Clinical examination findings and electrolyte abnormalities of dogs with marijuana/tetrahydrocannabinol toxicity: 223 cases (January 2017-July 2021).

OBJECTIVE: The goal of this study was to describe the historical, physical, neurologic, and clinicopathologic findings in dogs with a definitive diagnosis of marijuana/tetrahydrocannabinol toxicity. ANIMALS: A total of 223 dogs with known ingestion of marijuana or a positive tetrahydrocannabinol result on human urine multidrug test. METHODS: Retrospective study from January 2017 to July 2021. RESULTS: Median age was 1 year (1 month to 12 years). A common history was becoming acutely neurologic after going outside or to a public place (62/223 [27.8%]). Most owners denied possibility of exposure (152/223 [68%]). Median vitals were normal, but hyperthermia (38/212 [22.6%]), tachycardia (82/222 [37%]), and systemic hypertension (37/61 [60.7%]) were common abnormalities. The most common clinical signs included ataxia (197/223 [88.3%]), hyperesthesia (168/223 [75.3%]), urinary incontinence (102/223 [45.7%]), lethargy (140/223 [62.5%]), and vomiting (58/223 [26%]). The most common combinations of neurologic signs included ataxia and hyperesthesia (157/223 [70.4%]) and ataxia, hyperesthesia, and urinary incontinence (81/223 [36.3%]). Mild hyperkalemia (39/76 [51.3%]) and mild hypercalcemia (53/67 [79.1%]) were common. Twenty-two dogs were hospitalized. Survival was 100%. CLINICAL RELEVANCE: A common presentation for marijuana toxicosis included young dogs with acute ataxia and hyperesthesia, with and without urinary incontinence, after going outside or to a public place. Vitals were often normal, but hyperthermia, tachycardia, and hypertension were common. Bloodwork was mostly normal, but mild hyperkalemia and mild ionized hypercalcemia were common. Marijuana should be high on the differential list with these history, physical examination, neurologic, and electrolyte abnormalities, regardless of owner denial or negative human urine multidrug test.

Pulmonary hypertension is associated with hypocoagulability in dogs: a retrospective analysis of 66 cases (2013-2021).

OBJECTIVE: To describe coagulation profiles in dogs with echocardiographic evidence of pulmonary hypertension (PH), to compare them to coagulation profiles in dogs without echocardiographic evidence of PH, and to determine the relationship between coagulation profiles and echocardiographic probability of PH. ANIMALS: 66 dogs with PH (cases) and 86 dogs without PH (controls). METHODS: Retrospective evaluation of records between 2013 and 2021 of dogs that had both an echocardiogram and a coagulation panel performed within 7 days. Dogs that received antithrombotics within 7 days of evaluation and dogs diagnosed with congenital or acquired coagulopathy or other severe systemic disease that could lead to coagulopathy were excluded. Dogs with a low echocardiographic probability of PH were also excluded. The dogs were divided into a PH group and non-PH group based on echocardiographic results. Demographic, clinicopathologic, and traditional coagulation parameters and VCM Vet (Entegrion) parameters were compared between the 2 groups. RESULTS: Dogs with PH were significantly older (median, 11 years vs 9.5 years, P = .02) and had a significantly lower body weight (median, 7.3 kg vs 19.3 kg, P < .001) than controls. Dogs with PH also had a significantly greater percent increase in prothrombin time (PT; P = .02), partial thromboplastin time (PTT; P < .0001), and fibrinogen (P = .045); however, their antithrombin concentration was lower (P = .005) compared to controls. Eight of 65 dogs (12.3%) in the PH group and 1/86 (1.2%) dogs in the non-PH group had an elevation of PT and/or PTT greater than 50% above the reference interval (P = .005). Dogs with PH had 11.9 times (95% CI, 1.5 to 97.9; P = .02) greater odds of being hypocoagulable than dogs without PH based on PT and PTT. CLINICAL RELEVANCE: This study demonstrated an association between a moderate to high echocardiographic probability of PH and a hypocoagulable state in dogs as determined by traditional coagulation assays. It underscores the importance of monitoring the coagulation status in canine patients with PH, particularly before initiating antithrombotic medications.

Retrospective evaluation of the diagnostic utility of computed tomography in dogs with nontraumatic hemoperitoneum: 26 cases (2015-2020).

OBJECTIVE: To describe the appearance of lesions noted on abdominal computed tomography (CT) in dogs with spontaneous hemoperitoneum and determine the utility in using CT to differentiate benign from malignant lesions. DESIGN: Retrospective case series. SETTING: Single-center, university veterinary teaching emergency service. ANIMALS: Twenty-six dogs presented between 2015 and 2020 with spontaneous hemoperitoneum confirmed via abdominocentesis with pre- and postcontrast abdominal CT performed prior to surgery or euthanasia. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: On histopathological diagnosis, 20 of 26 lesions were found to be malignant, and 6 of 26 were benign. Two radiologists reviewed the CTs. Radiologist 1 correctly identified 5 of 6 (83.3%) benign cases and 18 of 20 (90%) malignant cases. Radiologist 2 correctly identified 2 of 6 (33.3%) benign lesions and 18 of 20 (90%) malignant cases. Of the 10 imaging descriptors evaluated, none were significantly associated with the histological diagnosis. CONCLUSIONS: Results from the current study suggest that abdominal CT imaging of spontaneous hemoperitoneum cases is not a reliable indicator of malignancy versus benignancy. As such, prognosis should not be defined using this modality alone prior to emergency surgery and instead should be concluded based on the clinical course of the patient and histopathological findings of the resected tissues after surgery.

The use of impedance aggregometry to evaluate platelet function after the administration of DDAVP in healthy dogs treated with aspirin or clopidogrel.

OBJECTIVE: To evaluate the effect of 1-Desamino-8-d-arginine vasopressin (DDAVP; desmopressin acetate) on platelet aggregation in healthy dogs receiving aspirin or clopidogrel. ANIMALS: 7 healthy staff-owned dogs. PROCEDURES: In this randomized double-blinded crossover study, impedance aggregometry was performed on samples of lithium-heparinized whole blood samples from dogs before (T0) treatment with aspirin (1 mg/kg, PO, q 24 h for 4 days; ASP group) or clopidogrel (1 mg/kg, PO, q 24 h for 4 days; CLP group) and then before (T1) and after (T2) treatment with DDAVP (0.3 µg/kg, IV, once). There was a 14-day washout period before the crossover component. Aggregometry was performed with 4 different assays, each of which involved a different agonist reagent to stimulate platelet function: ADP, thrombin receptor activating peptide-6, arachidonic acid, or collagen type 1. RESULTS: Median results for platelet aggregometry with agonist reagents ADP, arachidonic acid, or thrombin receptor activating peptide-6 significantly decreased between T0 and T1 for the CLP group; however, no meaningful difference in platelet aggregation was detected in the ASP group. Results for platelet aggregometry did not differ substantially between T1 and T2 regardless of treatment group or assay. CONCLUSIONS AND CLINICAL RELEVANCE: Findings suggested that administration of DDAVP may have no effect on platelet aggregation (measured with platelet aggregometry) in healthy dogs treated with clopidogrel. Because no inhibition of platelet aggregation was detected for dogs in the ASP group, no conclusion could be made regarding the effects of DDAVP administered to dogs treated with aspirin.

Clinical relevance of splenic nodules or heterogeneous splenic parenchyma assessed by cytologic evaluation of fine-needle samples in 125 dogs (2011-2015).

BACKGROUND: Splenic nodules and heterogeneous parenchyma are seen frequently in abdominal ultrasound examinations of dogs, but the clinical importance of these lesions remains unclear. OBJECTIVES: To determine whether specific ultrasonographic findings correlate with clinically relevant cytologic diagnoses and determine what sonographic features are correlated with these diagnoses. Another objective was to develop a scoring rubric to help clinicians make decisions on whether or not certain ultasonographic findings of the spleen warrant evaluation by fine-needle cytology. ANIMALS: One-hundred twenty-five adult client-owned dogs with ultrasonographically identified splenic nodules, heterogeneous parenchyma, or both. METHODS: Medical records were retrospectively searched for ultrasound-guided splenic fine-needle cytology reports. Ultrasonographic images were assessed for nodule number, size, echogenicity and distal enhancement, degree of splenic heterogeneity, and peritoneal fluid. Dogs were divided into 2 groups: those with clinically important or clinically irrelevant cytologic findings. Potentially useful and discriminatory ultrasonographic findings were identified by statistical analysis, and the most useful findings were used to generate the scoring rubric. RESULTS: The clinically important group included 25 of 125 dogs (22 malignancies, 3 suppurative inflammation). Splenic nodules 1-2 cm in diameter, peritoneal fluid, and >1 targetoid nodule were associated with clinically important cytologic findings. Receiver operator characteristic analysis showed that the scoring rubric was useful for identifying dogs in the clinically important group. CONCLUSIONS AND CLINICAL IMPORTANCE: Splenic fine-needle cytologic findings identified a clinically relevant diagnosis in 20% of dogs, and larger nodule size, number of targetoid lesions, and presence of peritoneal fluid increase the likelihood of detection of clinically important disease.

Persistent pit viper envenomation in a cat.

CASE SUMMARY: A 4-year-old female spayed, indoor/outdoor domestic mediumhair cat presented with multiple bleeding puncture wounds and hemorrhagic shock. The cat was diagnosed with suspected pit viper envenomation based on the location and appearance of the bite wounds, as well as the presence of severe coagulopathy with prolonged activated coagulation time (762 s), which responded to antivenom administration. The clinical course of the cat was unique owing to the prolonged clinical signs of envenomation that appeared as intermittent coagulopathy and hemorrhage over a 2 week period. Five vials of antivenom were administered and three units of packed red blood cells were transfused over a 7 day period. The cat made a complete recovery with cessation of hemorrhage and normalization of clotting times. RELEVANCE AND NOVEL INFORMATION: This is the first report of persistent pit viper venom-induced coagulopathy in the feline veterinary literature.