The pharmacokinetics of single oral dose extended-release topiramate and adverse effects after multi-dose administration in healthy cats.

Current treatment options for feline epilepsy are limited to medications that require administration of multiple doses per day or administration of a capsule or large tablet. Expanding the current treatment options could improve patient and owner compliance and optimize seizure control. Topiramate has been used sparingly in veterinary medicine, and limited pharmacokinetic studies have focused on immediate release formulations in dogs. If effective and safe, topiramate extended-release (XR) could broaden the current treatment options for feline epilepsy. The aims of this two-phase study were to establish single-dose pharmacokinetics for topiramate XR in cats, identify a dosing regimen that maintains steady-state plasma drug concentrations within a reference range extrapolated from human medicine (5-20 µg/mL), and evaluate the safety of topiramate XR in cats following multidose administration. Topiramate XR administered orally at 10 mg/kg once daily for 30 days was sufficient to achieve the desired concentrations in all cats. While no clinically apparent adverse effects were observed, four out of eight cats developed subclinical anemia, calling into question the safety of topiramate XR with chronic administration. Further studies are necessary to better understand the potential adverse effects and overall efficacy of topiramate XR for the treatment of feline epilepsy.

Canine brucellosis in three littermates, case report.

Three adult littermates were diagnosed with Brucella canis, two of which were diagnosed with discospondylitis. The first littermate, a 2-year-old spayed-female Labrador Retriever, was evaluated for progressive episodes of cervical pain, lethargy, reported circling to the right, and a right-sided head tilt. Magnetic resonance imaging (MRI) of the cervical spine revealed changes consistent with discospondylitis at C6-C7. MRI of the brain was unremarkable and cerebrospinal fluid analysis was declined. Brucella spp. was isolated from aerobic and Brucella blood cultures. PCR performed on the isolate identified Brucella canis and indirect fluorescent antibody (IFA) testing for Brucella canis also confirmed the species. Patient #1 was treated with doxycycline and marbofloxacin for 1 year. Clinical signs returned 2-years after diagnosis. Following the diagnosis of patient #1, a known littermate (patient #2) was tested for Brucella canis. Patient #2 was 2 years old and asymptomatic at the time of diagnosis. Aerobic and Brucella spp. cultures, PCR, and IFA were obtained and were diagnostic for Brucella canis. A 6-month course of marbofloxacin and doxycycline was implemented. The patient remained PCR positive following 4 months of treatment and repeat cultures were planned following 6 months of treatment; however, the patient was lost to follow-up. A third littermate (patient #3) was identified by the family of patient #1. Patient #3 was evaluated at 18 months of age for a 6-month history of progressive lumbosacral pain. Spinal radiographs revealed discospondylitis of the C3-C4, T12-T13, and L7-S1 vertebral endplates. Computed tomography (CT) of the lumbosacral spine was also consistent with discospondylitis at L7-S1. Brucella canis serologic testing consisting of rapid slide agglutination test, 2ME-rapid slide agglutination test, and cytoplasmic agar gel immunodiffusion was positive. Enrofloxacin was administered for 7 months and was discontinued thereafter based on radiographic evidence of healing and resolution of clinical signs. Although Brucella canis is not a rare disease in dogs, the documentation of two out of three adult littermates with associated discospondylitis is an interesting feature. In addition, this report highlights available diagnostic and treatment options, as each patient was managed differently based on clinical signs and the preference of the managing clinician.

Imaging and clinical features of a true gastrogastric intussusception in a dog.

An 18-month-old male mixed breed dog was evaluated for acute vomiting and hematemesis. Clinical signs and initial radiographic findings shared commonalities with reported cases of pylorogastric intussusception in dogs. However, unlike previously reported cases, additional imaging [including ultrasound and computed tomography (CT)] revealed invagination of the gastric fundus into the gastric body, consistent with true gastrogastric intussusception. These findings were confirmed with histopathology and on necropsy. Key clinical message: Although extremely rare, gastrogastric intussusception should be included as a differential diagnosis for any patient presenting with acute vomiting, abdominal pain, dehydration, or tachycardia in combination with the diagnostic imaging findings described in this report.

Caractéristiques cliniques et d'imagerie d'une intussusception gastro-gastrique vraie chez un chien. Un chien mâle de race croisée âgé de 18 mois fut évalué pour des vomissements aigus et de l'hématémèse. Les signes cliniques et les trouvailles radiographiques initiales partageaient des similarités avec des cas rapportés d'intussusception pyloro-gastrique chez des chiens. Toutefois, contrairement aux cas rapportés précédemment, des examens d'imagerie supplémentaires [incluant l'échographie et la tomodensitométrie (CT)] ont révélé une invagination du fundus gastrique dans le corps de l'estomac, compatible avec une intussusception gastro-gastrique vraie. Ces données furent confirmées lors de l'examen histopathologique et de la nécropsie.Message clinique clé :Bien qu'extrêmement rare, l'intussusception gastro-gastrique devrait être incluse dans le diagnostic différentiel pour tout patient présenté avec des vomissements aigus, de la douleur abdominale, de la déshydratation ou de la tachycardie en combinaison avec les trouvailles en imagerie diagnostique décrites dans le présent rapport.(Traduit par Dr Serge Messier).