Clinical signs, histology, and CD3-positive cells before and after treatment of dogs with chronic enteropathies

Background: Histopathology is widely used for the diagnosis of inflammatory bowel disease in dogs. Variations in lesions and unavailability of uniform grading systems limit the usefulness of histologic examination.
Hypothesis: CD3 cell numbers in chronic enteropathies of dogs correlate with clinical activity of the disease and with severity of histopathologic changes.
Animals: Nineteen client-owned dogs examined because of chronic diarrhea, vomiting, or both.
Methods: Samples of duodenal and colonic mucosa were collected endoscopically before and after treatment. Dogs that responded to a hypoallergenic diet were grouped as food-responsive diarrhea dogs (FRD, n = 10). Dogs with no clinical improvement after 10 days of treatment then received prednisolone (immunosuppressive doses) and were grouped as steroid-responsive diarrhea dogs (SRD, n = 9). Histopathologic assessment with a standardized grading system was performed retrospectively on the intestinal samples. Histologic score, total number of infiltrating cells, and CD3-positive cells were counted and compared with the clinical scoring.
Results: No statistically significant difference was detected among histologic grading, total number of cells in the lamina propria, and T-cell numbers in biopsies before and after treatment in either group (FRD and SRD).
Conclusions and Clinical Importance: Currently used histopathologic grading scores, total numbers of cells, and numbers of CD3-positive cells did not allow differentiation between FRD and SRD and did not correlate with clinical response to therapy. Based on these results, new grading scores assessing other criteria than total cell numbers and CD3-positive cells should be evaluated in the future.     

RETROSPECTIVE STUDY EVALUATING ASSOCIATIONS BETWEEN MIDLINE BRAIN SHIFT ON MAGNETIC RESONANCE IMAGING AND SURVIVAL IN DOGS DIAGNOSED WITH MENINGOENCEPHALITIS OF UNKNOWN ETIOLOGY

Difficulty has been encountered when trying to identify ante mortem prognostic indicators for dogs with meningoencephalitis of unknown etiology (MUE). Identifying MRI imaging parameters associated with prognosis may impact treatment decision‐making for clinician and owner. Our hypotheses for this retrospective cohort study are that dogs diagnosed with MUE that had midline shift on brain MRI would have a poorer survival compared to dogs without midline shift; and that younger age, lower weight, and low cerebrospinal fluid (CSF) cell count would be correlated with improved survival. Medical records were reviewed from two institutions. Inclusion criteria included: clinical signs referable to intracranial disease, brain MRI at presentation, abnormal CSF analysis, and negative infectious disease testing. Magnetic resonance imaging scans were evaluated for midline shift using the T2‐weighted transverse image at the interthalamic adhesion and at the site of maximal deviation. Fifty‐two dogs met the inclusion criteria. Median midline deviation was 0.12 cm. Median survival for dogs with no shift was 906 days and with shift was 84 days. Survival was not significantly different between groups (P = 0.11). This remained true when correcting for age (P = 0.22) and CSF TNCC (total nucleated cell count) (P = 0.12). Age at the time of diagnosis (P = 0.02) and CSF TNCC (P = 0.03) were significantly associated with survival. Cerebrospinal fluid protein value (P = 0.84) and weight (P = 0.82) were not significantly associated with survival. In this study of 52 dogs with MUE, MRI evidence of midline brain shift between 0.04 and 0.3 cm at the level of the interthalamic adhesion was not associated with shorter survival.     

Use of oseltamivir in the treatment of canine parvoviral enteritis

Objective – To determine if oseltamivir with standard therapy for canine parvoviral enteritis ameliorates disease morbidity, mortality, or both; to document significant adverse effects associated with its use.
Design – Prospective, randomized, blinded, placebo-controlled clinical trial.
Setting – University veterinary teaching hospital.
Animals – Thirty-five dogs.
Interventions – Standard therapy was administered to all dogs. Treatment dogs also received oseltamivir, while control dogs received an equivalent volume of placebo.
Measurements and Main Results – Dogs were monitored daily according to a clinical scoring system, physical parameters, and diagnostic evaluations. Dogs in the treatment group gained a significant percentage of weight during hospitalization (mean, +2.6%; SD, 7.1%) versus the control dogs (mean, −4.5%; SD, 6.9%) ( P =0.006). Treatment dogs did not have any significant changes in their white blood cell (WBC) count, while control dogs experienced a significant drop in their WBC counts during their initial stay. In addition, it did not appear that oseltamivir use was associated with any major adverse clinical effects.
Conclusions – While a clear advantage to the use of oseltamivir was not established, a significant weight loss during hospitalization, as well as a significant decrease in WBC count were documented in the control group. No major adverse effects were identified that could be associated with oseltamivir administration. Based on these results, the true role of oseltamivir in the treatment of parvoviral enteritis remains speculative, although it is believed that further investigation is warranted.     

Effect of Pimobendan on Echocardiographic Values in Dogs with Asymptomatic Mitral Valve Disease

Background: Pimobendan (PIMO) is a novel inodilator that has shown promising results in the treatment of advanced mitral valve disease (MVD), but little is known about its hemodynamic effects, especially regarding the mitral regurgitant volume in naturally occurring MVD.
Hypothesis: The addition of pimobendan to treatment decreases the regurgitant fraction (RF) in dogs with asymptomatic MVD.
Animals: Twenty-four client-owned dogs affected by International Small Animal Cardiac Health Council class Ib MVD.
Methods: Prospective, blinded, and controlled clinical trial. Dogs were assigned to a PIMO treatment group (n = 19) (0.2–0.3 mg/kg q12h) or a control group (n = 5). Echocardiographic evaluations were performed over a 6-month period.
Results: The addition of PIMO to treatment did not decrease the RF of dogs affected by asymptomatic class 1b MVD over the study period ( P = .85). There was a significant increase in the ejection fraction of the PIMO treated dogs at 30 days (80.8 ± 1.42 versus 69.0 ± 2.76, corrected P = .0064), and a decrease in systolic left ventricular diameter (corrected P = .011) within the PIMO group compared with baseline. However, this improvement in systolic function was not sustained over the 6-month trial period.
Conclusion and Clinical Importance: This study did not identify beneficial long-term changes in the severity of mitral regurgitation after addition of PIMO to angiotensin converting enzyme inhibitor treatment of dogs with asymptomatic MVD.     

Chlorambucil and prednisolone chemotherapy for dogs with inoperable mast cell tumours: 21 cases

O bjectives : To evaluate the response of measurable canine mast cell tumours unsuitable for other treatment modalities to a chemotherapy protocol comprising chlorambucil and prednisolone.
M ethods : Dogs bearing measurable mast cell tumours, unsuitable for treatment by surgery or radiotherapy, were treated with orally administered prednisolone and chlorambucil, and their responses assessed.
R esults : Twenty-one dogs were enrolled in the study; 13 had intermediate-grade mast cell tumour, six were high grade and two were diagnosed by cytology alone. Eight dogs had multiple tumours and 13 dogs had single tumours, and six dogs had lymph node metastases and no dogs had visceral metastases detected. Three dogs achieved complete remission, five achieved partial remission (overall response rate 38 per cent), nine had static disease and four dogs had progressive disease. Median progression-free interval for the eight responders was 533 days, and median survival time for all dogs in the study was 140 days. Progression-free interval and median survival time were not influenced by the age, sex, weight or neutering status of the patient, by the grade or stage of the tumour or whether the patient had single or multiple tumours. No toxicity was detected.
C linical S ignificance : Response and survival rates of inoperable canine MCT to chlorambucil and prednisolone are comparable to previously described protocols, with no apparent toxicity.     

The effects of nitrous oxide on recovery from isoflurane anaesthesia in dogs

O bjectives : To assess rate and quality of recovery from anaesthesia where isoflurane was delivered in oxygen or oxygen/nitrous oxide.
M ethods : Dogs anaesthetised with propofol were randomly allocated to receive isoflurane maintenance in either 100 per cent oxygen (group 1) or 66 per cent nitrous oxide (N₂O)/34 per cent oxygen (group 2). Time from end of anaesthesia to achieving sternal recumbency was recorded. Incidence of adverse behaviours (vocalisation, uncontrolled head movement and restlessness) were assessed. Recovery quality was recorded on a visual analogue scale (VAS) (anchored at 0 with "best possible" recovery and "did not recover" at 100 mm). Age, weight, gender, anaesthetic duration, mean vaporiser setting, VAS scores, recovery times, postoperative temperature and behavioural scores were compared (chi-squared test, Mann-Whitney U test or t -test as appropriate, significance P≤0·05).
R esults : Objective data from 54 dogs were analysed, only VAS data where the observer was unaware of treatment group were used (n=33). Recovery was faster in group 2 dogs (median 10 min [range 4 to 31] compared with 14 minutes [3 to 43] in group 1, P=0·049) with less restlessness (0 [0 to 4] compared with 2 [0 to 4] in group 1, P=0·013) and uncontrolled head movement (0 [0 to 4] compared with 1 [0 to 3] in group 1, P<0·001). However, VAS scores were not statistically different between groups (group 1: mean 39·4 mm [s.d. 24·0)]; group 2: 30·1 mm [25·9]; P=0·303).
C linical S ignificance : Addition of N₂O to isoflurane anaesthesia results in a lower incidence of adverse behaviour (for example restlessness) and marginally faster recovery.     

Dual Chamber Pacemaker Implantation in Dogs with Atrioventricular Block

Background: Pacemaker implantation is the treatment of choice for symptomatic bradyarrhythmias. In dogs, a single chamber system is commonly used. In human patients with high-grade 2nd- or 3rd-degree atrioventricular (AV) block, physiologic pacing is recommended, because it improves cardiac output, blood pressure, exercise tolerance, and quality of life. In dogs, this type of pacing is seldom used.
Hypothesis: The implantation of a dual chamber pacemaker in dogs with AV block is a feasible procedure for restoring AV synchrony.
Animals: Thirty-three privately owned dogs with high-grade 2nd- or 3rd-degree AV block were included.
Methods: Patient data of all dogs with AV block presented for pacemaker implantation between December 1997 and November 2004 were reviewed.
Results: Dual chamber pacemaker implantation with AV synchronous stimulation was successfully performed in 33/33 dogs (100%). In 9/33 (27%) major and in 12/33 (36%) minor complications were observed. Mean survival time for the patients discharged from hospital (n = 32) was 33.6 ± 20.4 months (range, 3.9–83.5 months).
Conclusion and Clinical Importance: Dual chamber pacing is a feasible procedure in dogs with 2nd- or 3rd-degree AV block and is not associated with a higher complication rate compared with single chamber pacemaker systems. A major advantage over ventricular demand pacemaker systems is the restoration of AV synchrony for a substantial period of time.     

Outcome following removal of canine spindle cell tumours in first opinion practice: 104 cases

O bjectives : To define the outcome of a cohort of canine patients with a histological diagnosis of spindle cell tumour of soft tissue managed solely by surgery in first opinion practice.
M ethods : Clinical details of 104 spindle cell sarcomas submitted to Finn Pathologists during the year 2000 were reviewed. Questionnaires were sent to the submitting veterinarians, requesting details about the tumour, surgery performed and ultimate outcome of the patient.
R esults : The method of surgical resection was described as marginal in 45 dogs (44·2 per cent). Excision margins of 3 cm or more were described in less than 10 per cent of cases. Tumours recurred locally in 29 dogs (27·9 per cent). Eighteen dogs (21·7 per cent) died of tumour-related causes. Most deaths were unrelated to sarcoma (50 dogs, 60·2 per cent) or unknown (15 dogs, 18 per cent). The median survival time was 1013 days. Tumour size, location or degree of surgical resection were not significantly related to survival or tumour recurrence. A palpable assessment of tumour invasion into underlying tissues was significantly associated with decreased disease-free interval (P<0·0001) and survival time (P = 0·0070).
C linical S ignificance : The results of this retrospective study indicate that many spindle cell tumours managed in first opinion practice exhibit a low-grade biological behaviour and may respond well to more conservative surgery than current recommendations advise.     

Therapeutic efficacy of topical hydrocortisone aceponate in experimental flea-allergy dermatitis in dogs

Objective   To evaluate the treatment efficacy of a topical spray containing hydrocortisone aceponate (HCA) on dogs with flea-allergy dermatitis (FAD).
Design   A controlled clinical study was conducted on dogs with experimentally induced FAD. Sixteen laboratory beagles with mild to moderate clinical signs were divided into two groups. The test group received HCA by topical spray once daily for 7 days, while the control group did not. Pruritic events (time and frequency) were videotaped and then scored. Clinical signs (erythema, papules, excoriation and alopecia) present on four anatomical regions were monitored and their severity directly assessed.
Results   After 2 days, pruritus was reduced by 94% in the treatment group and by 24% in the control group (P = 0.014) in cumulative time, and by 86% versus 34% (P = 0.034) in frequency. The HCA spray also resulted in significant improvements in overall clinical signs: 23% versus 0% in the control group (P = 0.0006) on day 3 and 43% versus 15% in the control group (P = 0.0006) on day 7. During the 7-day trial, no drug-related adverse effects were observed.
Conclusions   Topical treatment with HCA showed a rapid and potent antipruritic effect on dogs with FAD. HCA also demonstrated significant overall therapeutic effects on FAD-associated skin lesions.     

Dietary Management of Hepatic Copper Accumulation in Labrador Retrievers

Background: Copper-associated chronic hepatitis (CACH) recently has been recognized in the Labrador Retriever as an inherited disorder with a late onset of clinical signs. No studies have investigated dietary management for the long-term treatment of this disease or for its potential in delaying the onset of clinical signs in subclinical cases.
Objectives: To investigate the effects of a low-copper diet and zinc gluconate on hepatic copper concentrations in Labrador Retrievers with abnormal hepatic copper concentrations.
Animals: Twenty-four client-owned Labradors that were related to patients affected with CACH and that had been diagnosed with increased hepatic copper concentrations.
Methods: Hepatic copper concentrations were assessed before and after an average of 8 and 16 months of treatment. During this time, all dogs were fed exclusively a low-copper diet. In addition, dogs were assigned to 1 of 2 groups in a randomized double-blind manner to receive a supplement of zinc gluconate or placebo.
Results: Twenty-one dogs completed the study. Hepatic copper concentrations decreased in both groups at recheck 1 (n = 21; group 1, P < .001; group 2, P = .001) and at recheck 2 (n= 16; group 1, P = .03; group 2, P = .04). No difference in hepatic copper concentrations was found between the 2 groups before treatment ( P = .65), at recheck 1 or at recheck 2 ( P = .52–.79).
Conclusions and Clinical Relevance: Feeding low-copper diets to Labradors is effective in decreasing hepatic copper concentrations. Adjunctive treatment with zinc does not appear to increase the copper-lowering effects of dietary management.     

Lack of Evidence of Pregnancy-Induced Alloantibodies in Dogs

Background: It is controversial whether or not pregnant bitches become sensitized to red blood cell (RBC) antigens.
Hypothesis: Bitches do not develop alloantibodies to RBC antigens during gestation and can be used safely as blood donors.
Animals: The study group included 35 healthy female dogs with a prior history of 1 (n = 12), 2 (n = 14), or ≥ 3 (n = 9) pregnancies. The control group consisted of 15 healthy female dogs without any history of pregnancy.
Methods: All dogs were blood typed for dog erythrocyte antigens (DEA) 1.1, 1.2, 3, 4, 5, and 7 using ethylenediaminetetraacetic acid blood samples and polyclonal antisera. Antibody screening was performed with serum and canine RBC panels of known blood type. An autocontrol and direct antiglobulin test were performed to rule out the presence of autoantibodies.
Results: The only alloantibodies identified were those against DEA 7 and the prevalence of anti-DEA 7 alloantibodies was similar in dogs with known history of pregnancy (11.4%) and in the control group (13.3%).
Conclusions and Clinical Importance: These results confirm previous studies and clinical transfusion medicine experience. Naturally occurring anti-DEA 7 alloantibodies have been reported but their clinical relevance has not been shown. Pregnancy does not appear to sensitize dogs to RBC antigens. Consequently, dogs with prior history of pregnancy can be used safely as blood donors. Conversely, no additional pretransfusion compatibility studies would be required should these dogs themselves need to be transfused.     

Efficacy of leflunomide for treatment of refractory inflammatory colorectal polyps in 15 Miniature Dachshunds

Inflammatory colorectal polyp (ICRP), common in miniature dachshunds, presents with hematochezia, tenesmus and mucoid feces. Although an 80% response rate has been reported when treated with prednisolone and cyclosporine, effective treatment is needed for the remaining 20% of ICRP dogs. Leflunomide is an immunosuppressive drug reported as effective in several immune-mediated diseases. In the present study, we retrospectively evaluated the efficacy and adverse effects of leflunomide in 15 ICRP dogs that were refractory to treatment with prednisolone and cyclosporine. Treatment efficacy was assessed by endoscopy, clinical symptoms and rectal palpation. Adverse effects were determined by clinical symptoms and blood testing during follow-up. The leflunomide treatment response rate was 93.3%. The median dosage of leflunomide and the median response time were 3 mg/kg (range: 1.7–4.0 mg/kg) and 35 days (range: 20–119 days), respectively. Adverse effects observed included lethargy (3 dogs), anorexia (1 dog), respiratory symptoms (1 dog), leukocytopenia (2 dogs), thrombocytopenia (1 dog), anemia (1 dog) and liver enzyme elevation (8 dogs). Most of the adverse effects improved with symptomatic treatment and leflunomide discontinuation or dosage reduction. In conclusion, leflunomide treatment is effective in ICRP dogs refractory to treatment with prednisolone and cyclosporine. Because several adverse effects were observed, close monitoring is needed during leflunomide treatment follow-up.     

A phase II clinical trial of vinorelbine in dogs with cutaneous mast cell tumors

Background: Few effective drugs are available to treat dogs with locally aggressive or metastatic mast cell disease.
Hypothesis: Vinorelbine, a semisynthetic derivative of vinblastine, is an effective drug for the treatment of canine mast cell tumors (MCT).
Animals: Twenty-four dogs with cutaneous MCT.
Methods: Dogs with at least 1 measurable, cytologically confirmed, and previously untreated cutaneous MCT received a single treatment with vinorelbine at the previously established dosage of 15 mg/m² IV. Tumor measurements and CBC were evaluated before and 7 days after treatment. Adverse events were graded according to Veterinary Cooperative Oncology Group (VCOG) guidelines.
Statistics: Data were accrued in accordance with a Simon's 2-stage design with a noninteresting response rate of .05, a target response of .25, and α and β values of .10.
Results: Three of 24 dogs (13%) had a response to treatment, including 1 measurable complete response and 1 measurable partial response. The 3rd dog had microscopic complete response to treatment with stable measurable disease. Twenty other dogs (83%) had stable disease and 1 dog (4%) had progressive disease. Neutropenia occurred in 13 dogs (54%) (grade 1, n = 4; grade 3, n = 6; grade 4, n = 3). Gastrointestinal toxicity occurred in 11 dogs (46%) (anorexia: grade 1, n = 3; grade 2, n = 1; grade 3, n = 1; diarrhea: grade 1, n = 2; grade 3, n = 1; vomiting: grade 1, n = 5; grade 3, n = 1).
Conclusions and Clinical Importance: Vinorelbine was associated with an overall response rate of 13% and a high prevalence of neutropenia. Additional studies are indicated to determine if repeated dosing of vinorelbine or combination of vinorelbine with other drugs increases the observed biologic activity against canine MCT.     

The effect of omeprazole on oesophageal pH in dogs during anaesthesia

O bjectives : Intra-operative, gastro-oesophageal reflux may be associated with post-anaesthestic complications such as oesophagitis and oesophageal stricture in dogs. The aim of this study was to investigate the effect of preoperative administration of omeprazole, a proton pump inhibitor, on oesophageal pH in anaesthetised dogs.
M ethods : Forty-seven dogs undergoing elective pelvic limb orthopaedic surgery were enrolled into the study. These were randomly allocated to treatment group (n=22) or control group (n=25). The treatment group received one dose of omeprazole (1 mg/kg po) at least 4 h before anaesthesia. All dogs were anaesthetised by the same standardised protocol. A pH probe was inserted into the distal oesophagus after induction of anaesthesia and oesophageal pH was continuously monitored.
R esults : In the treatment group, four animals (18 per cent) showed a sudden decrease in oesophageal pH (<4). In the control group the same phenomenon was detected in 13 animals (52 per cent). Gastro-oesophageal reflux occurred more frequently in the control group compared with the omeprazole group (odds ratio 4·7, 95 per cent C.I. 1.1 to 24.7, P=0.032).
C linical S ignificance : This study suggests that the preoperative administration of omeprazole is effective in reducing the incidence of gastro-oesophageal reflux during anaesthesia in dogs.     

Canine spinal nephroblastoma: long-term outcomes associated with treatment of 10 cases (1996-2009)

Objective: To report clinical outcome associated with treatment of canine spinal cord nephroblastoma (CSN). Study Design: Case series. Animals: Dogs (n=10) with histopathologically confirmed CSN. Methods: Records of dogs with CSN were reviewed and clinicopathologic, diagnostic imaging, treatment, outcome, and survival data were collected. Results: CSN resulted in clinical signs of chronic, progressive T3–L3 myelopathy in young, large breed dogs, with an overrepresentation of German Shepherd Dogs (n=4). All CSN were located between T9 and L2. Dogs treated with cytoreductive surgery (n=6) or radiotherapy (1) survived longer (median, 374 days; range, 226–560 days) than dogs treated palliatively (3; median, 55 days; range, 38–176 days). Tumors confined to an intradural–extramedullary (ID–EM) location were associated with superior survival (n=6; median, 380 days; range, 176–560 days) than tumors with intramedullary (IM) involvement (n=4; median, 140 days; range, 38–269 days). Treatment resulted in temporary improvement in neurologic function in 9 dogs, including all dogs treated surgically, but local disease progression resulted in death of 8 dogs. Conclusions: Results of this observational study suggest that surgical cytoreduction and radiotherapy are effective at improving survival in dogs with CSN, and that ID–EM tumors may be associated with a more favorable prognosis than IM neoplasms.     

The Effect of Hetastarch (670/0.75) on Urine Specific Gravity and Osmolality in the Dog

Background: Urine specific gravity (USG) is used clinically to estimate urine osmolality (UOsm). Although USG has been shown to have a linear correlation with UOsm in dogs, the relationship is altered when there are significant numbers of high molecular weight (MW) molecules in the urine.
Hypothesis: USG would no longer predict UOsm in dogs given intravenous hetastarch (670/0.75)(HES).
Animals: Eight healthy employee-owned adult dogs.
Methods: Prospective, controlled experimental study. USG and UOsm were measured every 30 minutes from t=0 minutes to t=360 minutes. Dogs were administered 20mL/kg of either NaCl 0.9% (control group, n=4) or HES (treatment group, n=8) IV over 1 hour starting at t=90 minutes.
Results: There was a decrease in UOsm in both groups starting at t=120 minutes and continuing for the study duration, and there was no significant difference in UOsm between treatment and control groups across all time points. There was an appropriate decrease in USG from t=120 minutes for the control group. In the treatment group, USG increased significantly at t=120 minutes ( P = .0006), t=150 minutes ( P = .0002), and t=180 minutes ( P = .0044). The largest increase in USG occurred at t=150 minutes with a mean USG of 1.070 ± 0.021 (range 1.038-1.104).
Conclusions and clinical importance: Urine specific gravity should not be used to estimate urine solute concentration in dogs following the administration of 20mL/kg of HES. In a clinical setting, the evaluation of USG following this dose of HES may lead to an overestimation of urine concentration.     

Survival in Dogs with Nasal Adenocarcinoma: 64 Cases (1981–1995)

Case records of 64 dogs with nasal adenocarcinoma were reviewed. The effects of age, gender, tumor stage, presence of metastatic lesions, and treatment method on survival time were examined. Surgery groups included rhinotomy (n = 9), transnasal curettage (n = 29), and no surgery (n = 26). Chemotherapy groups included fluorouracil-cyclophosphamide combination therapy (n = 15), mitoxantrone (n = 7), and no chemotherapy (n = 42). Fifty-three dogs received fractionated cobalt 60 radiation therapy. Surgical procedure, chemotherapy group, and stage of primary tumor were not significantly associated with survival time ( P > .05). Dogs that received radiation therapy had a significantly longer median survival time (424 days) than dogs that did not (126 days) ( P = .0001). The presence of either regional lymph node or pulmonary metastasis was associated with significantly shorter median survival time (109 days) when compared to dogs without metastases (393 days) ( P = .0125). When only dogs that had received radiation therapy were considered, neither surgical treatment nor chemotherapy group was associated with significant changes in median survival time. An alternate staging system emphasizing the presence or absence of metastases is proposed. Key words: Chemotherapy; Metastasis; Radiotherapy.     

The effect of Hetastarch (670/0.75) in vivo on platelet closure time in the dog

Objective – To evaluate the effect of 6% hydroxyethyl starch (HES) solution in vivo, with an average molecular weight of 670 kDa and degree of substitution of 0.75, on canine platelet function.
Design – Prospective, controlled-experimental study.
Setting – University of California, Davis, Veterinary Medical Teaching Hospital.
Animals – Seven healthy employee-owned dogs.
Interventions – Seven dogs were included in the treatment group. Four of these dogs also served as the control group. Platelet closure time (CT) was measured using a platelet function analyzer and collagen/ADP cartridges. Dogs were given 20 mL/kg of either sodium chloride 0.9% (control group, n =4) or HES (treatment group, n =7) IV over 1 hour. CT was measured before the infusion, and at 1, 3, 5, and 24 hours after the start of the infusion.
Measurements and Main Results – There was a significant change over time from 0 to 24 hours ( P <0.001), a significant difference between groups across time ( P <0.001), and a significant group-by-time interaction ( P =0.007). At 3 hours, mean CT for the treatment group was 122.3±18.1 seconds, which was significantly different ( P <0.001) from the control group (71.0±3.5 s). At 5 hours, mean CT for the treatment group was 142.7±33.9 seconds, which was significantly different ( P =0.001) from the control group (75.0±8.6 s). Mean CT at 24 hours was within the reference interval for both the control and treatment group (66.0±2.9 and 81.8±11.9 s, respectively); however, CT in 3 individual dogs in the treatment group at this time point remained prolonged.
Conclusions – A clinically relevant dose of HES 670/0.75 prolongs CT in dogs for up to 24 hours. This may be due to platelet dysfunction in addition to the effects of hemodilution, and therefore, may increase the risk of bleeding.     

Surgical Treatment of Mineralized and Nonmineralized Supraspinatus Tendinopathy in Twenty-four Dogs

Objective— To report and compare the clinical diagnosis, surgical treatment, histopathologic changes, and outcomes of dogs with mineralized and nonmineralized supraspinatus tendinopathy (ST).
Study Design— Case series.
Animals— Dogs (n=24) with ST.
Methods— Medical records (1995–2006) of dogs with ST that had surgical treatment were reviewed. Results of clinical examination, diagnostic imaging, surgery, histopathology of resected tendon tissue, and outcome were compared between dogs with mineralized and nonmineralized ST.
Results— There were 15 dogs with mineralized ST and 9 with nonmineralized ST. Chronic, unilateral, intermittent or waxing-waning lameness, and pain elicited on palpation of the cranial aspect of the shoulder were the most consistent findings. On ultrasonographic or magnetic resonance imaging (MRI) of 35 shoulders, enlargement of the supraspinatus tendon (54%), increased fluid content (63%), and medial displacement of the biceps tendon (60%) were observed. Eleven of 12 dogs with bilateral abnormalities only had unilateral lameness. Surgery was performed in 30 shoulders. Resected tendon specimens had myxomatous degeneration and/or cartilaginous metaplasia in 11 of 13 dogs in the mineralized group and all 9 dogs in the nonmineralized group. Functional outcome after surgery was poor in 3 dogs and good-to-excellent in 16.
Conclusions— Mineralized and nonmineralized ST have many similarities. Although lameness is usually unilateral, the supraspinatus tendon may be affected bilaterally.
Clinical Relevance— Ultrasonography and MRI are good imaging techniques for detection of ST especially the nonmineralized form. Surgical treatment results in good recovery of limb function. Nonmineralized ST is a recently described disorder in dogs and evaluation of more cases is necessary to determine outcome after surgical or medical treatment.     

A prospective study of clopidogrel therapy in dogs with primary immune-mediated hemolytic anemia

Background: A major cause of death in dogs with primary immune‐mediated hemolytic anemia (pIMHA) is thrombotic disease. Ultralow‐dose aspirin (ULDA) is commonly used to prevent thrombosis in dogs with pIMHA; however, the efficacy of antiplatelet agents in dogs with pIMHA is unknown. Hypothesis: The use of clopidogrel (CL), alone or in combination with ULDA, would improve survival to discharge and at 90 days without important adverse effects compared with ULDA alone in dogs with pIMHA treated with standard immunosuppressive therapy. Animals: Twenty‐four client‐owned dogs with pIMHA. Methods: Prospective, positive‐controlled, unmasked clinical trial with dogs randomized in 3 treatment groups to receive PO ULDA or CL or both. Results: There was no identifiable adverse reaction, evidence of hemorrhage, or increase in transfusion requirements associated with CL therapy, either alone or combined with ULDA, compared with ULDA alone. There was no significant difference between treatment groups with respect to survival to discharge and at 90 days. Conclusions and Clinical Importance: This study suggests that CL therapy, alone or in combination with ULDA, was safe and had similar short‐term survival compared with ULDA alone in a small group of dogs with pIMHA able to tolerate oral medications and treated with standard immunosuppressive treatment.