Comparison of D-dimer concentration and thromboelastography for diagnosis of cerebrovascular accidents in dogs: A retrospective study.

BACKGROUND: Cerebrovascular accidents (CVAs) in dogs are diagnosed using magnetic resonance imaging (MRI). This modality is sometimes unavailable, and CVAs can resemble other lesions on MRI. D-dimer concentration and thromboelastography (TEG) are utilized in human medicine in addition to diagnostic imaging to support diagnosis of CVAs, but their use in veterinary patients has not been assessed. OBJECTIVE: Assess utility of blood D-dimer concentration and TEG in supporting the imaging diagnosis of CVAs in dogs. ANIMALS: Sixty-eight client-owned dogs with neurologic signs that had brain MRI and D-dimer concentration or TEG performed. METHODS: Multicenter, retrospective study. The incidence of abnormal D-dimer concentration or TEG was compared between patients with MRI evidence of CVA and a control population. Analysis methods included Fisher's exact test or Chi-squared test for association and comparison of independent proportions. RESULTS: Neither D-dimer concentration nor TEG was significantly associated with a CVA (P = .38 and .2, respectively). D-dimer testing was performed in a low-risk population and showed low sensitivity (30.8%; 95% confidence interval [CI], 10%-61%) and high specificity (86.4%; 95% CI, 64%-96%) for CVA diagnosis. Thromboelastography was performed in a high-risk population and showed moderate sensitivity (64.3%; 95% CI, 44%-81%) and specificity (66.7%; 95% CI, 24%-94%) for CVA diagnosis. Abnormal D-dimer concentration or TEG were not helpful in differentiating hemorrhagic from ischemic stroke (P = .43 and .41, respectively). CONCLUSIONS: Although blood D-dimer concentration or TEG alone are not diagnostic of CVAs in dogs, a positive D-dimer result supports additional testing for CVA.

Neurofilament light chain concentration does not correlate with disease status in Labrador Retrievers affected with idiopathic laryngeal paralysis.

OBJECTIVE: The aim of this study was to investigate whether plasma neurofilament light chain (pNfL) concentration was altered in Labrador Retrievers with idiopathic laryngeal paralysis (ILP) compared to a control population. A secondary aim was to investigate relationships between age, height, weight, and body mass index in the populations studied. ANIMALS: 123 dogs: 62 purebred Labrador Retrievers with ILP (ILP Cases) and 61 age-matched healthy medium- to large-breed dogs (Controls). METHODS: Dogs, recruited from August 1, 2016, to March 1, 2022, were categorized as case or control based on a combination of physical exam, neurologic exam, and history. Blood plasma was collected, and pNfL concentration was measured. pNfL concentrations were compared between ILP Cases and Controls. Covariables including age, height, and weight were collected. Relationships between pNfL and covariables were analyzed within and between groups. In dogs where 2 plasma samples were available from differing time points, pNfL concentrations were measured to evaluate alterations over time. RESULTS: No significant difference in pNfL concentration was found between ILP Cases and Control (P = .36). pNfL concentrations had moderate negative correlations with weight and height in the Control group; other variables did not correlate with pNfL concentrations in ILP Case or Control groups. pNfL concentrations do not correlate with ILP disease status or duration in Labrador Retrievers. CLINICAL RELEVANCE: There is no evidence that pNfL levels are altered due to ILP disease duration or progression when compared with healthy controls. When evaluating pNfL concentrations in the dog, weight and height should be considered.

A retrospective study of the efficacy of zonisamide in controlling seizures in 57 cats.

BACKGROUND: Evidence-based recommendations for antiepileptic drug selection in cats beyond phenobarbital are limited, and additional studies are needed for cats where seizures remain inadequately controlled by administration of phenobarbital alone or for cats that cannot safely receive phenobarbital. OBJECTIVE: To compare seizure frequency in cats before and after oral administration of zonisamide and describe adverse clinical or clinicopathologic effects in this cohort. ANIMALS: Fifty-seven cats with a history of seizures. METHODS: Multicenter, retrospective study. Median number of seizures per month and number of seizure days per month were compared before and after administration of zonisamide in all cats, a subgroup of cats with idiopathic epilepsy (IE), and a subgroup of cats receiving zonisamide as sole therapy. Clinical and clinicopathologic adverse effect data were also reported. RESULTS: A median decrease of 1 (P = .001, 95% confidence interval (CI) [-1.0, -0.5]) seizure per month, and 1 (P = .003, 95% CI [-1.5, -0.2]) seizure days per month was found across all cats after oral administration of zonisamide. The subgroup with IE showed median decreases of 1 (P = .03, 95% CI [-2.0, -0.5]) and 2 (P = .01, 95% CI [-2.5, -1.0]), respectively. The most common clinical adverse effects were sedation (17%), ataxia (11%), hyporexia (17%), and emesis (5%). One cat developed mild nonregenerative anemia, 2 cats developed mild metabolic acidosis, and 6 cats showed mild increases in ALT and ALP. CONCLUSION: Zonisamide was well tolerated and efficacious in controlling seizure activity in most cats.

Rapport de cas Ossifying fibroma in the cervical vertebra of a dog.

The objective of this study was to describe the clinical signs, neurologic examination findings, diagnostic imaging results, and pathologic diagnosis of ossifying fibroma in the cervical vertebra of a dog. A 3-year-old spayed female Pembroke Welsh corgi dog exhibited severe cervical pain and left-sided postural reaction deficits. Magnetic resonance imaging (MRI) revealed a lobulated contrast enhancing mass associated with the C6 cervical vertebra. Due to the lack of response to pain medications, humane euthanasia was elected, and histopathologic evaluation of the mass revealed a fibro-osseous lesion most consistent with an ossifying fibroma. This neoplasm is most commonly associated with the mandible of young horses and has not been previously reported in vertebrae in veterinary medicine. Key clinical message: This case is the first report of a fibro-osseous lesion most consistent with an ossifying fibroma affecting a vertebra in veterinary medicine.

Fibrome ossifiant dans la vertèbre cervicale d'un chien. Décrire les signes cliniques, les résultats de l'examen neurologique, les résultats de l'imagerie diagnostique et le diagnostic pathologique du fibrome ossifiant dans la vertèbre cervicale d'un chien. Une chienne Pembroke Welsh corgi femelle stérilisée âgée de 3 ans présentait de fortes douleurs cervicales et des déficits de réaction posturale du côté gauche. L'imagerie par résonance magnétique (IRM) a révélé une masse lobulée augmentant le contraste associée à la vertèbre cervicale C6. En raison de l'absence de réponse aux analgésiques, l'euthanasie a été choisie et l'évaluation histopathologique de la masse a révélé une lésion fibro-osseuse plus compatible avec un fibrome ossifiant. Ce néoplasme est le plus souvent associé à la mandibule des jeunes chevaux et n'a jamais été signalé auparavant dans les vertèbres en médecine vétérinaire.Message clinique clé :Ce cas est le premier rapport d'une lésion fibro-osseuse plus compatible avec un fibrome ossifiant touchant une vertèbre en médecine vétérinaire.(Traduit par Dr Serge Messier).

Diagnosis and successful management of an extradural compressive hematoma secondary to diphacinone poisoning in a dog.

OBJECTIVE: To describe the successful case management of an extradural hematoma secondary to anticoagulant rodenticide toxicity causing spinal compression and paraplegia. CASE SUMMARY: A 3-month-old, female intact, mixed breed dog was presented for a 12-hour history of paraplegia. CBC and biochemistry results were unremarkable, and a coagulation panel revealed prolonged prothrombin time with normal activated partial thromboplastin time. Magnetic resonance imaging revealed an extradural compressive lesion within the vertebral canal extending from T6 to T11, most consistent with an extradural hematoma. Further coagulation testing revealed a coagulopathy caused by vitamin K1 deficiency and confirmed exposure to the anticoagulant rodenticide, diphacinone. The dog was medically managed with fresh frozen plasma, aminocaproic acid, and oral vitamin K1 therapy. A right-sided T6 to T11 hemilaminectomy was later performed for removal of the extradural hematoma and spinal decompression. The dog's neurological status gradually improved postoperatively and, at the time of discharge, was nonambulatory paraparetic with voluntary micturition. Four weeks postoperatively, the dog had normal prothrombin and activated partial thromboplastin times and was nonambulatory paraparetic with strong motor function. NEW OR UNIQUE INFORMATION PROVIDED: This is the first reported case of a dog with an extradural hematoma secondary to anticoagulant rodenticide causing spinal cord compression and neurological deficits. Surgical management of this case was successful and resulted in improvement of neurological signs. Extradural hematoma should be considered as a potential location of bleeding in rodenticide toxicity as well as a differential diagnosis in patients with neurological deficits.

Effects of trazodone administration on the neurologic examination in healthy dogs.

BACKGROUND: Trazodone is an anxiolytic used PO to decrease anxiety in dogs. Whether or not trazodone affects the neurologic examination in dogs has not been previously reported. OBJECTIVE: Investigate whether trazodone administration is associated with changes in the neurologic examination in healthy dogs. ANIMALS: Thirty-two healthy dogs between 1 and 6 years old with no previously diagnosed medical conditions and perceived by their owners as neurologically normal. METHODS: Baseline sedation and anxiety assessments and neurologic examination were performed on each dog, followed by trazodone administration (6.25-8.60 mg/kg PO). The sedation and anxiety assessments and neurologic examination were repeated 2.5 hours after trazodone administration. The examinations were performed by a single board-certified veterinary neurologist and were video-recorded. The videos were randomized and reviewed by a different neurologist, blinded to the previous evaluations, who scored the examinations. RESULTS: Seven of 32 (22%) dogs had worse scores on their neurologic examination after receiving trazodone, manifesting as new or progressive PR deficits. Although not clinically relevant, 18.7% of the dogs had consciousness levels that changed from bright, alert, responsive to quiet, alert, responsive after trazodone administration. No other changes were observed on neurologic examination. Sedation and anxiety scores were significantly different after trazodone administration compared to before (P < .001 and P < .001, respectively). CONCLUSIONS AND CLINICAL IMPORTANCE: Most dogs did not have changes on neurologic examination after trazodone administration. However, approximately 20% of dogs had new or worsening PR deficits after receiving trazodone. Ideally, trazodone should not be given before neurologic examination in dogs.

Glossitis in an older non-corgi dog: Diagnosis and long-term follow-up.

A 9-year-old spayed female 18.8 kg mixed breed boxer dog was referred for evaluation of a 7-month history of difficulty swallowing and prehending food, regurgitation, hypersalivation, and an abnormal dorsiflexion of the tongue. Prior to referral, a barium study was performed, which revealed a mildly dilated esophagus. Treatment with sucralfate, cisapride, and prednisone was initiated. Physical examination revealed bilateral, symmetric atrophy of the temporalis muscles, dorsiflexion of the distal aspect of the tongue with concurrent muscle atrophy, and a reduced gag reflex. Electrodiagnostic examinations revealed spontaneous electrical activity in the muscles of mastication and tongue. Biopsies from the right temporalis, tongue, and biceps femoris muscles were collected. An immune-mediated myositis with fibrosis, scattered CD3, CD4, and CD8+ T-lymphocytes, and upregulation of markers for major histocompatibility antigens were observed in the tongue and temporalis muscles. The dog was treated with a tapering course of prednisone over 2 months and cyclosporine long-term. The dog was maintained on cyclosporine alone for > 2 years and clinical signs remained static, although multiple episodes of aspiration pneumonia occurred. Ultimately, euthanasia was performed due to chronic kidney disease with associated anemia, lethargy, and anorexia.

Glossite chez un chien âgé non-corgi : diagnostic et suivi à long terme. Une chienne boxer de race mixte de 18,8 kg stérilisée âgée de 9 ans a été référée pour l'évaluation d'une histoire de 7 mois de difficulté à avaler et de préhension des aliments, de régurgitation, d'hypersalivation et d'une dorsiflexion anormale de la langue. Avant la référence, un examen baryté a été réalisée et a révélé un oesophage légèrement dilaté. Un traitement par sucralfate, cisapride et prednisone a été initié. L'examen physique a révélé une atrophie bilatérale et symétrique des muscles temporaux, une flexion dorsale de la face distale de la langue avec atrophie musculaire concomitante et un réflexe nauséeux réduit. Les examens électrodiagnostiques ont révélé une activité électrique spontanée dans les muscles de la mastication et de la langue. Des biopsies des muscles temporaux droits, de la langue et du biceps fémoral ont été recueillies. Une myosite à médiation immunitaire avec fibrose, des lymphocytes T CD3, CD4 et CD8+ dispersés et une régulation positive des marqueurs des principaux antigènes d'histocompatibilité ont été observées dans la langue et les muscles temporaux. Le chien a été traité avec une posologie décroissante de prednisone sur 2 mois et de cyclosporine à long terme. Le chien a été maintenu sous cyclosporine seule pendant > 2 ans et les signes cliniques sont restés stables, bien que plusieurs épisodes de pneumonie par aspiration se soient produits. En fin de compte, l'euthanasie a été pratiquée en raison d'une maladie rénale chronique associée à une anémie, une léthargie et une anorexie.(Traduit par Dr Serge Messier).

Case Report: Bordetella bronchiseptica Meningoencephalomyelitis in a Dog.

A 15-month-old male neutered Wirehaired Pointer mixed-breed dog presented with fever and cervical pain. Cerebrospinal fluid (CSF) analysis showed neutrophilic pleocytosis with intracellular bacteria, and culture of CSF grew Bordetella bronchiseptica. The patient became non-ambulatory 3 days after CSF collection. He was treated with low-dose prednisone for 3.5 months and doxycycline for 1 year. Recheck CSF analysis 1 month after diagnosis showed reduction of inflammation and 3 months after diagnosis revealed only increased protein. The patient improved neurologically over several months and was weakly ambulatory 5 months and fully ambulatory 7 months after diagnosis. Whole genome sequencing of the bacterial isolate and a live modified intranasal vaccine similar to the one the dog had been vaccinated with 7 weeks before diagnosis was similar but not an exact match. Bacterial meningitis should be considered, and culture of CSF is recommended, in cases of neutrophilic pleocytosis of CSF.

Incidence of hepatopathies in dogs administered zonisamide orally: A retrospective study of 384 cases.

BACKGROUND: Acute hepatopathy secondary to administration of zonisamide has been reported in 2 dogs, but overall incidence of hepatopathy is unknown. OBJECTIVE: To characterize the incidence of hepatopathy in dogs administered zonisamide PO. ANIMALS: Three hundred eighty-four dogs administered zonisamide PO. METHODS: Multicenter retrospective study. Medical records were searched for dogs prescribed zonisamide PO and which had follow-up for at least 3 months (acute exposure) and >3 months (chronic exposure). Reported clinical signs, physical examination findings, and serum biochemical panels were reviewed for possible hepatotoxicosis. Serum alanine aminotransferase (ALT) and alkaline phosphatase (ALP) activity and albumin concentration were documented for all available cases. RESULTS: Acute clinical hepatopathy was found in 2 of 384 treated dogs (0.52%, 95% confidence interval [CI], 0.06-1.9) after 13-16 days of zonisamide treatment. One additional dog had elevated serum ALT activity with no clinical signs. Of these 3 dogs, 2 recovered after administration of zonisamide was stopped, and 1 was euthanized because of liver failure. Of the 117 cases chronically administered zonisamide, 10 had an increase in ALP, 6 had an increase in ALT, and 1 had hypoalbuminemia. No clinical signs of liver disease were noted in dogs chronically treated with zonisamide (median, 20 months; range, 5-94 months). CONCLUSIONS AND CLINICAL IMPORTANCE: Acute, potentially life-threatening hepatopathy associated with oral administration of zonisamide to dogs is estimated to occur in less than 1% of dogs and was observed in the first 3 weeks of treatment. Subclinical abnormalities in ALT and ALP activity were noted in <10% of dogs during chronic administration of zonisamide, with no clinical signs of liver disease noted.

The prognostic value of admission point-of-care testing and modified Glasgow Coma Scale score in dogs and cats with traumatic brain injuries (2007-2010): 212 cases.

OBJECTIVE: To investigate the association between admission point-of-care parameters and survival to discharge in dogs and cats with traumatic brain injury (TBI). DESIGN: Retrospective study 2007-2010. SETTING: A rural university teaching hospital and an urban private practice teaching hospital. ANIMALS: One hundred thirty-one dogs and 81 cats admitted to the emergency service with evidence of head injury based on history from the owner or physical exam. MEASUREMENTS AND MAIN RESULTS: In dogs, nonsurvivors had significantly higher glucose concentrations at admission than survivors (median = 8.49 mmol/L [153 mg/dl] vs 6.83 mmol/L [123 mg/dl], p = 0.039). In cats, there was no significant difference in admission glucose between survivors and nonsurvivors (median = 10.21 mmol/L [184 mg/dl] vs 10.93 mmol/L [197 mg/dl], p = 0.17). Modified Glasgow Coma Scale (MGCS) score was available for 105 of the 131 dogs (80%) and was significantly higher in survivors than in nonsurvivors (median = 16 vs 11, p < 0.0001). MGCS was available for 45 of the 81 cats (56%) and was significantly higher in survivors than in nonsurvivors (median = 17 vs 14, p = 0.0005). The relative prognostic value of the admission point-of-care testing parameters and MGCS were assessed using a stepwise linear regression model, which included admission glucose, pH, base excess, sodium, and MGCS. In dogs, only admission glucose was an independent predictor of survival (odds ratio = 1.027, 95% confidence interval, 1.0042-1.05, p = 0.019). CONCLUSIONS: These results suggest that, as in people with TBI, increased blood glucose concentrations may have prognostic significance in dogs with TBI but not in cats. In addition, MGCS score may be predictive of survival in both dogs and cats with TBI.

Daytime and nocturnal activity in treated dogs with idiopathic epilepsy compared to matched unaffected controls.

BACKGROUND: In dogs, antiepileptic drugs (AED) cause lethargy but quantitative data regarding the effects of AED on activity levels are not available, and little is known about how AEDs affect sleep quality. OBJECTIVE: To quantitatively compare activity levels and nocturnal activity in dogs previously diagnosed with idiopathic epilepsy (IE) receiving AEDs compared to age- and breed-matched control dogs. ANIMALS: Sixty-two dogs with IE and 310 control dogs. METHODS: This is a 3-month prospective parallel observational study. An activity monitoring device for dogs was used to measure daily activity levels and sleep scores in all dogs. RESULTS: Dogs with IE treated with AEDs had an 18% average lower baseline activity level compared to control dogs (P = .005; point estimate = 0.82, 95% confidence interval [CI], 0.75-0.90). The combination of phenobarbital and potassium bromide (KBr) was associated with an average 28% decrease in activity in dogs with IE compared to control dogs (P = .03; point estimate = 0.72; CI, 0.62-0.82). Mean sleep scores were not significantly different in dogs with IE receiving AEDs compared to control dogs (P = .43). However, higher dosages of KBr were associated with lower sleep scores (P = .01). CONCLUSIONS: Dogs with IE receiving AEDs have lower activity levels, but no difference in sleep scores, compared to controls. The combination of phenobarbital and KBr had the largest decrease in activity between groups. Higher doses of KBr may affect nocturnal activity in epileptic dogs.

Aventriculi associated with holoprosencephaly in a dog.

CASE DESCRIPTION: A 10-month-old neutered male mixed breed dog was presented for assessment of poorly controlled seizures. CLINICAL FINDINGS: Magnetic resonance imaging of the brain disclosed complete absence of the lateral and third ventricles and mesencephalic aqueduct. Postmortem computed tomographic (CT) imaging and positive contrast cisterno-ventriculography confirmed the lack of a contiguous ventricular system. However, histopathology identified the presence of vestigial lateral and third ventricles with hypoplastic choroid plexus, atresia of the third ventricle, and fused thalami, consistent with a diagnosis of lobar holoprosencephaly (HPE). CLINICAL RELEVANCE: To our knowledge, this report is the first case of radiographically confirmed aventriculi associated with HPE, a rare congenital malformation previously reported in people, to be described in veterinary medicine.

Proportional loss of parvalbumin-immunoreactive synaptic boutons and granule cells from the hippocampus of sea lions with temporal lobe epilepsy.

One in 26 people develop epilepsy and in these temporal lobe epilepsy (TLE) is common. Many patients display a pattern of neuron loss called hippocampal sclerosis. Seizures usually start in the hippocampus but underlying mechanisms remain unclear. One possibility is insufficient inhibition of dentate granule cells. Normally parvalbumin-immunoreactive (PV) interneurons strongly inhibit granule cells. Humans with TLE display loss of PV interneurons in the dentate gyrus but questions persist. To address this, we evaluated PV interneuron and bouton numbers in California sea lions (Zalophus californianus) that naturally develop TLE after exposure to domoic acid, a neurotoxin that enters the marine food chain during harmful algal blooms. Sclerotic hippocampi were identified by the loss of Nissl-stained hilar neurons. Stereological methods were used to estimate the number of granule cells and PV interneurons per dentate gyrus. Sclerotic hippocampi contained fewer granule cells, fewer PV interneurons, and fewer PV synaptic boutons, and the ratio of granule cells to PV interneurons was higher than in controls. To test whether fewer boutons was attributable to loss versus reduced immunoreactivity, expression of synaptotagmin-2 (syt2) was evaluated. Syt2 is also expressed in boutons of PV interneurons. Sclerotic hippocampi displayed proportional losses of syt2-immunoreactive boutons, PV boutons, and granule cells. There was no significant difference in the average numbers of PV- or syt2-positive boutons per granule cell between control and sclerotic hippocampi. These findings do not address functionality of surviving synapses but suggest reduced granule cell inhibition in TLE is not attributable to anatomical loss of PV boutons.

Characteristics and Survival of 121 Cats Undergoing Excision of Intracranial Meningiomas (1994-2011).

OBJECTIVE: To report clinical features and outcomes of cats undergoing excision of intracranial meningiomas. STUDY DESIGN: Retrospective, multicenter case series. SAMPLE POPULATION: One hundred and twenty-one cats. METHODS: Signalment, clinical signs, duration of clinical signs, preoperative drug therapy, diagnostic imaging reports, surgery, histopathology, and outcome were collected from records of cats undergoing excision of intracranial meningiomas. Survival estimates were made using Kaplan-Meier analysis. RESULTS: There were 76/121 neutered males and 83/121 domestic short-hairs. Body weight ranged from 1.5-8.7 kg (median 5.0 kg). Age at diagnosis ranged from 3-18 years (median 12 years). Clinical signs included changes in behavior, ataxia, seizures, visual deficits, circling, and paresis. Duration of neurologic signs ranged from <1-23 months (median 1.25 months). At the time of writing, 13 cats were alive, 54 were dead or euthanatized, and 54 were lost to followup. Seven cats (13% of cats that died; 6% of all cats) died or were euthanatized in the immediate postoperative period (<1 month post-surgery) and 9 cats (17% of all cats that died; 7% of all cats) died from causes related to the meningioma but outside the immediate perioperative period. The median survival time for all cats was 37 months (95% confidence interval 28-54 months). CONCLUSION: Cats undergoing excision of intracranial meningiomas had a low perioperative mortality and a long-term prognosis of more than 3 years.