detrimental effects of thyroid hormone deficiency on reproduction., Conclusions and Clinical Importance: Hypothyroidism causes reversible periparturient mortality and low birth weight in offspring. Further investigation is necessary to determine if fertility is affected., (Copyright © 2012 by the American College of Veterinary Internal Medicine.)

Iopanoic acid is an iodine containing oral cholecystographic agent that has been used to treat hyperthyroidism in humans and has recently been evaluated in an experimental model of feline hyperthyroidism. The aim of this study was to evaluate the efficacy of iopanoic acid in cats with spontaneous hyperthyroidism. Eleven cats were included in the study. Eight were treated initially with 50mg orally q 12h and three were treated with 100mg orally q 12h. Prior to treatment (baseline) and at 2, 4, and 12 weeks of treatment, owner questionnaires, physical exams, complete blood count, biochemistry analyses, and T(3) and T(4) concentrations were evaluated. The mean serum T(3) concentration decreased with treatment at all time periods compared to baseline. Mean T(4) concentrations were increased at weeks 4 and 12 compared to baseline. Five cats had a partial response during the initial 4 weeks of therapy, but the effects were transient and no significant improvements in clinical signs or physical exam findings were noted at any time period. Results suggest that iopanoic acid may be beneficial for acute management of thyrotoxicosis in some cats, but is not suitable for long-term management., (Published by Elsevier Ltd on behalf of ISFM and AAFP.)

Background: Central nervous system (CNS) manifestations of hypothyroidism have been associated with cerebrovascular complications. Reports of cerebrospinal fluid (CSF) abnormalities are rare in hypothyroid dogs., Objective: The aim of this study was to determine if chronic hypothyroidism causes blood-brain-barrier (BBB) abnormalities that are detectable using indirect CSF biomarkers., Methods: The study included 18 normal, euthyroid, female mixed-breed dogs. Hypothyroidism was induced by (131) iodine administration in 9 dogs; 9 served as untreated controls. Evaluations included physical and neurologic examination, complete CSF analysis, serum and CSF protein electrophoresis, measurement of plasma vascular endothelial growth factor (VEGF) and serum S-100B concentrations, and calculation of CSF albumin quota (AQ) and were conducted at baseline and 6, 12, and 18 months after induction of hypothyroidism. Data were analyzed using repeated measures ANOVA., Results: At baseline, differences between groups were not detected for any variable. Throughout the study, controls dogs remained free of neurologic disease and had test variables that remained within reference intervals. Two hypothyroid dogs developed CNS signs during the study, and evidence of cerebrovascular disease was found at necropsy. At 12 and 18 months, the CSF total protein, VEGF, S-100B, and fractional albumin concentrations, and AQ were significantly higher (P<.04) in hypothyroid dogs than controls. Among test variables assayed in serum or plasma, the only significant difference was a higher S-100B concentration in hypothyroid dogs (P=.003) at 18 months., Conclusions: BBB integrity is disrupted in chronic hypothyroidism. Significant increases in CSF concentrations of VEGF and S100-B in hypothyroid dogs indicate dysfunction in both endothelial and glial elements of the BBB., (©2010 American Society for Veterinary Clinical Pathology.)

Background: Urinary catecholamines and metanephrines have been proposed as a diagnostic tool for identifying canine pheochromocytomas, but the effects of critical illness on urine concentrations of catecholamines and metanephrines currently are unknown., Objectives: To examine the effects of illness on urine concentrations of catecholamines and metanephrines in dogs., Animals: Twenty-five critically ill dogs and 25 healthy age- and sex-matched control dogs., Methods: Prospective observational study. Urine was collected from healthy and critically ill dogs, and urine concentrations of epinephrine, norepinephrine, metanephrine, and normetanephrine were measured by high-performance liquid chromatography with electrochemical detection. Urinary catecholamine and metanephrine:creatinine ratios were calculated and compared between groups., Results: Urinary epinephrine, norepinephrine, metanephrine, and normetanephrine:creatinine ratios were higher in critically ill dogs when compared with a healthy control population (P=.0009, P<0.0001, P<0.0001, and P<0.0001, respectively)., Conclusions and Clinical Importance: Illness has a significant impact on urinary catecholamines and their metabolites in dogs. Further investigation of catecholamine and metanephrine concentrations in dogs with pheochromocytomas is warranted to fully evaluate this test as a diagnostic tool; however, the findings of this study suggest that the results may be difficult to interpret in dogs with concurrent illness., (Copyright © 2010 by the American College of Veterinary Internal Medicine.)

Objective: To determine causes of hyperphosphatasemia (high serum alkaline phosphatase [ALP] activity) in apparently healthy Scottish Terriers., Design: Prospective case-controlled study., Animals: 34 apparently healthy adult Scottish Terriers (17 with and 17 without hyperphosphatasemia)., Procedures: Serum activities for 3 isoforms (bone, liver, and corticosteroid) of ALP were measured. Concentrations of cortisol, progesterone, 17-hydroxyprogesterone, androstenedione, estradiol, and aldosterone were measured before and after cosyntropin administration (ie, ACTH; 5 microg/kg [2.27 microg/lb], IM). Liver biopsy specimens from 16 dogs (11 with and 5 without hyperphosphatasemia) were evaluated histologically., Results: In dogs with hyperphosphatasemia, the corticosteroid ALP isoform comprised a significantly higher percentage of total ALP activity, compared with the percentage in dogs without hyperphosphatasemia (mean +/- SE, 69 +/- 5.0% and 17 +/- 3.8%, respectively). In 6 dogs with hyperphosphatasemia, but none without, serum cortisol concentrations exceeded reference intervals after ACTH stimulation. Six dogs with and 15 without hyperphosphatasemia had increased concentrations of >or = 1 noncortisol steroid hormone after ACTH stimulation. Serum ALP activity was correlated with cortisol and androstenedione concentrations (r = 0.337 and 0.496, respectively) measured after ACTH stimulation. All dogs with and most without hyperphosphatasemia had abnormal hepatocellular reticulation typical of vacuolar hepatopathy. Subjectively, hepatocellular reticulation was more severe and widespread in hyperphosphatasemic dogs, compared with that in nonhyperphosphatasemic dogs., Conclusions and Clinical Relevance: Hyperphosphatasemia in apparently healthy Scottish Terriers was most likely attributable to hyperadrenocorticism on the basis of exaggerated serum biochemical responses to ACTH administration and histologic hepatic changes, but none of the dogs had clinical signs of hyperadrenocorticism.

Background: Chronic vomiting is a common problem in dogs that has many causes. Ultrasonographic descriptions of many gastrointestinal (GI) diseases have been published. However, diagnostic utility of ultrasonography in dogs with chronic vomiting has not been investigated., Hypothesis: Diagnostic utility of abdominal ultrasound will be highest in dogs with GI neoplasia and lowest in those with inflammatory disorders., Animals: Eighty-nine pet dogs with chronic vomiting., Methods: Medical records were reviewed and the contribution of abdominal ultrasound to the clinical diagnosis was subjectively scored., Results: In 68.5% of dogs, the reviewers thought that the same diagnosis would have been reached without performing ultrasonography. In 22.5% of dogs, the ultrasound examination was considered to be vital or beneficial to the diagnosis. Univariable analysis identified that increased diagnostic utility was associated with increasing age, a greater number of vomiting episodes per week, presence of weight loss, a greater percentage of lost body weight, and a final diagnosis of GI lymphoma or gastric adenocarcinoma. However, multivariate analysis only identified increasing age and a final diagnosis of gastric adenocarcinoma or GI lymphoma to be associated with increased diagnostic utility. In 12.4% of dogs, additional benefits of ultrasonography to case management, excluding the contribution to the vomiting problem, were identified., Conclusions and Clinical Importance: The diagnostic utility of abdominal ultrasonography was high in 27% of dogs. The presence of factors that are associated with high diagnostic utility is an indication to perform abdominal ultrasonography in dogs with chronic vomiting.

Background: Sterile nodular panniculitis (SNP) is an uncommon inflammatory condition of subcutaneous fat that can be idiopathic, but has also been associated with underlying conditions such as pancreatic disease or systemic lupus erythematosus (SLE). The pathogenesis and clinical course of the condition are not well understood., Objectives: To retrospectively review cases of SNP associated with systemic signs, concurrent disease, or both and characterize the clinical, laboratory, imaging, and histopathologic findings, treatment, and response to treatment., Animals: Fourteen dogs with histologically confirmed SNP diagnosed between 1996 and 2008., Methods: Retrospective study., Results: Skin lesions were ulcerated or draining nodules in 9 dogs and nonulcerative subcutaneous nodules in 5. Most dogs had systemic signs, such as fever, inappetence, lethargy, and multiple lesions. Common clinicopathologic findings included neutrophilia with or without left shift, increased alkaline phosphatase activity, mild hypoglycemia, hypoalbuminemia, and proteinuria. Concurrent diseases included pancreatic disease, SLE, rheumatoid arthritis, polyarthritis, lymphoplasmacytic colitis, and hepatic disease. Dogs responded to immunosuppressive doses of corticosteroids when administered. Prognosis for recovery was related to the underlying disease process., Conclusions and Clinical Importance: SNP is not a single disease. Rather, it is a cutaneous marker of systemic disease in many cases. After thorough evaluation for concurrent disease and infectious causes, immunosuppressive treatment is often effective.

Background: Hypothyroidism affects renal function in a manner opposite the effects of hyperthyroidism., Objective: To evaluate the effects of experimentally induced hypothyroidism on glomerular filtration rate (GFR) and basal plasma creatinine concentration in dogs., Animals: Sixteen anestrous, female dogs., Methods: Hypothyroidism was induced by administration of (131)I in 8 dogs, and 8 healthy euthyroid dogs acted as controls. Exogenous plasma creatinine clearance (an estimate of GFR) was measured in all dogs before (control period) and 43-50 weeks after induction of hypothyroidism (posttreatment period). Other pharmacokinetic parameters of creatinine were also determined., Results: No significant difference was observed for basal plasma creatinine concentration and creatinine clearance between control and hypothyroid dogs in the control period. In the posttreatment period, mean + or - SD creatinine clearance in the hypothyroid group (2.13 + or - 0.48 mL/min/kg) was lower (P < .001) than that of the control group (3.20 + or - 0.42 mL/kg/min). Nevertheless, basal plasma creatinine concentrations were not significantly different between the hypothyroid and control groups (0.74 + or - 0.18 versus 0.70 + or - 0.08 mg/dL, respectively) because endogenous production of creatinine was decreased in hypothyroid dogs (22 + or - 3 versus 32 + or - 5 mg/kg/d, P=.001)., Conclusion and Clinical Importance: Hypothyroidism causes a substantial decrease in GFR without altering plasma creatinine concentrations, indicating that GFR evaluation is needed to identify renal dysfunction in such patients.

Background: Eosinophilic inflammation of the gastrointestinal tract of dogs occurs in numerous disorders, typically resulting in diffuse intestinal thickening. Rarely, eosinophilic masses have been reported., Objective: Describe a series of dogs with 1 or more idiopathic eosinophilic gastrointestinal masses (IEGM) to better characterize the clinical features, treatment, and prognosis., Animals: Seven dogs with 1 or more gastrointestinal masses composed primarily of eosinophilic infiltrates for which no underlying cause was found., Methods: Retrospective case series., Results: Rottweilers and purebred, large breed dogs predominated. Dogs were middle-aged and typically had chronic signs of upper or lower gastrointestinal disease. Decreased appetite, vomiting, and evidence of gastrointestinal hemorrhage were present in the majority of cases. An abdominal or rectal mass was frequently noted on physical examination. Common laboratory abnormalities included peripheral eosinophilia, mature neutrophilia, hypoproteinemia, and hypocholesterolemia. The masses were histologically composed of moderate to severe eosinophilic infiltrates, which were often transmural and accompanied by fibrosis. All dogs treated with surgery alone died of complications of their disease. Treatment with corticosteroids and ivermectin improved clinical signs, caused resolution of eosinophilic infiltrates, and prolonged survival in most dogs treated medically., Conclusions and Clinical Importance: These findings suggest that the prognosis for dogs with IEGM may be good when recognized and managed appropriately. When surgery is performed, medical treatment should also be added.

Objective: To study the effects of experimentally induced hypothyroidism on skeletal muscle and characterize any observed myopathic abnormalities in dogs., Animals: 9 female, adult mixed-breed dogs; 6 with hypothyroidism induced with irradiation with 131 iodine and 3 untreated control dogs., Procedures: Clinical examinations were performed monthly. Electromyographic examinations; measurement of plasma creatine kinase, alanine aminotransferase, aspartate aminotransferase, lactate, and lactate dehydrogenase isoenzyme activities; and skeletal muscle morphologic-morphometric examinations were performed prior to and every 6 months for 18 months after induction of hypothyroidism. Baseline, 6-month, and 18-month assessments of plasma, urine, and skeletal muscle carnitine concentrations were also performed., Results: Hypothyroid dogs developed electromyographic and morphologic evidence of myopathy by 6 months after treatment, which persisted throughout the study, although these changes were subclinical at all times. Hypothyroid myopathy was associated with significant increases in plasma creatine kinase, aspartate aminotransferase, and lactate dehydrogenase 5 isoenzyme activities and was characterized by nemaline rod inclusions, substantial and progressive predominance of type I myofibers, decrease in mean type II fiber area, subsarcolemmal accumulations of abnormal mitochondria, and myofiber degeneration. Chronic hypothyroidism was associated with substantial depletion in skeletal muscle free carnitine., Conclusions and Clinical Relevance: Chronic, experimentally induced hypothyroidism resulted in substantial but subclinical phenotypic myopathic changes indicative of altered muscle energy metabolism and depletion of skeletal muscle carnitine. These abnormalities may contribute to nonspecific clinical signs, such as lethargy and exercise intolerance, often reported in hypothyroid dogs.

The purpose of this study was to evaluate the safety and effect of iopanoic acid in 13 cats with hyperthyroidism induced by daily subcutaneous administration of 25microg/kg levothyroxine for a period of 42 days. On day 28 of levothyroxine administration, cats were randomly allocated to receive treatment twice daily with a placebo (control group; n=4), 50mg iopanoic acid (low dose group; n=5), or 100mg iopanoic acid (high dose group; n=4) for 14 days. Compared to the control group, T(3) concentrations were significantly decreased in both the low dose and high dose groups on days 35 and 42. T(3) concentrations in the low dose and high dose groups at days 35 and 42 were not different from day -8. The effect of iopanoic acid on clinical signs of hyperthyroidism was less apparent. Further clinical studies evaluating the long-term effect in cats with spontaneous hyperthyroidism are warranted.

Background: Anesthesia and surgery affect thyroid function tests in humans but have not been studied in dogs., Hypothesis: Anesthesia and anesthesia with surgery will affect thyroid function tests in dogs., Animals: Fifteen euthyroid dogs., Methods: Prospective, controlled, interventional study. Dogs were assigned to one of 3 groups: control, general anesthesia, and general anesthesia plus abdominal exploratory surgery. Dogs in the anesthesia and surgery groups were premedicated with acepromazine and morphine, induced with propofol, and maintained on isoflurane. Samples for measurement of serum thyroxine (T4), free T4 (fT4) by equilibrium dialysis, triiodothyronine (T3), reverse T3 (rT3), and thyroid-stimulating hormone concentrations were collected from each dog immediately before premedication, at multiple times during anesthesia, surgery, 4, 8, 12, 24, 36, and 48 hours after anesthesia, once daily for an additional 5 days, and once 14 days after anesthesia. Sampling was performed at identical times in the control group., Results: Serum T4 decreased significantly from baseline in the surgery and anesthesia groups compared with the control group at 0.33 (P= 0.043) and 1 hour (P= 0.018), and 2 (P= 0.031) and 4 hours (P= 0.037), respectively, then increased significantly in the surgery group compared with the control group at 24 hours (P= 0.005). Serum T3 decreased significantly from baseline in the anesthesia group compared with the control group at 1 hour (P= 0.034). Serum rT3 increased significantly from baseline in the surgery group compared with the control and anesthesia groups at 8 (P= 0.026) and 24 hours (P= 0.0001) and anesthesia group at 8, 12, 24, and 36 hours (P= 0.004, P= 0.016, P= 0.004, and P= 0.014, respectively). Serum fT4 increased significantly from baseline in the surgery group compared to the control at 24 hours (P= 0.006) and at day 7 (P= 0.037) and anesthesia group at 48 hours (P= 0.023)., Conclusions and Clinical Importance: Surgery and anesthesia have a significant effect on thyroid function tests in dogs.

Hypothyroidism in bitches has been reported to cause a variable interestrus interval, infertility, abortion, and stillbirth. The objective of this study was to evaluate the effect of experimentally induced hypothyroidism in bitches on fertility, pregnancy, parturition, and neonatal health. Eighteen healthy multiparous bitches were used; hypothyroidism was induced (by radioiodine administration) in nine bitches and the remaining nine served as untreated controls. After breeding, bitches were evaluated for pregnancy, fetal resorption, gestation length, litter size, duration and strength of uterine contractions (during parturition), interval between delivery of pups, viability of pups at birth, periparturient survival, and weight of pups at birth through 4 weeks of age. Bitches were bred a median of 19 weeks after induction of hypothyroidism. All bitches became pregnant and delivered term litters. There was no difference in the interestrus interval, litter size, or gestation length between hypothyroid and control bitches. Duration of uterine contractions was longer, but contraction strength was weaker in hypothyroid than control bitches; however, the interval between delivery of pups was not affected. Periparturient puppy mortality was significantly higher in litters from hypothyroid bitches. Viability scores and weight at birth were significantly lower in pups from hypothyroid bitches than controls. There was no difference between groups in pup weight gain during the first 4 weeks, in the interval from birth to the eyes opened, or to the onset of walking. Although hypothyroidism of relatively short duration did not affect fertility, it prolonged parturition and reduced pup survival in the periparturient period.

Background: With the exception of myxedema coma, central nervous system signs are rare in hypothyroid dogs., Hypothesis: Central vestibular dysfunction is a possible and reversible manifestation of hypothyroidism., Animals: Medical records of dogs with vestibular dysfunction and hypothyroidism were reviewed. Of 113 records identified, 10 dogs with at least 2 concurrent clinical neurologic abnormalities localizable to the central vestibular system were included., Methods: Retrospective, descriptive study., Results: Median age at diagnosis was 7 years (range, 5-10 years). All dogs were referred for progressive neurologic disease. Lesions were localized to the myelencephalic region in 5 dogs and to the vestibulocerebellum in 5 dogs. Two dogs had evidence of multifocal intracranial disease. Non-neurologic physical abnormalities suggestive of hypothyroidism were absent in 7 of 10 dogs. Hypercholesterolemia was the only consistent clinicopathologic abnormality detected, and was present in 7 of 10 dogs. All dogs had total thyroxine (TT4) and free thyroxine (fT4) concentrations below reference ranges, and 9 of 10 had increased TSH concentrations. Intracranial imaging studies were normal in 5 of 8 dogs, and identified lesions consistent with infarctions in 3 of 8 dogs. Albuminocytologic dissociation was detected in 5 of 6 CSF analyses. Brainstem auditory-evoked responses disclosed prolonged wave V latencies in 3 of 4 dogs tested. No other causes of central vestibular dysfunction were identified during other diagnostic investigations. The median time from initiation of treatment to clinical improvement was 4 days. Vestibular signs resolved in 9 of 10 dogs within 4 weeks., Conclusions and Clinical Importance: Although the pathogenesis in dogs without evidence of infarction is unknown, central vestibular dysfunction appears to be a rare but reversible neurologic sequelae of hypothyroidism.

Objective: To evaluate the effects of deracoxib and aspirin on serum concentrations of thyroxine (T4), 3,5,3'-triiodothyronine (T3), free thyroxine (fT4), and thyroid-stimulating hormone (TSH) in healthy dogs., Animals: 24 dogs., Procedure: Dogs were allocated to 1 of 3 groups of 8 dogs each. Dogs received the vehicle used for deracoxib tablets (PO, q 8 h; placebo), aspirin (23 to 25 mg/kg, PO, q 8 h), or deracoxib (1.25 to 1.8 mg/kg, PO, q 24 h) and placebo (PO, q 8 h) for 28 days. Measurement of serum concentrations of T4, T3, fT4, and TSH were performed 7 days before treatment (day -7), on days 14 and 28 of treatment, and 14 days after treatment was discontinued. Plasma total protein, albumin, and globulin concentrations were measured on days -7 and 28., Results: Mean serum T4, fT4, and T3 concentrations decreased significantly from baseline on days 14 and 28 of treatment in dogs receiving aspirin, compared with those receiving placebo. Mean plasma total protein, albumin, and globulin concentrations on day 28 decreased significantly in dogs receiving aspirin, compared with those receiving placebo. Fourteen days after administration of aspirin was stopped, differences in hormone concentrations were no longer significant. Differences in serum TSH or the free fraction of T4 were not detected at any time. No significant difference in any of the analytes was detected at any time in dogs treated with deracoxib., Conclusions and Clinical Relevance: Aspirin had substantial suppressive effects on thyroid hormone concentrations in dogs. Treatment with high dosages of aspirin, but not deracoxib, should be discontinued prior to evaluation of thyroid function.

Increased serum alkaline phosphatase (ALKP) activity in dogs is commonly encountered. In the study reported here, 7 Scottish Terriers were identified with hyperphosphatasemia, for which a cause could not be determined. The clinicopathologic findings of the syndrome are described and correlated with hepatic pathologic changes in biopsy specimens and in specimens obtained at postmortem examination. Five of the 7 dogs were related. The ALKP activity ranged from 1.7 to 17 times the reference value at the time of biopsy. Increased ALKP activity was present for >6 months in 2 dogs and >12 months in 5 dogs; activity was > 1,000 U/L for at least 1 measurement in 5 dogs. Results of liver function testing, adrenocortical function testing, and hepatic ultrasonography were reviewed. Results of histological examination were normal in 6 dogs. One dog had regional, chronic cholangitis without evidence of cholestasis. The lesion was judged unlikely to account for the degree of hyperphosphatasemia. This study provides evidence of possible benign hyperphosphatasemia in Scottish Terriers or of another familial disorder causing asymptomatical hyperphosphatasemia without corresponding histopathological abnormalities in the liver. Prospective studies of ALKP isoenzyme characterization, investigation of skeletal integrity, evaluation of additional related dogs to determine prevalence, and longer follow-up evaluation are necessary to better characterize this finding.

Objectives: To measure urine concentrations of sulfated glycosaminoglycans (GAGs), determine optimal storage conditions for urine samples, establish a reference range, and determine whether there is correlation between 24-hour total urine GAG excretion and the GAG-to-creatinine ratio (GCR)., Animals: 14 healthy adult dogs., Procedure: Single urine sample GAG concentrations and GCRs were measured in samples collected from 14 healthy dogs at the start of the 24-hour collection period. Twenty-four-hour total urine GAG excretions were determined from urine collected during a 24-hour period in the same 14 dogs. Total sulfated GAG concentrations were also measured in urine from these dogs after the urine had been stored at 4 degrees C and -20 degrees C for 1, 7, and 30 days., Results: Urine GAG concentrations were not significantly different from baseline values after urine was stored at 4 degrees C for up to 1 day and -20 degrees C for up to 30 days. Neither single urine sample GAG concentration (R2, 0.422) nor GCR (R2, 0.084) was an adequate predictor of 24-hour total urine GAG excretion., Conclusions and Clinical Relevance: Results of this study provide data that can be used to establish a reference range for 24-hour total urine GAG excretion in dogs and adequate conditions for sample storage. Contrary to findings in humans, there was no significant linear correlation between 24-hour total urine GAG excretion and single urine sample GCR in dogs, limiting clinical use of the single urine sample test.

The objective of this study was to evaluate the safety and efficacy of a purified porcine insulin zinc suspension for treating dogs with uncomplicated diabetes mellitus. Fifty-three dogs were treated for 60 days after an initial dose determination period. The means of the blood glucose concentrations during 12-hour glucose curves and the means of the blood glucose nadir concentrations during 12-hour glucose curves for all dogs were determined before beginning insulin therapy (time 0), at the end of the dose determination period (time 1), 30 days after time 1 (time 2), and 60 days after time 1 (time 3). Presence of polyuria, polydipsia, and ketonuria was determined at each time point. Adequacy of control of hyperglycemia was based on 12-hour blood glucose curves and improvement in clinical variables (results of physical examinations, historic information, polyuria, polydipsia, and ketonuria). Safety was evaluated by questionnaire, performance of physical examination, CBC, serum chemistry profile, and urinalysis. The means of the blood glucose concentrations during 12-hour glucose curves and the means of the blood glucose nadir concentrations during 12-hour glucose curves for all dogs at times 1, 2, and 3 were significantly lower compared with time 0 (P < .0001). There was a reduction in the proportion of dogs with polyuria, polydipsia, and ketonuria of 82, 86, and 80%, respectively. All of the dogs had adequate glycemic control at time 1, 66% at time 2, and 75% at time 3. At time 3, 66% of dogs required insulin injections q12h. Other than hypoglycemia, there were no important adverse effects of insulin administration. The insulin, was safe and efficacious for reducing blood glucose and clinical signs in dogs with diabetes mellitus.

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.

In humans, pancreatic hyperechogenicity and duct dilation are reported as normal aging changes. Similar changes have been reported with pancreatitis in the cat. We attempted to determine if aging changes occur in the ultrasound appearance of the normal feline pancreas. The pancreas of 84 normal (based on history, physical exam, biochemical profile, and feline trypsin-like immunoreactivity and pancreatic lipase immunoreactivity concentrations) cats of varying ages was scanned. Pancreatic width at the left limb and body, pancreatic duct diameter at left limb and body, and pancreatic echogenicity compared with liver and surrounding fat were noted and compared with age and body weight. Lower and upper limits of the 95% reference intervals for pancreatic left limb width were 2.6 and 9.5 mm, and 3.5 and 8.5 mm for the pancreatic body width. There was no significant difference in pancreatic width between the left limb and body. Lower and upper limits of the 95% reference interval for the diameter of the pancreatic duct at the left limb and body were similar, and were 0.65 and 2.5 mm. There was a weak but significant linear correlation between pancreatic duct diameter and age, with increasing pancreatic duct diameter with increasing age. There was no correlation of pancreatic width with age, and no correlation of pancreatic echogenicity with age or body weight. Based on this study, feline pancreatic size and echogenicity do not change with age. Pancreatic duct diameter increases slightly with age and should not be used as a sole indicator of pancreatitis in the geriatric cat.

Hypertension is a common complication of canine hyperadrenocorticism. Increased pressor sensitivity to endogenous catecholamines is currently believed to be the main mechanism involved in the development of hypertension in human hyperadrenocorticism. The aim of this study was to evaluate pressor sensitivity to norepinephrine in dogs after induction of iatrogenic hyperadrenocorticism (I-HAC) by serial arterial blood pressure measurements during infusions of increasing dose rates of norepinephrine (0.1, 0.15, 0.2, 0.3, 0.4, 0.6, and 0.8 microg/kg/min) in eight dogs with I-HAC and eight control dogs. Systolic, diastolic, mean blood pressure and heart rate measurements were recorded. The changes in these parameters between the two groups of dogs were compared. Dogs in the I-HAC group had a more pronounced pressor response to norepinephrine infusions than control dogs since the infusions had to be stopped in seven of the dogs due to severe hypertension (>240 mmHg). The mean maximum tolerated dose rate in the control group was 0.6 microg/kg/min with a standard error of 0.0 and 0.34 microg/kg/min with a standard error of 0.08 in the I-HAC group. The study demonstrated the presence of increased pressor sensitivity to norepinephrine in dogs with I-HAC.