Immune-mediated polyarthritis and anterior uveitis secondary to zonisamide administration in a dog with refractory epilepsy.

The objective of this article is to describe a case of suspected zonisamide-induced immune-mediated polyarthritis (IMPA) and anterior uveitis in a dog. A 7-year-old male neutered Siberian Husky with a history of refractory idiopathic epilepsy was presented for cluster seizures. Following the addition of zonisamide to the antiepileptic regime, the dog developed new IMPA and anterior uveitis. Within a few weeks of discontinuation of the zonisamide, the dog's IMPA and anterior uveitis resolved. These immune-mediated conditions were thus presumed to be an idiosyncratic reaction to zonisamide. To our knowledge, this is the first report of IMPA and anterior uveitis in dogs associated with zonisamide administration at its recommended dose.

Acute kidney injury from presumptive intramural ureteral hemorrhage secondary to diphacinone rodenticide exposure in a dog.

OBJECTIVE: To describe the clinical features and outcome of a dog with anticoagulant rodenticide (diphacinone) exposure, which was subsequently diagnosed with a coagulopathy characterized by hemoperitoneum, and presumptive ureteral wall hemorrhage contributing to acute kidney injury (AKI). CASE SUMMARY: A 4-year-old, female neutered Australian Cattle Dog was evaluated for an acute onset of lethargy, decreased appetite, and a mild right thoracic limb lameness. Radiographs and point of care ultrasound demonstrated retroperitoneal and peritoneal effusion. Diagnostic abdominocentesis confirmed hemorrhagic effusion. Complete blood count, biochemistry, and coagulation profile showed a regenerative anemia (PCV 32%), thrombocytopenia (platelets 96 × 109 /L [96 × 103 /µl]), azotemia (BUN 38.9 mmol/L [109 mg/dl], creatinine 512.8 µmol/L [5.8 mg/dl]), and coagulopathy (prothrombin time >100 s, activated partial thromboplastin time >42.3 s). The client reported access to anticoagulant rodenticide up to 72 hours prior to presentation. Ultrasonographic examination revealed bilateral pyelectasia and hydroureter with thickened distal ureteral walls at the level of the ureteral-vesicular junctions. The ultrasonographic conclusion was presumptive intramural ureteral hemorrhage resulting in ureteral obstruction. The patient was diagnosed with AKI with likely prerenal, renal, and postrenal components. Treatment included vitamin K and frozen plasma transfusion. The patient recovered fully and was discharged 3 days after presentation. Two days after discharge, the patient had improvement in azotemia (BUN 10.7 mmol/L [30 mg/dl], creatinine 176.6 µmol/L [2.0 mg/dl]). Gas chromatography-mass spectrometry confirmed presence of diphacinone in the blood. Repeat ultrasound and biochemistry 60 and 210 days, respectively, after discharge showed resolution of ureteral wall thickening, hydroureter, pyelectasia, and recovery of kidney parameters. NEW OR UNIQUE INFORMATION: Although nephropathies secondary to anticoagulant therapy have been described in people, the authors believe this is the first report of diphacinone anticoagulant rodenticide exposure contributing to an AKI secondary to obstruction from ureteral wall hemorrhage in the veterinary literature.

A case of epiglottic entrapment in a cat.

OBJECTIVE: The objective of this study was to describe a case of epiglottic entrapment in a cat. CASE SUMMARY: A 5-month-old male neutered Russian Blue cat was evaluated for progressive stertorous upper airway sounds, acute onset vestibulopathy and abnormal laryngeal anatomy. Endotracheal intubation was only able to be achieved using videoscopic guidance and identified concern for severe nasopharyngeal stenosis. A computerized tomography scan revealed otitis interna, narrowed nasopharynx and no definitive cause for the stertorous breathing. The cat recovered very slowly from anaesthesia due to concern for airway obstruction following extubation. It was discharged the following day and then passed away at home 2 weeks later. Necropsy revealed that the epiglottis was obscured by 2 cm of redundant mucosal tissue extending from the base of the tongue to the larynx resulting in epiglottic entrapment. Also noted was chronic, severe otitis interna and externa. Upper airway obstruction is suspected to be the cause of sudden death. NEW OR UNIQUE INFORMATION: To the authors' knowledge, this is the first report of these oropharyngeal anatomic abnormalities in a cat.

5-Hydroxytryptophan toxicity successfully treated by haemodialysis in a dog.

OBJECTIVE: To describe a case of 5-hydroxytryptophan (5-HTP) toxicity successfully treated with haemodialysis in a dog. CASE SUMMARY: A 3-year-old, male neutered Labrador Retriever, weighing 28.2 kg, presented to the emergency department approximately 4-5 h after ingesting a human supplement containing 200 mg of 5-HTP. The amount of 5-HTP ingested was estimated between 980 and 1988 mg (35-71 mg/kg). At presentation, the dog demonstrated progressive neurologic abnormalities consistent with serotonin syndrome, including altered mentation and ataxia. Due to the magnitude of the ingested dose and progression of clinical signs, extracorporeal blood purification with intermittent haemodialysis was chosen to expedite clearance of 5-HTP. High-efficiency haemodialysis was initiated, and the dog showed continued clinical improvement throughout the 5-h treatment. Clinical signs resolved completely within 12 h. Sequential blood and urine samples were obtained to document levels of both 5-HTP and serotonin. The dog was discharged 24 h after presentation with complete resolution of clinical signs. NEW OR UNIQUE INFORMATION: This is the first report documenting the serial changes in 5-HTP concentrations during treatment with haemodialysis.

Successful treatment of 5-fluorouracil toxicosis with hemodialysis.

OBJECTIVE: To describe the successful treatment of lethal dose 5-fluorouracil (5-FU) toxicosis using hemodialysis. CASE SUMMARY: A 4-month-old intact female Golden Retriever was presented to the emergency department after ingesting 20 g of 5% 5-FU cream. The puppy developed refractory seizures and became comatose with uncontrolled tonic-clonic convulsions. Because of the low molecular weight and minimal protein binding of 5-FU, a single hemodialysis treatment was employed for detoxification. The puppy improved clinically posttreatment and was successfully discharged 3 days after admission. Postingestion leukopenia and neutropenia occurred but were responsive to treatment with filgrastim. The puppy is neurologically normal and has no lasting effects 1 year postingestion. NEW OR UNIQUE INFORMATION PROVIDED: To the authors' knowledge, this is the first reported case in veterinary medicine of a potentially fatal 5-FU ingestion that has been treated with intermittent hemodialysis.

Effects of storage and leukocyte reduction on the concentration and procoagulant activity of extracellular vesicles in canine packed red cells.

OBJECTIVES: To characterize the size and procoagulant activity of extracellular vesicles (EV) that accumulate in canine packed red blood cells (pRBCs) over time and the effect of leukocyte reduction on these characteristics. DESIGN: Prospective cohort study. SETTING: Private small animal specialty referral hospital and university research laboratories. ANIMALS: Ten healthy blood donor dogs. INTERVENTIONS: Five pRBCs units were obtained according to standard protocols, and 5 were leukocyte-reduced prior to processing. Platelet-free supernatant from the pRBC units was collected on days 0, 10, 20, 32, and 42. MEASUREMENTS AND MAIN RESULTS: Nanoparticle tracking analysis was performed to determine the size and concentration of EVs. Thrombin generation associated with phosphatidylserine-positive EVs was determined using a capture assay. Factor Xa generation associated with phosphatidylserine-positive EVs and tissue factor-positive EVs was measured in a subset of EVs isolated by centrifugation of the supernatant at 20,000 × g. R package nparLD and the Mann-Whitney U-test were used to determine the effect of duration of storage and the effect of leukocyte reduction, respectively. Small (mean < 125 nm) procoagulant EVs accumulated over time, with significant increases occurring on or after day 20 in both non-leukocyte reduced and leukocyte-reduced units. The procoagulant activity of the EVs was due to phosphatidylserine, not tissue factor. Increases in EV concentration and procoagulant activity occurred earlier in non-leukocyte reduced units. Extracellular vesicle accumulation and procoagulant activity were not decreased at any individual time point by leukocyte reduction. CONCLUSIONS: Further studies characterizing and determining the clinical relevance of small procoagulant EVs in pRBCs are warranted.

Pharmacokinetics and efficacy of trazodone following rectal administration of a single dose to healthy dogs.

OBJECTIVE: To determine the pharmacokinetics and efficacy of trazodone following rectal administration of a single dose to healthy dogs. ANIMALS: 6 healthy adult dogs. PROCEDURES: Each dog received a single dose of trazodone (approx 8 mg/kg) per rectum. Trazodone tablets were crushed into a powder, mixed with 5 mL of tap water, and injected into the rectum via a red rubber catheter. Sedation scores were assigned, and blood samples were collected for determination of plasma trazodone concentration at predetermined times before and after drug administration. Pharmacokinetic parameters were estimated by noncompartmental analysis. RESULTS: Plasma trazodone concentration remained below the detection limit for 1 dog even though it became moderately sedate. Median (interquartile [25th to 75th percentile] range [IQR]) maximum plasma trazodone concentration and volume of distribution and clearance corrected for bioavailability were 1.00 µg/mL (0.66 to 1.40 µg/mL), 10.3 L/kg (7.37 to 14.4 L/kg), and 639 mL/kg/h (594 to 719 mL/kg/h), respectively. Median time to maximum plasma trazodone concentration and elimination half-life were 15 minutes (range, 15 to 30 minutes) and 12 hours (IQR, 7.99 to 12.7 hours), respectively. All dogs became mildly or moderately sedate, and the extent of sedation was maximal at a median of 30 minutes (IQR, 30 to 60 minutes) after trazodone administration. No adverse effects were observed. CONCLUSIONS AND CLINICAL RELEVANCE: Rectal administration of trazodone may be a viable option for sedation and treatment of anxiety in dogs for which administration of sedatives and anxiolytics by other routes is contraindicated. Further research is necessary to better elucidate the pharmacokinetics and efficacy of trazodone following rectal administration and determine optimal dosing.

Suspected Acute Respiratory Distress Syndrome Associated With the Use of Intravenous Lipid Emulsion Therapy in a Dog: A Case Report.

A 12-year-old male neutered Bichon Frise presented to the Emergency Department for stupor and bradycardia after ingestion of chocolate covered 450 mg (90 mg/kg) tetrahydrocannabinol. The patient was hospitalized for supportive care, IV fluid therapy and monitoring in the intensive care unit. During hospitalization the patient became comatose and bradypneic. Treatment with intravenous lipid emulsion (ILE) therapy was instituted to accelerate toxin elimination, reduce the risk of complications related to progressive obtundation and shorten hospitalization time. Five hours after infusion, the patient developed severe respiratory distress and was ultimately euthanized. Post-mortem histologic evaluation of lung revealed severe pulmonary edema consistent with acute respiratory distress syndrome. There are infrequent reports of adverse effects associated with ILE therapy for toxicosis in veterinary medicine despite reports of complications such as acute respiratory distress syndrome in human literature. The purpose of this report is to describe the potential for a severe adverse event after treatment of a toxicosis with ILE therapy.

Presumptive intraperitoneal envenomation resulting in hemoperitoneum and acute abdominal pain in a dog.

OBJECTIVE: To describe the clinical features, diagnostic findings, treatment, and outcome of a dog with acute abdominal pain and hemoperitoneum secondary to a presumptive intraperitoneal (IP) snakebite. CASE SUMMARY: A 10-month-old castrated male mixed-breed dog was evaluated for suspected snake envenomation. The dog presented recumbent and tachycardic with signs of severe abdominal pain. Two cutaneous puncture wounds and hemoperitoneum were discovered during evaluation. Ultrasonographic examination revealed communication of the wounds with the peritoneal cavity. The dog was treated with supportive care, parenteral analgesia, packed red blood cell and fresh frozen plasma transfusions, crotalid antivenom, and placement of an IP catheter to provide local analgesia. The dog recovered fully and was discharged 5 days after initial presentation. NEW OR UNIQUE INFORMATION PROVIDED: To our knowledge, this is the first report of IP envenomation accompanied by hemorrhage treated with continuous IP analgesia in the veterinary literature.

Evaluation of a point-of-care anticoagulant rodenticide test for dogs.

OBJECTIVE: To evaluate a point-of-care anticoagulant rodenticide lateral flow analyzer for the detection of various rodenticide compounds. DESIGN: Prospective, laboratory study. SETTING: University teaching hospital. ANIMALS: The study utilized a serum sample from one healthy canine donor. Samples were centrifuged and serum samples were aliquoted and either used within 4 hours or frozen at -70°C for further quantitative analysis. INTERVENTIONS: Samples were spiked with clinically relevant concentrations of 1 of 6 rodenticide compounds (warfarin, pindone, chlorphacinone, brodifacoum, bromethalin, and its metabolite desmethylbromethalin). Seventy-five microliters of spiked serum (or unaltered serum) was introduced into the lateral flow test. MEASUREMENTS AND MAIN RESULTS: Three readers who were blinded to the sample preparation interpreted the lateral flow test as either positive or negative for the presence of anticoagulant rodenticide. All readers were in agreement for the results of each serum sample. The point-of-care test kit was able to detect a single anticoagulant rodenticide (warfarin) at concentrations below the manufacturer's recommended limit of detection, but was unable to detect any other anticoagulant rodenticide. CONCLUSIONS: The results of this test and therapeutic interventions must be considered in light of history, physical examination, and other clinical data. Based on results from this study, the test kit only detects warfarin and not other more common second-generation anticoagulant rodenticides.

Systematic evaluation of evidence on veterinary viscoelastic testing part 4: Definitions and data reporting.

OBJECTIVE: To systematically examine evidence surrounding definitions and reporting of data for viscoelastic testing in veterinary medicine. DESIGN: Standardized, systematic evaluation of the literature, categorization of relevant articles according to level of evidence and quality, and development of consensus on conclusions for application of the concepts to clinical practice. SETTING: Academic and referral veterinary medical centers. RESULTS: Databases searched included Medline, CAB abstracts, and Google Scholar. CONCLUSIONS: All 4 standard thromboelastography (TEG) and rotational thromboelastometry (ROTEM) variables should be universally reported, and the reporting of shear elastic modulus in addition to maximum amplitude (MA) is encouraged. There is insufficient evidence to support universal usage of the coagulation index at this time. The K value and clot formation time are the most variable of the 4 parameters, with alpha angle, MA, and maximum clot firmness generally the least variable. Individual studies should report sufficient data on patients and institutional controls to enable definitions of hypo- and hypercoagulability to be evaluated post-hoc, and it is recommended that all studies specifically report how these conditions were defined. In reporting data relating to fibrinolysis, the TEG variables LY30, LY60, CL30, CL60, and the ROTEM variables LI30, LI60, ML, LOT, and LT should be documented. Studies should report sufficient data on patients and controls to enable definitions of hyper- and hypofibrinolysis to be evaluated post-hoc, and we suggest that standard TEG/ROTEM assays may be unable to detect hypofibrinolysis in companion animals. We recommend that every center establish reference intervals, which are specific to either TEG or ROTEM. These reference intervals should be established using veterinary clinical pathology guidelines, standardized protocols, and a minimum of 40 healthy animals. There are currently insufficient data in companion animals to suggest a utility for Vcurve variables beyond that of standard TEG variables.