Search

Bovine familial convulsions and ataxia (BFCA) is considered an autosomal dominant syndrome with incomplete penetrance. Nine Angus calves from the same herd were diagnosed with BFCA within days of birth. Necropsy revealed cerebellar and spinal cord lesions associated with the condition. Parentage testing confirmed that all affected calves had a common sire. The sire was then bred to 36 cows across two herds using artificial insemination, producing an additional 14 affected calves. The objective of this investigation was to identify hypothesized dominant genetic variation underlying the condition. Whole-genome sequencing was performed on the sire, six affected and seven unaffected paternal half-sibling calves and combined with data from 135 unrelated controls. The sire and five of the six affected calves were heterozygous for a nonsense variant (Chr7 g.12367906C>T, c.5073C>T, p.Arg1681*) in CACNA1A. The other affected calves (N = 8) were heterozygous for the variant but it was absent in the other unaffected calves (N = 7) and parents of the sire. This variant was also absent in sequence data from over 6500 other cattle obtained via public repositories and collaborator projects. The variant in CACNA1A is expressed in the cerebellum of the ataxic calves as detected in the transcriptome and was not differentially expressed compared with controls. The CACNA1A protein is part of a highly expressed cerebellar calcium voltage gated channel. The nonsense variant is proposed to cause haploinsufficiency, preventing proper transmission of neuronal signals through the channel and resulting in BFCA., (© 2024 The Authors. Animal Genetics published by John Wiley & Sons Ltd on behalf of Stichting International Foundation for Animal Genetics.)

Background: High concentrations of complement factors are presented in serum of animal epilepsy models and human patients with epilepsy., Objectives: To determine whether complement dysregulation occurs in dogs with idiopathic epilepsy (IE)., Animals: The study included 49 dogs with IE subgrouped into treatment (n = 19), and nontreatment (n = 30), and 29 healthy dogs., Methods: In this case-control study, the serum concentrations of the third (C3) and fourth (C4) components of the complement system were measured using a canine-specific ELISA kit., Results: Serum C3 and C4 concentrations were significantly higher in dogs with IE (C3, median; 4.901 [IQR; 3.915-6.673] mg/mL, P < .001; C4, 0.327 [0.134-0.557] mg/mL, P = .03) than in healthy control dogs (C3, 3.550 [3.075-4.191] mg/mL; C4, 0.267 [0.131-0.427] mg/mL). No significant differences were observed in serum C3 and C4 concentrations between dogs in the treatment (C3, median; 4.894 [IQR; 4.192-5.715] mg/mL; C4, 0.427 [0.143-0.586] mg/mL) and nontreatment groups (C3, 5.051 [3.702-7.132] mg/mL; C4, 0.258 [0.130-0.489] mg/mL). Dogs with a seizure frequency >3 times/month had significantly higher serum C3 (6.461 [4.695-8.735] mg/mL; P < .01) and C4 (0.451 [0.163-0.675] mg/mL; P = .01) concentrations than those with a seizure frequency ≤3 times/month (C3, 3.859 [3.464-5.142] mg/mL; C4, 0.161 [0.100-0.325] mg/mL)., Conclusions and Clinical Importance: Dysregulation of classical complement pathway was identified in IE dogs. Serum C3 and C4 concentrations could be diagnostic biomarkers for IE in dogs with higher seizure frequency., (© 2024 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Objective: To describe seizure activity in juvenile dogs successfully weaned from long-term mechanical ventilation., Case Series Summary: Three juvenile dogs (all approximately 3 months old) underwent long-term mechanical ventilation with IV anesthesia for suspected noncardiogenic pulmonary edema. Within 24 hours of extubation and within 10 hours of discontinuing midazolam continuous infusions, all dogs experienced seizures, which is 1 sign of iatrogenic withdrawal syndrome. Each dog was treated with an anticonvulsant protocol, and none experienced seizures after being discharged., New or Unique Information Provided: Each dog received IV anesthesia, including fentanyl, dexmedetomidine, midazolam, and propofol, during mechanical ventilation and subsequently experienced seizures after successful weaning from mechanical ventilation. Juvenile dogs may be at risk for seizures after weaning from mechanical ventilation and IV anesthesia. Neurological monitoring and further research into an appropriate weaning protocol may prove beneficial in juvenile dogs requiring prolonged anesthesia., (© Veterinary Emergency and Critical Care Society 2024.)

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., (© 2024 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Background: Surgical excision is the treatment of choice for feline intracranial meningioma., Objectives: To report clinical findings, complications, and outcomes following surgery for feline intracranial meningioma., Methods: Medical records (01/2000-01/2017) of cats that underwent surgical excision of an intracranial meningioma at our institution were reviewed. Patient data included signalment, clinical signs, surgical technique, complications, histopathologic diagnosis, survival time, and owners' answers to a satisfaction questionnaire. Survival was assessed using the Kaplan-Meier method and log-rank test., Results: Twenty-six cats were included in this study. The exact cause of death was known in 17 cases and was not related to meningioma in 9/17 cases. Overall median survival time was 881 days (95% confidence interval 518; 1248). The age of the cat did not influence survival ( p = 0.94) or the occurrence of complications ( p = 0.051). Complications occurred in 13/24 cats, including dramatic complications in 4/24 cats. Most complications appeared in the first 24 hours post-surgery (12/13). Males had more postoperative complications ( p = 0.042), including more seizures ( p = 0.016). Cats with cranioplasty had fewer complications ( p = 0.021). Clinical recurrence was confirmed in 3 out of 17 cats. Recurrence-free survival time was 826 days. Most owners (12/14) were satisfied with the outcome., Conclusions: Surgical treatment of intracranial meningioma in cats was associated with a long median survival time but also with a high rate of minor and major postoperative complications, including early postoperative seizures. Cranioplasty may reduce complications. Age at the time of surgery had no effect on outcomes., Competing Interests: The authors declare no conflicts of interest., (© 2024 The Korean Society of Veterinary Science.)

Objective: To report the clinical perioperative, short-term, and long-term outcomes for cats undergoing ameroid ring constrictor (ARC) attenuation of a congenital extrahepatic portosystemic shunt (EHPSS)., Study Design: Retrospective case series from a single veterinary teaching hospital (2002-2020)., Animals: Twenty client-owned cats with EHPSS., Methods: Data collected from medical records included signalment, history, physical examination, clinicopathologic testing, medications, diagnostic imaging, intraoperative findings, perioperative complications, and postoperative clinical outcomes. Long-term clinical outcome was obtained from a standardized owner interview or medical records., Results: Perioperative complications were reported in five cats out of 20, including blindness (two cats), ascites (one cat), head pressing (one cat), and seizures and death (one cat). Short-term clinical outcome was excellent in 14/18 cats, good in 2/18 cats, and poor in 2/18 cats that were available for follow up, and long term clinical outcome was excellent in 15/18, good in 1/18 cats, and poor in 2/18 cats that were available for follow up., Conclusion: Long-term clinical outcome was good or excellent in 16/18 of cats available for follow up. Perioperative complications were reported in five cats., Clinical Significance: Surgical attenuation of EHPSS with an ARC can result in resolution of clinical signs and biochemical abnormalities in the majority of cats. The perioperative complication rate for feline patients with EHPSS attenuated with an ARC was lower than reported historically. Seizures may persist in the long term despite normal bile acid stimulation test results, complete blood count, and biochemistry analysis., (© 2023 American College of Veterinary Surgeons.)

Background: Emergency cases can present at any time of the day or night. All small animal practitioners need to have the skills to triage and stabilize common emergency cases even if they ultimately aim to refer the patient to another facility., Objectives and Procedures: The first part of this 3-part review article series covers respiratory distress and seizures. A stepwise approach to categorize and stabilize these cases is outlined, along with helpful tips to optimize the referral experience, if indicated., Results: Having a strong methodical approach to animals in respiratory distress optimizes treatment. Similarly, achieving cessation of seizures, along with having a good understanding of the causes of seizures, allows for patient stabilization., Conclusion and Clinical Relevance: Do NOT refer emergent cases before completing basic stabilization. Many emergency cases do not require emergent referral and can be worked up by the primary veterinarian or sent to a referral clinic on an appointment basis after appropriate stabilization steps are completed., (Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.)

Background: Juvenile idiopathic epilepsy (JIE) is categorized as a generalized epilepsy. Epilepsy classification entails electrocortical characterization and localization of epileptic discharges (ED) using electroencephalography (EEG)., Hypothesis/objectives: Characterize epilepsy in Egyptian Arabian foals with JIE using EEG., Animals: Sixty-nine foals (JIE, 48; controls, 21)., Methods: Retrospective study. Inclusion criteria consisted of Egyptian Arabian foals: (1) JIE group diagnosed based on witnessed or recorded seizures, and neurological and EEG findings, and (2) control group of healthy nonepileptic age-matched foals. Clinical data were obtained in 48 foals. Electroencephalography with photic stimulation was performed under standing sedation in 37 JIE foals and 21 controls., Results: Abnormalities on EEG were found in 95% of epileptic foals (35 of 37) and in 3 of 21 control asymptomatic foals with affected siblings. Focal ED were detected predominantly in the central vertex with diffusion into the centroparietal or frontocentral regions (n = 35). Generalization of ED occurred in 14 JIE foals. Epileptic discharges commonly were seen during wakefulness (n = 27/37 JIE foals) and sedated sleep (n = 35/37 JIE foals; 3/21 controls). Photic stimulation triggered focal central ED in 15 of 21 JIE foals., Conclusions and Clinical Importance: Juvenile idiopathic epilepsy has a focal onset of ED at the central vertex with spread resulting in clinical generalized tonic-clonic seizures with facial motor activity and loss of consciousness. Electroencephalography with photic stimulation contributes to accurate phenotyping of epilepsy. Foals with this benign self-limiting disorder might serve as a naturally occurring animal model for self-limited epilepsy in children., (© 2023 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Background: Nonconvulsive seizures (NCS) and nonconvulsive status epilepticus (NCSE) are frequently observed in human patients. Diagnosis of NCS and NCSE only can be achieved by the use of electroencephalography (EEG). Electroencephalographic monitoring is rare in veterinary medicine and consequently there is limited data on frequency of NCS and NCSE., Objectives: Determine the prevalence of NCS and NCSE in dogs and cats with a history of cluster seizures., Animals: Twenty-six dogs and 12 cats., Methods: Retrospective study. Medical records of dogs and cats with cluster seizures were reviewed. Electroencephalography was performed in order to identify electrographic seizure activity after the apparent cessation of convulsive seizure activity., Results: Nonconvulsive seizures were detected in 9 dogs and 2 cats out of the 38 patients (29%). Nonconvulsive status epilepticus was detected in 4 dogs and 2 cats (16%). Five patients had both NCS and NCSE. A decreased level of consciousness was evident in 6/11 patients with NCS, 3/6 also had NCSE. Mortality rate for patients with NCS (73%) and NCSE (67%) was much higher than that for patients with no seizure activity on EEG (27%)., Conclusion and Clinical Importance: Prevalence of NCS and NCSE is high in dogs and cats with a history of cluster seizures. Nonconvulsive seizures and NCSE are difficult to detect clinically and are associated with higher in hospital mortality rates. Results indicate that prompt EEG monitoring should be performed in dogs and cats with cluster seizures., (© 2023 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Background: C-reactive protein (CRP) is an acute-phase protein produced by the liver during systemic inflammation. In humans, some epilepsies are associated with increased serum CRP (sCRP) concentrations, but this has yet to be proven in veterinary studies. Dogs with structural epilepsy (SE) and normal interictal neurological examination are hard to distinguish from dogs with idiopathic epilepsy (IE) without the use of advanced imaging., Methods: The study included eight dogs with SE and 12 dogs with IE from a referral hospital population. This was a retrospective observational cohort study. The Mann-Whitney test was used to compare the sCRP concentrations within 24 hours of the last epileptic seizure between dogs with SE or IE., Results: Dogs with SE had higher sCRP concentrations than dogs with IE (8.9 [range <2.2-53.2] mg/L vs. <2.2 [range <2.2-6.9] mg/L; p = 0.043). Five of the eight (62%) dogs with SE had an sCRP concentration above the reference interval, compared with none of the 12 dogs with IE., Limitations: The small sample size was the major limitation of this study. Other inflammatory causes were also not exclusively ruled out, although further clinical investigations were not indicated., Conclusions: This study found that sCRP concentrations were higher in this cohort of dogs with SE than in those with IE. Further studies with larger cohorts of dogs are warranted to validate if sCRP can be used as an additional biomarker for SE., (© 2023 The Authors. Veterinary Record published by John Wiley & Sons Ltd on behalf of British Veterinary Association.)

Background: Phenobarbital (PB) is used as a first-line treatment for recurrent epileptic seizures in cats. While hematologic abnormalities are well-known side effects of antiepileptic therapy with PB in humans and dogs, little is known about such alterations in cats., Objectives: The aim of this retrospective study was to investigate the prevalence and clinical relevance of cytopenia during PB treatment in cats., Methods: In this single-center, retrospective clinical study, 69 cats-with suspected idiopathic epilepsy admitted to the Small Animal Clinic of the University of Veterinary Medicine in Vienna (VMU)-were included. A complete blood count for each patient was performed, and changes in hematocrit, leukocytes, neutrophils, and thrombocytes were documented and graded., Results: Fifty-three out of 69 cats (76.8%) showed cytopenias with a reduction of at least one cell fraction during PB treatment. The most frequent change was neutropenia (60%), followed by leukopenia (49.3%), thrombocytopenia (24.1%), and anemia (20.3%). Most of the changes were mild or moderate; only one patient (1.5%) showed severe leukopenia and neutropenia, and one was a life-threatening neutropenia (1.5%) with a serum PB concentration within or even below the therapeutic range. These patients did not present with clinical symptoms other than those related to epileptic episodes. Cats who received combination therapy showed lower hematocrits than those who received monotherapy. A tendency for leukocytes and neutrophils to decrease during PB treatment was also seen., Conclusions: Blood cytopenias may frequently occur in cats on chronic PB therapy, even when serum drug levels are within the therapeutic range. However, clinical signs are typically mild to moderate and rarely severe., (© 2023 The Authors. Veterinary Clinical Pathology published by Wiley Periodicals LLC on behalf of American Society for Veterinary Clinical Pathology.)

Objective: To assess the clinical efficacy and plasma concentrations of levetiracetam in a goat with seizures., Animal: A 5-month-old doeling., Clinical Presentation, Progression, and Procedures: The goat was referred because of progressive anorexia and lethargy over 3 days. Clinical signs consisted of weakness, obtundation, opisthotonos, anisocoria, and cortical blindness. Initial evaluation was most consistent with polioencephalomalacia., Treatment and Outcome: Neurologic improvement occurred within 4 hours of thiamine administration, with appetite returning over 12 hours. On day 3 of hospitalization, the goat suffered acute onset repetitive seizures that were incompletely responsive to standard interventions over 3 hours. Administration of IV levetiracetam (60 mg/kg) produced resolution of seizure activity within 20 minutes. Levetiracetam was continued twice daily IV, then PO after day 6. Plasma concentrations were above or within therapeutic ranges (5 to 45 μg/mL) as previously established for other species, following both IV and PO levetiracetam. Oral administration (60 mg/kg, PO, q 12 h) resulted in plasma levetiracetam concentrations of 48.1 μg/mL 2 hours after a dose and 23.4 μg/mL 2 hours prior to the next dose., Clinical Relevance: Levetiracetam is a newer anticonvulsant commonly used in humans and small animals due to its efficacy, cost, and wide safety margin. Its use has not previously been reported in domestic small ruminants. In this case, levetiracetam showed excellent clinical efficacy in the face of refractory seizures, with no apparent side effects. Plasma concentrations during oral administration were at the high end of the therapeutic range, indicating absorption in a nonmonogastric species. Further studies are warranted to determine optimal dosing in small ruminants.

Background: The long-term effect of implantable vagus nerve stimulators (VNS) on seizures has not been evaluated in epileptic dogs., Objectives: Report seizure frequency in medication-resistant epileptic dogs before and after VNS implantation., Animals: Twelve client-owned dogs with idiopathic epilepsy and >1 seizure day per 3 weeks despite 3 months of appropriate use of 2 antiseizure medications and seizure diaries maintained 6 months before and >12 months after VNS implantation., Methods: Uncontrolled, open-label, before and after study. Mean monthly seizures and inter-seizure periods obtained from contemporaneous seizure diaries in the 6 months before implantation were compared with 0 to 6 months, 7 to 12 months, and subsequent 12-month periods after implantation. The number of dogs with >50% decrease in seizure frequency, >3 times increase in inter-ictal period interval, and seizure freedom for >3 months at the time of death or last follow-up were recorded., Results: Five of 12 dogs were euthanized <12 months after implantation. All 7 remaining dogs showed >50% decrease in seizure frequency until last follow-up, starting at a median of 37 to 48 months after implantation (range, 0-6 to 61-72 months) and a >3-fold increase in mean inter-seizure interval starting a median of 25 to 36 months after implantation (range, 0-6 months to 49-60 months), 3/7 dogs were seizure-free at death or last follow-up., Conclusions and Clinical Importance: Monthly seizure frequencies decreased and inter-seizure intervals increased in all dogs 2 to 3 years after VNS implantation, but a high proportion were euthanized before this time point. Prospective clinical trials are required to establish causality and the magnitude of this association., (© 2023 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Background: Approximately 30% of dogs with idiopathic epilepsy (IE) are drug-resistant. Recent studies have suggested cannabidiol (CBD) may be an effective anticonvulsant in dogs with IE., Objective: To evaluate the addition of CBD to antiseizure drugs (ASDs) on seizure frequency and to report adverse events in dogs with drug-resistant IE., Animals: Fifty-one dogs. Dogs having at least 2 seizures per month while receiving at least 1 ASD were included in the trial., Methods: Double-blinded placebo-controlled crossover study. The 5 mg/kg/day dosage met futility requirements after 12 dogs, and a dosage of 9 mg/kg/day was used in the next 39 dogs. Dogs were randomly assigned to receive CBD or placebo for 3 months, with a 1-month washout period between oils. Total numbers of seizures and seizure days were recorded. Diagnostic testing was performed periodically throughout the trial., Results: At the 9 mg/kg/day dose, the decrease in total seizure frequency was significant compared with placebo. A 24.1% decrease in seizure days occurred in dogs receiving CBD and a 5.8% increase occurred in dogs receiving placebo (P ≤ .05). No significant difference was found in the number of responders (≥50% decrease in total seizures or seizure days). Liver enzyme activities increased at both dosages. Decreased appetite and vomiting were more common in the CBD phase (P ≤ .05)., Conclusions and Clinical Importance: Cannabidiol decreased total seizures and seizure days compared to placebo when administered to dogs PO at 9 mg/kg/day. Liver enzymes should be monitored with administration of CBD in dogs., (© 2023 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Objectives: The present study aimed to evaluate the postoperative quality of life (QOL) after surgery for the treatment of intracranial meningioma in cats., Methods: The study included 14 cases that underwent craniotomy from May 2009 to March 2021. Owners were contacted via telephone after a median time of 967 (range 227-4209) days after surgery and surveyed with a specially designed questionnaire that consisted of three domains, subdivided into different items. Physical behaviour, including general condition, food intake, mobility and overall impression, was evaluated from 0, reflecting the worst status, to 10, reflecting the best. The development of preoperative existing clinical signs, seizures and concurrent medication were evaluated individually for each patient. The time span necessary for the improvement of each item was recorded. Finally, satisfaction about the decision for surgery was ranked from 0 to 10., Results: Thirteen questionnaires were completed. Three cats were evaluated twice owing to revision surgery. Owners reported a statistically significant ( P  <0.001) improvement from immediately after the operation to 240 days after surgery. Preoperative clinical signs resolved in 95% of cases. All questioned owners would opt for surgery again., Conclusions and Relevance: QOL after surgery for intracranial meningioma in cats seems encouraging regarding our study. Nevertheless, limitations, such as small sample size, recall bias, lack of a control group and validation of the questionnaire, need to be kept in mind when interpreting the results., Competing Interests: Conflict of interestThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: The International Veterinary Epilepsy Task Force consensus guidelines recommend performing fasting serum bile acid (SBA) and/or serum ammonia measurements as part of a tier 1 diagnosis of idiopathic epilepsy in dogs. The aim of this retrospective study was to determine the diagnostic utility of fasting SBA in this population., Methods: Dogs that met the tier 1 confidence level diagnosis of idiopathic epilepsy, with the additional requirement of both fasting and 2-hour postprandial SBA measurements, were included. The incidence of significant hepatopathies and usefulness of dynamic SBA testing and minimum database results were analysed., Results: A total of 233 dogs were included. All dogs diagnosed with clinically significant hepatopathy had elevations in postprandial SBA, with eight of 14 (57.14%) showing elevations in fasting SBA. The prevalence of clinically significant hepatopathies that could have been missed without using postprandial SBA measurement was 1.29%., Limitations: The further investigations performed were not uniform and there were limitations in the ability to control sampling techniques due to the retrospective nature of this study. Investigations into hepatopathy were not standardised across this study population., Conclusions: This study documents the importance of postprandial SBA measurements in the detection of hepatopathies and reveals that non-dynamic blood sampling has a negative predictive value of 91% for detecting elevated postprandial SBA, specific to dogs meeting the tier 1 confidence level diagnosis of idiopathic epilepsy., (© 2022 The Authors. Veterinary Record published by John Wiley & Sons Ltd on behalf of British Veterinary Association.)

Background: Idiopathic epilepsy (IE) is a common, chronic brain dysfunction in dogs. Recently, the effect of feeding a diet enriched with medium-chain triglycerides (MCTs) on seizure frequency has been evaluated in several studies in dogs with IE. However, most dogs with IE in previous studies were treated with phenobarbital as the main antiseizure medication (ASM). In Japan, zonisamide (ZNS) is the most prescribed ASM for dogs with IE. The interaction between ZNS and various nutrients including MCTs and the potential effects on treatment efficacy resulting from combining these therapies have not been previously studied. A prospective, randomized, double-blinded, placebo-controlled, crossover dietary study was conducted. Dogs (n = 7) treated with ZNS were fed either a placebo diet (PL) or Purina ProPlan Veterinary Diet NeuroCare (NC) for 3 months, after which treatments were crossed over and continued for another 3 months. Seizure frequency (seizures/month; sz/m), blood tests including concentrations of ZNS and β-hydroxybutyric acid, and owner's visual analogue scale score were collected from all dogs for both treatment periods., Results: There was no significant difference in the seizure frequency between PL (2.95 ± 0.80 sz/m) and NC (1.90 ± 0.57 sz/m) during the 6 months of trial. Three of 7 dogs showed ≥ 50% seizure reduction, and 1 of those 3 dogs achieved seizure freedom in NC period. However, 2 of 7 dogs had no changes in epileptic seizure frequency, 2 of 7 dogs had a deterioration in seizure frequency in the NC period. Feeding the MCT diet concurrent with ZNS showed no apparent adverse effects and did not affect ZNS concentration., Conclusions: This study indicated that the commercially available MCT-enriched diet (NC) can be safely used concurrently with ZNS for dogs with IE., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Orthoses and socket prostheses are rarely used orthopaedic devices in veterinary medicine. Recently, more pet owners have sought these treatments for pets with orthopaedic conditions. However, veterinarians often lack substantial scientific evidence on device outcomes and may expect high costs, the main limiting factor, if human orthopaedic market prices are assumed. This discrepancy creates an imbalance between pet owners' expectations, veterinarians' recommendations, and actual patient benefits. To address economic constraints and enhance knowledge about these devices, this study used 3D technology-namely 3D scanning and printing via fused deposition modelling-to design, modify, and manufacture orthoses and socket prostheses for ten patients, including nine dogs and one calf. An equation was devised and applied to all printed devices to streamline the resizing process for sockets and orthoses. The 3D-printed devices were fitted to the patients, and their adaptation was assessed using three novel scales based on prior scientific literature in the small animal orthopaedic field. The orthoses were well-tolerated, with successful and straightforward adaptation. Although socket prostheses were tolerated, the dogs' adaptation was suboptimal, while the calf demonstrated excellent and immediate adaptation., Competing Interests: Declaration of Competing Interest None of the authors has any financial or personal relationships that could inappropriately influence or bias the content of the paper. The Regional Government of Madrid has not involved in any decision about the development of this study., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objectives: Phenobarbital (PB) q12h is the most common treatment recommendation for cats with recurrent epileptic seizures. Medicating cats may be challenging and result in decreased quality of life for both cat and owner. The aim of this retrospective study was to evaluate treatment with oral PB q24h in cats with presumptive idiopathic epilepsy., Methods: Nine cats with presumptive idiopathic epilepsy, receiving oral PB q24h, were included in a retrospective descriptive study., Results: Seizure remission was achieved in 88% (8/9) of the cats and good seizure control in 12% (1/9) of the cats, treated with a mean dose of oral PB of 2.6 mg/kg q24h (range 1.4-3.8 mg/kg). No cats required an increase of their PB frequency at any time during a mean follow-up period of 3.5 years (range 1.1-8.0 years). No cats displayed side effects or issues with compliance at the last recorded follow-up., Conclusions and Relevance: Once-a-day administration of PB for feline epilepsy was safe and resulted in satisfactory seizure control for the nine cats included in this study. The results of this study justify exploring this topic further in larger prospective studies.

The lack of therapeutics that prevent the development of epilepsy, improve disease prognosis or overcome drug resistance represents an unmet clinical need in veterinary as well as in human medicine. Over the past decade, experimental studies and studies in human epilepsy patients have demonstrated that neuroinflammatory processes are involved in epilepsy development and play a key role in neuronal hyperexcitability that underlies seizure generation. Targeting neuroinflammatory signaling pathways may provide a basis for clinically relevant disease-modification strategies in general, and moreover, could open up new therapeutic avenues for human and veterinary patients with drug-resistant epilepsy. A sound understanding of the neuroinflammatory mechanisms underlying seizure pathogenesis in canine patients is therefore essential for mechanism-based discovery of selective epilepsy therapies that may enable the development of new disease-modifying treatments. In particular, subgroups of canine patients in urgent needs, e.g. dogs with drug-resistant epilepsy, might benefit from more intensive research in this area. Moreover, canine epilepsy shares remarkable similarities in etiology, disease manifestation, and disease progression with human epilepsy. Thus, canine epilepsy is discussed as a translational model for the human disease and epileptic dogs could provide a complementary species for the evaluation of antiepileptic and antiseizure drugs. This review reports key preclinical and clinical findings from experimental research and human medicine supporting the role of neuroinflammation in the pathogenesis of epilepsy. Moreover, the article provides an overview of the current state of knowledge regarding neuroinflammatory processes in canine epilepsy emphasizing the urgent need for further research in this specific field. It also highlights possible functional impact, translational potential and future perspectives of targeting specific inflammatory pathways as disease-modifying and multi-target treatment options for canine epilepsy., Competing Interests: Conflict of interest statement Research on pathophysiological mechanisms of epilepsy and new targeting strategies in Heidrun Potschka’s and Eva-Lotta von Rüden’s group is supported by Deutsche ForschungsgemeinschaftPO 681/12-1. HP received funding for consulting, talks and research collaborations from Eisai, Zogenix, Elanco, Roche, Lario/Exeed Epidarex, Arvelle/Angelini, Jazz Pharmaceuticals, Galapagos, and MSD. AT received funding for a research project from Boehringer-Ingelheim. None of the authors has any other financial or personal relationships that could inappropriately influence or bias the content of the paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: The anti-epileptic effects of docosahexaenoic acid (DHA) in dogs and humans remain controversial. The dosage and efficacy of DHA were various in the previous reports., Aim: The effects of high-dose DHA supplementation as add-on therapy for idiopathic epilepsy in dogs were evaluated., Methods: An open-label clinical trial was designed in this pilot study. Six dogs (median age: 6 years) with idiopathic epilepsy were included. All the patients were diagnosed with idiopathic epilepsy using magnetic MRI and cerebrospinal fluid examination (median: 2.0 years before the trial). They had 5-45 seizures and/or auras (median: 9.0) in the month before starting DHA supplementation. DHA was adjunctively administered at doses of 69-166 mg/kg/day without changing other prescriptions., Results: Four of the six patients completed the 6-month observation period. All the patients showed a decrease in seizure frequency of 50% or more within 2-3 months after the start of the administration, and three patients decreased to a frequency of 0-1 per month after 5-6 months. No clear adverse events were observed in the general condition or blood test results in any patients., Conclusion: Although the sample size was small and the study was not a randomized controlled trial, the data suggest that add-on supplementation of DHA could be useful in reducing the frequency of seizures in canine idiopathic epilepsy., Competing Interests: The authors declare that this study was conducted in the absence of any commercial or financial relationships that could be construed as potential conflicts of interest.

Background: Idiopathic epilepsy in cats is a more common disease than previously thought, but little information is available about the medical treatment of feline idiopathic epilepsy., Aim: To assess the therapeutic efficacy and safety of antiseizure medication (ASM) for a minimum of 6 months, including zonisamide (ZNS), in feline idiopathic epilepsy at a referral hospital in Japan., Methods: Twenty cats diagnosed with idiopathic epilepsy treated with ASMs were retrospectively included., Results: Nine cats that were finally treated with phenobarbital (PB) monotherapy reached the primary goal (the seizure frequency after the treatment intervention was less than one seizure every 3 months). Three cats were treated with ZNS monotherapy and two reached the primary goal. Eight cats finally received combination therapy. Two of the three cats receiving PB and ZNS therapy achieved the primary goal, but one was considered no responder. Five cats [PB + diazepam (DZP), ZNS + DZP, and ZNS + levetiracetam + DZP] decreased the seizure frequency and reached the primary goal in all but one cat reached the secondary goal. Adverse events were observed in eight patients, but these were curable. Two patients had vomiting after ZNS monotherapy, one had diarrhea, and another was an increase in sleeping hours., Conclusion: PB was frequently used and seemed effective as both monotherapy and combination therapy. Some cats were treated with ASM protocols containing ZNS. ZNS may be available to treat idiopathic epilepsy in cats. However, ZNS administration may cause adverse events, such as gastrointestinal toxicity, in cats., Competing Interests: The authors declared no potential conflicts of interest for this research, authorship, and/or publication of this article.

Background: Autoimmune mechanisms represent a novel category for causes of seizures and epilepsies in humans, and LGI1-antibody associated limbic encephalitis occurs in cats., Hypothesis/objectives: To investigate the presence of neural antibodies in dogs with epilepsy or dyskinesia of unknown cause using human and murine assays modified for use in dogs., Animals: Fifty-eight dogs with epilepsy of unknown cause or suspected dyskinesia and 57 control dogs., Methods: Serum and CSF samples were collected prospectively as part of the diagnostic work-up. Clinical data including onset and seizure/episode type were retrieved from the medical records. Screening for neural antibodies was done with cell-based assays transfected with human genes for typical autoimmune encephalitis antigens and tissue-based immunofluorescence assays on mouse hippocampus slices in serum and CSF samples from affected dogs and controls. The commercial human und murine assays were modified with canine-specific secondary antibody. Positive controls were from human samples., Results: The commercial assays used in this study did not provide unequivocal evidence for presence of neural antibodies in dogs including one dog with histopathologically proven limbic encephalitis. Low titer IgLON5 antibodies were present in serum from one dog from the epilepsy/dyskinesia group and in one dog from the control group., Conclusion and Clinical Importance: Specific neural antibodies were not detected using mouse and human target antigens in dogs with epilepsy and dyskinesia of unknown origin. These findings emphasize the need for canine-specific assays and the importance of control groups., (© 2023 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC. on behalf of the American College of Veterinary Internal Medicine.)

Autoimmune encephalitis (AE) is an important cause of encephalitis in humans and occurs at a similar rate to infectious encephalitis. It is frequently associated with antibodies against the extracellular domain of neuronal proteins. Among human AE, that with antibodies against leucine-rich glioma-inactivated 1 (LGI1) is one of the most prevalent forms, and was recently described in cats with limbic encephalitis (LE). In this study, we describe a large cohort (n = 32) of cats with AE, tested positive for voltage gated potassium channel (VGKC)-antibodies, of which 26 (81%) harboured LGI1-antibodies. We delineate their clinical and paraclinical features as well as long-term outcomes up to 5 years. Similar to human cases, most cats with LGI1-antibodies had a history of focal seizures (83%), clustering in the majority (88%), with interictal behavioural changes (73%). Among feline AE patients, there was no seizure type or other clinical characteristic that could distinguish LGI1-antibody positive from negative cats, unlike the pathognomic faciobrachial dystonic seizures seen in humans. Although six cats were euthanased in the first year for epilepsy-associated reasons, those attaining at least 1-year survival had good seizure control and quality of life with appropriate veterinary care and medication. Acute-phase immunotherapy (prednisolone) was given to the most severely unwell cases and its effect is retrospectively evaluated in 10 cats. Our data show LGI1-antibodies are an important cause of feline encephalitis, sharing many features with human AE. Further research should examine optimal therapeutic management strategies and the cause of LE in seronegative cats, building on paradigms established in the counterpart human disease., (Copyright © 2023. Published by Elsevier Ltd.)

Drug resistance continues to be a major clinical problem in the therapeutic management of canine epilepsies with substantial implications for quality of life and survival times. Experimental and clinical data from human medicine provided evidence for relevant contributions of intrinsic severity of the disease as well as alterations in pharmacokinetics and -dynamics to failure to respond to antiseizure medications. In addition, several modulatory factors have been identified that can be associated with the level of therapeutic responses. Among others, the list of potential modulatory factors comprises genetic and epigenetic factors, inflammatory mediators, and metabolites. Regarding data from dogs, there are obvious gaps in knowledge when it comes to our understanding of the clinical patterns and the mechanisms of drug-resistant canine epilepsy. So far, seizure density and the occurrence of cluster seizures have been linked with a poor response to antiseizure medications. Moreover, evidence exists that the genetic background and alterations in epigenetic mechanisms might influence the efficacy of antiseizure medications in dogs with epilepsy. Further molecular, cellular, and network alterations that may affect intrinsic severity, pharmacokinetics, and -dynamics have been reported. However, the association with drug responsiveness has not yet been studied in detail. In summary, there is an urgent need to strengthen clinical and experimental research efforts exploring the mechanisms of resistance as well as their association with different etiologies, epilepsy types, and clinical courses., Competing Interests: Declaration of Competing Interest HP has received fees or funding for consulting, talks and research collaborations from Jazz Pharmaceuticals, Eisai, Zogenix, Elanco, Roche, Lario, Exeed Epidarex, Angelini, MSD and Galapagos. AF has received funding from Boehringer Ingelheim, Nestle Purina, MSD and Vetoquinol. WL is co-founder and CSO of PrevEp, Inc. (Bethesda, MD, USA), has received consultancy fees from Lundbeck, AC Immune, Clexio Biosciences, UCB Pharma, Pragma Therapeutics, Boehringer Ingelheim, Pfizer, and Johnson and Johnson, and has served on the advisory boards of Grünenthal, UCB Pharma, and Angelini Pharma. HV served as paid consultant in the field of epilepsy for Boehringer Ingelheim, CEVA animal health, Nestle Purina. AF served as contract researcher for: Nestle Purina, Desitin Pharma and Boehringer Ingelheim. The authors have no other financial or personal relationships with other people or organizations that could inappropriately influence or bias the content of the paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Metaldehyde poisoning in dogs is well known and described issue. Several studies focused on the incidence, epidemiological features, and clinical and pathological findings associated with this intoxication. However, there are no prospective studies of metaldehyde poisoning and late-onset seizures., Aims: To prospectively describe clinical signs, therapeutic management, outcomes, and delayed-onset seizures due to metaldehyde poisoning in dogs., Methods: A 15-month prospective study on dogs with a diagnosis of metaldehyde poisoning, either via phone call to the animal poison control center or analysis at the toxicology laboratory in Lyon, France. Clinical signs, therapeutic management and outcomes, and the late onset of seizures were assessed for at least 3 years., Results: Twenty-six dogs were enrolled in the study. The most prevalent clinical signs were ataxia (18 dogs), convulsions (17), hypersalivation (15), and tremors (15). Treatment was symptomatic (e.g., activated charcoal, emetic therapy, and intravenous fluids) with anticonvulsant therapy (mainly diazepam). The overall survival rate was 81% (21/26 dogs). All dogs that received active charcoal (11/11) or emetic therapy (4/4) survived. Twelve of 17 dogs had convulsions and survived; 9 were followed up for at least 3 years after poisoning, and none had any other seizure episode or neurological sequelae., Conclusion: This prospective study describes clinical signs, therapeutic management and outcome of metaldehyde poisoning in dogs, and late-onset neurologic sequelae. None of the nine cases that were followed for 3 years developed neurological signs after metaldehyde poisoning. Therefore, long-term antiepileptic therapy is not indicated., Competing Interests: The Author declares that there is no conflict of interest.

Absence seizures are a type of generalized onset seizure associated in humans with brief activity interruptions, unresponsiveness and staring. Absence seizures are infrequently reported in veterinary patients, visually indistinguishable from focal seizures, and so may be grouped as non-generalized tonic clonic seizures (non-GTCS). The objective of this retrospective study was to provide a preliminary understanding of the frequency of non-GTCS in dogs and estimate its prevalence by evaluating the distribution of seizure types presented to a referral hospital over 4 years (May 2017-April 2021), as determined from the medical record history and electroencephalography (EEG) diagnostic testing where available. A total of 528 cases were included via a medical record search for dogs with epilepsy and/or seizures presented to the neurology or emergency services. Cases were categorized into seizure types based on reported clinical signs. Each year, 53-63 % of seizure cases were described as generalized tonic clonic seizures (GTCS), 9-15 % GTCS with additional events and 29-35 % suspected non-GTCS. EEG confirmed absence seizures in 12 of 44 EEGs, 5 cases having a history of GTCS and seven without prior GTCS. This preliminary study suggests that non-GTCS may be relatively common as one third of seizure cases in the referral population presented with non-GTCS clinical signs. Prospective studies using EEG are merited to definitively determine the prevalence of these different seizure types in dogs. Acknowledging the impact of these seizures will improve awareness, aiding veterinarians in their recognition, diagnosis and potential treatment options., Competing Interests: Conflict of interest statement None of the authors has any financial or personal relationships that could inappropriately influence or bias the content of the paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Development of postattenuation neurological signs (PANS) is a potentially severe complication after surgical attenuation of congenital portosystemic shunts in cats. This review summarizes findings of 15 publications that report occurrence of PANS in cats. PANS includes seizures but also milder neurologic signs such as blindness, ataxia, abnormal behavior, tremors, and twitching. Incidence of PANS and specifically postattenuation seizures in studies including a minimum of five cats ranges from 14.3% to 62.0% and 0% to 32.0%, respectively. Etiology of PANS in cats is unknown, however, several hypotheses have been proposed including central nervous system disease/derangement, perioperative hypoglycemia and electrolyte disturbances, and postoperative portal hypertension. A number of possible risk factors have been identified including lower grades of intraoperative postocclusion mesenteric portovenography and osmolality at 24 h postoperatively. Evidence for use of prophylactic antiepileptics such as levetiracetam to prevent or reduce incidence of PANS in cats is limited and does not support their use. Because the cause is unknown, treatment is aimed at controlling neurologic signs, preventing progression to more severe signs, and providing general supportive care. Prospective studies comparing the efficacy of different antiepileptics for treatment of PANS in cats are required. Prognosis for recovery is variable and dependent on severity of neurologic signs. For cats surviving to discharge, long-term survival is possible but persistence or recurrence of neurologic signs in the long-term is not uncommon., (© 2023 The Authors. Veterinary Surgery published by Wiley Periodicals LLC on behalf of American College of Veterinary Surgeons.)

The endocannabinoid system (ECS) is an integral neuromodulatory system involved in neuronal development, synaptic plasticity, and homeostasis regarding immunity, as well as brain and other physiological functions such as anxiety, pain, metabolic regulation, and bone growth. Cannabis is a plant that contains exogenous cannabinoids, which have the potential for profound interplay within the ECS as enzymatic inhibitors or receptor-mediated interactions. Activation of cannabinoid receptors leads to various intracellular signaling processes that are involved in cellular functions, but those interactions are diverse due to different affinities of each cannabinoid with relevant receptors. Among the exogenous cannabinoids, cannabidiol (CBD) has drawn attention due to its potential anticancer, antiangiogenic, anti-inflammatory, and antiseizure properties using in vitro and in vivo models. Although scientific evidence is limited in dogs, there appears to be cautious optimism regarding the utilization of CBD in conjunction with other therapeutics for a range of disorders. This review will primarily focus on current scientific research on the efficacy of CBD on seizure, anxiety, osteoarthritis, and atopic dermatitis, following a brief discussion of endo- and exogenous cannabinoids, ECS, their molecular mechanism, and potential side effects in veterinary medicine. Cannabinoid pharmacology and pharmacokinetics will be addressed in the companion Currents in One Health by Schwark and Wakshlag, AJVR, May 2023.

Objective: To investigate caregivers' assessments of outcome in dogs with idiopathic epilepsy (IE) administered levetiracetam (LEV), zonisamide (ZNS), or phenobarbital (PB) monotherapy., Animals: 100 dogs with IE administered LEV (n = 34), ZNS (31), or PB (35) monotherapy between January 1, 2003, and February 6, 2019, and survey responses from their caregivers., Procedures: Information on duration of therapy, adverse effects (AEs), and outcome was obtained from medical record review and caregiver questionnaire., Results: A significant improvement in mean quality of life score was reported during monotherapy (7.7; SD, 2.14) compared to before treatment (6.25; SD, 2.63; P < .0001), with no difference identified between monotherapy groups. Compared to ZNS monotherapy, dogs prescribed PB monotherapy had a significantly younger median age at seizure onset (2.6 vs 4.3 years; P = .024). A significant relationship was identified between the occurrence of reported AEs and monotherapy group, with a higher prevalence in the PB group (77% [27/35]) and a lower prevalence in the ZNS group (39% [12/31]; P = .0066). Treatment failure rates for PB, LEV, and ZNS monotherapy were 51%, 35%, and 45%, respectively, with failure attributed most commonly to inadequate seizure control. No significant difference was identified between groups with respect to rate of or time to failure., Clinical Relevance: Most caregivers reported a favorable outcome with administration of LEV, ZNS, or PB monotherapy to dogs with IE. Phenobarbital is associated with the highest prevalence of AEs but no difference in quality of life score. Prospective controlled studies are needed to further compare the efficacy and safety of these monotherapies in dogs with IE.

Background: Epilepsy is the most common chronic neurological disease in dogs. More than two-thirds of these patients suffer from associated behavioural comorbidities. The latter could have their origin in partially overlapping pathomechanisms, with the intestinal microbiome as a potential key link between them. The current arsenal of drugs for epilepsy management remains limited. Most canine patients continue to have seizures despite treatment and the occurrence of comorbidities is not sufficiently addressed, limiting quality of life of affected dogs and owners. Therefore, novel additional epilepsy management options are urgently needed. The microbiome-gut-brain axis may serve as a new target for the development of innovative multimodal therapeutic approaches to overcome current shortcomings in epilepsy management., Methods: A six-month prospective, randomised, double-blinded, placebo-controlled, crossover, dietary trial was designed to investigate the potential of the psychobiotic Bifidobacterium longum on behavioural comorbidities in canine epilepsy. Seizure semiology will be evaluated as a secondary outcome measure. Thirty-four privately owned dogs are planned to be included in the ongoing study meeting the following inclusion criteria: Dogs displaying increased anxiety/fear behaviour since the start of the idiopathic epilepsy. Tier II confidence level of the International Veterinary Epilepsy Task Force for the diagnosis of idiopathic epilepsy, with a maximum seizure interval of 3 month and a minimum of three generalised seizures within that period and chronically treated with at least one antiseizure drug without improvement in seizure frequency Each dog will receive the allocated supplement (probiotic vs. placebo) alongside its normal diet for a 3-month period. After a three-week wash out period, the second phase starts by administering the respective other supplement for another 3 months., Discussion: The current study considers modern high-quality standards for epilepsy medication trials. Common biasing effects should be limited to a possible minimum (regression-to-the mean effect, placebo effect, observer effect), ensuring a high validity and accuracy of the acquired results, thus enabling a representative nature of the efficacy of Bifidobacterium longum as add-on supplement for dogs suffering from epilepsy and its comorbidities. This publication should provide a description of the study procedure and data acquisition methods, including prognosed statistical analysis., (© 2023. The Author(s).)

Background: In dogs with a congenital extrahepatic portosystemic shunt (EHPSS), outcome after surgical attenuation is difficult to predict., Objectives: Develop a minimally invasive test to predict outcome after surgical EHPSS attenuation and establish risk factors for postattenuation seizures (PAS)., Animals: Eighty-five client-owned dogs referred for surgical attenuation of a single EHPSS., Methods: mRNA expression of 8 genes was measured in preoperatively collected venous blood samples. Outcome was determined at a median of 92 days (range, 26-208) postoperatively by evaluating clinical performance, blood test results and abdominal ultrasonography. Multivariable logistic regression was used to construct models predicting clinical and complete recovery. The associations between putative predictors and PAS were studied using univariable analyses., Results: Five of 85 dogs developed PAS. Risk factors were age, white blood cell (WBC) count and expression of hepatocyte growth factor activator and LysM and putative peptidoglycan-binding domain-containing protein 2. Clinical recovery was observed in 72 of 85 dogs and complete recovery in 51 of 80 dogs (median follow-up, 92 days). The model predicting clinical recovery included albumin, WBC count, and methionine adenosyltransferase 2 alpha (MAT2α) expression, whereas the model predicting complete recovery included albumin, and connective tissue growth factor precursor and MAT2α expression. The areas under the receiver operating characteristic curves were 0.886 (95% confidence interval [CI]: 0.783, 0.990) and 0.794 (95% CI: 0.686, 0.902), respectively., Conclusions and Clinical Importance: Two models were constructed for predicting outcome after EHPSS attenuation using venous blood samples. The model predicting clinical recovery showed the best diagnostic properties. Clinical application requires further validation., (© 2023 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Objectives: Cerebrospinal fluid (CSF) analysis is used in the diagnostic investigation of cats with epileptic seizures. The aim of this retrospective study was to evaluate the diagnostic value of CSF analysis in cats with epileptic seizures that have unremarkable brain MRI or only hippocampal signal changes., Methods: Unremarkable brain MRI or MRI studies with signal alterations in the hippocampus only in cats with suspected epilepsy and CFS analysis performed at the Small Animal Internal Department or Diagnostic Imaging Department at Vetmeduni Vienna, Austria, between 2011 and 2017 were reviewed. Total nucleated cell count, total protein, blood contamination and cytology data from CSF analysis were evaluated., Results: In total, 87 cats were included. Seventy cats (80.5%) had unremarkable MRI, five (5.7%) had hippocampal signal changes with contrast enhancement and 12 (13.8%) had hippocampal signal changes without contrast enhancement. Overall, four cats (4.6%) had abnormalities on CSF analysis; all (100%) had an increased total nucleated cell count (22 cells/μl, 7 cells/μl, 6 cells/μl and 6 cells/μl, respectively), and no cat had increased total protein (100%), although in one cat total protein was not evaluated. Three of these cats had unremarkable MRI and one had hippocampal signal changes without contrast enhancement. The median duration of epileptic signs prior to the MRI study was 2 days., Conclusions and Relevance: Our results show that, in our cohort of epileptic cats with unremarkable brain MRI or with hippocampal signal changes, CSF analysis was usually normal. This should be considered before performing a CSF tap.

Objectives: Hypertensive encephalopathy in cats is an important entity but is underestimated in clinical practice. This could be explained, in part, by non-specific clinical signs. The objective of this study was to characterise the clinical manifestations of hypertensive encephalopathy in cats., Methods: Cats with systemic hypertension (SHT) recognised by routine screening, associated with underlying predisposing disease or a clinical presentation suggestive of SHT (neurological or non-neurological), were prospectively enrolled over a 2-year period. Confirmation of SHT was based on at least two sets of measurements of systolic blood pressure >160 mmHg by Doppler sphygmomanometry., Results: Fifty-six hypertensive cats with a median age of 16.5 years were identified; 31 had neurological signs. In 16/31 cats, neurological abnormalities were the primary complaint. The other 15 cats were first presented to the medicine or ophthalmology service, and neurological disease was recognised based on the cat's history. The most common neurological signs were ataxia, various manifestations of seizures and altered behaviour. Individual cats also showed paresis, pleurothotonus, cervical ventroflexion, stupor and facial nerve paralysis. In 28/30 cats, retinal lesions were detected. Of these 28 cats, six presented with a primary complaint of visual deficits, and neurological signs were not the primary complaint; nine presented with non-specific medical issues, without suspicion of SHT-induced organ damage; in 13 cats, neurological issues were the primary complaint and fundic abnormalities were detected subsequently., Conclusions and Relevance: SHT is common in older cats and the brain is an important target organ; however, neurological deficits are commonly ignored in cats with SHT. Gait abnormalities, (partial) seizures and even mild behavioural changes should prompt clinicians to consider the presence of SHT. A fundic examination in cats with suspected hypertensive encephalopathy is a sensitive test to support the diagnosis.

Objective: The goal of this study was to compare sleep and seizure frequency between epileptic dogs prescribed a 20% activity increase and epileptic dogs not prescribed an activity increase., Methods: Sixty-nine dogs receiving anti-epileptic drug therapy were enrolled in a 6-month prospective, randomised, placebo-controlled clinical trial with an intention-to-treat analysis. A canine activity monitoring device was used to measure activity levels and sleep scores., Results: Using an intention-to-treat analysis, the treatment group had an average of 0.381 more seizures per month (95% CI: 0.09 to 0.68) compared with the control group, although the difference in seizure days per month was not statistically significant. In a subgroup analysis of dogs whose activity increased by at least 10%, partial compliers had 0.719 more seizures per month (95% CI: 0.22 to 1.22) and 0.581 seizure days per month (95% CI: 0.001 to 1.16) compared with the control group. Sleep scores increased by 1.2% in the treatment compared with the control group (95% CI: 0.2 to 2.3%)., Conclusions: Seizure frequency and sleep score increased slightly, but significantly, in dogs with idiopathic epilepsy prescribed an increase in activity, compared with a control group., (© 2022 The Authors. Journal of Small Animal Practice published by John Wiley & Sons Ltd on behalf of British Small Animal Veterinary Association.)

Transient hypophosphatemia is often detected in humans following generalized tonic-clonic seizures (GTCS), and serum phosphorus concentration (sPi) serves as a marker to differentiate GTCS from syncope. The objective of this retrospective study was to assess the usefulness of hypophosphatemia as a diagnostic marker for GTCS in dogs. Eighty-seven and 26 client-owned dogs with GTCS or syncope, respectively, were enrolled. Dogs were included if the episode occurred ≤ 3 h from presentation, and if sPi and serum creatinine (sCr) were measured. Dogs were excluded if aged < 1 year or if sCr exceeded 176.8 μmol/L. There were no group differences in sCr. Hypophosphatemia (sPi ≤ 0.97 mmol/L) occurred in 28 dogs (32%) in the seizure group, and in no dogs in the syncope group. Median sPi was significantly (P < 0.001) lower in the seizure group (1 mmol/L, [range, 0.31-2.87 mmol/L]) compared to the syncope group (1.35 mmol/L [range, 0.97-2.71 mmol/L]). Furthermore, in dogs presented while seizing (n = 24/87; 28%) median sPi was significantly lower compared to those that were not (0.9 mmol/L [range, 0.3-1.74 mmol/L] vs. 1 mmol/L [range, 0.33-2.18 mmol/L], P = 0.050). ROC analysis of sPi as a marker of GTCS yielded an AUC of 0.757 (95% confidence interval 0.667-0.847), with an optimum cutoff point of 0.97 mmol/L, corresponding to specificity and sensitivity levels of 100% and 44%, respectively. In conclusion, sPi may, in certain cases, serve as an additional diagnostic tool to differentiate GTCS from syncope in dogs. Hypophosphatemia, especially with sPi < 0.97 mmol/L, may be useful in clinical practice to rule in GTCS., Competing Interests: Conflict of interest statement None of the authors has any financial or personal relationships that could inappropriately influence or bias the content of the paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The anticonvulsant effect of cannabidiol (CBD), which has been confirmed by findings from animal models and human trials, has attracted the interest of veterinary practitioners and dog owners. Moreover, social media and public pressure has sparked a renewed awareness of cannabinoids, which have been used for epilepsy since ancient times. Unfortunately, at this moment veterinarians and veterinary neurologists have difficulty prescribing cannabinoids because of the paucity of sound scientific studies. Pharmacokinetic studies in dogs have demonstrated a low oral bioavailability of CBD and a high first-pass effect through the liver. Administering CBD in oil-based formulations and/or with food has been shown to enhance the bioavailability in dogs, rats and humans. Tolerability studies in healthy dogs and dogs with epilepsy have demonstrated that CBD was safe and well tolerated with only mild to moderate adverse effects. In this context, it should be noted that the quality of available CBD varies widely, underscoring the importance of pharmaceutical quality and its control. One clinical trial in dogs with drug-resistant idiopathic epilepsy failed to confirm a difference in response rates between the CBD group and the placebo group, while in another cross-over trial a ≥ 50 % reduction in epileptic seizure frequency was found in six of 14 dogs in the treatment phase, a reduction that was not observed during the placebo phase. Based on the current state of knowledge it is not possible to provide clear-cut recommendations for the use of CBD in canine epilepsy. Randomized controlled canine trials with large sample sizes are needed to determine the range of therapeutic plasma concentrations, develop evidence-based dosing regimens, determine the efficacy of cannabidiol in drug-refractory epilepsy, and explore potential associations between treatment effects and different etiologies, epilepsy types, and drug combinations., Competing Interests: Conflict of interest statement HP has received funding for consulting, talks and research collaborations from Eisai, Zogenix, Elanco, Roche, Lario/Exeed Epidarex, Angelini, Jazz Pharmaceuticals and MSD. SM has received funding for consulting, talks and research collaborations from Applied Basic Science Corporation and Canopy Growth Corporation. AT received funding for research collaborations by Boehringer Ingelheim. The authors have no other financial or personal relationships with other people or organisations that could inappropriately influence or bias the content of the paper., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Feline epilepsy is treated with antiseizure medications, which achieves fair to good seizure control. However, a small subset of feline patients with drug-resistant epilepsy requires alternative therapies. Furthermore, approximately 50 % of cats with epileptic seizures are diagnosed with structural epilepsy with or without hippocampal abnormality and may respond to surgical intervention. The presence of hippocampal pathology and intracranial tumors is a key point to consider for surgical treatment. This review describes feline epilepsy syndrome and epilepsy-related pathology, and discusses the indications for and availability of neurosurgery, including lesionectomy, temporal lobectomy with hippocampectomy, and corpus callosotomy, for cats with different epilepsy types., Competing Interests: Conflict of interest statement None of the authors of this paper has a financial or personal relationship with other people or organizations that could inappropriately influence or bias the content of the paper., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objectives: To investigate how primary care clinicians in the UK approach initial management of canine generalised epileptic seizures, including factors potentially associated with prescription and choice of anti-seizure drugs., Materials and Methods: Electronic health records concerning 3,150,713 consultations (917,373 dogs) were collected from 224 veterinary practices by the Small Animal Veterinary Surveillance Network. Free-text clinical narratives were reviewed to identify those consistent with generalised epileptic seizure activity, including only those recording the first presentation for seizures. Dogs older than 6 years were excluded., Results: Five hundred and seventeen cases were included. Sixty-seven dogs (13.0%) received anti-seizure drugs at first presentation; this was significantly more likely in dogs presented with cluster seizures (odds ratio 13.8, 95% confidence interval 7.3 to 26.1). Phenobarbital (n=36) and imepitoin (n=29) were the most frequently chosen anti-seizure drugs. Presentation for a single epileptic seizure occurred in 321 dogs; seven were prescribed anti-seizure drugs. Eighty-six dogs were presented with cluster seizures; 38 were prescribed anti-seizure drugs, most frequently imepitoin (n= 19) and phenobarbital (n=17). Of the dogs presenting with a single seizure and at least 6-month follow-up (n=165), 33 (20%) did not have subsequent seizures recorded., Clinical Significance: Primary care clinicians rarely prescribed anti-seizure drugs following a single epileptic seizure in accordance with International Veterinary Epilepsy Task Force recommendations. Less than half of dogs initially presenting with cluster seizures were prescribed anti-seizure drugs. Imepitoin was frequently selected in the treatment of cluster seizures despite no authorisation for this purpose. These findings may ultimately contribute to improved cohesion in the management of canine epileptic seizures between primary care and referral institutions., (© 2022 British Small Animal Veterinary Association.)

Background: Focal epileptic motor seizures manifested by limb contraction have been recognized anecdotally in Pomeranians., Objectives: To investigate clinical features of idiopathic epilepsy (IE) and epilepsy of unknown cause (EUC) in Pomeranians as well as the ADAM23 haplotype frequency previously reported as a common risk haplotype for epilepsy in several breeds of dogs., Animals: Twenty-eight Pomeranians, including 15 with IE and 13 with EUC. Nine Pomeranians with epilepsy and 8 control Pomeranians were used for ADAM23 risk haplotype analysis., Methods: Case series study including both retrospectively and prospectively collected cases. The ADAM23 haplotype was determined by direct sequencing of PCR amplicons. Data were analyzed descriptively., Results: Focal epileptic seizures (FS) were the predominant type of seizure in 22 of 28 dogs (78.6%). Among these, 12 of the IE dogs (80.0%) and 10 of the EUC dogs (76.9%) showed FS. Notably, 21 of 22 Pomeranians with FS (95.5%) showed limb contraction during ictal periods. Some dogs with FS also showed immobility, generalized tremors, difficulty walking or moving, autonomic signs, orofacial automatisms or some combination during ictal events. Ten dogs with FS and limb contraction had electroencephalography (EEG) performed, and interictal epileptiform discharges were identified in 9 dogs. The haplotype frequency of ADAM23 in cases was lower (27.8%) than that of the controls (56.3%)., Conclusions and Clinical Importance: In our study, FS was the predominant type of seizure in Pomeranians, and almost all cases with FS showed limb contraction, regardless of whether having IE or EUC., (© 2022 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Objective: To describe new onset of generalized seizures in 3 young dogs following cessation of a benzodiazepine-containing sedation protocol to facilitate mechanical ventilation (MV) for hypoxemia., Series Summary: Three dogs under 5 months of age underwent MV due to severe hypoxemia. All 3 dogs were sedated with a constant rate infusion of benzodiazepines as part of their sedation protocol to facilitate MV. All 3 dogs had an acute onset of generalized seizures within 36 hours of sedation cessation and weaning from MV. All 3 dogs' seizures were successfully managed with a slow, tapering course of benzodiazepines. One dog was additionally treated with levetiracetam at the time of initial seizure activity, which was discontinued 1 year following discharge and absence of ongoing seizure activity. All 3 dogs were discharged successfully with no reports of ongoing seizures or neurologic deficits after discharge., New or Unique Information Provided: Young dogs managed with benzodiazepines to facilitate MV may have acute onset of generalized seizures following cessation, which can be successfully managed with short-term benzodiazepine therapy. The 3 cases in this series demonstrated a positive outcome and were successfully managed following acute onset of generalized seizure activity post-MV., (© 2022 The Authors. Journal of Veterinary Emergency and Critical Care published by Wiley Periodicals LLC on behalf of Veterinary Emergency and Critical Care Society.)