Anticonvulsant effects of desvenlafaxine on modulating brain monoamine and oxidative stress in mice / Efeitos anticonvulsivantes da desvenlafaxina na modulação da monoamina cerebral e do estresse oxidativo em camundongos

Desvenlafaxine succinate (DVS) inhibits serotonin reuptake selectively and is approved for major depressive disorders. This research investigated influence of DVS on modulating brain monoamine and oxidative stress in mice. The antiepileptic potential of DVS (10, 20, or 30 mg/kg/i.p.) in pentylenetetrazole (PTZ; 85 mg/kg) with i.p. route of administration, strychnine (STR; 75 mg/kg) with i.p. route, pilocarpine (400 mg/kg) with s.c. route and maximal electroshock MES-induced convulsion in mouse models. The activities of oxidative stress, i.e. superoxide dismutase (SOD), glutathione (GSH) and lipid peroxidation (LPO) as well as gamma-aminobutyric acid (GABA) in the brains of PTZ-induced convulsive mice. Treatment with DVS increased the latency to develop siezures and declined mortalities in rodents against PTZ, STR and pilocarpine-induced convulsions. Results of MES-leaded siezures revealed that DVS reduced tonic hind limb extension duration and mortalities significantly. Brain, SOD, GSH and GABA level were significantly (P<0.01) increased and LPO reduced significantly (P<0.01) after DVS treatment. Furthermore, the DVS did not show any motor coordination signs in the rotarod test. We demonstrated that the role of DVS in convulsion genesis in mice under control condition and attenuate the PTZ-induced oxidative damage.

O succinato de desvenlafaxina (DVS) inibe seletivamente a recaptação da serotonina e é aprovado para transtornos depressivos maiores. Esta pesquisa investigou a influência do DVS na modulação da monoamina cerebral e do estresse oxidativo em camundongos. O potencial antiepiléptico de DVS (10, 20 ou 30 mg / kg / i.p.) Em pentilenotetrazole (PTZ; 85 mg / kg) com i.p. via de administração, estricnina (STR; 75 mg / kg) com i.p. via, pilocarpina (400 mg / kg) com s.c. rota e convulsão induzida por MES de eletrochoque máximo em modelos de camundongos. As atividades de estresse oxidativo, ou seja, superóxido dismutase (SOD), glutationa (GSH) e peroxidação lipídica (LPO), bem como ácido gama-aminobutírico (GABA) nos cérebros de camundongos convulsivos induzidos por PTZ. O tratamento com DVS aumentou a latência para desenvolver crises e diminuiu a mortalidade em roedores contra convulsões induzidas por PTZ, STR e pilocarpina. Os resultados de siezures conduzidos por MES revelaram que o DVS reduziu significativamente a duração e a mortalidade da extensão tônica dos membros posteriores. Os níveis de cérebro, SOD, GSH e GABA aumentaram significativamente (P < 0,01) e o LPO reduziu significativamente (P < 0,01) após o tratamento com DVS. Além disso, o DVS não apresentou sinais de coordenação motora no teste do rotarod. Demonstramos o papel do DVS na gênese da convulsão em camundongos sob condição de controle e atenua o dano oxidativo induzido por PTZ.

Anticonvulsant effects of desvenlafaxine on modulating brain monoamine and oxidative stress in mice / Efeitos anticonvulsivantes da desvenlafaxina na modulação da monoamina cerebral e do estresse oxidativo em camundongos

Desvenlafaxine succinate (DVS) inhibits serotonin reuptake selectively and is approved for major depressive disorders. This research investigated influence of DVS on modulating brain monoamine and oxidative stress in mice. The antiepileptic potential of DVS (10, 20, or 30 mg/kg/i.p.) in pentylenetetrazole (PTZ; 85 mg/kg) with i.p. route of administration, strychnine (STR; 75 mg/kg) with i.p. route, pilocarpine (400 mg/kg) with s.c. route and maximal electroshock MES-induced convulsion in mouse models. The activities of oxidative stress, i.e. superoxide dismutase (SOD), glutathione (GSH) and lipid peroxidation (LPO) as well as gamma-aminobutyric acid (GABA) in the brains of PTZ-induced convulsive mice. Treatment with DVS increased the latency to develop siezures and declined mortalities in rodents against PTZ, STR and pilocarpine-induced convulsions. Results of MES-leaded siezures revealed that DVS reduced tonic hind limb extension duration and mortalities significantly. Brain, SOD, GSH and GABA level were significantly (P<0.01) increased and LPO reduced significantly (P<0.01) after DVS treatment. Furthermore, the DVS did not show any motor coordination signs in the rotarod test. We demonstrated that the role of DVS in convulsion genesis in mice under control condition and attenuate the PTZ-induced oxidative damage.(AU)

O succinato de desvenlafaxina (DVS) inibe seletivamente a recaptação da serotonina e é aprovado para transtornos depressivos maiores. Esta pesquisa investigou a influência do DVS na modulação da monoamina cerebral e do estresse oxidativo em camundongos. O potencial antiepiléptico de DVS (10, 20 ou 30 mg / kg / i.p.) Em pentilenotetrazole (PTZ; 85 mg / kg) com i.p. via de administração, estricnina (STR; 75 mg / kg) com i.p. via, pilocarpina (400 mg / kg) com s.c. rota e convulsão induzida por MES de eletrochoque máximo em modelos de camundongos. As atividades de estresse oxidativo, ou seja, superóxido dismutase (SOD), glutationa (GSH) e peroxidação lipídica (LPO), bem como ácido gama-aminobutírico (GABA) nos cérebros de camundongos convulsivos induzidos por PTZ. O tratamento com DVS aumentou a latência para desenvolver crises e diminuiu a mortalidade em roedores contra convulsões induzidas por PTZ, STR e pilocarpina. Os resultados de siezures conduzidos por MES revelaram que o DVS reduziu significativamente a duração e a mortalidade da extensão tônica dos membros posteriores. Os níveis de cérebro, SOD, GSH e GABA aumentaram significativamente (P < 0,01) e o LPO reduziu significativamente (P < 0,01) após o tratamento com DVS. Além disso, o DVS não apresentou sinais de coordenação motora no teste do rotarod. Demonstramos o papel do DVS na gênese da convulsão em camundongos sob condição de controle e atenua o dano oxidativo induzido por PTZ.(AU)

Síndrome vestibular secundária à otite média em gata / Secondary vestibular syndrome to otitis media in a cat

A Síndrome Vestibular é um distúrbio frequente na neurologia felina que é caracterizado como um conjunto de sinais neurológicos, causados por uma disfunção de qualquer parte do sistema vestibular. Este é dividido nos componentes periférico e central e o exame neurológico é essencial para localizar a origem da lesão. A Síndrome Vestibular Periférica pode ser causada por anomalias congênitas, neoplasias, traumas, pólipos e doenças inflamatórias; sendo a otite média/interna uma das principais etiopatogenias em cães e gatos. Dessa forma, o presente trabalho tem como objetivo apresentar um relato de caso de um felino, fêmea, sem raça definida, de sete meses de idade, apresentando Síndrome Vestibular secundária à otite média. O animal deu entrada na clínica com sinais neurológicos súbitos, apresentando nistagmo e incoordenação motora, bem como secreção nasal unilateral. Foram solicitados exames hematológicos e bioquímicos, ultrassonografia abdominal e radiografia de crânio, além de recomendada a internação. Nos exames bioquímicos, os valores de bilirrubina total e frações estavam acima do valor de referência e a relação albumina/globulina estava diminuída. O exame radiográfico confirmou a suspeita de otite média. O tratamento foi realizado com marbofloxacino e gabapentina. Após o tratamento, o animal apresentou melhora significativa do quadro clínico. Baseado no exposto, conclui-se que a Síndrome Vestibular secundária à alteração otológica é um quadro presente na rotina veterinária, sendo importante a associação de exame clínico e exames complementares para que seja possível chegar ao diagnóstico.

Vestibular syndrome is a frequent disorder in feline neurology that is characterized as a set of neurological signs caused by a dysfunction of any part of the vestibular system. The vestibular system is divided into peripheral and central components, and a neurological examination is essential to locate the origin of the lesion. The peripheral vestibular syndrome can be caused by congenital anomalies, neoplasms, trauma, polyps, and inflammatory diseases, with otitis media/internal being one of the main etiologies in dogs and cats. Thus, the present work aims to present a case report of a feline, female, mixed breed, seven months old, with secondary vestibular syndrome to otitis media. The animal was admitted to the clinic with sudden neurological signs, presenting nystagmus and motor incoordination, as well as unilateral nasal secretion. Hematological and biochemical tests, abdominal ultrasound, and skull radiography were requested, and hospitalization was recommended. In the biochemical tests, the values of total bilirubin and fractions were above the reference value and the albumin/globulin ratio was decreased. The radiographic examination confirmed the suspicion of otitis media. The treatment was performed with marbofloxacin and gabapentin. After treatment, the animal showed a significant improvement in clinical condition. Therefore, it is concluded that secondary vestibular syndrome to otologic alteration is a condition present in the veterinary routine, and the association of clinical examination and complementary exams is important so that it is possible to reach the diagnosis.

Chemodectoma in a bitch

Background: Chemodectomas, better known as tumors of the base of the heart, arise from aortic bodies, respiratory chemoreceptors located near or inside the aortic arch or originate from receptors located in the carotid arteries. Relatively rare, they affect dogs and, to a lesser extent, cats. They gain great importance when they influence the function of the cardiovascular system, with animals showing clinical signs related to congestive heart failure. Clinical diagnosis is based on symptomatology and complementary tests such as radiography, electrocardiography and echocardiography, while the definitive diagnosis is obtained by cytological and histopathological exams. This study aims to reports a case of malignant chemodectoma in a bitch, whose main symptomatology was neurological and not cardiovascular. Case: A 1-year-old Rottweiler bitch was attended with neurological alterations compatible with vestibular syndrome, hyporexia, dysphagia, apathy, melena, emesis, and purulent nasal discharge on the right nostril. On physical examination, the animal showed depressed level of consciousness, poor body condition, bilateral quemosis, paralysis of the right eye, inspiratory dyspnea and muffling of cardiac auscultation, besides a subcutaneous nodule between the scapulae. On neurological evaluation, horizontal nystagmus, head tilt to the right side, ventromedial strabismus and facial nerve paralysis on the right side were observed so that the localization of the lesion was set in peripheral vestibular system. During anesthesia for esophageal tube placement, a mass from the hard palate to the oropharynx was noted, making endotracheal intubation impossible to perform. Biopsy of this nodule was performed, and tracheostomy was indicated, but the owner opted for euthanasia before the procedure. Necropsy revealed white soft masses in the bilateral retromandibular region, on the subcutaneous tissue near the scapulae, in the right ear and since nasopharynx to the soft palate, in addition to sparse white nodules in the heart, lung, carotid artery, kidneys, right ovary, mesentery near to the spleen, and axillary lymph node. Histologically, the nodules were characterized by neoplastic cells population organized in short bundles or cords, arranged around small blood vessels surrounded by delicate connective tissue. Neoplastic cells infiltrated muscles and blood and lymphatic vessels were filled by multiple neoplastic emboli. The histological pattern of the cells allowed the diagnosis of chemodectoma. Discussion: The bitch from this case had 1-year-old when diagnosed with chemodectoma, differently from most cases from literature, that are between 7 to 15 years old. Furthermore, primarily cardiac tumors are considered rare, being chemodectoma the most common, often reported in Boxer and Boston Terrier dogs, but unusual in Rottweilers. Despites some articles mentioning seizure and Horner's Syndrome secondary to a carotid body chemodectoma, neurological signs are not commonly observed in these cases. The presence of the tumor in the middle ear region of the right side supports the occurrence of peripheral vestibular syndrome and facial nerve paralysis on the same side. Because it is a neoplasm that is usually detected late during the course of the disorder, most patients either cannot obtain diagnosis in vivo, as in this reported animal, which was in such a critical condition that underwent euthanasia, or there are no more possible therapeutic choices. In the patient described, there were numerous metastatic masses and nodules spread throughout the body. Although the typical clinical signs in animals with chemodectomas are often related to heart disease, neurological signs may also be present. This report emphasizes the importance of chemodectoma being included as a differential diagnosis in young dogs and even in breeds such as Rottweiler.

Polymyositis associated with brainstem signs in a dog

Background: Polymyositis is a generalized inflammatory myopathy which can lead to rhabdomyolysis. This affection may have several origins, including degenerative, metabolic, autoimmune, infectious, inflammatory, ischemic, traumatic, by drug use, induced by toxins and also of idiopathic origin. Diagnosis is made with seric dosage, electrodiagnostic tests and muscle biopsy. Lesions in the rostral oblong medulla may affect the central vestibular system, and there may be signs such as opisthotonos, nystagmus, and strabismus. The aim of this report is to describe a case of a mixed breed dog with manifestation of polymyositis associated with brainstem signs of probable idiopathic origin. Case: A 5-year-old mixed breed male dog was attended with opisthotonos episodes for 2 days, and pelvic limbs extension and thoracic limbs flexion that lasted 10 to 20 min at intervals of approximately 1 h. The animal was anorexic and had also presented one episode of emesis. Upon neurological examination, ventromedial strabismus and Horner's syndrome was observed on the right side, besides vertical nystagmus, flaccid tetraparesis and absence of proprioception in the four limbs. Biochemical analyses revealed creatine kinase (CK) increased (2,433.9 UI/L - reference: 1.5-28.4 UI/L), and urinalysis showed dark color and presence of occult blood without, however, erythrocyturia. Electrocardiogram (ECG) showed QS wave and deviation of the electrical axis. Treatment with prednisolone (1 mg/kg, BID), phenobarbital (2 mg/kg, BID), maropitant citrate (1 mg/kg in 2 doses), and crystalloid fluid therapy (50 mL/kg/day) were prescribed. On the 4th day, the dog was more active and feeding without a tube, so it recommended keep the treatment at home. On the 10th day, the animal had proprioception present on the 4 limbs and normorexia. Biochemical analyses and urinalysis showed no alterations, but normochromic normochromic anemia with thrombocytopenia and leukocytosis by neutrophilia showed in blood count exam. PCR to Ehrlichia canis, Hepatozoon sp., and Babesia canis resulted negative. On the 15th day, blood count, biochemical analyses and urinalysis showed no alterations. Neurological examination revealed only positional vertical nystagmus. which remained as a sequel. Discussion: Polymyositis may be accompanied by rhabdomyolysis, characterized by acute muscle necrosis, increased CK and myoglobinuria. The animal had polymyositis of acute onset, with myoglobinuria and elevated CK values, whose presentation included myalgia and muscle weakness. In humans, polymyositis is accompanied by changes in electrocardiographic tracing without clinical alterations. In dogs, the first report that showed cardiac involvement was compatible with myocarditis. The changes in ECG in the present case was attributed to failure in myocardial electrical conduction. The patient also showed signs of brainstem and central vestibular system injuries. Stress myopathy, intoxication, snakebite, infectious, and metabolic diseases were discarded leading to a clinical suspicion as idiopathic origin. Similar to a published case, the patient of this report received symptomatic and supportive treatment, being discharged from the hospital 20 days after the onset of clinical signs. Thus, polymyositis may be accompanied by signs indicative of brainstem injury. Patients with rhabdomyolysis require intense monitoring due to the high risk of developing acute renal failure. Since no causative agent was identified, symptomatic treatment combined with the prevention of possible complications were fundamental for the maintenance of the animal's life.

Meningioma intracraniano em cão - tratamento com radioterapia / Intracranial meningioma in a dog - treatment with radiotherapy

Background: The most common primary brain neoplasm is meningioma. Dolichocephalic breeds are predisposed and there is no sexual predilection. Clinical signs depend on the location and size of the tumor and have a progressive course. Primary treatement includes surgery, radiotherapy or both. This study aimed to describe the treatment of a dog with suspected intracranial meningioma with definitive radiotherapy, which resulted in significant clinical improvement and prolonged survival. Case: A 9-year-old Shetland Shepherd bitch was diagnosed with a head tilt to the left side that progressed over a few weeks. She previously received corticosteroid therapy, which resulted a clinical improvement that worsened after treatment was discontinued. Computed tomography revealed an extra-axial brain mass in the caudal fossa, lateralized to the right, welldelimited, and measuring approximately 1.5 × 1.4 × 1.7 cm, suggestive of intracranial meningioma. The patient was treated with radiotherapy using Cobalt-60 equipment, with 18 daily fractions of 2.5 Gy at a total dose of 45 Gy using parallel and opposite technique fields. A new tomography performed 30 days after treatment showed a remission of 85% of the initial brain mass measuring approximately 0.9 × 1.0 × 0.5 cm, as well as complete resolution of the clinical signs initially presented. After 14 months, the patient presented with signs of lethargy and ataxia and was medicated with hydroxyurea at a dose of 50 mg/kg 3 times a week and corticosteroid therapy. However, the patient's neurological condition deteriorated, and she was subjected to reirradiation using the same protocol used previously, which resulted in clinical improvement and a 54% reduction in tumor volume on magnetic resonance. As a late side effect, only permanent alopecia in the irradiated region was observed. The patient died of disease 330 days after the second course of radiotherapy, with a total survival time of 1087 days. Discussion: Meningiomas are extra-axial neoplasms of the central nervous system that grow inside the dura mater. The literature shows that meningiomas are more common in dolichocephalic races with a mean age of 9 years, which supports our findings. Meningiomas most commonly affect the cortical thalamus and cerebellopontine region in dogs, which are normally associated with vestibular symptoms, as seen in this case. Diencephalic damage can result in vestibular signals since the thalamus functions as a relay station for vestibular afferent stimuli that are relayed to the cerebral cortex. In addition to the vestibular syndrome, common clinical signs associated with meningiomas in dogs include seizures, behavioral changes, and walking in circles, which are frequently misinterpreted due to tumor-induced side effects, such as cerebral edema, obstructive hydrocephalus, and cerebral hernia. Advanced imaging techniques should be used to diagnose intracranial neoplasms. In this case, computed tomography was critical for diagnosis and treatment planning. Meningioma treatment may comprise palliative measures, surgery, and radiotherapy. Radiotherapy as a single treatment can improve the quality of life with a decrease in clinical signs and a median survival time of approximately 250-536 days, as reported in the literature. Hydroxyurea can be a therapeutic option in inoperable cases and for patients with clinical limitations to undergo successive anesthesia during radiotherapy. Its most serious side effect is progressive myelosuppression. It can cause temporary partial tumor remission and improvement in clinical signs. As previously stated, radiotherapy can be an effective primary treatment option for treating intracranial meningiomas in dogs, with significant improvement in neurological clinical signs and mild side effects.

Carcinoma de células escamosas em pálpebra com metástase ocular em um gato doméstico / Squamous cell carcinoma of the eyelid with ocular metastases in a domestic cat

Background: Eye neoplasms are infrequent in felines and usually affect the eyelids. Squamous cell carcinoma (SCC) is a neoplasm that occurs owing to recurrent lesions caused by solar radiation and affects the margins of the ears, eyelids, nose and lips of animals with light-colored coat. The clinical signs consist of ulcerated, crusty lesions that may form masses. The diagnosis is established by means of histopathological analysis, and the prognosis depends on the area affected and tumor infiltration. This work aimed to describe a case of SCC in the eyelid with invasion of the eye and its adnexa in a cat, highlighting clinical aspects and the importance of the anatomopathological examination. Case: A female mixed breed senile cat that had been rescued from the streets was brought in for examination. Dehydration and a low body condition score were observed at the general clinical examination. A physical inspection revealed the presence of an ulcerated periocular lesion on the eyelid; the right eye exhibited increased size and loss of definition of its internal structures. The presence of malodorous cerumen in the right ear canal, a tilted head, and walking in circles to the right were also noted. A dysplastic epithelium along with neutrophilic inflammation was observed at the cytopathological analysis. The treatment instituted consisted of administration of antibacterial and anti-inflammatory drugs, and cleaning of the ear. On the follow-up appointment, 2 days later, the patient's condition had worsened and in spite of the supportive therapy administered, the animal died. An anatomopathological study of the body identified, in addition to the alterations in the eyelid and the eye mentioned above, a traumatic lesion with perforation of the mandibular bone, and presence of a brownish content with caseous consistency in the right ear canal. After visualization of the microscopic alterations, the diagnosis established was squamous cell carcinoma of the eyelid with metastases in the optical nerve and choroid blood vessels. Discussion: Squamous cell carcinoma is one of the most common epithelial neoplasms in felines, and can occur in any region of the face; however, the eyelids and the eyes are less frequently affected, which confirms that the case reported here is uncommon. SCC has a higher incidence in female cats older than 10 years of age with light-colored coat and highly exposed to ultraviolet radiation. The case reported here exhibited these characteristics, as the patient had been rescued from the streets where exposition to sunlight is intense. The clinical presentation was consistent with that described in other works, with ulcerated crusty lesions on the eyelid and the nose. Vestibular syndrome, as inferred from the tilted head and circular gait (walking in circles to the right), could be explained by internal otitis, which was observed at necropsy. The cytological analysis of the eye lesion demonstrated the presence of a neutrophilic inflammatory process along with a dysplastic or immature squamous epithelium, which prompted for therapy using antimicrobial and anti-inflammatory drugs. The definitive diagnosis was established with basis on the histopathological analysis, which revealed a pattern of neoplastic cells arranged in clusters or strands connected to the epidermal surface, and the presence of "keratin pearls" consistent with SCC affecting not only the eyelid and the eye, but also invading the optical nerve and the choroid blood vessels. The prognosis was unfavorable owing to the advanced stage of the tumor and concomitant diseases. Even though the development of SCC in the eyelid is relatively common, the occurrence of metastasis in the eye adnexa is rare in felines. An anatomopathological study was required to establish the diagnosis of SCC as the patient's clinical history data were scarce.

Otite média e interna com extensão para tronco encefálico em buldogue francês / Otitis media and internal with brainstem extension in a French bulldog

Background: Otitis is a frequent condition in dogs, with a multifactorial etiology covering primary causes, predisposing and perpetuating factors. It is characterized by an inflammatory process of structures that make up the auditory system, with prevalence data ranging from 15 to 20%, which can occur in any age group and without sex predisposition. According to the location, it can be classified as uni or bilateral, affecting the outer, middle and / or inner ear, the latter two being associated with neurological changes such as vestibulopathy, facial nerve paresis and Horner's syndrome. The morbidity and mortality of otitis media and internal may increase with delay in diagnosis, resulting in delay in the correct treatment, and the extension to brainstem is described in felines and considered rare in dogs. The present study aims to report an atypical case of otitis media and internal, with extension to the brain parenchyma in a brachycephalic dog. Case: A 3-year-old bitch French Bulldog was seen, weighing 12 kg, with a history of vomiting, apathy, nystagmus, ataxia and acute evolution hemiparesis. As a result of adoption, it was not known about the animal's morbid past. On special physical and clinical examination, depressed mental status, changes in postural reactions, nostril stenosis with unilateral mucopurulent nasal discharge, corneal ulcer, palpebral and labial ptosis, absence of eyelid reflex and spontaneous strabismus were observed, all of these findings observed on the left side of the face. No signs of otitis external to otoscopy were found. The clinical signs found characterize left facial nerve paresis and peripheral and central vestibulopathy. Otitis media / internal and meningoencephalitis were suspected. Hemogram, serum biochemistry (glucose, urea, creatinine, alanine aminotransferase, total proteins, albumin, globulin, alkaline phosphatase, gamma glutamyltransferase, phosphorus, total bilirubin, cholesterol and total calcium), urinalysis, rapid tests for erlichiosis, anaplasms , borreliosis, heartworm, distemper and leishmaniasis, CSF analysis, neurological panel performed by PCR (Polymerase Chain Reaction) that tested the animal for Bartonellosis, Lyme Disease (Borrelia burgdorferi), Blastomyces dermatitidis, Cryptococcus sp., Virus West Nile, Distemper, Toxoplasmosis, Neosporose and Coccidioides sp. using conjunctival swab, whole blood, urine and CSF samples. The samples were negative for all of these tests. As an image exam, brain magnetic resonance was performed. In the latter, otitis media and left internal was observed with extension of the lesion to the brain parenchyma. CSF analysis showed cytological changes compatible with a non-suppurative inflammatory process, mild pleocytosis with predominantly mononuclear leukocyte infiltrate. As a form of treatment, antibiotic therapy and total ablation of the auditory canal with lateral bulectomy were performed, showing good results with reduced clinical symptoms. Discussion: It is concluded that although the diagnosis of otitis media and internal with extension to brainstem is more common in cats, it should be included as a differential for central vestibular disorders in dogs, and that the diagnosis together with early and effective treatment are important, since that the evolution of the infection to the central nervous system represents a risk to the patient.

Outcome of a ceratohyiodectomy in a criollo mare with temporohyoid osteoarthropathy

Background: Temporohyoid osteoarthropathy (THO) is a progressive disease that causes acute onset of peripheral vestibular signs with or without facial paralysis. Ankylosis of temporhyoid joint occurs which predispose to fractures of theinvolved bones and consequently causes the commonly neurological signs observed. Clinical signs vary depending on thestage of the disease and the nerves affected. Surgical treatment is advised to improve survival rates in which the ceratohyoidectomy is currently known as the most advantageous. The aim of the present study is to report a case and outcome ofa ceratohyoidectomy procedure in a Criollo mare presenting THO of the right temporohyoid joint.Case: A 17-year-old Criollo mare was referred to the Equine Clinical Hospital of the Federal University of Pelotas witha 5-day history of facial paralysis on the right side, head tilt and difficulty to chew and swallow. Auricular, palpebraland labial ptosis along with deviation of the lip and nostril to the left were observed. A corneal ulcer was also identifiedin the right eye. Complementary imaging exams (endoscopy of the guttural pouches and radiography of the head) wereperformed and showed thickening of the right stylohyoid bone confirming a diagnosis of THO. Anti-inflammatory andantibiotic therapy were administered and the corneal ulcer was treated with topical antibiotics and autologous serum. Dueto rapid deterioration of clinical signs, the mare was referred to surgery. A ceratohyoidectomty procedure was performedunder general anesthesia. In this procedure, the ceratohyoid bone was disarticulated from the ceratohyoid-basihyoid jointand removed. During the procedure, a branch of the linguofacial vein was accidentally incised causing hemorrhage, thebranch was identified and successfully ligated. Recovery was uneventful. Supportive treatment with anti-inflammatory andantibiotics was continued after surgery and ...

Outcome of a ceratohyiodectomy in a criollo mare with temporohyoid osteoarthropathy

Background: Temporohyoid osteoarthropathy (THO) is a progressive disease that causes acute onset of peripheral vestibular signs with or without facial paralysis. Ankylosis of temporhyoid joint occurs which predispose to fractures of theinvolved bones and consequently causes the commonly neurological signs observed. Clinical signs vary depending on thestage of the disease and the nerves affected. Surgical treatment is advised to improve survival rates in which the ceratohyoidectomy is currently known as the most advantageous. The aim of the present study is to report a case and outcome ofa ceratohyoidectomy procedure in a Criollo mare presenting THO of the right temporohyoid joint.Case: A 17-year-old Criollo mare was referred to the Equine Clinical Hospital of the Federal University of Pelotas witha 5-day history of facial paralysis on the right side, head tilt and difficulty to chew and swallow. Auricular, palpebraland labial ptosis along with deviation of the lip and nostril to the left were observed. A corneal ulcer was also identifiedin the right eye. Complementary imaging exams (endoscopy of the guttural pouches and radiography of the head) wereperformed and showed thickening of the right stylohyoid bone confirming a diagnosis of THO. Anti-inflammatory andantibiotic therapy were administered and the corneal ulcer was treated with topical antibiotics and autologous serum. Dueto rapid deterioration of clinical signs, the mare was referred to surgery. A ceratohyoidectomty procedure was performedunder general anesthesia. In this procedure, the ceratohyoid bone was disarticulated from the ceratohyoid-basihyoid jointand removed. During the procedure, a branch of the linguofacial vein was accidentally incised causing hemorrhage, thebranch was identified and successfully ligated. Recovery was uneventful. Supportive treatment with anti-inflammatory andantibiotics was continued after surgery and ...(AU)

Encefalitozoonose em coelho (Oryctolagus cuniculus) / Encephalitozoonosis in rabbit (Oryctolagus cuniculus)

Background: Encephalitozoonosis is caused by the protozoan Encephalitozoon cuniculi, in rabbits, and can affect humans. The disease can be fatal and difficult to diagnose. It can be asymptomatic or cause vestibular neurological disease, paralysis, uveitis in addition to chronic kidney disease in rabbits. The transmission of the microorganism's spores occurs by ingestion, inhalation, or by the transplacental route. The aim of this work is to report a case of encephalitozoonosis in a pet rabbit (Oryctolagus cuniculus). Case: An Oryctolagus cuniculus with a history of paraparesis of the thoracic and pelvic limbs was referred for necropsy, the evolution of the clinical picture happened in one day. After death, a necropsy was performed. Organ fragments were collected, fixed, and processed routinely for histology. Macroscopically, there was evidence of hepatic lobes, without injury to the other organs. Microscopically it was observed in the white and gray substance of the telencephalon multiple circumscribed granulomas composed of a necrotic center surrounded by macrophages, giant multinucleated cells in addition to lymphocytes and plasmocytes in the periphery, delimited by fibrous connective tissue. Around the vessels, perivascular cuffs with 2 to 4 layers of lymphocytic infiltrate were observed. Besides, special staining of Schiff's Periodic Acid (PAS) and Ziehl-Neelsen was performed, in which numerous cylindrical, eosinophilic structures of approximately 2.5 x 1.0 µm were observed, compatible with E. cuniculi spores. Besides, histiocytic lymphoblasts pericoronitis was noted in the liver. There were no relevant changes in the kidney. Discussion: The diagnosis of encephalitozoonosis in rabbits was based on clinical and anatomopathological findings. Tetraparesis was the predominant sign in the present case and was justified by telencephalic lesions. This clinical sign is included in the literature but is less common than the syndrome such as head tilt and paralysis. The diagnosis of the disease is usually made by post mortem examination when it is possible to identify the spores in the lesions. Multifocal granulomatous encephalitis was the most significant finding in this case, which is also consistent with other studies. The pathogenesis of granulomatous lesions is still controversial. It is known that spores allow phagocytosis by macrophages, which induce the production of interleukins and other cytokines by TCD4 + lymphocytes, thereby activating the action of TCD8 + (cytotoxic) lymphocytes. Natural killer cells, granulocytes, other macrophages, and B lymphocytes are also recruited. Although there is such an inflammatory response, the antibodies produced are not efficient to eliminate the agent from the host organism, however, they contribute to the process of opsonization and consequent phagocytosis, facilitating the destruction of the microsporidium by macrophages. The neurological form was predominant in this case, with no chronic or ocular renal forms, possibly due to the rapid clinical evolution. Special stains were useful for visualizing intralesional spores. Although PAS staining is considered to be of little use, it was relevant in this case. The visualization of the agent made it possible to distinguish differential diagnoses, among them vestibular syndrome secondary to otitis due to pasteurellosis, toxoplasmosis, neoplasms, traumas, or diseases of the spine. Thus, a diagnosis of encephalitozoonosis was made in a rabbit through clinical and anatomopathological correlation using Ziehl-Neelsen and PAS stains.

Intracranial epidermoid cyst in a cat / Cisto epidermoide intracraniano em um gato

Epidermoid cysts, also known as epidermal and keratin cysts, or congenital cholesteatomas are benign congenital non-neoplastic tumors, rarely observed in the brain of humans and some animal species (dogs, horses, mice, and rats). Histologically, they are composed of laminated, concentrically arranged keratin surrounded by a thin layer of stratified squamous epithelium. We describe a case of intracranial epidermoid cyst in a 6-year-old mixed-breed male cat in southern Brazil. The patient presented central vestibular syndrome. Given the poor prognosis and the fact that it belonged to a shelter with many dogs and cats, the owner requested euthanasia, and a thorough post-mortem examination was conducted immediately after death. The definitive diagnosis was based on histopathological findings. To the best of our knowledge, this is the first report of an intracranial epidermoid cyst in a cat.(AU)

Cisto epidermoide, também denominado cisto epidermal, cisto de queratina ou colesteatoma congênito é um tumor não neoplásico, benigno e congênito raramente encontrado no encéfalo de humanos e de algumas poucas espécies animais (cães, equinos, camundongos e ratos). Histologicamente, esse tumor é composto por queratina laminada concentricamente arranjada e circundada por uma fina parede de epitélio escamoso estratificado. Descreve-se um caso de cisto epidermoide intracraniano em um gato, macho, sem raça definida, de seis anos de idade, no sul do Brasil. O paciente foi encaminhado para atendimento veterinário por apresentar sinais de síndrome vestibular central. Devido ao mau prognóstico e por pertencer a um abrigo com muitos cães e gatos, o proprietário optou pela eutanásia e o paciente foi encaminhado para a realização de necropsia. O diagnóstico definitivo foi baseado nos achados histopatológicos. Pelo conhecimento dos autores, este é o primeiro relato de um cisto epidermoide intracraniano em um gato.(AU)

Infestation por Rhabditis spp: una revisión / Infestations by Rhabditis spp: a review / Infestações por Rhabditis spp: uma revisão

Os nematoides do gênero Rhabditis são responsáveis por causar a otite parasitária em bovinos leiteiros da raça Gir. Esta afecção parasitária tem sido relatada em vários países de clima quente e úmido. No Brasil, a rhabditiose tem sido descrita em diversas regiões, sendo responsável pela queda na produção de leite nos rebanhos afetados. De acordo com a literatura, a otite parasitária gera danos diretos na economia e sanidade animal, contudo, existe uma certa discrepância no controle e terapêutica utilizados. O objetivo dessa revisão foi proporcionar a comunidade científica, técnicos e aos produtores rurais uma atualização do conhecimento da problemática da otite parasitária no Brasil e no mundo. O controle parasitário do Rhabditis spp., bem como a sua terapêutica ainda são considerados ineficazes, visto que as recidivas são comuns. Dessa forma, a problemática da otite parasitária no Brasil ainda carece de novos estudos, mas alguns protocolos alternativos experimentais recentes apontam sinergicamente para um “horizonte” mais produtivo no controle desta parasitose.

Nematodes of the genus Rhabditis are responsible for parasitic otitis in Gir dairy cattle. This parasitic condition has been reported in several countries with hot and humid climates. In Brazil, it has been described in several regions, being responsible for the drop in milk production in the affected herds. To the best of our knowledge, parasitic otitis causes direct damage to the economy and animal health, however it still lacks a standardized and effective protocol for treatment and control. The purpose of this review was to provide the scientific community, technicians and rural producers with an update on the knowledge of the problem of parasitic otitis in Brazil and worldwide. Parasitic control of Rhabditis spp., as well as its treatment, are still considered ineffective, since recurrences are common. Thus, the problem of parasitic otitis in Brazil requires further studies, but some recent experimental alternative protocols point synergistically towards a more promising “horizon” in the control of this parasitosis.

Los nematodos del género Rhabditis son responsables de causar otitis parasitaria en el ganado lechero de raza Gyr. Esta condición parasitaria se ha informado en varios países con climas cálidos y húmedos. En Brasil, la otitis parasitaria por Rhabditis spp., se ha descrito en varias regiones, siendo responsable de la caída en la producción de leche en los rebaños afectados. Según nuestro conocimiento literario, la otitis parasitaria causa daño directo a la economía y la salud animal, sin embargo, hubo una cierta discrepancia en el control y el tratamiento utilizado. El objetivo de esta revisión fue proporcionarle a la comunidad científica, técnicos y productores rurales una actualización sobre el conocimiento del problema de la otitis parasitaria en Brasil y en todo el mundo. El control parasitario de Rhabditis spp., como también su tratamiento, todavía se consideran ineficaces, ya que las recurrencias son comunes. Por lo tanto, el problema de la otitis parasitaria en Brasil todavía necesita más estudios, pero algunos protocolos alternativos experimentales recientes apuntan sinérgicamente hacia un "horizonte" más productivo en el control de esta parasitosis.

Infestation por Rhabditis spp: una revisión / Infestations by Rhabditis spp: a review / Infestações por Rhabditis spp: uma revisão

Os nematoides do gênero Rhabditis são responsáveis por causar a otite parasitária em bovinos leiteiros da raça Gir. Esta afecção parasitária tem sido relatada em vários países de clima quente e úmido. No Brasil, a rhabditiose tem sido descrita em diversas regiões, sendo responsável pela queda na produção de leite nos rebanhos afetados. De acordo com a literatura, a otite parasitária gera danos diretos na economia e sanidade animal, contudo, existe uma certa discrepância no controle e terapêutica utilizados. O objetivo dessa revisão foi proporcionar a comunidade científica, técnicos e aos produtores rurais uma atualização do conhecimento da problemática da otite parasitária no Brasil e no mundo. O controle parasitário do Rhabditis spp., bem como a sua terapêutica ainda são considerados ineficazes, visto que as recidivas são comuns. Dessa forma, a problemática da otite parasitária no Brasil ainda carece de novos estudos, mas alguns protocolos alternativos experimentais recentes apontam sinergicamente para um “horizonte” mais produtivo no controle desta parasitose.(AU)

Nematodes of the genus Rhabditis are responsible for parasitic otitis in Gir dairy cattle. This parasitic condition has been reported in several countries with hot and humid climates. In Brazil, it has been described in several regions, being responsible for the drop in milk production in the affected herds. To the best of our knowledge, parasitic otitis causes direct damage to the economy and animal health, however it still lacks a standardized and effective protocol for treatment and control. The purpose of this review was to provide the scientific community, technicians and rural producers with an update on the knowledge of the problem of parasitic otitis in Brazil and worldwide. Parasitic control of Rhabditis spp., as well as its treatment, are still considered ineffective, since recurrences are common. Thus, the problem of parasitic otitis in Brazil requires further studies, but some recent experimental alternative protocols point synergistically towards a more promising “horizon” in the control of this parasitosis.(AU)

Los nematodos del género Rhabditis son responsables de causar otitis parasitaria en el ganado lechero de raza Gyr. Esta condición parasitaria se ha informado en varios países con climas cálidos y húmedos. En Brasil, la otitis parasitaria por Rhabditis spp., se ha descrito en varias regiones, siendo responsable de la caída en la producción de leche en los rebaños afectados. Según nuestro conocimiento literario, la otitis parasitaria causa daño directo a la economía y la salud animal, sin embargo, hubo una cierta discrepancia en el control y el tratamiento utilizado. El objetivo de esta revisión fue proporcionarle a la comunidad científica, técnicos y productores rurales una actualización sobre el conocimiento del problema de la otitis parasitaria en Brasil y en todo el mundo. El control parasitario de Rhabditis spp., como también su tratamiento, todavía se consideran ineficaces, ya que las recurrencias son comunes. Por lo tanto, el problema de la otitis parasitaria en Brasil todavía necesita más estudios, pero algunos protocolos alternativos experimentales recientes apuntan sinérgicamente hacia un "horizonte" más productivo en el control de esta parasitosis.(AU)

C-Fos expression in epileptogenic areas of nephropathic rats undergoing star fruit poisoning

Purpose Studies have demonstrated that star fruit consumption by nephropathic patients triggers severe neurotoxic effects that can lead to convulsions or even death. Brain areas likely susceptible to star fruit poisoning have not been investigated. The objective of the present study was to map possible epileptogenic areas susceptible to star fruit intoxication in nephropathic rats. Methods The study analyzed 25 rats (5 groups). Rats in the experimental group underwent bilateral ureteral obstruction surgery and orogastric gavages with star fruit juice. An electroencephalogram was used to confirm convulsive seizures. Urea and creatinine levels were used to confirm the uremia model. Immunohistochemical analysis was used to map cells with c-Fos protein (c-Fos+ cells) to identify brain areas with increased neuronal activity. Control groups included non-nephropathic and nephropathic rats that did not receive star fruit. Results A statistically significant increase (p 0.01) in c-Fos+ cells was noted in nephropathic animals receiving star fruit juice compared to control groups, in brain areas commonly related to epileptogenic neural circuits including the hippocampus, amygdala, rhinal cortex, anterior cingulate area, piriform area, and medial dorsal thalamus. Conclusion These data corroborate the neurotoxic capacity of star fruit in nephropathic patients.(AU)

Tremor de cabeça idiopático (head bobbing) em cão: relato de caso / Idiopathic head tremor in a dog (head bobbing): case report

O tremor de cabeça idiopático, também conhecido como tremor de cabeça episódico, ou head bobbing se trata de distúrbio paroxístico de base hereditária, sendo considerado uma condição benigna que se manifesta com tremores descontrolados da cabeça, de início e término espontâneos. Este relato apresenta um caso de head bobbing em um bulldog francês fêmea de 1 ano e 7 meses. A paciente apresentava histórico de tremor restrito à região de cabeça, principalmente quando estava em repouso, e durante os episódios se mantinha consciente e responsiva a estímulos externos. Os exames clínico geral e neurológico foram realizados e não evidenciaram nenhuma alteração aparente. Hemograma e exames bioquímicos não apresentaram alterações significativas. Foi realizada também a coleta de líquido cefalorraquidiano (LCR), que estava dentro dos parâmetros normais. O diagnóstico clínico foi obtido por meio do histórico, raça, idade, ausência de outros sinais clínicos associados e descartando outras possíveis causas de tremores.

The idiopathic head tremor, also known as episodic head tremor, or head bobbing is an inherited paroxysmal disorder and is considered a benign condition manifested by spontaneous uncontrolled tremors. This report presents a head bobbing in a 1 year and 7 months old female French Bulldog. The patient had a history of tremor restrict to the head region, especially when at rest, during episodes remained conscious and responsive to external stimulation. General clinical and neurological examination were performed and showed no apparent alteration. Blood count and biochemistry evidenced no significant changes. CSF collection was also performed, which was within normal parameters. The clinical diagnosis was obtained by history, race, age, absence of others clinical signs and ruling out other possible causes of tremors.

Tremor de cabeça idiopático (head bobbing) em cão: relato de caso / Idiopathic head tremor in a dog (head bobbing): case report

O tremor de cabeça idiopático, também conhecido como tremor de cabeça episódico, ou head bobbing se trata de distúrbio paroxístico de base hereditária, sendo considerado uma condição benigna que se manifesta com tremores descontrolados da cabeça, de início e término espontâneos. Este relato apresenta um caso de head bobbing em um bulldog francês fêmea de 1 ano e 7 meses. A paciente apresentava histórico de tremor restrito à região de cabeça, principalmente quando estava em repouso, e durante os episódios se mantinha consciente e responsiva a estímulos externos. Os exames clínico geral e neurológico foram realizados e não evidenciaram nenhuma alteração aparente. Hemograma e exames bioquímicos não apresentaram alterações significativas. Foi realizada também a coleta de líquido cefalorraquidiano (LCR), que estava dentro dos parâmetros normais. O diagnóstico clínico foi obtido por meio do histórico, raça, idade, ausência de outros sinais clínicos associados e descartando outras possíveis causas de tremores.(AU)

The idiopathic head tremor, also known as episodic head tremor, or head bobbing is an inherited paroxysmal disorder and is considered a benign condition manifested by spontaneous uncontrolled tremors. This report presents a head bobbing in a 1 year and 7 months old female French Bulldog. The patient had a history of tremor restrict to the head region, especially when at rest, during episodes remained conscious and responsive to external stimulation. General clinical and neurological examination were performed and showed no apparent alteration. Blood count and biochemistry evidenced no significant changes. CSF collection was also performed, which was within normal parameters. The clinical diagnosis was obtained by history, race, age, absence of others clinical signs and ruling out other possible causes of tremors.(AU)

Tremor de cabeça idiopático em cães - relato de dois casos / Idiopathic head tremor in dogs - two case reports

Tremor de cabeça idiopático é uma forma de discinesia paroxística reconhecida como hereditária e associada a determinadas raças, sendo relatado, sobretudo, em Buldogue Inglês, Dobermann Pinscher e Boxer. Conhecido também como head bobbing ou tremor de cabeça episódico, os cães acometidos apresentam crises caracterizadas por tremores limitados à região de cabeça, de direção horizontal, vertical ou ambos, sendo geralmente relacionados a um evento desencadeante. Foram atendidos, no Hospital Veterinário da UFMS, dois caninos da raça Buldogue Inglês (um macho de um ano e uma fêmea de sete meses) com histórico de tremores episódicos restritos à região de cabeça. Exames físicos e neurológicos completos foram realizados, não sendo constatada qualquer alteração. Com base na raça, no histórico, na ausência de outros sinais clínicos e na exclusão de outras causas de tremores, foi dado o diagnóstico de head bobbing. Tal enfermidade caracteriza-se por tremores restritos à região de cabeça, associados a uma condição genética benigna. Não é considerada uma forma de convulsão, uma vez que o animal permanece alerta e responsivo aos estímulos ambientais, os tremores podem ser interrompidos por distrações ou qualquer interação com o ambiente, não sendo responsivos à terapia com anticonvulsivantes. De acordo com a revisão de literatura realizada, estes são os primeiros casos diagnosticados e relatados no Brasil.(AU)

Idiopathic head tremor is a form of paroxysmal dyskinesia recognized as hereditary or associated with certain races, being reported in English bulldogs, doberman pinschers, and boxers. Also known as head bobbing or episodic head tremor, the affected dogs present with seizures characterized by tremors limited to head region, horizontal direction, vertical or both and are usually related to a triggering event. Two dogs of the English bulldog breed (a male of 1 year and a female of 7 months) with a history of episodic tremors restricted to the head region were seen at the UFMS Veterinary Hospital. Complete physical and neurological examinations were performed, and no alterations were found. Based on race, history, absence of other clinical signs and exclusion of other causes of tremors, the diagnosis of head bobbing was performed. Such a disease is characterized by tremors restricted to the head region, associated with a benign genetic condition. It is not considered a form of seizure, since the animal remains alert and responsive to environmental stimuli, the tremors can be interrupted by distractions or any interaction with the environment, being not responsive to anticonvulsant therapy. According to the literature review, these are the first cases diagnosed and reported in Brazil.(AU)

Tremor de cabeça idiopático em cães - relato de dois casos / Idiopathic head tremor in dogs - two case reports

Tremor de cabeça idiopático é uma forma de discinesia paroxística reconhecida como hereditária e associada a determinadas raças, sendo relatado, sobretudo, em Buldogue Inglês, Dobermann Pinscher e Boxer. Conhecido também como head bobbing ou tremor de cabeça episódico, os cães acometidos apresentam crises caracterizadas por tremores limitados à região de cabeça, de direção horizontal, vertical ou ambos, sendo geralmente relacionados a um evento desencadeante. Foram atendidos, no Hospital Veterinário da UFMS, dois caninos da raça Buldogue Inglês (um macho de um ano e uma fêmea de sete meses) com histórico de tremores episódicos restritos à região de cabeça. Exames físicos e neurológicos completos foram realizados, não sendo constatada qualquer alteração. Com base na raça, no histórico, na ausência de outros sinais clínicos e na exclusão de outras causas de tremores, foi dado o diagnóstico de head bobbing. Tal enfermidade caracteriza-se por tremores restritos à região de cabeça, associados a uma condição genética benigna. Não é considerada uma forma de convulsão, uma vez que o animal permanece alerta e responsivo aos estímulos ambientais, os tremores podem ser interrompidos por distrações ou qualquer interação com o ambiente, não sendo responsivos à terapia com anticonvulsivantes. De acordo com a revisão de literatura realizada, estes são os primeiros casos diagnosticados e relatados no Brasil.(AU)

Idiopathic head tremor is a form of paroxysmal dyskinesia recognized as hereditary or associated with certain races, being reported in English bulldogs, doberman pinschers, and boxers. Also known as head bobbing or episodic head tremor, the affected dogs present with seizures characterized by tremors limited to head region, horizontal direction, vertical or both and are usually related to a triggering event. Two dogs of the English bulldog breed (a male of 1 year and a female of 7 months) with a history of episodic tremors restricted to the head region were seen at the UFMS Veterinary Hospital. Complete physical and neurological examinations were performed, and no alterations were found. Based on race, history, absence of other clinical signs and exclusion of other causes of tremors, the diagnosis of head bobbing was performed. Such a disease is characterized by tremors restricted to the head region, associated with a benign genetic condition. It is not considered a form of seizure, since the animal remains alert and responsive to environmental stimuli, the tremors can be interrupted by distractions or any interaction with the environment, being not responsive to anticonvulsant therapy. According to the literature review, these are the first cases diagnosed and reported in Brazil.(AU)

Doença vestibular central por infarto isquêmico secundário a hipotireoidismo em cão / Central vestibular disease due to ischemic stroke secondary to hypothyroidism in a dog

Background: Hypothyroidism in dogs can cause lethargy, weight gain, dermatological signs and, uncommonly, neurological signs. These may involve the peripheral or central nervous system, leading to a decreased level of consciousness, central or peripheral vestibular disease, epileptic seizures, cognitive dysfunction, facial nerve paralysis, laryngeal paralysis, and polyneuropathy. There are few cases reported in the literature relating hypothyroidism and central vestibular disease. The aim of this study was to report a case of a stroke secondary to hypothyroidism that resulted in central vestibular syndrome in a dog. Case: A 13-year-old female Pitbull, weighting 37 kg, was referred to a Veterinary University Hospital with a two weeks history of dyspnea, coughing and walking difficulty. On neurological examination, the animal presented vertical nystagmus, somnolence, non-ambulatory tetraparesis, decreased postural reaction in all limbs and normal spinal reflexes. The laboratory exams revealed a mild leukocytosis and increased creatinine, glucose, cholesterol and triglycerides levels. Due to historical, clinical, neurological and laboratory tests findings, the animal was diagnosed with central vestibular syndrome secondary to an intracranial neoplasm. Clinical treatment was instituted with corticosteroids, however the animal did not respond and died. On necropsy, the heart was enlarged and coronary arteries were thicker. No macroscopic changes were found in the brain. On histological analysis, the coronary arteries were congest by lipids that almost occluded the arterial lumen. The same alteration were found in splenic and renal arterioles, and in the brain’s leptomeninges. Also in the brain, it was observed perivascular infiltration of mononuclear cells and focal gliosis. The thyroid was atrophied and fibrosed bilaterally. Therefore, those changes were compatible with atherosclerosis secondary to hypothyroidism...