Use of octreotide for the treatment of protein-losing enteropathy in dogs: Retrospective study of 18 cases.

BACKGROUND: More than 50% of dogs with protein-losing enteropathy (PLE) fail to respond to standard therapies. Octreotide, a somatostatin analogue, is used in cases of intestinal lymphangiectasia (IL) in humans with some success. OBJECTIVES: Describe the use of octreotide in dogs with PLE including reason for and details of prescription, adverse effects, and apparent response. ANIMALS: Eighteen dogs with PLE, 13 with histopathology available. Ninety-two percent (12/13) had IL diagnosed on biopsy. All 13 dogs had intestinal inflammatory infiltrates noted. METHODS: Multicenter, retrospective, descriptive study. Cases were volunteered for inclusion by individual attending veterinarians who reported the use of octreotide in cases of PLE. RESULTS: In 16/18 (89%) cases octreotide was prescribed to PLE dogs with a clinical suspicion or confirmed diagnosis of IL that were refractory to standard therapies. Median serum albumin at the time of octreotide prescription was 1.7 g/dL (range, 1.0-3.1 g/dL). The median dose of octreotide prescribed was 20 µg/kg, SQ, daily with a range of 4-39 µg/kg, SQ, daily. Adverse effects were noted in 3/18 (17%, 95% CI [4%, 41%]) of dogs; discontinuation of the drug was necessary in 1 dog. Improvement in clinical signs was noted in 6/12 (50%, 95% CI [21%, 79%]). CONCLUSIONS AND CLINICAL IMPORTANCE: Octreotide was most commonly prescribed to dogs with PLE and suspected or confirmed IL that had failed to respond to standard therapies. Though a benefit to PLE dogs cannot be confirmed, octreotide was well tolerated by the majority of dogs at the doses prescribed in this study.

Gastric pH and serum gastrin concentration in age-matched healthy dogs and dogs with chronic kidney disease.

BACKGROUND: Gastric hyperacidity and hypergastrinemia are purported to cause gastric ulceration in dogs with chronic kidney disease (CKD); however, no published studies have evaluated gastric pH with serum gastrin concentrations in dogs with CKD. HYPOTHESIS: To compare mean intragastric pH, mean percent pH distribution, and serum gastrin concentrations in dogs with CKD to age-matched, healthy dogs. We hypothesized there would be no difference in mean gastric pH or serum gastrin between groups. ANIMALS: Thirteen dogs with CKD; 10 aged-matched healthy dogs. METHODS: Prospective, case-control study. Serum chemistry, complete blood count, urinalysis, and serum gastrin concentrations were evaluated in all dogs before radiographic-assisted gastric placement of a pH capsule. Forty-eight-hour continuous gastric pH monitoring was performed in all dogs. Serum gastrin concentration, mean pH, and mean percentage time that gastric pH was strongly acidic (pH <1 and pH <2) were compared between groups using a repeated measures mixed-model ANOVA. RESULTS: No significant differences were observed between groups for any pH measurements, including mean ± SD gastric pH (CKD, 2.37 ± 0.87; healthy, 2.39 ± 0.99; P > .05). Serum gastrin concentrations were not significantly different between groups (median [range]: CKD, 10.5 ng/dL [<10-17.1]; healthy, 10.9 ng/dL [<10-15]; P > .05). CONCLUSIONS AND CLINICAL IMPORTANCE: Our client-owned dogs with CKD did not have lower gastric pH or higher serum gastrin concentrations compared to healthy dogs. Our results suggest that prophylactic gastric acid suppression in dogs with CKD is not warranted unless other clinical indications for use are present.

The use of metronidazole in acute diarrhea in dogs: a narrative review.

Acute diarrhea is a common reason for non-wellness veterinary visits in dogs. Treatment for acute diarrhea usually consists of supportive care with nutritional intervention, fluid therapy, anthelmintics, and often an antibiotic - commonly metronidazole in North America. The empirical use of metronidazole for acute diarrhea in dogs has been a common practice in veterinary medicine for many decades; however, recent studies evaluating its use suggest it may be inappropriately utilized in many cases. Herein, we review the evidence evaluating the use of metronidazole and other antibiotics in acute diarrhea in the human and veterinary literature. Recommendations on the use of metronidazole and other antibiotics as well as other therapeutic considerations in the treatment of acute diarrhea are also provided.

Effect of esomeprazole with and without a probiotic on fecal dysbiosis, intestinal inflammation, and fecal short-chain fatty acid concentrations in healthy dogs.

BACKGROUND: Proton pump inhibitors can cause diarrhea and a transient increase in fecal dysbiosis index in dogs. It is unknown if concurrent probiotic administration mitigates these effects. OBJECTIVE/HYPOTHESIS: To assess the fecal Canine Microbial Dysbiosis Index (CMDI), fecal short chain fatty acid (SCFA), and fecal calprotectin concentrations in dogs administered esomeprazole with and without a probiotic. ANIMALS: Eleven healthy dogs. METHODS: Prospective, within-subjects before and after study. All dogs received 7-day courses of esomeprazole (1 mg/kg PO q 24h) alone followed by esomeprazole with a probiotic (15 billion CFU/kg), separated by a 4-week washout period. Data were compared between phases using mixed effects ANOVA or generalized estimating equations with post-hoc Holm adjustment for 2-way comparisons. RESULTS: Compared to baseline (mean CMDI -2.66, SD 3.04), fecal CMDI was not different with esomeprazole administration alone (mean CMDI -1.48, SD 3.32, P = .08), but there was a significant increase (Diff 3.05, 95% CI [1.37, 4.74], P < .001, Effect size 2.02) when esomeprazole and a probiotic were administered concurrently (mean CMDI 0.39, SD 2.83). CMDI was significantly higher when esomeprazole was administered with a probiotic than alone (Diff 1.87, 95% CI [0.19, 1.87], P = .02, Effect size 1.24). Fecal calprotectin and SCFA concentrations did not differ between phases. The occurrence of vomiting and diarrhea was not different from baseline when esomeprazole was administered alone (36%/27%) or with a probiotic (46%/9%). CONCLUSIONS AND CLINICAL IMPORTANCE: In healthy dogs, concurrent administration of a probiotic is unlikely to lessen adverse effects associated with esomeprazole administration.

Impact of fatty acid composition on markers of exocrine pancreatic stimulation in dogs.

Chronic pancreatitis in dogs is typically managed with a low-fat diet. Human research suggests that consumption of medium-chain triglycerides (MCT) may lessen pancreatic enzyme release compared to consumption of long-chain fatty acids (LCFA). Twelve healthy adult colony dogs were fed a meal of cod and rice with either 3% metabolizable energy (ME) fat (control), high MCT (25% ME MCT oil, 25% ME butter), high saturated LCFA (50% ME butter), or high unsaturated LCFA (50% ME canola oil) in a 4-period by 4-treatment crossover design. Serum concentrations of canine pancreatic lipase immunoreactivity, gastrin, cholesterol, triglycerides, and serum activities of amylase and DGGR lipase (1,2-o-dilauryl-rac-glycero-3-glutaric acid-(69-methylresorufin) ester lipase) were measured at times 0 (fasted), 30, 120 and 180 minutes post-prandially. Following a 3-or 4-day wash-out period, each dog was assigned a new diet and the process was repeated for all treatments. Data were analyzed as a repeated-measures mixed model ANOVA. Post-hoc pairwise comparisons were run using Tukey-Kramer adjusted p-values. Shapiro-Wilk tests were used to evaluate residual normality. All statistical assumptions were sufficiently met. Statistical significance was defined as P<0.05. Of the markers tested, only serum triglyceride concentrations were affected by treatment, with consumption of high MCT resulting in lower triglycerides than both LCFA groups at times 120 and 180 minutes (P<0.0001). As expected, the high MCT group had higher triglycerides compared to the control group (P<0.0001). The type of dietary fat consumed had little acute impact on most markers of exocrine pancreatic stimulation in healthy dogs.

Correlation between Targeted qPCR Assays and Untargeted DNA Shotgun Metagenomic Sequencing for Assessing the Fecal Microbiota in Dogs.

DNA shotgun sequencing is an untargeted approach for identifying changes in relative abundances, while qPCR allows reproducible quantification of specific bacteria. The canine dysbiosis index (DI) assesses the canine fecal microbiota by using a mathematical algorithm based on qPCR results. We evaluated the correlation between qPCR and shotgun sequencing using fecal samples from 296 dogs with different clinical phenotypes. While significant correlations were found between qPCR and sequencing, certain taxa were only detectable by qPCR and not by sequencing. Based on sequencing, less than 2% of bacterial species (17/1190) were consistently present in all healthy dogs (n = 76). Dogs with an abnormal DI had lower alpha-diversity compared to dogs with normal DI. Increases in the DI correctly predicted the gradual shifts in microbiota observed by sequencing: minor changes (R = 0.19, DI < 0 with any targeted taxa outside the reference interval, RI), mild-moderate changes (R = 0.24, 0 < DI < 2), and significant dysbiosis (R = 0.54, 0.73, and 0.91 for DI > 2, DI > 5, and DI > 8, respectively), compared to dogs with a normal DI (DI < 0, all targets within the RI), as higher R-values indicated larger dissimilarities. In conclusion, the qPCR-based DI is an effective indicator of overall microbiota shifts observed by shotgun sequencing in dogs.

Double-blinded placebo-controlled clinical trial of prophylactic omeprazole in dogs treated surgically for acute thoracolumbar intervertebral disc extrusion.

BACKGROUND: Proton pump inhibitors are administered prophylactically in dogs treated surgically for acute thoracolumbar intervertebral disc extrusion (TL-IVDE). However, their efficacy in decreasing gastrointestinal (GI) complications is unknown. HYPOTHESIS: Omeprazole does not decrease the frequency of GI complications compared to placebo in dogs treated surgically for acute TL-IVDE. ANIMALS: Thirty-seven client-owned dogs undergoing hemilaminectomy for acute TL-IVDE. METHODS: Randomized double-blinded placebo-controlled prospective clinical trial. Dogs received PO placebo or omeprazole at 1 mg/kg q12h for 5 days during hospitalization. Development of GI signs (e.g., diarrhea, vomiting, regurgitation, hematochezia, melena) was recorded daily. Clinicopathologic testing performed during hospitalization and at 2 and 4-week re-evaluations included: fecal occult blood, PCV, blood urea nitrogen/creatinine ratio, fecal calprotectin, canine pancreatic lipase immunoreactivity and fecal alpha-1 proteinase inhibitor concentrations. Omeprazole and placebo groups were compared using chi-squared or Fisher's exact tests. RESULTS: Gastrointestinal signs developed in 10/20 (50%) dogs in the omeprazole group and in 7/17 (41%) dogs in the placebo group (P = .59). Diarrhea was common (8/20 omeprazole, 5/17 placebo), hematochezia was rare (1/20 omeprazole, 1/17 placebo); melena was not observed. Clinicopathologic evidence suggestive of bleeding was present in 9/20 dogs treated with omeprazole and in 11/17 dogs that received placebo (P = .23). Fecal occult blood positivity was more common in dogs with GI signs (P = .03). Canine pancreatic lipase immunoreactivity was higher during hospitalization compared to re-evaluations (P = .01). CONCLUSIONS AND CLINICAL IMPORTANCE: Short-term, prophylactic omeprazole treatment did not decrease clinically detectable GI complications in dogs with acute TL-IVDE.

Esomeprazole induces structural changes and apoptosis and alters function of in vitro canine neoplastic mast cells.

Histamine-2 receptor antagonists such as famotidine and proton pump inhibitors such as esomeprazole are commonly used in canine MCT disease, but direct effects on dog MCs have not been evaluated. Omeprazole is a proton pump inhibitor which has been demonstrated to cause structural and functional changes to in vitro murine mast cells (MCs). It has not yet been determined if esomeprazole, the commercially available and commonly prescribed S-isomer of omeprazole, has similar effects. Our primary study objective was to evaluate and compare the effects of acid suppressants (esomeprazole and famotidine) on MC ultrastructure, viability, and function in vitro using both healthy and neoplastic MCs. Murine bone marrow derived mast cells (BMMC), human LAD2, and canine C2 and BR cells, were used for these studies, representing a single healthy (i.e., BMMCs) MC model and multiple neoplastic MC models (i.e., LAD2, C2, BR), respectively. The rat basophilic leukemic (RBL-2H3) and canine B cell lymphoma 17-71 cell lines served as granulocytic and agranulocytic control lines for experiments, respectively. The treatment effect of acid suppressants on MC ultrastructure was assessed via both light and transmission electron microscopy. Differences in MC viability was assessed between groups via MTS-based, colorimetric assays and flow cytometry. Degranulation was assessed by quantification of ß-hexosaminidase (i.e., LAD2 and RBL-2H3). Esomeprazole-treated MCs of all lines exhibited dramatic time and concentration-dependent alterations in ultrastructure (i.e., increased vacuolization, compromise of cell membrane), increased apoptosis, and altered degranulation responses in comparison to famotidine and vehicle-treated cells. The canine B cell lymphoma cells consistently exhibited either no significant (i.e., cytotoxicity assays) or greatly diminished treatment responses (i.e., apoptosis) compared to MCs. Esomeprazole, but not famotidine, induces significant cytotoxicity, as well as alterations to cell structure and function to multiple lines of in vitro neoplastic MCs. Continued in vitro work investigating the specific mechanisms by which proton pump inhibitors induce these effects, as well as prospective, in vivo work comparing the treatment effects of acid suppressants on canine MCTs, are warranted.

Clinical utility of an immunoglobulin A-based serological panel for the diagnosis of chronic enteropathy in dogs.

BACKGROUND: A panel of IgA-based serologic assays might aid in the diagnosis of chronic enteropathy (CE) in dogs, a syndrome encompassing conditions such as food-responsive enteropathy, immunosuppressant-responsive enteropathy, and inflammatory bowel disease (also referred to as chronic inflammatory enteropathy). However, it is unclear whether these biomarkers discriminate between CE and other types of primary intestinal disorders. OBJECTIVES: To evaluate a diagnostic panel that measures serum concentrations of IgA directed against OmpC (ACA), canine calprotectin (ACNA), and gliadin-derived peptides (AGA) in dogs with well-characterized intestinal diseases. ANIMALS: Fifty-five dogs with primary intestinal disease. METHODS: Serum ACA, ACNA, and AGA concentrations were measured in 30 dogs with CE and 25 dogs with other intestinal diseases (non-CE population), including histoplasmosis, parasitism, E. coli-associated granulomatous colitis, and lymphoma. Serum IgA concentrations were compared among populations, and sensitivities and specificities were calculated using laboratory-provided cut-points. RESULTS: Twenty-six of 30 (87%) CE dogs and 21 of 25 (84%) non-CE dogs had abnormal concentrations (intermediate or high) of at least 2 markers; these proportions were not significantly different (P = .99). A serum ACA concentration ≥15 EU/mL was 86.7% (95% confidence interval [CI], 69.3%-96.2%) sensitive and 24.0% (95% CI, 9.4%-45.1%) specific for CE diagnosis. High AGA concentrations were observed in 16 of 25 (64%) non-CE dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: The evaluated serologic markers were poorly specific for CE diagnosis, which raises concerns that their use in clinical practice might lead to misdiagnoses and delayed or even detrimental treatments in dogs with non-CE intestinal diseases.

Demographic factors associated with joint supplement use in dogs from the Dog Aging Project.

Osteoarthritis (OA) is one of the most prevalent age-related chronic conditions that afflict companion dogs, and multiple joint supplements are available to prevent or treat OA, though the efficacy of these treatments is controversial. While the demographic factors that are associated with OA diagnosis are well established, the factors that are associated with joint supplement use are not as well studied. Using data collected from the Dog Aging Project, we analyzed owner survey responses regarding joint supplement administration and OA diagnosis for 26,951 adult dogs. In this cross-sectional analysis, logistic regression models and odds-ratios (OR) were employed to determine demographic factors of dogs and their owners that were associated with joint supplement administration. Forty percent of adult dogs in our population were given some type of joint supplement. Perhaps not surprisingly, dogs of older age, larger size, and those that were ever overweight were more likely to receive a joint supplement. Younger owner age, urban living, owner education, and feeding commercial dry food were associated with a reduced likelihood of administration of joint supplements to dogs. Interestingly, mixed breed dogs were also less likely to be administered a joint supplement (OR: 0.73). Dogs with a clinical diagnosis of OA were more likely to receive a joint supplement than those without a reported OA diagnosis (OR: 3.82). Neutered dogs were more likely to have a diagnosis of OA, even after controlling for other demographic factors, yet their prevalence of joint supplement administration was the same as intact dogs. Overall, joint supplement use appears to be high in our large population of dogs in the United States. Prospective studies are needed to determine if joint supplements are more commonly administered as a preventative for OA or after an OA clinical diagnosis.

Development and evaluation of a survey instrument to assess veterinary medical record suitability for multi-center research studies.

Here we describe the development and evaluation of a survey instrument to assess the research suitability of veterinary electronic medical records (EMRs) through the conduct of two studies as part of the Dog Aging Project (DAP). In study 1, four reviewers used the instrument to score a total of 218 records in an overlapping matrix of pairs to assess inter-rater agreement with respect to appropriate format (qualification), identification match (verification), and record quality. Based upon the moderate inter-rater agreement with respect to verification and the relatively large number of records that were incorrectly rejected the instrument was modified and more specific instructions were provided. In study 2, a modified instrument was again completed by four reviewers to score 100 different EMRs. The survey scores were compared to a gold standard of board-certified specialist review to determine receiver operating curve statistics. The refined survey had substantial inter-rater agreement across most qualification and verification questions. The cut-off value identified had a sensitivity of 95 and 96% (by reviewer 1 and reviewer 2, respectively) and a specificity of 82% and 91% (by reviewer 1 and reviewer 2, respectively) to predict gold standard acceptance or rejection of the record. Using just qualification and verification questions within the instrument (as opposed to full scoring) minimally impacted sensitivity and specificity and resulted in substantial time savings in the review process.

Gastrointestinal transit time is faster in Beagle dogs compared to cats.

OBJECTIVE: To characterize gastrointestinal transit times (GITTs) and pH in dogs, and to compare to data recently described for cats. ANIMALS: 7 healthy, colony-housed Beagles. PROCEDURES: The GITTs and pH were measured using a continuous pH monitoring system. For the first period (prefeeding), food was withheld for 20 hours followed by pH capsule administration. Five hours after capsule administration, dogs were offered 75% of their historical daily caloric intake for 1 hour. For the second period (postfeeding), food was withheld for 24 hours. Dogs were allowed 1 hour to eat, followed by capsule administration. Both periods were repeated 3 times. The GITTs and pH were compared to published feline data. RESULTS: The mean ± SD transit times in dogs for the pre- and postfeeding periods, respectively, were esophageal, 3 ± 5 minutes and 13 ± 37 minutes; gastric, 31 ± 60 minutes and 829 ± 249 minutes; and intestinal, 795 ± 444 minutes and 830 ± 368 minutes. The mean ± SD gastrointestinal pH in dogs for the pre- and postfeeding periods, respectively, were esophageal, 6.6 ± 0.6 and 5.7 ± 1.0; gastric, 3.0 ± 1.4 and 1.8 ± 0.3; intestinal, 7.9 ± 0.3 and 7.7 ± 0.6; first-hour small intestinal, 7.6 ± 0.5 and 7.1 ± 0.4; and last-hour large intestinal, 7.9 ± 0.6 and 7.7 ± 1.0. The first-hour small intestinal pH and total transit times varied between dogs and cats depending on feed period (P = .002 and P = .04, respectively). Post hoc analysis revealed significantly shorter total transit times in dogs prefeeding (P = .005; mean ± SD for cats, 2,441 ± 1,359 minutes; for dogs, 828 ± 439 minutes) and postfeeding (P = .03; mean ± SD for cats, 3,009 ± 1,220 minutes; for dogs, 1,671 ± 513 minutes). Total transit time for dogs was also shorter pre- versus postfeeding (P = .003). CLINICAL RELEVANCE: GITT is faster in Beagles compared to cats, but gastrointestinal pH are similar when fed the same diet.

Evaluation of proton pump inhibitor administration in hospitalized dogs in a tertiary referral hospital.

BACKGROUND: Although proton pump inhibitors (PPIs) are commonly administered to hospitalized dogs, prescribing patterns and appropriateness of use require continued investigation. HYPOTHESIS/OBJECTIVE: Describe prescription patterns and appropriateness of use associated with PPIs in hospitalized dogs at a single tertiary care facility. We hypothesized that the majority of prescriptions would not comply with current guidelines for the rational use of acid suppressants. ANIMALS: Two hundred randomly selected hospitalized dogs. METHODS: Retrospective evaluation of the medical records associated with a randomly selected sample of hospitalized dogs that received PPIs between January 2013 and December 2018. RESULTS: A total of 12 610 dogs were admitted for first-time hospitalization between January 2013 and December 2018. Forty percent of these dogs (5062/12610) were prescribed a PPI PO or IV. Of the 200 randomly selected records, an adequate indication for use was identified in 27% of dogs (54/200). Of the dogs surviving to discharge, 54% (95/175) were discharged with a PPI and 51.6% (49/95) of those were prescribed an inadequate dose. CONCLUSIONS AND IMPORTANCE: Our findings support other studies in which the majority of PPI prescriptions for hospitalized dogs at a tertiary care hospital lacked an appropriate indication. Furthermore, analysis of the prescribing patterns of dispensed PPIs identified a frequent occurrence of dosages considered inadequate, raising concern for ineffective treatment even with appropriate indications of use. With growing concern of adverse effects associated with PPI and other acid suppressant administration in human and veterinary medicine, rational use of these medications following consensus guidelines should be emphasized and treatment should be reserved for dogs with historical, physical examination, clinicopathologic, and imaging findings supportive of an appropriate indication for use.

Evaluation of a long-acting injectable formulation of omeprazole in healthy dogs.

BACKGROUND: To evaluate the efficacy of a single intramuscular adminsitration of long-acting omeprazole (LA-OMEP) in increasing gastric pH in dogs. HYPOTHESIS: We hypothesized that LA-OMEP would meet in healthy dogs the clinical goals defined for human patients for treatment of gastroduodenal ulceration. ANIMALS: Nine healthy research dogs. METHODS: Prospective experimental study. Dogs were given a 4 mg/kg intramuscular injection of LA-OMEP. Intragastric pH was continuously recorded on treatment days 0 to 7. Daily mean pH and mean percentage time (MPT) intragastric pH was ≥3 or ≥4 were determined. RESULTS: The mean onset of action for the LA-OMEP was 98.11 min (SD 46.39). The mean number of days the dogs' pH met established goals for MPT pH ≥3 was 5.5 days (range, 3-7) and 5.25 days for MPT pH ≥4 (range, 3-7). Long-acting omeprazole met the human clinical goals pH ≥3 for 72 hours in 8/8 of the dogs and MPT pH ≥4 for 96 hours in 7/8 of dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: The LA-OMEP formulation produced gastric acid suppression in healthy dogs for an average of 5 days and up to 7 days, after a single intramuscular injection. No major adverse effects were observed.

Once-daily feeding is associated with better health in companion dogs: results from the Dog Aging Project.

A variety of diets have been studied for possible anti-aging effects. In particular, studies of intermittent fasting and time-restricted feeding in laboratory rodents have found evidence of beneficial health outcomes. Companion dogs represent a unique opportunity to study diet in a large mammal that shares human environments. The Dog Aging Project has been collecting data on thousands of companion dogs of all different ages, sizes, and breeds since 2019. We leveraged this diverse cross-sectional dataset to investigate associations between feeding frequency and cognitive function (n = 10,474) as well as nine broad categories of health conditions (n = 24,238). Controlling for sex, age, breed, and other potential confounders, we found that dogs fed once daily rather than more frequently had lower mean scores on a cognitive dysfunction scale, and lower odds of having gastrointestinal, dental, orthopedic, kidney/urinary, and liver/pancreas disorders. Therefore, we find that once-daily feeding is associated with better health in multiple domains. Future research with longitudinal data can provide stronger evidence for a possible causal effect of feeding frequency on health in companion dogs.

Esophageal varices in dogs: A retrospective case series.

BACKGROUND: Esophageal varices (EV) are abnormally dilated veins in the esophagus caused by alterations of blood flow or pressure. Esophageal variceal hemorrhage is a major complication of hepatic disease in humans, but a lack of information exists regarding associated adverse events in dogs. OBJECTIVE: To describe the clinical manifestations and associated etiologies and outcomes of dogs with EV. ANIMALS: Twenty-five client-owned dogs with EV diagnosed via computed tomography (CT), endoscopy, or fluoroscopy. METHODS: Retrospective case series. Cases were identified by review of the hospital imaging records database between 2010 and 2020. Signalment, clinical signs, and outcomes were documented. When present, additional collateral vasculature was also recorded. Cases were subcategorized into suspected etiology based upon the anatomic location or absence of an attributable underlying disease process, as well as the direction of blood flow. RESULTS: Twenty-four of 25 cases were identified via CT, with a prevalence of 0.012% (24/1950 total studies). Presenting clinical signs were nonspecific, and more likely because of the underlying cause as opposed to complications secondary to EV themselves. Etiologic anatomic locations were similar in occurrence between the abdomen (N = 14) and thorax (N = 11). All cases with an abdominal etiologic location had presumed or confirmed portal hypertension and 9/11 cases with a thoracic etiologic location had pulmonary, caval, or systemic hypertension. No cases died or were euthanized as a direct result of EV or associated hemorrhage. CONCLUSIONS AND CLINICAL IMPORTANCE: Esophageal varices are rarely reported in dogs and commonly identified concurrently with portal, pulmonary, and caval hypertension. Hemorrhage is not a common clinical manifestation of EV.

Correlation of cytology to histology in a case of canine granulomatous colitis in a Boxer dog.

A 2-year-old castrated male mixed breed dog presented to the North Carolina State Veterinary Teaching Hospital for chronic diarrhea with hematochezia and weight loss. Cytology performed on a rectal scraping revealed macrophages containing magenta, light pink, and variably blue granular inclusions, and phagocytosed material concerning for infectious organisms. Histopathology was consistent with granulomatous colitis and identified intra-histiocytic bacterial organisms, confirmed by fluorescent in situ hybridization (FISH)-tissue culture-confirmed Escherichia coli. Based on these findings, a diagnosis of granulomatous colitis was made. The patient was successfully treated with oral enrofloxacin, and near-complete remission of signs was achieved within 6 weeks. This report describes a case of granulomatous colitis in a mixed breed dog, and is the first published description of the cytologic features of this uncommon disease, offering a valuable cytologic-histologic correlation. In this case, the cytology was helpful in identifying features consistent with granulomatous colitis and prioritizing the differential diagnoses and diagnostic plan.

Clinical Features and Risk Factors for Gastrointestinal Complications in Dogs Treated Surgically for Thoracolumbar Intervertebral Disc Extrusion.

Gastrointestinal (GI) complications and their clinical implications are poorly characterized in dogs treated surgically for acute thoracolumbar intervertebral disc extrusion (TL-IVDE). The objective of this retrospective study was to characterize GI signs (including vomiting, diarrhea, melena, and hematochezia) in dogs undergoing hemilaminectomy for acute TL-IVDE. One-hundred and sixteen dogs were included. Frequency, type and severity of GI signs during hospitalization, duration of hospitalization and outcome were obtained from the medical record. Potential risk factors for the development of GI signs were explored using univariable and multivariable analyses. Gastrointestinal signs occurred in 55/116 dogs (47%); 22/55 dogs (40%) had one episode and 21/55 (38%) had ≥5 episodes. Diarrhea was the most common (40/55, 73%) while melena was rare (1/55, 2%). GI signs developed in 8/11 dogs (73%) treated perioperatively with both non-steroidal anti-inflammatories and corticosteroids with or without a washout period and in 25/52 dogs (48%) treated prophylactically with proton pump inhibitors. Median hospitalization was 7 days (4-15 days) vs. 5 days (4-11 days) in dogs with or without GI signs, respectively. Duration of hospitalization was associated with development of any GI signs, diarrhea and more severe GI signs (p = 0.001, 0.005, 0.021, respectively). Pre-operative paraplegia with absent pain perception was identified on univariable analysis (p = 0.005) and longer anesthetic duration on multivariable analysis to be associated with development of more severe GI signs (p = 0.047). In dogs undergoing surgery for acute TL-IVDE, GI signs were common and associated with duration of hospitalization and anesthesia. The influence of specific medications and neurologic severity on development of GI signs requires further investigation.