VTechWorks Repository :: Browsing by Author "Leib, Michael S."

Browsing by Author "Leib, Michael S."

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Bile duct obstruction associated with pancreatitis in 46 dogs
Wilkinson, Ashley R.; DeMonaco, Stefanie M.; Panciera, David L.; Otoni, Cristiane C.; Leib, Michael S.; Larson, Martha M. (Wiley, 2020)
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.
Body composition of dogs determined by carcass composition analysis, deuterium oxide dilution, subjective and objective morphometry, and bioelectrical impedance
Burkholder, William Joseph (Virginia Tech, 1994-05-16)
Prediction of body composition was assessed in thirty-eight female and thirty-seven male random source dogs using in vivo methods of deuterium oxide dilution, subjective and objective morphometry, bioelectrical impedance and ultrasound, either separately or in various combinations. Carcass composition determined by chemical analyses of carcass homogenates served as criterion measures of body composition. Dogs were selected based on gender, body weight and body condition score. Body weight ranged from 7.3 to 34.5 kilograms (kg), subdivided into 4.5 kg increments with 6 female and 6 male dogs per increment. Body condition was categorized as thin, optimum or obese using a defined criteria, body condition scoring system (subjective morphometry) with 12 female and 12 male dogs per body condition category. Selection criteria produced 18 body weight condition groups with 2 female and 2 male dogs per group. One additional male and 2 female dogs were included for economic and ethical reasons. Equations to predict carcass composition from in vivo measurements were derived using standard regression techniques. Influence diagnostics, residual analysis and data splitting were used to validate predictive equations. Predictions from deuterium oxide dilution produced the most precise estimates of body composition. Average standard errors of estimation (SEE) from deuterium equations were 1.3, 1.8, 1.0, and 0.4 percent for percentages of body moisture, fat, protein and ash, respectively, and 0.39, 0.57,0.21 and 0.08 kg for absolute quantities of moisture, fat, protein and ash, respectively. Morphometry produced the most imprecise, but economical, estimates. Average SEE from morphometry equations for proportions were 3.0, 4.0, 1.3, and 0.4 percent, and 0.9, 0.9, 0.3 and 0.07 kg for absolute quantities of moisture, fat, protein and ash, respectively. Subjective morphometry could estimate body fat with an average SEE of 3.4 percent and correctly categorized 75 percent of the dogs. Bioelectrical impedance and ultrasound produced predictions with average SEE intermediate to deuterium and morphometry. Bioelectrical impedance was equivalent to deuterium dilution on the basis of cost per unit improvement in SEE, but ultrasound was not cost effective.
Commercial diets do not affect the colonic ultrastructure of normal dogs
Campbell, Sharon Louise (Virginia Tech, 1993-06-10)
Commercial and homemade diets are currently used to treat many canine patients with acquired disorders of the colon. Clinically, the efficacy of diets has been found to be unpredictable. Only one study to date has evaluated the effect of diet on the colonic mucosa. This study showed that diet did not observably alter the colonic mucosa of normal dogs, when biopsy samples were evaluated by light microscopy. The effect of diet on colonic ultrastructure in the dog, using transmission electron microscopy, has not previously been investigated. To determine the effect of diet on colonic ultrastructure, cell height, cell area, microvillus height, number of microvilli/apex width and basement membrane width were measured. Ten cells per animal were evaluated. Six dogs were assigned to the control group and fed the control diet for the duration of the study. Six dogs were fed each of the three test diets at four week intervals. The test diets used included a high fiber diet, a hypoallergenic diet and a highly digestible diet. These diets were selected because they are the diets most often recommended for the canine patient with colonic disorders. The value for cell height for the highly digestible group was significantly greater than the other groups, as measured by ANOV A and Duncan's multiple comparison test. No other significant differences were found. The biological relevance of a significantly different value for cell height alone is difficult to evaluate, as other parameters that would indicate an alteration in maturation or proliferation of the colonic epithelial cells did not change. value for cell height alone is difficult to evaluate, as other parameters that would indicate an alteration in maturation or proliferation of the colonic epithelial cells did not change. Therefore, we conclude that commercial diets do not have an effect on the colonic ultrastructure of normal dogs. Although no effect of diet was found, this study does provide morphologic measurements that can be used as a basis for future ultrastructural studies of the colonic mucosa.
A Comparison of Liver Biopsy Techniques in Dogs
Kemp, Stephanie D. (Virginia Tech, 2013-05-15)
Background: The liver biopsy technique in dogs that consistently provides samples adequate for accurate histopathologic interpretation and the variability of histopathology among lobes is unknown. Hypothesis: Liver biopsy specimens obtained via punch, cup biopsy, and 14 gauge needle biopsy would result in similar histopathologic diagnoses to those found on deeply sectioned samples of liver obtained at necropsy and that discordant results would not differ between lobes. Animals: Seventy dogs undergoing necropsy. Methods: Liver specimens were obtained from the left lateral liver lobe with an 8 mm punch, a cup, and a 14 gauge needle. Two larger tissue samples were then collected near the center of the left lateral lobe and used as a histologic standard for comparison. Samples were also obtained from all remaining lobes. Histopathologic features and numbers of portal triads in each sample were compared. Results: The mean number of portal triads were 2.9 in needle biopsies, 3.4 in cup biopsies, 12 in punch biopsies, and 30.7 in the necropsy samples. Sixty-six percent of needle biopsies, 60% of laparoscopic cup samples, and 69% of punch samples were in agreement with the necropsy samples, differences that were not significantly different. The corresponding kappa coefficient were 0.59 for needle biopsies, 0.52 for cup biopsies, and 0.62 for punch biopsies. Discordant results did not differ between the liver lobes. Conclusions and Clinical Relevance: A single biopsy using any of the tested techniques is insufficient for reliable diagnosis of liver disease in the dog. Multiple biopsies from 2 lobes is recommended.
A Comparison of Liver Sampling Techniques in Dogs
Kemp, Stephanie D.; Zimmerman, Kurt L.; Panciera, David L.; Monroe, William E.; Leib, Michael S.; Lanz, Otto I. (American College of Veterinary Internal Medicine, 2015-01)
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.
Comparison of the Effects of Deracoxib, Buffered Aspirin, and Placebo on the Gastric Mucosa of Healthy Dogs
Sennello, Kathleen Ann (Virginia Tech, 2005-04-04)
This study tested the hypothesis that administration of deracoxib, a cyclooxygenase-2 specific (COX-2) inhibitor, would result in lower gastric lesion scores than administration of buffered aspirin and gastric lesion scores similar to placebo when administered to healthy dogs for 28 days. Twenty-four, healthy, random source dogs were divided into three groups. Group I received buffered aspirin, 23.6 mg/kg PO q 8h, group II received deracoxib, 1.6 mg/kg PO q 24h and placebo twice daily PO q 8h after deracoxib administration, and group III received placebo PO q 8h. Gastroscopy was performed on days -7, 6, 14, and 28 of treatment. Four regions of the stomach (pylorus, incisura, cardia, and body) were evaluated separately and lesions scored on a scale of 1 (mucosal hemorrhage) to 12 (perforating ulcer) by an observer unaware of which treatments the dogs received. Dogs were observed every 8 hours for vomiting, diarrhea and anorexia. Feces were scored from 1-5 (scores <4 were considered diarrhea). Lesion scores for each group, at each location, and total scores, at each time period, were evaluated for the effects of time and treatment using a Kruskal-Wallis test. Total dog days of vomiting and dog days of diarrhea in each group were compared using a Wilcoxon rank sums test. Significance was determined at p<0.05. Significantly higher median total gastric lesion scores were found in the aspirin group compared to the deracoxib or placebo groups on days 6, 14, and 28. There were no significant differences in median total gastric lesion scores between the deracoxib or placebo groups at any time during the study. There was no location effect on gastric lesion scores and there was no significant change in gastric lesion scores over time in any of the groups during treatment. Significantly more dog-days of vomiting occurred in the aspirin group as compared to the deracoxib group. No significant differences were found between groups for dog-days of diarrhea. In this study, the administration of deracoxib to healthy dogs resulted in significantly lower gastric lesion scores compared to dogs receiving aspirin and lesion scores similar to those receiving placebo.
Detecting Giardia: Clinical and Molecular Identification
Saleh, Meriam Naim (Virginia Tech, 2017-11-13)
The protozoan parasite Giardia duodenalis (syn. G. lamblia, G. intestinalis) can cause diarrhea in humans, cats, dogs and other animals. Giardia duodenalis consists of eight assemblages (A-H) that are morphologically identical but genetically distinct. Assemblages C-H are generally species-specific, while A and B infect people and animals and are considered potentially zoonotic. Most canine and feline isolates belong to their respective species-specific assemblages, but isolates of assemblages A and B (predominantly found in humans) have also been recovered from dogs and cats. Diagnosis of infection has historically been by morphologic techniques (observing trophozoites on direct fecal smears or cysts on centrifugal zinc sulfate fecal flotations), and it is currently recommended to use morphologic techniques in conjunction with a sensitive and specific antigen test. Diagnosis is important for management of clinical giardiasis in cats and dogs and also to identify the assemblage present to determine its zoonotic potential. In my dissertation research I evaluated diagnostic techniques in use for companion animals, including centrifugal zinc sulfate fecal flotation, antigen tests optimized for use in dogs and cats, direct immunofluorescent assay (IFA), and Polymerase Chain Reaction (PCR). I showed that when compared to the reference IFA the veterinary optimized antigen tests performed similarly and had no statistically significant differences in sensitivity or specificity when combined with a centrifugal zinc sulfate fecal flotation test. Sensitivity and specificity by comparison to IFA was ≥ 82% and ≥ 90%, respectively, for all diagnostic tests evaluated in dogs and cats. When analyzed via Bayesian analysis sensitivity and specificity for all diagnostic tests was ≥83% and ≥95%, respectively. The Bayesian analysis also showed that using the direct immunofluorescent assay (IFA) as the reference test was supported. I also evaluated PCR as a molecular diagnostic technique to detect Giardia infections in dogs with soft stool or diarrhea (mimicking clinical signs of infection). I utilized both conventional and real time PCR assays and compared the results to the recommended method of diagnosis, the zinc sulfate fecal flotation combined with an immunoassay test. I found that agreement between PCR and microscopy combined with an immunoassay was poor to fair and varied depending on the molecular parameters and size of the DNA target underscoring the complexity of test evaluation and molecular diagnostics for Giardia. I also evaluated cats from a varied population (owned, shelter, feral) in Virginia to determine to what extent (if any) they were infected with potentially zoonotic assemblages of Giardia. The species-specific assemblage F was detected in 57% of the samples and assemblage A, which is considered potentially zoonotic, was recovered from 32% of the sampleI. In 11% both assemblages F and A were detected. We showed for the first time that cats in Virginia are infected with potentially zoonotic assemblages of Giardia.
Effect of Dosing Interval on the Efficacy of Misoprostol in the Prevention of Aspirin-Induced gastric Injury in the Dog
Ward, Deborah Marie (Virginia Tech, 2000-03-27)
The effect of reduced frequency of administration of misoprostol on its ability to prevent aspirin-induced gastric injury was evaluated. Twenty-four random-source dogs were divided into 4 groups which received aspirin and misoprostol as follows: Group I, 25 mg/kg aspirin PO TID and placebo PO TID; Group II, 25 mg/kg aspirin PO TID and misoprostol 3 ug/kg PO TID; Group III, 25 mg/kg aspirin PO TID, misoprostol 3 ug/kg PO BID and placebo PO QD; and Group IV, 25 mg/kg aspirin PO TID, misoprostol 3 ug/kg PO QD and placebo PO BID for 28 days. Groups were stratified to contain an equal number of dogs positive or negative for Helicobacter spp. based on results of ‘CLO test’. Gastroscopy was performed on days –9, 5, 14 and 28. Each region of the stomach was evaluated separately and visible lesions were scored on a scale of 1 (submucosal hemorrhage) to 11 (perforating ulcer). The scores for each region were summed and the median total score for each group at each day and median total score within each group between days was compared using a Kruskal-Wallis test. No difference in total score was identified between Group I and IV on any day. Median total scores for Groups II and III were significantly(p < 0.05) lower compared to Groups I and IV on day 5. Significant difference was observed on Day 14 between the total score of Group III and Group IV. Group III had a significantly lower score (p < 0.05) than Groups I, II and IV on day 28. Gastric erosions were present in all groups in the study. This study suggests that misoprostol 3 ug/kg PO BID dosing is as effective as misoprostol 3 ug/kg PO TID dosing at preventing aspirin-induced gastric injury in this model. However, misoprostol 3 ug/kg PO TID dosing was less effective in preventing aspirin-induced gastric injury on days 14 and 28 than in previous studies. The lack of efficacy of TID dosing on days 14 and 28 may be related to higher salicylate concentrations in Group II dogs or individual variation within the small study population.
The effects of illness on urinary catecholamines and their metabolites in dogs
Cameron, Kristin Nicole (Virginia Tech, 2010-04-23)
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 is currently unknown. Objectives: To examine the effects of illness on urine concentrations of catecholamines and metanephrines in dogs. Animals: Twenty-five critically ill dogs and twenty-five healthy age- and gender-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 (HPLC) 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 to a healthy control population (P = 0.0009, P < 0.0001, P < 0.0001, and P < 0.0001 respectively). Conclusions and Clinical Relevance: 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.
Effects of Prednisone or Prednisone with Ultralow-Dose Aspirin on the Gastroduodenal Mucosa of Healthy Dogs
Graham, Allison Heather (Virginia Tech, 2009-03-20)
This study tested the hypothesis that administration of immunosuppressive doses of prednisone in conjunction with ultralow-dose aspirin (0.5 mg/kg/day) would result in gastroduodenal lesion scores similar to those found in dogs administered only immunosuppressive doses of prednisone, but that the gastroduodenal scores from both of these treatment groups would be significantly higher than placebo when administered to healthy dogs for 27 days. Eighteen healthy adult purpose-bred dogs were divided randomly into three groups. Group I received placebo capsules and placebo suspension, Group II received prednisone capsules (mean 2.3 mg/kg, range 2.0-2.4) and placebo suspension, and Group III received prednisone capsules (mean 2.3 mg/kg, range 2.3-2.5) and aspirin suspension (0.5 mg/kg) by mouth once daily for 27 days. Gastroduodenoscopy was performed on days -7 (baseline), 5, 14, and 27 of treatment. Four regions of the stomach (angularis incisura, body, pylorus, and cardia) and the proximal descending duodenum were systematically scored on a scale of 1 (normal) to 11 (perforating ulcer) by an experienced observer who was blinded to the treatment groups and clinical signs of each subject. Dogs were observed every 8 hours for vomiting, diarrhea, and inappetence. Feces were scored on a scale of 1-5 with diarrhea defined as a fecal score <4. Lesion scores for each group, at each location, and total scores, at each time period were evaluated for the effects of time and treatment using a Kruskal-Wallis test. Total dog days of vomiting and dog days of diarrhea in each group were compared using a Wilcoxon rank sums test. Significance was determined at p<0.05. There were no significant differences in median total gastric lesion scores between any of the groups at any time during the study. There was no location effect on regional gastroduodenal lesion scores and there was no significant change in gastroduodenal lesion scores over time in any of the groups during treatment. Significantly more dog-days of diarrhea occurred within the prednisone and aspirin group during the experimental period (Period 2) in comparison to Period 1. However, no significant differences were found between any of the groups for dog-days of vomiting, diarrhea or inappetence at any time in the study.
Efficacy of the Bromsulfophthalein (BSP) 30-Minute Retention Test for the Diagnosis of Hepatobiliary Disease in Dogs
Flatland, Bente (Virginia Tech, 1997-06-13)
Measuring the amount of bromsulfophthalein (BSP) retained in serum 30 minutes after intravenous injection can be used to evaluate hepatic function. BSP retention of less than 5% 30 minutes after intravenous administration is considered normal in dogs. The BSP retention test fell out of favor due to perceived inaccuracy when compared with bile acid and ammonia testing and a fear of hypersensitivity reactions. BSP was discontinued as a commercially-available drug in 1984. Use of BSP has continued at virginia tech despite the test's reputed disadvantages. The purpose of this study was to evaluate the efficacy of the BSP retention test in dogs with and without histopathologically-confirmed hepatobiliary disease. The medical records of 150 dogs with hepatobiliary disease having both a BSP retention test and hepatic biopsy performed were evaluated. Histopathologic slides were reviewed, and dogs were classified according to one of 11 predetermined histopathologic categories. Twenty-five random-source dogs were used as controls. Adverse effects following BSP administration were not observed in any dog. BSP retention was significantly different between hospitalized and control dogs, but the test could not distinguish between dogs with different types of hepatobiliary disease. Sensitivity, specificity, and predictive values of the BSP retention test were calculated, and its sensitivity was comparable to that of serum bile acid and ammonia testing. Using 6.0% retention as a cut-off for normal retention resulted in a specificity of 100%, sensitivity of 69.8%, positive predictive value of 100%, and negative predictive value of 35.7%.
Evaluation of pressor sentivity to norepinephrine infusion in dogs with iatrogenic hyperadrenocorticism
Martinez, Nivia Ivellise (Virginia Tech, 2002-04-15)
Objective: To evaluate pressor sensitivity to catecholamines in dogs after induction of iatrogenic hyperadrenocorticism (I-HAC) by serial arterial blood pressure measurements during infusions of increasing dose rates of norepinephrine. Animals: Eight dogs with I-HAC induced by administration of oral hydrocortisone at a mean dose of 3.3 mg/kg PO TID for 42-49 days and 8 control dogs which received empty gelatin capsules PO TID for 42-49 days. Procedure: Systolic, diastolic, mean blood pressure and heart rate measurements were recorded after sequential administration of increasing dose rates of norepinephrine (0.1, 0.125, 0.2, 0.3, 0.4, 0.6 and 0.8 mg/kg/min) for 10 minutes. The changes in systolic, diastolic, mean blood pressure and heart rate were compared between control dogs and dogs with I-HAC. Results: Dogs in the I-HAC group had a more pronounced pressor response to norepinephrine infusions than control dogs. The infusions were not completed in 7 of the 8 dogs in the I-HAC group versus 3 dogs in the control group due to severe elevations in systolic blood pressure. The mean change in systolic blood pressure was consistently higher in dogs in the I-HAC group. The difference was statistically significant at the 0.2 mg/kg/min norepinephrine dose rate. The mean change in heart rate was consistently lower in the I-HAC group, a difference that was significant at the 0.2 mg/kg/min norepinephrine dose rate. Conclusions and clinical relevance: Increased pressor sensitivity or decreased baroreceptor response to norepinephrine was seen in dogs with I-HAC suggesting that this mechanism is involved in the development of hypertension in canine hyperadrenocorticism.
The Gastroduodenal Effects of Buffered Aspirin, Carprofen, And Etodolac in the Healthy Dog and Comparison of the CLOtest® to Histopathologic Evaluation in Identifying the Presence of Helicobacter Spp. in Healthy Dogs
Reimer, Michele E. (Virginia Tech, 1999-02-24)
Twenty-four healthy, mixed breed dogs were divided into four groups. Group I received a placebo PO BID, group II received an average 16.5 (range, 15.1-17.8) mg/kg buffered aspirin PO BID, group III received an average 2.2 (range, 2.0-2.4) mg/kg carprofen PO BID, and group IV received an average 12.8 (range, 11.7-13.8) mg/kg etodolac PO QD (with a placebo in the P.M.). All treatments continued for 28 consecutive days. Gastroduodenal endoscopy was performed on days – 9, 0, 5, 14 and 28. Multiple gastric biopsies were obtained endoscopically on day – 9 to determine each dog's Helicobacter spp. status. Five areas, consisting of four regions in the stomach and one in the proximal duodenum, were evaluated endoscopically, and each was assigned a score from 1 to 11 based on qualitative assessment of submucosal hemorrhage, erosion, or ulceration. These scores for each region were then summed to give a total score for each endoscopic evaluation. Erosions and submucosal hemorrhages were seen in all dogs receiving aspirin. Only minor gastric lesions were observed in the carprofen, etodolac, and control groups. No adverse clinical signs were noted in any dog given any treatment during the course of the study. There was no predilection site for lesion development in any group. Median total score on days 0, 5, 14, and 28 were as follows: group I, 5.0, 5.0, 5.0, 5.0; group II, 5.0, 27.0, 26.0, 27.5; group III, 5.0, 5.0, 6.0, 5.0; group IV, 5.0, 7.0, 5.0, 5.0, respectively. There was no significant difference between dogs receiving carprofen, etodolac, or placebo. The administration of carprofen, etodolac, or placebo to healthy dogs resulted in significantly less gastroduodenal lesion development than in dogs receiving buffered aspirin. Thirty healthy, random source, dogs were evaluated to determine the prevalence of Helicobacter spp., and to compare the ‘Campylobacter-like organism’ test (CLOtest®) to histopathologic identification of Helicobacter spp. organisms. Gastric mucosal biopsies from each of four gastric regions (cardia, pyloric antrum, greater curvature, and angularis incisura) were obtained endoscopically for use in the CLOtest® and for histopathologic evaluation. Twenty-seven of 30 dogs (90%) were positive for spiral bacteria suspected to be Helicobacter spp. by histopathologic evaluation in at least one of the four gastric regions. Three dogs (10%) were negative for Helicobacter spp. in all gastric regions by histopathologic evaluation. The CLOtest® was found to have a sensitivity, specificity, and positive predictive value of 84%, 81%, and 92%, respectively, when compared to histopathologic evaluation. When only the angularis incisura was evaluated, the sensitivity, specificity, and positive predictive value increased to 92%, 94%, and 96%, respectively. The angularis incisura had the highest, whereas the pyloric antrum had the lowest, prevalence of positive test results when compared to dogs determined to be overall Helicobacter spp. positive (histopathologic positive in at least one gastric region). The results of this study suggest the prevalence of Helicobacter spp. in apparently healthy dogs is high. For accurate and economical detection of Helicobacter spp. in a dog undergoing upper gastrointestinal endoscopy, a tissue sample should be taken from the angularis incisura for CLOtest® sampling.
Histopathologic Variation between Liver Lobes in Dogs
Kemp, Stephanie D.; Zimmerman, Kurt L.; Panciera, David L.; Monroe, William E.; Leib, Michael S. (American College of Veterinary Internal Medicine, 2015-01)
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.
Natural History of Biliary Sludge in Dogs
Demonaco, Stefanie (Virginia Tech, 2015-08-27)
Background: Biliary sludge is associated with gallbladder (GB) dysmotility and mucus hypersecretion suggesting that these factors could lead to GB mucoceles. If biliary sludge does progress to GB mucoceles, treatments to reduce the production and progression of sludge are warranted. Objectives: The aim of this study was to determine the natural history of biliary sludge in dogs. Animals: Healthy, client-owned dogs (n=74) screened for biliary sludge; 42 affected dogs identified Methods: Prospective, observational design. Serial ultrasound examinations and biochemistries were evaluated over 1 year. The following were determined: percentage of the 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, GB dimensions, and biochemical indices (ALT, GGT, ALP, total bilirubin, albumin, total calcium, triglycerides, and cholesterol). Mixed model ANOVA, Friedman chi-square, Mantel-Haenzsel chi-square tests, and Kruskal-Wallis test were performed to detect significant changes in these parameters. Significance at P <0.05. Results: After 1 year of follow-up, the percentage of the GB filled by sludge was mild (34%), moderate (47%), moderate to severe (13%), severe (3%), or absent (3%) with no significant difference in the median degree of biliary sludge within 1 year (P=0.36). There was no significant change in the gravity dependency of sludge over 1 year. Dogs had resolved (2%), decreased (19%), static (40%), increased (29%), or recurrent (10%) sludge at the conclusion of the study. Biochemical indices or GB volume were not significantly different over time or among groups. Conclusion: Biliary sludge is prevalent, affected dogs remain asymptomatic, and it rarely resolves in healthy dogs over a period of 1 year. Some dogs developed non-gravity dependent sludge within 1 year, which may indicate changes in consistency.
Platelet Function in Dogs with Chronic Liver Disease
Wilkinson, Ashley R. (Virginia Tech, 2019-06-10)
Background: Dogs with acquired chronic liver disease often have hemostatic derangements. It is currently unknown whether dogs with acquired chronic liver disease have decreased platelet function and alterations in von Willebrand factor (vWF) that may contribute to hemostatic abnormalities. Hypothesis: Dogs with chronic liver disease have prolonged platelet closure time (CT), assessed with the PFA-100®, and buccal mucosal bleeding time (BMBT), and increased vWF concentration compared to healthy dogs. Animals: Eighteen dogs with chronic acquired liver disease undergoing ultrasound-guided needle biopsy of the liver or laparoscopic liver biopsy and eighteen healthy age-matched control dogs. Methods: Prospective study. BMBT, CT using the PFA-100®, and vWF antigen were measured in dogs with chronic liver enzyme elevation undergoing ultrasound-guided needle biopsy of the liver or laparoscopic liver biopsy. After undergoing ultrasound-guided needle biopsy, dogs were monitored for hemorrhage with serial packed cell volume measurements and focused assessment with sonography. An unpaired t-test was used for normally distributed data and the Mann-Whitney test was used when non-Gaussian distribution was present. The level of significance was set at P <0.05. Results: The CT was not different between the two groups (P = 0.27). The BMBT was significantly longer in the liver disease group compared to the control group (P = 0.019). There was no difference in the mean vWF antigen of the two groups (P = 0.077). Conclusions and clinical relevance: These results demonstrate mild impairment of primary hemostasis in dogs with chronic liver disease based on prolongation of BMBT.
The Safety and Efficacy of Oral Low-Volume Sodium Phosphate Bowel Preparation for Colonoscopy in Dogs
Daugherty, Megen Aileen (Virginia Tech, 2006-07-12)
Sodium phosphate (NaP) is a low-volume, hyperosmolar laxative that has been shown to be an effective bowel cleansing agent in people. The purposes of this study were to evaluate the safety and efficacy of oral NaP in dogs. Standard (NaP and enemas; NaP1) and control preparations (polyethylene glycol [PEG] and enemas) were compared in a crossover design to determine safety and efficacy of NaP. Serial clinical and serum analytical evaluations were used to determine the safety of NaP. The efficacy of the NaP1 preparation was compared to 3 NaP variations which excluded enema or included bisacodyl, with or without enemas in a crossover design. Eight dogs received each of 6 bowel preparations prior to colonoscopy performed one time per week. An observer blinded to the bowel preparation assigned a score of 1-4 (1 clean colon and ≥3 unacceptable preparation) to each of 5 regions of the colon. Mean total colon cleansing score (TCS), defined as the sum of scores from each region, of the control (9.4) was less than NaP1 (13.6) (p<0.05). There were no significant differences in regional or TCS for the remaining 4 NaP preparations. NaP1 resulted in moderate, but clinically occult, hyperphosphatemia and hypocalcemia, which resolved within 24 hours of initial administration. Despite the safety and ease of administration of the NaP preparations, the NaP bowel cleansing preparations used in this study cannot be recommended for routine clinical use due to the inadequate quality of bowel preparation compared to the PEG containing bowel cleansing protocol evaluated.
Spontaneous Course of Biliary Sludge Over 12 Months in Dogs with Ultrasonographically Identified Biliary Sludge
DeMonaco, Stefanie M.; Grant, David C.; Larson, Martha M.; Panciera, David L.; Leib, Michael S. (American College of Veterinary Internal Medicine, 2016-05)
Background: Biliary sludge is associated with gallbladder (GB) dysmotility and mucus hypersecretion suggesting a link between biliary sludge, and the formation of GB mucoceles (GMT). 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: Alter 1 year of follow-up, the degree of sludge was mild (34 %), moderate (47% moderate to severe. (13%), severe (30 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.

Browsing by Author "Leib, Michael S."

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