Multiplate platelet aggregometry in dogs undergoing laparoscopic liver biopsy for diagnosis of chronic hepatopathy.

OBJECTIVES: To assess platelet function via the Multiplate analyser in dogs undergoing laparoscopic liver biopsy for diagnosis of chronic hepatopathy. MATERIALS AND METHODS: Twenty-seven client-owned dogs were prospectively enrolled. Before laparoscopic liver biopsy, whole blood impedance platelet aggregometry via the Multiplate analyser was performed. Buccal mucosal bleeding time was performed in 23 of 27 dogs. Tissue factor-activated thromboelastography was also performed, in addition to plasma-based coagulation testing. Descriptive statistics were calculated and the prevalence of platelet function abnormalities and results of other biochemical and coagulation testing were reported. RESULTS: Seventeen (63%) of 27 dogs had evidence of decreased platelet function as assessed by aggregometry, with all 17 dogs having decreased responsiveness to adenosine diphosphate, and 11 of 17 dogs demonstrating decreased responsiveness to arachidonic acid. Based on maximum amplitude, most dogs were classified as normocoagulable on thromboelastography (15/25; 60%). Other frequent coagulation abnormalities included increased D-dimers (20/27;74%), thrombocytopenia (11/27; 41%), hypofibrinogenemia (4/27; 15%), and decreased antithrombin (4/27; 15%). CLINICAL SIGNIFICANCE: Decreased platelet function as assessed by whole blood impedance aggregometry was common in dogs with chronic liver disease. Further study is necessary to determine whether this finding is repeatable or indicative of increased bleeding risk.

Prospective evaluation of a change in dietary therapy in dogs with steroid-resistant protein-losing enteropathy.

OBJECTIVE: To describe the clinical effect of dietary alteration as a sole change to therapy in dogs with steroid-resistant protein-losing enteropathy. MATERIALS AND METHODS: Prospective study. Eligible enrolled dogs received dietary alteration as sole change to their therapeutic plan. Canine Chronic Enteropathy Clinical Activity Index and serum albumin were monitored for the 3-month study period. Long-term follow-up data were also available for some of the study participants. RESULTS: Fifteen dogs were eligible for enrollment over the study period. Twelve were enrolled, 10 remained in the study at 30 days, nine completed the 3-month study period. Following dietary alteration, eight of 10 dogs achieved complete remission, one dog achieved partial remission and one dog had no response. Seven of eight dogs achieving complete remission have remained in remission up to 4 years following study. In dogs with complete remission, median Canine Chronic Enteropathy Clinical Activity Index score was 11.5 and 4, and median serum albumin concentration was 15 g/L and 26 g/L at 0 and 14-28 days, respectively. CLINICAL SIGNIFICANCE: Dogs with protein-losing enteropathy with previous lack of response to a combination of dietary therapies, glucocorticoids and immunosuppressive medications can achieve remission following a dietary change. Improvement is likely to be seen within 14 to 30 days. A change in dietary approach may be an alternative to further immunosuppression or anti-inflammatory strategies in some dogs with difficult to treat protein-losing enteropathy.

Eubacterial fluorescence in situ hybridisation and histologic features in 25 dogs with gallbladder mucocele.

OBJECTIVES: To detect and localise bacteria in gallbladder mucoceles using fluorescence in situ hybridisation (FISH). To report clinical signs, clinicopathologic abnormalities, sonographic findings and histopathological findings in FISH+ and FISH- dogs with gallbladder mucoceles. MATERIALS AND METHODS: Retrospective review of signalment, clinical signs, clinicopathologic and sonographic findings of 25 cases of histopathologically confirmed gallbladder mucocele. Histopathological sections of gallbladder mucocele were evaluated for cystic mucinous hyperplasia, cystic mucinous hyperplasia with cholecystitis and rupture. The number and spatial distribution of bacteria was determined by eubacterial FISH. Gallbladder contents were cultured in 21 dogs. RESULTS: Bacteria were detected within or adherent to the gallbladder wall in eight of 25 (32%) cases. Bacterial culture was positive in one dog. Cystic mucinous hyperplasia with concurrent cholecystitis was found in 17 of 25 (68%) of dogs with gallbladder mucocele. CLINICAL SIGNIFICANCE: FISH was more sensitive for detection of bacteria in gallbladder mucoceles when compared to bacterial culture of bile. Cholecystitis was common in dogs with gallbladder mucocele. Further study is required to elucidate the relationship of cystic mucinous hyperplasia, bacteria and cholecystitis in the aetiopathogenesis and progression of gallbladder mucocele.

Histopathologic Characteristics of Intestinal Biopsy Samples from Dogs With Chronic Inflammatory Enteropathy With and Without Hypoalbuminemia.

BACKGROUND: Previous studies have identified hypoalbuminemia as a risk factor for negative outcome in dogs with chronic enteropathy (CE), but it has not been determined whether histopathology differs between CE dogs with and without hypoalbuminemia. OBJECTIVE: To compare histopathologic findings in dogs with biopsy-diagnosed inflammatory CE with and without hypoalbuminemia. ANIMALS: 83 dogs that had intestinal biopsy performed between January 2010-July 2015. Dogs had signs compatible with CE of at least 3-weeks' duration and no evidence of clinically relevant extra-gastrointestinal (GI) disease or potential non-GI causes of hypoalbuminemia. Dogs had primary diagnosis of inflammatory enteritis based on histopathology. METHODS: Dogs were grouped into CE with normoalbuminemia (CEN; serum albumin concentration ≥3.0 g/dL, N = 46) or chronic enteropathy with hypoalbuminemia (CEH; serum albumin concentration <3.0 g/dL, N = 37). A pathologist (SLP) blinded to the groups reviewed biopsy samples and applied the World Small Animal Veterinary Association scoring system to all samples. RESULTS: Intestinal biopsy samples from dogs in the CEH group were significantly more likely to display villous stunting, epithelial injury, crypt distension, and lacteal dilatation, and were more likely to have intraepithelial lymphocytes and lamina propria neutrophils than biopsy samples from dogs in the CEN group. Additionally, higher scores for each of the above listed histopathologic criteria were associated with a lower serum albumin concentration. CONCLUSIONS AND CLINICAL IMPORTANCE: Histopathologic features of chronic inflammatory enteropathy differ between dogs that are hypo- versus normoalbuminemic. Additional work is needed to elucidate the clinical relevance of these differences.

A Homozygous RAB3GAP1:c.743delC Mutation in Rottweilers with Neuronal Vacuolation and Spinocerebellar Degeneration.

BACKGROUND: A variety of presumed hereditary, neurologic diseases have been reported in young Rottweilers. Overlapping ages of onset and clinical signs have made antemortem diagnosis difficult. One of these diseases, neuronal vacuolation and spinocerebellar degeneration (NVSD) shares clinical and histological features with polyneuropathy with ocular abnormalities and neuronal vacuolation (POANV), a recently described hereditary disease in Black Russian Terriers (BRTs). Dogs with POANV harbor mutations in RAB3GAP1 which codes for a protein involved in membrane trafficking. HYPOTHESIS: Rottweilers with NVSD will be homozygous for the RAB3GAP1:c.743delC allele associated with POANV in BRTs. ANIMALS: Eight Rottweilers with NVSD confirmed at necropsy, 128 Rottweilers without early onset neurologic signs, and 468 randomly selected dogs from 169 other breeds. METHODS: Retrospective case-control study. Dogs were genotyped for the RAB3GAP1:c.743delC allele with an allelic discrimination assay. RESULTS: All 8 NVSD-affected dogs were homozygous for the RAB3GAP1:c.743delC allele while the 128 NVSD-free Rottweilers were either homozygous for the reference allele (n = 105) or heterozygous (n = 23) and the 468 genotyped dogs from other breeds were all homozygous for the reference allele. CONCLUSIONS AND CLINICAL IMPORTANCE: The RAB3GAP1:c.743delC mutation is associated with a similar phenotype in Rottweilers and BRTs. Identification of the mutation permits a DNA test that can aid in the diagnosis of NVSD and identify carriers of the trait so that breeders can avoid producing affected dogs. Disruption of membrane trafficking could explain the neuronal vacuolation seen in NVSD and other spongiform encephalopathies.

Vaccine-associated Leptospira antibodies in client-owned dogs.

BACKGROUND: Long-term microscopic agglutination test (MAT) results after vaccination with 4-serovar Leptospira vaccines are not available for all vaccines used in client-owned dogs. HYPOTHESIS/OBJECTIVES: To determine antibody responses of client-owned dogs given 1 of 4 commercially available Leptospira vaccines. ANIMALS: Healthy client-owned dogs (n = 32) with no history of Leptospira vaccination for at least the previous year. METHODS: Dogs were given 1 of 4 Leptospira vaccines on week 0 and then approximately on week 3 and week 52. Sera were collected before vaccine administration on week 0 and then within 3 days of week 3, within 2 days of week 4, and approximately on weeks 7, 15, 29, 52, and 56. Antibody titers against Leptospira serovars bratislava, canicola, grippotyphosa, hardjo, icterohemorrhagiae, and pomona and were determined by MAT. RESULTS: When compared among vaccines, MAT results varied in maximal titers, the serovars inducing maximal titers, and the time required to reach maximal titers. Each vaccine induced at least some MAT titers ≥1 : 800. Most dogs were negative for antibodies against all serovars 1 year after vaccination, and anamnestic responses were variable. CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs vaccinated with Leptospira vaccines have variable MAT titers over time, and antibodies should not be used to predict resistance to Leptospira infection. MAT titers ≥1 : 800 can develop after Leptospira spp. vaccination, which can complicate the clinical diagnosis of leptospirosis.