Meningoencephalitis of unknown origin in dogs

Background: Meningoencephalitis of unknown origin (MUO) is a critical cause of neurological disorders in dogs, mainly affecting small young individuals. Its symptomatology is varied and depends on the affected neuroanatomic region. The ante mortem diagnosis of this condition is uncertain, being achieved by discarding other conditions and often occurring definitively only by performing a necropsy. Thus, this study aims to report 2 cases of meningoencephalitis, one necrotizing and the other granulomatous in dogs. Cases: Case 1. A 3-year-old, Shih Tzu bitch with a body weight of 4 kg, showing proprioceptive ataxia, behavior of walking in circles, and evolving rapidly to non-ambulatory paresis, was treated. The neurological examination showed a posture of decerebrate stiffness and absence of withdrawal reflex and proprioception, suggesting brainstem injury. Laboratory tests showed mild neutrophilia and lymphopenia, while the rapid test for distemper was non-reactive. The cerebrospinal fluid (CSF) analysis showed lymphocytic pleocytosis, and the PCR tests of the CSF, blood, and urine for the detection of infectious diseases were negative, as well as the culture. With no improvement in clinical condition and exams showing a progressive degenerative condition unresponsive to available treatments, the tutor opted for euthanasia of the patient. The subsequently requested necropsy confirmed the diagnosis of granulomatous meningoencephalitis. Case 2. This case refers to a 1-year-and-5-month-old male Maltese breed weighing 4.8 kg. This animal presented walking in circles behavior and loss of vision for a week, with signs worsening rapidly. In the neurological evaluation, the patient presented sensitivity in the middle ear, difficulty opening the mouth, hearing deficit in the right ear, blindness in the right eye, a proprioceptive deficit in the right anterior limb, and head pressing. Laboratory tests showed nonregenerative anemia and mild lymphopenia. After 1 day of hospitalization, the patient showed worsening clinical condition, with obstruction, absence of facial and auricular sensitivity, and nasal stimulus. In addition, onset of generalized seizures was observed; therefore, CSF was analyzed, which did not present significant alterations except for detecting reactive lymphocytes. The bacteriological culture of CSF resulted in no bacterial growth. In addition, the same neurological PCR panel performed for the previous patient was negative. After 5 days of intensive care, the patient presented a cardiorespiratory arrest and died. The subsequently requested necropsy confirmed the diagnosis of necrotizing meningoencephalitis. Discussion: The 2 reported cases confirm that MUO should be considered during the differential diagnoses of patients with neurological alterations. It is known that small-breed dogs are predisposed to these diseases. Laboratory tests and medical imaging are crucial for clinical guidance, helping to discard other neurological pathologies, especially those due to bacterial, fungal, and/or viral agents. However, definitive diagnosis of MUO can only be performed through necropsy and histopathological analysis. For the reported cases, CSF analysis, neurological PCR panel for detecting possible infectious agents, and bacterial culture were essential to rule out other possible causes of meningoencephalitis. Unfortunately, MUO includes progressive neurological disorders causing the patient's death.

Non-invasive monitoring of intracranial pressure waveforms using Braincare® BCMM 2000 monitor in dogs with myelopathies undergoing myelography / Monitoramento não invasivo do formato das ondas de pressão intracraniana usando o monitor Braincare® BCMM 2000 em cães com mielopatias submetidos à mielografia

ABSTRACT: Intracranial pressure (ICP) monitoring is considered the gold standard for optimizing the treatment of humans in intensive care units. However, this procedure is not commonly performed in veterinary medicine because of the limitations and complications of the method. There are some new promising non-invasive techniques for monitoring ICP, but they have not been validated in veterinary medicine. This study aimed to correlate the non-invasive intracranial pressure (NI-ICP) waveforms obtained with the BCMM-2000 Brain4care monitor during myelography in dogs with myelopathies undergoing this exam for diagnostic purposes with the waveforms obtained through invasive monitoring of the subarachnoid pressure (SP). The NI-ICP waveform was monitored in six dogs with myelopathies before (M1), during (M2), and after (M3) contrast medium injection into the subarachnoid space. Cerebrospinal fluid (CSF) was collected before contrast injection. The SP waveform was simultaneously monitored in three of the six dogs. Correlations between the two methods were performed using Pearson's coefficient. The analysis of the morphology and amplitude of the waves at each moment was performed, and at M2, an increase in the P2:P1 ratio (p<0.05) was observed in both monitoring methods. In M3, the values were similar to those of M1, demonstrating the return of cerebral compliance. The comparison of the NI-ICP and SP had a positive correlation in those moments (Pearson's coefficient r=0.76; p=0.027). The speed of contrast administration, degree of spinal cord compression, and volume of CSF previously collected may affect P2:P1 and ICP dynamics. The BCMM-2000 Brain4care monitor was effective in detecting changes in ICP dynamics and abnormal pulse waveforms in dogs with meningoencephalitis of unknown origin, vertebral neoplasm and intervertebral disc disease with and without hemorrhagic myelomalacia, suggesting increased ICP induced by myelography.

RESUMO: A monitorização da pressão intracraniana (PIC) é considerada o padrão ouro para otimizar o tratamento de humanos em unidades de terapia intensiva, entretanto, esse procedimento não é comumente realizado na medicina veterinária devido às limitações e complicações do método. Existem algumas técnicas não invasivas promissoras de monitoramento da PIC, mas elas não foram validadas na medicina veterinária. Este estudo teve como objetivo correlacionar os formatos das ondas não invasivas da PIC (NI-PIC), obtidas com o monitor BCMM-2000 Brain4care, antes e após a injeção de meio de contraste no espaço subaracnóideo de cães com mielopatias submetidos à mielografia para fins diagnósticos, com as formas de onda obtidas por meio de monitoração invasiva da pressão subaracnóidea (PS). O formato das ondas NI-PIC foram monitoradas em seis cães com mielopatias antes (M1), durante (M2) e após (M3) injeção de meio de contraste no espaço subaracnóideo. O líquido cefalorraquidiano (LCR) foi coletado antes da injeção de contraste. A forma da onda da PS foi monitorada simultaneamente em três dos seis cães. As correlações entre os dois métodos foram feitas usando o coeficiente de Pearson. Foi realizada a análise da morfologia e amplitude das ondas em cada momento, e em M2 observou-se aumento da relação P2:P1 (p<0,05) em ambos os métodos de monitoramento. Em M3, os valores foram semelhantes aos de M1, demonstrando o retorno da complacência cerebral. A comparação do NI-PIC e PS apresentou correlação positiva nesses momentos (coeficiente de Pearson r=0,76; p=0,027). A velocidade de administração do contraste, o grau de compressão da medula espinhal e o volume de LCR coletado anteriormente podem afetar a dinâmica P2:P1 e PIC. O monitor BCMM-2000 Brain4care foi eficaz na detecção de alterações na dinâmica da PIC e dos formatos das ondas de pulso anormais em cães com meningoencefalite de origem desconhecida, neoplasia vertebral e doença do disco intervertebral com e sem mielomalácia hemorrágica, sugerindo aumento da PIC induzida pela mielografia.

Use of polymethylmethacrylate plaque as a treatment of cranioschisis associated with meningocele in a Girolando heifer: A case report / Uso de placa de polimetilmetacrilato (PMMA) no tratamento de craniosquise associada à meningocele em uma bezerra girolando: relato de caso

Most genetic diseases affect purebred animals and are inherited as recessive genes. Cranioschisis refers to dysraphism, which occurs in the midline of the skull due to failure to close the cranial symphysis, which can lead to herniation of the meninges filled with cerebrospinal fluid (meningocele), where there is usually a projection of the meningeal tissue. Diagnosis is performed based on clinical examination, characteristic anatomopathological data, and complementary imaging tests. The surgical approach for correction of cranioschisis is the only described as a therapeutic solution and is indicated in cases in which the cranial synthesis defect does not allow for brain protrusion and there is only the occurrence of meningocele, in addition to the absence of severe signs of neurological alteration. This paper reports a case of the use of polymethylmethacrylate (PMMA) plaque to treat cranioschisis associated with meningocele in a Girolando heifer. The surgical opening of the frontonasal sacculation allowed draining a total liquid content of 488 mL, inspection, and suture of the envelope membrane. APMMA plaque, molded to the bone surface and anchored in the adjacent soft tissue, was used to cover the evidenced frontonasal bone opening. Despite the unfavorable prognosis of the disease, the cranioplasty surgery for the treatment of cranioschisis associated with meningocele using PMMA plaque obtained satisfactory results relative to the quality and maintenance of this animal's life, evaluated at 19 months postoperatively.(AU)

A maioria das doenças genéticas acometem animais de raça pura e herdados como genes recessivos.Acraniosquise refere-se à disrafia, que acontece na linha média do crânio pelo não fechamento da sínfise craniana, podendo levar a herniação das meninges repletas de líquido cefalorraquidiano (meningocele), onde geralmente existe projeção do tecido meningeal. O diagnóstico é realizado a partir do exame clínico, dados anatomopatológicos característicos e através da realização de exames complementares de imagem. Como solução terapêutica, a abordagem cirúrgica para correção das craniosquises é a única descrita, e é indicada em casos em que o defeito de síntese craniana não permita a protrusão encefálica e exista a ocorrência apenas da meningocele, além da inexistência de sinais graves de alteração neurológica. O artigo relata um caso de uso de placa de polimetilmetacrilato (PMMA) no tratamento de craniosquise associada à meningocele em uma bezerra Girolando. Instituiu-se a abertura cirúrgica da saculação fronto-nasal, permitindo a drenagem de conteúdo líquido total de 488 mL, inspeção e rafia de membrana envoltória. Para recobrimento da abertura óssea fronto-nasal evidenciada, utilizou-se uma placa de polimetilmetacrilato (PMMA), moldada à superfície óssea e ancorada em tecido mole adjacente. Concluiu-se que, apesar do prognóstico desfavorável da enfermidade, a cirurgia de cranioplastia para tratamento de craniosquise associada à meningocele, com a utilização de placa de PMMA, neste caso, obteve resultados satisfatórios em relação a qualidade e manutenção da vida deste animal, avaliando-se em 19 meses pós-operatório.(AU)

Complications after cerebrospinal fluid collection in dogs with brain neoplasm / Complicações após colheita do líquido cerebroespinhal em cães com neoplasma encefálico

Cerebrospinal fluid (CSF) collection in dogs with brain neoplasms (BN) may be associated with complications owing to increased intracranial pressure caused by expansive lesions. Although this procedure has been performed in dogs with BN, no data regarding complications after CSF tap in these animals is available. Thus, this retrospective study aimed to identify the rate and types of complications observed after CSF taps in dogs with BN. Thirty dogs with BN were included in the study. In 83% (25/30) of the cases, clinical recovery after CSF tap was considered normal, and in 17% (5/30) the recovery was abnormal. The main clinical and neurological signs observed in dogs with abnormal clinical recovery were apnea (5/5), absence of pupillary photomotor reflex (3/5), coma (2/5), and stupor (1/5). In 40% (2/5) of the dogs, herniation of the cerebellum through the foramen magnum was observed on necropsy. In conclusion, the rate of complications after CSF taps was 17%, and was characterized by apnea, absent pupillary photomotor reflex, altered level of consciousness, and encephalic herniation.

A colheita do líquido cerebroespinhal (LCE) em cães com neoplasmas encefálicos (NE) pode estar associada a complicações devido ao aumento da pressão intracraniana (PIC), causada pela lesão expansiva. Embora o procedimento seja realizado em cães com NE, não foram encontrados dados referentes às complicações após colheita de LCE nesses pacientes. Sendo assim, o objetivo do presente estudo retrospectivo foi identificar a taxa, bem como os tipos de complicações observadas após a colheita de LCE em cães com neoplasma encefálico. Dos 30 cães com NE incluídos no estudo, em 83% (25/30) dos casos a evolução clínica após a colheita do LCE foi considerada normal e, em 17% (5/30) anormal. Os principais sinais clínicos e neurológicos observados nos cães com evolução clínica anormal foram apneia (5/5), reflexo fotomotor pupilar ausente (3/5), coma (2/5) e estupor (1/5). Em 40% (2/5) foi observado herniação do cerebelo na necropsia. Com base nos resultados encontrados, conclui-se que a taxa de complicações após a colheita de LCE foi baixa (17%) e as alterações encontradas foram apneia, seguido de reflexo fotomotor pupilar ausente, alteração no nível de consciência e herniação encefálica.

An anatomical training model for cerebrospinal liquid collection and myelography in embalmed dog cadavers / Modelo anatômico para treinamento de colheita de líquido cerebroespinhal e mielografia em cadáveres de cães quimicamente preparados

In research and academic activities, guidelines are essential and imperative especially on the use of animals. Alternative methods that do not bring academic or scientific harm should also be sought. This study aimed to develop a training model for the collection of cerebrospinal fluid (CSF) and myelography in the cervical and lumbar regions in cadavers of embalmed dogs, using an alcoholic solution and curing salts for fixation and conservation. The dogs were divided into 4 grups of 8 animal each and stored between 2ºC and 6ºC, for 30, 60, 90, or 120 days. Durotomy was performed to implant two urethral catheters (one in the cranial direction and another in the caudal direction to the spinal cord access site), in the subduraracnoid space. This space was fixed via manual infusion of saline solution with a 20-mL syringe to simulate the presence of the CSF and the positive pressure, while the puncture was made. Four cadavers of each group were randomly selected for the CSF puncture from the atlantooccipital joint and in the lumbar region between L5 and L6, respectively, and four were used for CSF puncture training, in which radiographic contrast (myelography) was injected in the same locations. This model was cost-effective, did not utilize toxic products, and can preserve cadavers for up to 120 days. In this novel anatomical model, a maximum of 15 students can be trained on CSF puncture, allowing cervical and lumbar myelography and at least 30 perforations per cadaver.

É essencial e imperioso ter critério quanto ao uso de animais em pesquisa e atividades de ensino e, consequentemente, buscar métodos alternativos que não causem prejuízo acadêmico ou científico. Para que não ocorra deterioração dos tecidos, a fixação e conservação de peças anatômicas e cadáveres devem ser realizadas. Objetivou-se, com este estudo, desenvolver um modelo anatômico para treinamento de colheita de líquido cerebroespinhal (LCE) e mielografia, nas regiões cervical e lombar. Os cães foram divididos em quatro grupos contendo oito animais cada e armazenados entre 2ºC e 6ºC, por 30, 60, 90 ou 120 dias. Foi realizada durotomia para implantação de duas sondas uretrais, no espaço subaracnóide. A infusão manual de solução fisiológica com seringa de 20 mL foi utilizada para simular a presença do LCE e a pressão positiva, enquanto era feita a punção. Quatro cadáveres de cada grupo foram selecionados para a punção de LCE na articulação atlantooccipital e na região lombar entre L5 e L6, e quatro foram utilizados para o treinamento da punção de LCE e injeção de contraste radiográfico (mielografia). A técnica anatômica empregada possibilitou o desenvolvimento de um modelo visando ao ensino e pesquisa da radiologia em cadáveres de cães quimicamente preparados, a custo baixo e sem utilização de produtos tóxicos, mantidos sob refrigeração por 120 dias. Com isso, um máximo de 15 alunos podem ser treinados em punção do LCR, permitindo mielografia cervical e lombar com 30 perfurações por cadáver.

Clinical and pathological aspects of an outbreak of Streptococcus suis serotype 9 infection in pigs / Aspectos clínicos e patológicos de um surto de infecção por Streptococcus suis sorotipo 9 em suínos

Streptococcus suis is a Gram-positive pathogen that inhabits the upper respiratory tract and can cause severe systemic inflammatory disease in pigs, mainly during the nursery phase. Streptococcus suis is a reemergent pathogen, and outbreaks of its inducing disease represent significant economic losses for the pig industry worldwide. In this study, we described the clinical, pathological, and molecular aspects of an outbreak of S. suis infection with atypically high mortality. The outbreak occurred in nursery farms integrated into a cooperative in the state of Paraná, Brazil. Of the 30 nurseries, 10 were severely affected by the pathogen and had high economic losses. Clinical signs usually started approximately 10 days after weaning and were mainly characterized by acute nervous and locomotor disorders. The mortality of the affected batches usually ranged between 8% and 10%, but in some cases, it reached 18%. Nine piglets were submitted to post mortem examination. Macroscopically, the synovial joints were enlarged and contained fibrinous exudates. In the central nervous system, there was hyperemia of the leptomeningeal vessels associated with deposition of fibrin and purulent exudate in the leptomeninges. In three piglets, there was thickening of the choroid plexus associated with dilation of the lateral ventricles. Microscopic lesions were characterized mainly by fibrinosuppurative inflammation, which involved the synovial membranes, leptomeninges of the brain, and spinal cord. Furthermore, it also affects the choroid plexus, ependyma, nerve roots, and central canal of the spinal cord. S. suis was isolated from the cerebrospinal fluid, meningeal swabs, and/or synovial fluid of 8/9 piglets, and typified as serotype 9 by multiplex PCR.

Streptococcus suis é um patógeno Gram positivo que habita o trato respiratório superior e pode causar doença inflamatória sistêmica grave em suínos, principalmente durante a fase de creche. Streptococcus suis é um patógeno reemergente e surtos representam perdas econômicas significativas a suinocultura mundial. Neste estudo descrevemos os aspectos clínicos, patológicos e moleculares de um surto de infecção por S. suis com mortalidade atipicamente alta. O surto ocorreu em creches integradas a uma cooperativa do estado do Paraná, Brasil. Das 30 creches, 10 foram severamente afetadas pelo patógeno e apresentavam elevadas perdas econômicas. Os sinais clínicos iniciavam em torno de 10 dias após o desmame e eram caracterizados principalmente por sinais clínicos nervosos e locomotores agudos. A mortalidade dos lotes afetados variava entre 8% e 10%, mas em alguns casos ultrapassava 18%. Nove leitões foram submetidos ao exame post mortem. Macroscopicamente, as articulações sinoviais estavam aumentadas e continham exsudato fibrinoso. No sistema nervoso central havia hiperemia dos vasos leptomeníngeos associada a deposição de fibrina e exsudato purulento nas leptomeninges. Em três leitões havia espessamento do plexo coroide associado a dilatação dos ventrículos laterais. As lesões microscópicas eram caracterizadas principalmente por inflamação fibrinossupurativa que envolvia as membranas sinoviais, as leptomeninges do cérebro e medula espinhal. Além disso, também afetava o plexo coroide, epêndima, raízes nervosas e canal central da medula espinhal. S. suis foi isolado do líquido cefalorraquidiano, suabe de meninge e/ou líquido sinovial de 8/9 leitões e tipificado como sorotipo 9 por PCR multiplex.

Compressive lesions in the central nervous system of buffaloes / Lesões compressivas no sistema nervoso central de bubalinos

This study describes, through a retrospective study, the epidemiological and clinical-pathological findings of compression in the central nervous system (CNS) of buffaloes. The study includes observations made in 15 animals from 1998 to 2021 by reviewing the clinical records of animals with compressive injuries of the CNS treated at the Veterinary Hospital of the Veterinary Medicine Institute of the Federal University of Pará. The animals treated with clinical signs compatible with CNS compressive lesions were subjected to general and specific clinical examinations of the nervous system. Blood samples were collected from four animals for complete blood counts, and cerebrospinal fluid (CSF) samples were collected from three animals for physical evaluation. Thirteen animals were necropsied. The age range of the affected animals ranged from four months to 11 years of age, with a greater frequency over age 12 months (80%, 13/15). The most affected vertebral segment was between T3 and L3 (60%, 9/15), followed by brain injury (20%, 3/15), the L4-S2 segment (13.3%, 2/15) and the C1-C5 segment (6.7%, 1/15). The clinical findings varied according to the location of the lesion. The necropsy findings revealed paraypophyseal abscess in the brainstem and vertebral body, subarachnoid hematoma, lymphoma and vertebral fractures. The performance of a thorough clinical examination of the CNS combined with the necropsy findings was important to characterize the clinical picture and to locate the cause and the affected CNS segments in the buffaloes studied. It is important to include CNS compressive lesions among the neurological diseases of buffaloes.

Esse trabalho descreve, através de estudo retrospectivo, os achados epidemiológicos e clínico-patológicos de compressão no sistema nervoso central (SNC) de bubalinos. O estudo compreendeu as observações realizadas em 15 animais, durante os anos de 1998 a 2021, por meio da revisão dos arquivos de fichas clínicas de animais com lesões compressivas no SNC atendidos pelo Hospital Veterinário do Instituto de Medicina Veterinária da Universidade Federal do Pará. Os animais atendidos com sinais clínicos compatíveis com lesões compressivas no SNC foram submetidos a exames clínicos geral e específico do sistema nervoso. Foram coletadas amostras de sangue de quatro animais para realização de hemograma e amostras de líquido cefalorraquidiano (LCR) de três animais para avaliação física. Foram necropsiados 13 animais. A faixa etária dos animais acometidos variou de quatro meses a 11 anos de idade, com maior frequência na faixa acima de 12 meses (80%, 13/15). O segmento vertebral mais acometido foi entre T3-L3 (60%, 9/15), seguida por lesão no encéfalo (20%, 3/15), pelo segmento L4-S2 (13,3%, 2/15) e pelo segmento C1-C5 (6,7%, 1/15). Os achados clínicos variaram de acordo com a localização da lesão. Os achados de necropsia revelaram abscesso parahipofisário, no tronco encefálico e no corpo da vértebra, hematoma subaracnoidea, linfoma e fraturas vertebrais. A realização de um minucioso exame clínico do SNC associado aos achados de necropsia foram importantes para caracterizar o quadro clínico e localizar a causa e os seguimentos acometidos do SNC nos búfalos estudados. Torna-se importante incluir as lesões compressivas do SNC entre as enfermidades neurológicas dos bubalinos.

Compressive lesions in the central nervous system of cattle: a retrospective study of 50 cases in the Amazon biome / Lesões compressivas no sistema nervoso central de bovinos: um estudo retrospectivo de 50 casos no bioma amazônico

The present study gathered epidemiological and clinical-pathological information about cattle with compressive lesions in the central nervous system (CNS). The retrospective study included observations made in 50 cattle from 1998 to 2021 by reviewing the clinical records of animals with compressive lesions in the CNS treated at the Veterinary Hospital of the Veterinary Medicine Institute of the Federal University of Pará. The animals had clinical signs and were subjected to general and specific clinical examination of the nervous system. Blood samples were collected from 13 animals for complete blood counts, and cerebrospinal fluid (CSF) samples were collected from four animals for physical evaluation. Twenty-nine cattle underwent necropsy. The most affected sites were the T3-L3 (46%, 23/50), C1-C5 (22%, 11/50), C6-T2 (14%, 7/50), sacrococcygeal vertebrae, (4%, 2/50), L4-S2 (2%, 1/50), brain (8%, 4/50) and cerebellum (4%, 2/50). The age of the affected cattle ranged from 20 days to 16 years, with a higher occurrence in animals younger than 12 months (56%, 28/50). More Females were affected (58%, 29/50) than males (42%, 21/50). The clinical signs varied according to the location of the lesion and were mainly represented by ataxia, paresis or paralysis of the limbs, inability to stand and walk, postural changes, hyperesthesia in the extremities, and loss of skin sensitivity at the location of the lesion. The necropsy findings revealed changes such as abscesses in the vertebral body; intervertebral space in the medullary canal, pituitary and cerebellum; granuloma in the arch of the vertebra; fractures of the body of the vertebrae; subarachnoid haematoma; congenital bone alteration causing spinal cord compression; and spondylitis. Detailed anamnesis and clinical examination of the CNS, associated with necropsy findings, were important to determine the cause of the disease, correlate with the clinical picture and locate the affected segments of the CNS in the cattle. It is important to include these diseases in the list of differential diagnoses in cattle with nervous symptoms.

O presente trabalho reúne informações epidemiológicas e clínicopatológicas de bovinos com lesões compressivas no sistema nervoso central (SNC). O estudo retrospectivo compreendeu as observações realizadas em 50 bovinos durante os anos de 1998 a 2021, por meio da revisão dos arquivos de fichas clínicas de animais com lesões compressivas no SNC atendidos pelo Hospital Veterinário do Instituto de Medicina Veterinária da Universidade Federal do Pará. Os animais atendidos com sinais clínicos foram submetidos a exame clínico geral e específico do sistema nervoso. Foram coletadas amostras de sangue de 13 animais para realização de hemograma e amostras de líquido cefalorraquidiano de quatro animais para avaliação física. Foram submetidos à necropsia 29 bovinos. Os locais mais acometidos foram as vértebras T3-L3 (46%, 23/50), C1-C5 (22%, 11/50), C6-T2 (14%, 7/50), sacrococcígea (4%, 2/50) e L4-S2 (2%, 1/50); cérebro (8%, 4/50) e cerebelo (4%, 2/50). A idade dos bovinos afetados variou de 20 dias a 16 anos, com maior ocorrência em animais com menos de 12 meses (56%, 28/50). As fêmeas foram mais acometidas (58%, 29/50) do que os machos (42%, 21/50). Os sinais clínicos variaram de acordo com a localização da lesão e foram representados principalmente por ataxia, paresia ou paralisia dos membros, incapacidade de se levantar e de ficar em estação, alterações posturais, hiperestesia nas extremidades, além de perda da sensibilidade cutânea relacionada com a localização da lesão. Os achados de necropsia revelaram alterações como abscessos no corpo vertebral, no espaço intervertebral, no canal medular, para-hipofisário e no cerebelo; granuloma no arco da vértebra, fraturas do corpo das vértebras; hematoma subaracnoide; alteração óssea congênita causando compressão medular e espondilite. Anamnese detalhada e exame clínico do SNC, associados aos achados de necropsia foram importantes para determinar a causa da doença, correlacionar com o quadro clínico e localizar os segmentos acometidos do SNC dos bovinos. Torna-se importante incluir estas enfermidades na lista de diagnósticos diferenciais em bovinos que apresentem sintomatologia nervosa.

Clinical findings of equine leukoencephalomalacia

ABSTRACT: Equine leukoencephalomalacia (LEM) is a disease caused by the ingestion of food, especially corn, contaminated by fumonisin, a Fusarium verticillioides (synonymous with F. moniliforme) metabolite. The clinical signs of brain injuries have an acute onset and rapid evolution. This study aimed to describe the clinical findings in 11 animals diagnosed with LEM, including cerebrospinal fluid (CSF) analysis. Of these animals, 91% (10/11) were horses, and only 9% (1/11) were asinine. The clinical localization of the lesions was 64% (7/10) cerebral, manifested mainly by altered mental state and behavioral disturbance, and 36% (4/11) were brainstem lesions, manifested by incoordination, head tilt, nystagmus, facial hypoalgesia, difficulty in apprehension, chewing, and swallowing food. Postmortem findings revealed that 82% (9/11) of the lesions were in the cerebrum and 18% (2/11) in the brainstem. CSF findings, such as xanthochromia (43%, 3/7), hyperproteinorrachia (50%, 3/6), and pleocytosis (43%, 3/7) were observed. The affected animals showed neurological signs that were compatible with cerebral and/or brainstem injuries. The CSF from animals with LEM may present with xanthochromia, hyperproteinorrachia, and pleocytosis, reinforcing the fact that this disease should be included in the differential diagnosis of encephalomyelopathies.

RESUMO: A leucoencefalomalácia (LEM) é uma enfermidade que acomete equídeos causada pela ingestão de milho e seus derivados e feno contaminados pela micotoxina fumonisina, um metabólito do fungo Fusarium verticillioides (sinônimo para F. moniliforme). Os sinais clínicos apresentam início agudo e evolução rápida e são decorrentes de lesões encefálicas. O objetivo deste estudo é descrever os achados clínicos de 11 equídeos diagnosticados com LEM, incluindo a análise do líquido cefalorraquidiano (LCR). 91% dos animais afetados eram equinos e somente 9% (1/11) era asinino. A localização clínica das lesões era 64% (7/10) cerebrais, manifestadas por alterações no estado mental e comportamento e 36% (4/10) no tronco encefálico, manifestadas por incoordenação, desvio lateral de cabeça, nistagmo, hipoalgesia da face e dificuldade de apreensão, mastigação e deglutição de alimentos. Comparativamente, os achados post mortem revelaram que 82% (9/11) das lesões eram no cérebro e 18% (2/11) no tronco encefálico. Alterações no LCR, tais como xantocromia (43%, 3/7), hiperproteinorraquia (50%, 3/6) e pleocitose (43%, 3/7), foram observadas. Os animais afetados apresentaram sinais clínicos compatíveis com lesões encefálicas e/ou de tronco cerebral. O LCR de animais com LEM pode apresentar xantocromia, hiperproteinorraquia, e pleocitose, reforçando que esta doença deve ser incluída como diagnóstico diferencial de encefalomielites.

Hypomagnesemia in beef cattle

ABSTRACT: Hypomagnesemia is a major cause of death in grazing beef cows in countries of the Southern Hemisphere such as Argentina, Australia and New Zealand. Here we review the literature on hypomagnesemia in beef cattle and describe an outbreak in Uruguay. The disease occurred in late autumn, affecting 6 to 11-year-old Aberdeen Angus and Hereford x Aberdeen Angus lactating multiparous cows in good body condition, grazing on natural grasslands that had been improved by fertilization and sowing of seeds of ryegrass and oat. Approximately 40 out of 225 cows were affected and 24 (10.7%) died. A presumptive diagnosis of hypomagnesemia was established based on sudden death, acute neuromuscular clinical signs, epidemiological data, and the response to Mg administration. The diagnosis was confirmed by detecting low Mg concentrations in serum (0.47-0.57mmol/L), vitreous humor (0.47-0.80mmol/L), aqueous humor (0.66mmol/L) and cerebrospinal fluid (0.59mmol/L). The largest component of the diet corresponding to fast-growing and exuberant forages of ryegrass and oat had high concentrations of K (3.48%), N (4.38%) and P (0.94%), suggesting secondary hypomagnesemia. In addition, the K/(Ca+Mg) ratio was 2.38 in forages of ryegrass and oat (reference value: 2.2), and 0.15 in the soil (reference value: 0.09), which represent risk factors for hypomagnesemia. In conclusion, hypomagnesemia is an important cause of mortality in beef cattle grazing improved natural grasslands in Uruguay and it can be easily prevented by correct seasonal Mg supplementation.

RESUMO: A hipomagnesemia é uma das principais causas de morte em vacas de corte em pastagem em países do Hemisfério Sul, como Argentina, Austrália e Nova Zelândia. Aqui, revisamos a literatura sobre hipomagnesemia em bovinos de corte e descrevemos um surto no Uruguai. A doença ocorreu no final do outono, afetando vacas Aberdeen Angus e Aberdeen Angus x Hereford de 6-11 anos de idade em boas condições corporais, lactantes, multíparas e pastando em campos naturais que foram melhorados com fertilização e plantio de azevém e aveia. Aproximadamente 40 de 225 vacas foram afetadas e 24 (10,7%) morreram. O diagnóstico presuntivo de hipomagnesemia foi estabelecido com base na morte súbita, sinais clínicos neuromusculares agudos, dados epidemiológicos e a resposta à administração de Mg. O diagnóstico foi confirmado pela detecção de baixos níveis de Mg no soro (0,47-0,57mmol/L), humor vítreo (0,47-0,80mmol/L), humor aquoso (0,66mmol/L) e líquido cefalorraquidiano (0,59mmol/L). O componente mais importante da dieta correspondia a pastagens de azevém e aveia de rápido crescimento, as quais apresentaram altas concentrações de K (3,48%), N (4,38%) e P (0,94%), que sugerem hipomagnesemia secundária. Além disso, a relação K/(Ca+Mg) foi de 2,38 em forragens de azevém e aveia (valor de referência: 2,2) e 0,15 no solo (valor de referência: 0,09), que representam fatores de risco para hipomagnesemia. Em conclusão, a hipomagnesemia é uma causa importante de mortalidade em gado de corte em pastagens naturais melhoradas no Uruguai e pode ser facilmente prevenida pela correta suplementação sazonal de Mg.

Clinical findings of equine leukoencephalomalacia / Achados clínicos de leucoencefalomalácia equina

Equine leukoencephalomalacia (LEM) is a disease caused by the ingestion of food, especially corn, contaminated by fumonisin, a Fusarium verticillioides (synonymous with F. moniliforme) metabolite. The clinical signs of brain injuries have an acute onset and rapid evolution. This study aimed to describe the clinical findings in 11 animals diagnosed with LEM, including cerebrospinal fluid (CSF) analysis. Of these animals, 91% (10/11) were horses, and only 9% (1/11) were asinine. The clinical localization of the lesions was 64% (7/10) cerebral, manifested mainly by altered mental state and behavioral disturbance, and 36% (4/11) were brainstem lesions, manifested by incoordination, head tilt, nystagmus, facial hypoalgesia, difficulty in apprehension, chewing, and swallowing food. Postmortem findings revealed that 82% (9/11) of the lesions were in the cerebrum and 18% (2/11) in the brainstem. CSF findings, such as xanthochromia (43%, 3/7), hyperproteinorrachia (50%, 3/6), and pleocytosis (43%, 3/7) were observed. The affected animals showed neurological signs that were compatible with cerebral and/or brainstem injuries. The CSF from animals with LEM may present with xanthochromia, hyperproteinorrachia, and pleocytosis, reinforcing the fact that this disease should be included in the differential diagnosis of encephalomyelopathies.(AU)

A leucoencefalomalácia (LEM) é uma enfermidade que acomete equídeos causada pela ingestão de milho e seus derivados e feno contaminados pela micotoxina fumonisina, um metabólito do fungo Fusarium verticillioides (sinônimo para F. moniliforme). Os sinais clínicos apresentam início agudo e evolução rápida e são decorrentes de lesões encefálicas. O objetivo deste estudo é descrever os achados clínicos de 11 equídeos diagnosticados com LEM, incluindo a análise do líquido cefalorraquidiano (LCR). 91% dos animais afetados eram equinos e somente 9% (1/11) era asinino. A localização clínica das lesões era 64% (7/10) cerebrais, manifestadas por alterações no estado mental e comportamento e 36% (4/10) no tronco encefálico, manifestadas por incoordenação, desvio lateral de cabeça, nistagmo, hipoalgesia da face e dificuldade de apreensão, mastigação e deglutição de alimentos. Comparativamente, os achados post mortem revelaram que 82% (9/11) das lesões eram no cérebro e 18% (2/11) no tronco encefálico. Alterações no LCR, tais como xantocromia (43%, 3/7), hiperproteinorraquia (50%, 3/6) e pleocitose (43%, 3/7), foram observadas. Os animais afetados apresentaram sinais clínicos compatíveis com lesões encefálicas e/ou de tronco cerebral. O LCR de animais com LEM pode apresentar xantocromia, hiperproteinorraquia, e pleocitose, reforçando que esta doença deve ser incluída como diagnóstico diferencial de encefalomielites.(AU)

Clinical findings of equine leukoencephalomalacia / Achados clínicos de leucoencefalomalácia equina

Equine leukoencephalomalacia (LEM) is a disease caused by the ingestion of food, especially corn, contaminated by fumonisin, a Fusarium verticillioides (synonymous with F. moniliforme) metabolite. The clinical signs of brain injuries have an acute onset and rapid evolution. This study aimed to describe the clinical findings in 11 animals diagnosed with LEM, including cerebrospinal fluid (CSF) analysis. Of these animals, 91% (10/11) were horses, and only 9% (1/11) were asinine. The clinical localization of the lesions was 64% (7/10) cerebral, manifested mainly by altered mental state and behavioral disturbance, and 36% (4/11) were brainstem lesions, manifested by incoordination, head tilt, nystagmus, facial hypoalgesia, difficulty in apprehension, chewing, and swallowing food. Postmortem findings revealed that 82% (9/11) of the lesions were in the cerebrum and 18% (2/11) in the brainstem. CSF findings, such as xanthochromia (43%, 3/7), hyperproteinorrachia (50%, 3/6), and pleocytosis (43%, 3/7) were observed. The affected animals showed neurological signs that were compatible with cerebral and/or brainstem injuries. The CSF from animals with LEM may present with xanthochromia, hyperproteinorrachia, and pleocytosis, reinforcing the fact that this disease should be included in the differential diagnosis of encephalomyelopathies.(AU)

A leucoencefalomalácia (LEM) é uma enfermidade que acomete equídeos causada pela ingestão de milho e seus derivados e feno contaminados pela micotoxina fumonisina, um metabólito do fungo Fusarium verticillioides (sinônimo para F. moniliforme). Os sinais clínicos apresentam início agudo e evolução rápida e são decorrentes de lesões encefálicas. O objetivo deste estudo é descrever os achados clínicos de 11 equídeos diagnosticados com LEM, incluindo a análise do líquido cefalorraquidiano (LCR). 91% dos animais afetados eram equinos e somente 9% (1/11) era asinino. A localização clínica das lesões era 64% (7/10) cerebrais, manifestadas por alterações no estado mental e comportamento e 36% (4/10) no tronco encefálico, manifestadas por incoordenação, desvio lateral de cabeça, nistagmo, hipoalgesia da face e dificuldade de apreensão, mastigação e deglutição de alimentos. Comparativamente, os achados post mortem revelaram que 82% (9/11) das lesões eram no cérebro e 18% (2/11) no tronco encefálico. Alterações no LCR, tais como xantocromia (43%, 3/7), hiperproteinorraquia (50%, 3/6) e pleocitose (43%, 3/7), foram observadas. Os animais afetados apresentaram sinais clínicos compatíveis com lesões encefálicas e/ou de tronco cerebral. O LCR de animais com LEM pode apresentar xantocromia, hiperproteinorraquia, e pleocitose, reforçando que esta doença deve ser incluída como diagnóstico diferencial de encefalomielites.(AU)

Central nervous system infiltration in acute lymphoblastic leukemia in a dog

Background: Acute lymphoblastic leukemia (ALL) is a malignant neoplasia in which there is proliferation of lymphoid progenitor cells in the bone marrow, blood, and extramedullary sites. This disorder has a fast and progressive development; in dogs, cases of infiltration of ALL cells in the central nervous system (CNS) are uncommon and rare. Diagnosis can be achieved with the help of the clinical history and physical, radiographic, hematological, myelographic, and cerebrospinal fluid (CSF) tests in patients with or without neurological clinical signs. The present report aims to describe a case of ALL and the presence of lymphoblasts in the CSF of a dog with neurological clinical signs. Case: An 8-year-old Lhasa Apso dog was examined at the Veterinary Hospital of Universidade Federal do Paraná, Curitiba campus. At the physical examination, the animal exhibited apathy and paralysis of pelvic limbs, which progressed to tetraplegia. Abdominal palpation revealed presence of hepatosplenomegaly and absence of lymphadenomegaly. No alterations were observed in radiographs of the cervical, thoracic or lumbar spine. A complete blood count revealed presence of non-regenerative anemia (hematocrit = 22%), extreme lymphocytosis (185,229 cells/µL), lymphoblasts at a level of 72% (133,364 cells/µL), and thrombocytopenia (66,000 platelets/µL). The biochemical tests revealed increased alkaline phosphatase (859 IU/L). The levels of alanine aminotransferase, creatinine, urea, total protein, albumin, and globulin were normal. The diagnosis of ALL was achieved with the help of a myelogram. The myelogram findings included 39% of mature lymphocytes and 59% of lymphoblasts exhibiting large size, spherical shape, poorly delimited borders, with a high nucleus/cytoplasm ratio, marked cytoplasmic basophilia, and 2 to 3 evident nucleoli; metarubricytes (1%) and promyelocytes (0.6%) were also observed. The CSF contained an increased number of nucleated cells (27 cells/µL) comprising lymphocytes (43%), macrophages (33%), and segmented neutrophils (24%). Of the 11.6 lymphocytes per µL of CSF, 8.1 were lymphoblasts, which indicates infiltration of ALL cells in the CNS. The animal died one day after collection of bone barrow and CSF. Discussion: Relevant alterations observed in this case included the neurological signs caused by the infiltration of neoplastic cells in the CNS, severe leukocytosis and lymphocytosis, with large amounts of lymphoblasts in the blood and predominance of lymphoblasts in the bone marrow, which are alterations typically found in ALL. The animal also exhibited non-regenerative anemia and thrombocytopenia, which were secondary to infiltration of leukemic cells in the bone marrow. The CSF exhibited pleocytosis (27 cells/ µL), and 30% of the cells observed were lymphoblasts. Lymphoblast infiltration in the CNS of leukemic dogs is rare, and other studies have reported absence of neurological signs or neurological signs different from those observed in the present study. CSF analysis in indicated in cases of leukemia to assess leukemic cell infiltration in the CNS. In the case reported here, the plasma level of alkaline phosphatase was increased (859 IU/L) as a consequence of hepatomegaly and hepatic cholestasis. ALL is a very aggressive, proliferative neoplasia, and the resulting lymphoblasts infiltrated the CNS of the animal. In cases of ALL, performing complete blood count, myelogram, and CSF analysis is indicated whether the patients exhibit neurological signs or not.(AU)

Meningomielite eosinofílica provavelmente associada à toxoplasmose em um gato / Eosinophilic meningomyelitis probably associated with toxoplasmosis in a cat

Background: The cerebrospinal fluid (CSF) of healthy cats presents up to 5 cells/µL, with predominance of mononuclear cells and the presence of more than 1% eosinophils is rare and should always be considered an abnormal finding. There is no consensus on the term eosinophilic pleocytosis, as it is used to indicate the presence of more than 10 eosinophils/µL or more than 10% of the total leukocytes. The increase in eosinophils in the CSF may result from infectious, inflammatory, neoplastic and idiopathic diseases. The objective of this paper is to report a case of marked pleocytosis in CSF, with 84% eosinophils, probably due to toxoplasmosis, in a cat with paraparesis and diffuse spinal pain. Case: A mixed breed female cat, neutered, adult and domiciled in a rural area was presented due to gait abnormalities in the pelvic limbs that started one day before presentation. The general physical examination was unremarkable. On neurological examination it was observed asymmetric deficit of postural reactions in pelvic limbs, patellar reflex normal to increased and pain elicited on palpation of the thoracic and lumbar spine. Based on these findings, the neurological syndrome was classified as thoracolumbar, but with diffuse pain, and the main differential diagnoses were inflammatory/ infectious and neoplastic diseases. The leukogram showed eosinophilia and the serum biochemistry showed no significant changes. Serological assays for feline immunodeficiency virus and feline leukemia virus were negative. Analysis of cerebrospinal fluid (CSF) identified marked pleocytosis with 84% eosinophils and increase in protein concentration. Myelography showed no compressive or expansive changes. Fungal culture for CSF cryptococcosis was negative. Serum immunofluorescence antibody titer for Toxoplasma gondii (IgG) was 1:256. There was a marked improvement after treatment with sulfametoxazole/trimethoprim and pyrimethamine and after 3 weeks of treatment, there was almost complete recovery of neurological signs and after 9 months the cat was neurologically normal. Discussion: The most common causes of acute-onset thoracolumbar spinal cord syndrome in cats, with diffuse pain on spinal palpation, are meningomyelitis of inflammatory/infectious origin, such as feline infectious peritonitis (FIP) and neoplasms such as lymphoma. Other meningomyelitis of inflammatory origin, such as infectious and immune-mediated meningomyelitis of unknown origin are considered uncommon in cats. Although the clinical, systemic and neurological signs of FIP and toxoplasmosis may have similarities, in the present case FIP was not considered responsible for the observed signs, as the evolution of the case and the analysis of the CSF tend to be different. The peripheral eosinophilia, the cytological analysis of the CSF, characterized by marked eosinophilic pleocytosis, associated with a positive titer for toxoplasmosis, good response to treatment and improvement in the neurological condition, with survival for more than 9 months after treatment, rules out the possibility of FIP. Neurological signs observed in the absence of systemic signs are more common in cases of protozoan reactivation, which probably occurred in the present case. The possibility of toxoplasmosis in the patient in this report was reinforced by the fact that the animal came from a rural area. Eosinophilia of CSF is most commonly associated with parasitic infections, although it can be caused by a variety of infectious agents, but in the cat of the present report, the marked eosinophilic pleocytosis was likely due to toxoplasmosis, which is a rare occurrence in this specie. In conclusion, toxoplasmosis should be considered in the differential diagnosis of focal spinal cord lesions in cats. The identification of laboratory findings as well as the appropriate therapy favored the good evolution of the condition.

Antibioticoterapia no tratamento de infecções bacterianas do sistema nervoso central de pequenos animais / Antibiotic therapy in the treatment of bacterial infectionsof the small animal central nervous system

Infecções no sistema nervoso central (SNC) são menos prevalentes do que em outros órgãos e o tratamento é desafiador. Entre os fatores que tornam o tratamento de infecções bacterianas complicado nesse tecido, destacam se o fato do mesmo ser envolto pela barreira hematoencefálica, além da dificuldade de obter resultados positivos ao tentar isolar o agente causador por meio de punção de líquido cefalorraquidiano (LCR). Objetiva-se, nesse trabalho, documentar documentar os principais antibióticos utilizados para tratar infecções bacterianas no sistema nervoso central e a interação com a barreira hematoencefálica (BHE). Os antibióticos com ótima penetração na BHE são: trimetoprim, sulfonamidas, metronidazol e cloranfenicol com penetração penetração intermediária são: oxacilinas, penicilinas, ceftriaxone, moxalactam, tetraciclinas e carbenicilina; e com pequena penetração são: aminoglicosídeos, cefalosporinas de primeira geração e clindamicina. É fundamental para a escolha do antibiótico mais adequado para cada caso conhecer características da barreira hematoencefálica, além de determinar a farmacocinética e farmacodinâmica dos antibióticos e seus principais agentes etiológicos. Percebe-se que na literatura veterinária há escassos relatos descrevendo aspectos de farmacocinética e farmacodinâmica nas espécies felina e canina, sendo necessária maior maior quantidade de estudos nesta área.

Although infections in the central nervous system are less common than infections in other organics systems, they can cause life-threatening consequences and are a challenge for small animal practitioners. Among the factors that make these infections difficult to treat are the fact that it is surrounded by the blood-brain barrier, that hinders penetration of many substances, and the difficulty of obtaining positive results when trying to isolate the causative agent through spinal tap. This article aims to describe the blood-brain barrier, the most common antimicrobials used to treat bacterial infections in the central nervous system and their main applications in small animal practice. In the veterinary literature, trimethoprim, sulfonamides, chloramphenicol, and metronidazole are cited as antimicrobials with excellent penetration on the blood-brain barrier; oxacillin, penicillin's, ceftriaxone, moxalactam, tetracyclines and carbenicillin with intermediate penetration; and aminoglycosides, first-generation cephalosporins, and clindamycin with little penetration. It was concluded that knowing the blood-brain barrier characteristics, pharmacokinetics and pharmacodynamics of antimicrobial agents, along with the main etiological agents, are the key to choose the most appropriate antibiotic to be applied in each individual case. It is noticed that in the veterinary literature there are few reports describing aspects of pharmacokinetics and pharmacodynamics in feline and canine species, requiring more studies in this area.

Hypomagnesemia in beef cattle / Hipomagnesemia em bovinos de corte

Hypomagnesemia is a major cause of death in grazing beef cows in countries of the Southern Hemisphere such as Argentina, Australia and New Zealand. Here we review the literature on hypomagnesemia in beef cattle and describe an outbreak in Uruguay. The disease occurred in late autumn, affecting 6 to 11-year-old Aberdeen Angus and Hereford x Aberdeen Angus lactating multiparous cows in good body condition, grazing on natural grasslands that had been improved by fertilization and sowing of seeds of ryegrass and oat. Approximately 40 out of 225 cows were affected and 24 (10.7%) died. A presumptive diagnosis of hypomagnesemia was established based on sudden death, acute neuromuscular clinical signs, epidemiological data, and the response to Mg administration. The diagnosis was confirmed by detecting low Mg concentrations in serum (0.47-0.57mmol/L), vitreous humor (0.47-0.80mmol/L), aqueous humor (0.66mmol/L) and cerebrospinal fluid (0.59mmol/L). The largest component of the diet corresponding to fast-growing and exuberant forages of ryegrass and oat had high concentrations of K (3.48%), N (4.38%) and P (0.94%), suggesting secondary hypomagnesemia. In addition, the K/(Ca+Mg) ratio was 2.38 in forages of ryegrass and oat (reference value: 2.2), and 0.15 in the soil (reference value: 0.09), which represent risk factors for hypomagnesemia. In conclusion, hypomagnesemia is an important cause of mortality in beef cattle grazing improved natural grasslands in Uruguay and it can be easily prevented by correct seasonal Mg supplementation.(AU)

A hipomagnesemia é uma das principais causas de morte em vacas de corte em pastagem em países do Hemisfério Sul, como Argentina, Austrália e Nova Zelândia. Aqui, revisamos a literatura sobre hipomagnesemia em bovinos de corte e descrevemos um surto no Uruguai. A doença ocorreu no final do outono, afetando vacas Aberdeen Angus e Aberdeen Angus x Hereford de 6-11 anos de idade em boas condições corporais, lactantes, multíparas e pastando em campos naturais que foram melhorados com fertilização e plantio de azevém e aveia. Aproximadamente 40 de 225 vacas foram afetadas e 24 (10,7%) morreram. O diagnóstico presuntivo de hipomagnesemia foi estabelecido com base na morte súbita, sinais clínicos neuromusculares agudos, dados epidemiológicos e a resposta à administração de Mg. O diagnóstico foi confirmado pela detecção de baixos níveis de Mg no soro (0,47-0,57mmol/L), humor vítreo (0,47-0,80mmol/L), humor aquoso (0,66mmol/L) e líquido cefalorraquidiano (0,59mmol/L). O componente mais importante da dieta correspondia a pastagens de azevém e aveia de rápido crescimento, as quais apresentaram altas concentrações de K (3,48%), N (4,38%) e P (0,94%), que sugerem hipomagnesemia secundária. Além disso, a relação K/(Ca+Mg) foi de 2,38 em forragens de azevém e aveia (valor de referência: 2,2) e 0,15 no solo (valor de referência: 0,09), que representam fatores de risco para hipomagnesemia. Em conclusão, a hipomagnesemia é uma causa importante de mortalidade em gado de corte em pastagens naturais melhoradas no Uruguai e pode ser facilmente prevenida pela correta suplementação sazonal de Mg.(AU)

Antibioticoterapia no tratamento de infecções bacterianas do sistema nervoso central de pequenos animais / Antibiotic therapy in the treatment of bacterial infectionsof the small animal central nervous system

Infecções no sistema nervoso central (SNC) são menos prevalentes do que em outros órgãos e o tratamento é desafiador. Entre os fatores que tornam o tratamento de infecções bacterianas complicado nesse tecido, destacam se o fato do mesmo ser envolto pela barreira hematoencefálica, além da dificuldade de obter resultados positivos ao tentar isolar o agente causador por meio de punção de líquido cefalorraquidiano (LCR). Objetiva-se, nesse trabalho, documentar documentar os principais antibióticos utilizados para tratar infecções bacterianas no sistema nervoso central e a interação com a barreira hematoencefálica (BHE). Os antibióticos com ótima penetração na BHE são: trimetoprim, sulfonamidas, metronidazol e cloranfenicol com penetração penetração intermediária são: oxacilinas, penicilinas, ceftriaxone, moxalactam, tetraciclinas e carbenicilina; e com pequena penetração são: aminoglicosídeos, cefalosporinas de primeira geração e clindamicina. É fundamental para a escolha do antibiótico mais adequado para cada caso conhecer características da barreira hematoencefálica, além de determinar a farmacocinética e farmacodinâmica dos antibióticos e seus principais agentes etiológicos. Percebe-se que na literatura veterinária há escassos relatos descrevendo aspectos de farmacocinética e farmacodinâmica nas espécies felina e canina, sendo necessária maior maior quantidade de estudos nesta área.(AU)

Although infections in the central nervous system are less common than infections in other organics systems, they can cause life-threatening consequences and are a challenge for small animal practitioners. Among the factors that make these infections difficult to treat are the fact that it is surrounded by the blood-brain barrier, that hinders penetration of many substances, and the difficulty of obtaining positive results when trying to isolate the causative agent through spinal tap. This article aims to describe the blood-brain barrier, the most common antimicrobials used to treat bacterial infections in the central nervous system and their main applications in small animal practice. In the veterinary literature, trimethoprim, sulfonamides, chloramphenicol, and metronidazole are cited as antimicrobials with excellent penetration on the blood-brain barrier; oxacillin, penicillin's, ceftriaxone, moxalactam, tetracyclines and carbenicillin with intermediate penetration; and aminoglycosides, first-generation cephalosporins, and clindamycin with little penetration. It was concluded that knowing the blood-brain barrier characteristics, pharmacokinetics and pharmacodynamics of antimicrobial agents, along with the main etiological agents, are the key to choose the most appropriate antibiotic to be applied in each individual case. It is noticed that in the veterinary literature there are few reports describing aspects of pharmacokinetics and pharmacodynamics in feline and canine species, requiring more studies in this area.(AU)

Hypomagnesemia in beef cattle / Hipomagnesemia em bovinos de corte

Hypomagnesemia is a major cause of death in grazing beef cows in countries of the Southern Hemisphere such as Argentina, Australia and New Zealand. Here we review the literature on hypomagnesemia in beef cattle and describe an outbreak in Uruguay. The disease occurred in late autumn, affecting 6 to 11-year-old Aberdeen Angus and Hereford x Aberdeen Angus lactating multiparous cows in good body condition, grazing on natural grasslands that had been improved by fertilization and sowing of seeds of ryegrass and oat. Approximately 40 out of 225 cows were affected and 24 (10.7%) died. A presumptive diagnosis of hypomagnesemia was established based on sudden death, acute neuromuscular clinical signs, epidemiological data, and the response to Mg administration. The diagnosis was confirmed by detecting low Mg concentrations in serum (0.47-0.57mmol/L), vitreous humor (0.47-0.80mmol/L), aqueous humor (0.66mmol/L) and cerebrospinal fluid (0.59mmol/L). The largest component of the diet corresponding to fast-growing and exuberant forages of ryegrass and oat had high concentrations of K (3.48%), N (4.38%) and P (0.94%), suggesting secondary hypomagnesemia. In addition, the K/(Ca+Mg) ratio was 2.38 in forages of ryegrass and oat (reference value: 2.2), and 0.15 in the soil (reference value: 0.09), which represent risk factors for hypomagnesemia. In conclusion, hypomagnesemia is an important cause of mortality in beef cattle grazing improved natural grasslands in Uruguay and it can be easily prevented by correct seasonal Mg supplementation.(AU)

A hipomagnesemia é uma das principais causas de morte em vacas de corte em pastagem em países do Hemisfério Sul, como Argentina, Austrália e Nova Zelândia. Aqui, revisamos a literatura sobre hipomagnesemia em bovinos de corte e descrevemos um surto no Uruguai. A doença ocorreu no final do outono, afetando vacas Aberdeen Angus e Aberdeen Angus x Hereford de 6-11 anos de idade em boas condições corporais, lactantes, multíparas e pastando em campos naturais que foram melhorados com fertilização e plantio de azevém e aveia. Aproximadamente 40 de 225 vacas foram afetadas e 24 (10,7%) morreram. O diagnóstico presuntivo de hipomagnesemia foi estabelecido com base na morte súbita, sinais clínicos neuromusculares agudos, dados epidemiológicos e a resposta à administração de Mg. O diagnóstico foi confirmado pela detecção de baixos níveis de Mg no soro (0,47-0,57mmol/L), humor vítreo (0,47-0,80mmol/L), humor aquoso (0,66mmol/L) e líquido cefalorraquidiano (0,59mmol/L). O componente mais importante da dieta correspondia a pastagens de azevém e aveia de rápido crescimento, as quais apresentaram altas concentrações de K (3,48%), N (4,38%) e P (0,94%), que sugerem hipomagnesemia secundária. Além disso, a relação K/(Ca+Mg) foi de 2,38 em forragens de azevém e aveia (valor de referência: 2,2) e 0,15 no solo (valor de referência: 0,09), que representam fatores de risco para hipomagnesemia. Em conclusão, a hipomagnesemia é uma causa importante de mortalidade em gado de corte em pastagens naturais melhoradas no Uruguai e pode ser facilmente prevenida pela correta suplementação sazonal de Mg.(AU)

Cerebrospinal fluid analysis in 58 ruminants showing neurological disorders / Análise do líquido cefalorraquidiano em 58 ruminantes com distúrbios neurológicos

Ruminants may be affected by a wide variety of central nervous system (CNS) diseases. Cerebrospinal fluid (CSF) analysis forms the basis for ante mortem diagnostic evaluation of ruminants with clinical signs involving the CNS. Despite its importance as a tool to aid diagnosis, data regarding CSF examinations in spontaneous cases of CNS diseases in ruminants from Brazil are limited, and most reports involve experimental studies. Therefore, this study aimed to report the results of CSF analysis in 58 ruminants showing signs of neurological disorders. CSF samples for analysis were obtained from 32 cattle, 20 sheep, and 6 goats by cerebello-medullary cistern (n=54) or lumbosacral space (n=4) puncture. These ruminants showed neurological signs related to viral (n=13), mycotic (n=3), or bacterial (n=15) infections, and toxic (n=21), traumatic (n=4), or congenital disorders (n=2). CSF analysis from ruminants with viral infections presented lymphocytic pleocytosis, even though CSF showed no changes in several cases of rabies. Neutrophilic pleocytosis, cloudiness, presence of fibrin clots, and abnormal coloration were evident in the CSF of most cases of CNS bacterial infection, such as meningoencephalitis, meningitis, abscesses, myelitis, and a case of conidiobolomycosis. On the other hand, CSF was unchanged in most cases of toxic disorders, as botulism and hepatic encephalopathy. Elevated CSF density was observed in 60% of ruminants diagnosed with polioencephalomalacia. Our findings show that evaluation of CSF is a valuable diagnostic tool when used in association with epidemiological, clinical and pathological findings for diagnosis of CNS diseases in ruminants.(AU)

Os ruminantes podem ser afetados por uma grande variedade de doenças do sistema nervoso central (SNC). A análise do líquido cefalorraquidiano (LCR) constitui a base da avaliação diagnóstica ante mortem de ruminantes com sinais clínicos envolvendo o SNC. Apesar de sua importância como ferramenta para auxiliar no diagnóstico, os dados referentes aos exames do LCR em casos espontâneos de doenças do SNC em ruminantes no Brasil são limitados, e, a maioria dos relatos envolve estudos experimentais. Portanto, este trabalho teve como objetivo relatar os resultados da análise do LCR em 58 ruminantes com distúrbios neurológicos. Amostras do LCR foram obtidas de 32 bovinos, 20 ovinos e 6 caprinos por punção da cisterna cerebelo-medular (n=54) ou espaço lombossacro (n=4) para posterior análise. Esses ruminantes apresentaram sinais neurológicos relacionados a infecções virais (n=13), micóticas (n=3) ou bacterianas (n=15), e desordens tóxicas (n=21), traumáticas (n=4) ou congênitas (n=2) A análise do LCR de ruminantes com infecções virais apresentou pleocitose linfocítica, embora, em vários casos de raiva, o LCR não tenha apresentado alterações. Pleocitose neutrofílica, turbidez, presença de coágulos de fibrina e coloração anormal foram evidentes no LCR da maioria dos casos de infecções bacterianas do SNC, como meningoencefalites, meningites, abscessos, mielite e um caso de conidiobolomicose. Por outro lado, o LCR não foi alterado na maioria dos casos dos distúrbios tóxicos, como botulismo e encefalopatia hepática. A densidade elevada no LCR foi observada em 60% dos ruminantes diagnosticados com polioencefalomalácia. Nossos resultados mostram que a avaliação do LCR é uma valiosa ferramenta de diagnóstico, quando usada em associação com os achados epidemiológicos, clínicos e patológicos para o diagnóstico de doenças do SNC em ruminantes.(AU)

Cerebrospinal fluid analysis in 58 ruminants showing neurological disorders / Análise do líquido cefalorraquidiano em 58 ruminantes com distúrbios neurológicos

Ruminants may be affected by a wide variety of central nervous system (CNS) diseases. Cerebrospinal fluid (CSF) analysis forms the basis for ante mortem diagnostic evaluation of ruminants with clinical signs involving the CNS. Despite its importance as a tool to aid diagnosis, data regarding CSF examinations in spontaneous cases of CNS diseases in ruminants from Brazil are limited, and most reports involve experimental studies. Therefore, this study aimed to report the results of CSF analysis in 58 ruminants showing signs of neurological disorders. CSF samples for analysis were obtained from 32 cattle, 20 sheep, and 6 goats by cerebello-medullary cistern (n=54) or lumbosacral space (n=4) puncture. These ruminants showed neurological signs related to viral (n=13), mycotic (n=3), or bacterial (n=15) infections, and toxic (n=21), traumatic (n=4), or congenital disorders (n=2). CSF analysis from ruminants with viral infections presented lymphocytic pleocytosis, even though CSF showed no changes in several cases of rabies. Neutrophilic pleocytosis, cloudiness, presence of fibrin clots, and abnormal coloration were evident in the CSF of most cases of CNS bacterial infection, such as meningoencephalitis, meningitis, abscesses, myelitis, and a case of conidiobolomycosis. On the other hand, CSF was unchanged in most cases of toxic disorders, as botulism and hepatic encephalopathy. Elevated CSF density was observed in 60% of ruminants diagnosed with polioencephalomalacia. Our findings show that evaluation of CSF is a valuable diagnostic tool when used in association with epidemiological, clinical and pathological findings for diagnosis of CNS diseases in ruminants.(AU)

Os ruminantes podem ser afetados por uma grande variedade de doenças do sistema nervoso central (SNC). A análise do líquido cefalorraquidiano (LCR) constitui a base da avaliação diagnóstica ante mortem de ruminantes com sinais clínicos envolvendo o SNC. Apesar de sua importância como ferramenta para auxiliar no diagnóstico, os dados referentes aos exames do LCR em casos espontâneos de doenças do SNC em ruminantes no Brasil são limitados, e, a maioria dos relatos envolve estudos experimentais. Portanto, este trabalho teve como objetivo relatar os resultados da análise do LCR em 58 ruminantes com distúrbios neurológicos. Amostras do LCR foram obtidas de 32 bovinos, 20 ovinos e 6 caprinos por punção da cisterna cerebelo-medular (n=54) ou espaço lombossacro (n=4) para posterior análise. Esses ruminantes apresentaram sinais neurológicos relacionados a infecções virais (n=13), micóticas (n=3) ou bacterianas (n=15), e desordens tóxicas (n=21), traumáticas (n=4) ou congênitas (n=2) A análise do LCR de ruminantes com infecções virais apresentou pleocitose linfocítica, embora, em vários casos de raiva, o LCR não tenha apresentado alterações. Pleocitose neutrofílica, turbidez, presença de coágulos de fibrina e coloração anormal foram evidentes no LCR da maioria dos casos de infecções bacterianas do SNC, como meningoencefalites, meningites, abscessos, mielite e um caso de conidiobolomicose. Por outro lado, o LCR não foi alterado na maioria dos casos dos distúrbios tóxicos, como botulismo e encefalopatia hepática. A densidade elevada no LCR foi observada em 60% dos ruminantes diagnosticados com polioencefalomalácia. Nossos resultados mostram que a avaliação do LCR é uma valiosa ferramenta de diagnóstico, quando usada em associação com os achados epidemiológicos, clínicos e patológicos para o diagnóstico de doenças do SNC em ruminantes.(AU)