Giselle de Lima Bernardes

Resumo O objetivo deste estudo foi monitorar a morfologia das ondas da pressão intracraniana de forma não invasiva (Ni-ICP) e avaliar a razão P2/P1 em cães saudáveis sob anestesia geral com propofol em diferentes ângulos de elevação da cabeceira do leito (HOB). 23 animais foram incluídos. Dados de sete animais foram excluídos pois o excesso de artefatos na forma de onda inviabilizou a análise confiável da Ni-ICP, resultando em uma amostra final de 16 animais. Após indução e manutenção anestésica com infusão contínua de propofol, os animais foram posicionados em decúbito lateral sobre uma prancha reclinável. A morfologia das ondas da Ni-ICP foi registrada utilizando um sensor do tipo extensômetro colocado sobre a pele da região parietal do crânio. O monitoramento foi realizado com a HOB em 0°, 15° e 30°, e novamente a 0°. Os dados foram apresentados como média ± desvio-padrão. A ANOVA de medidas repetidas foi utilizada para comparar a razão P2/P1 entre as diferentes posições de elevação da cabeceira, enquanto a correlação de Pearson, com correção para múltiplas comparações pelo método de Benjamini–Hochberg (False Discovery Rate – FDR), foi empregada para avaliar a associação entre a razão P2/P1 e as variáveis fisiológicas. O nível de significância adotado foi de p < 0,05. A idade média dos cães foi de 1,7 anos e o peso corporal médio foi de 4,4 kg. A razão P2/P1 média foi de 0,91 ± 0,17 em 0°, 1,00 ± 0,22 em 15°, 0,93 ± 0,26 em 30°, e 0,91 ± 0,23 após o retorno a 0°. Não foram encontradas diferenças significativas na razão P2/P1 média entre os diferentes ângulos de HOB. Esses achados fornecem valores de referência preliminares para as ondas da PIC-Ni e para a razão P2/P1 em cães saudáveis sob condições experimentais. Além disso, estabelecem um referencial metodológico para futuros estudos que avaliem o posicionamento da cabeça em cães com suspeita de hipertensão intracraniana.

This study aimed to monitor non-invasive intracranial pressure (Ni-ICP) waveforms and evaluate P2/P1 ratios in healthy dogs under propofol general anesthesia at different head-of-bed (HOB) elevation angles. 23 animals were included. Data from seven animals were excluded because excessive waveform artifacts precluded reliable Ni-ICP analysis, resulting in a final sample of 16 animals. Following anesthetic induction and maintenance with continuous propofol infusion, animals were positioned in lateral recumbency on a reclining board. The Ni-ICP waveforms were recorded using a strain-gauge-type sensor placed on the skin over the skull. Monitoring was conducted at HOB of 0°, 15°, and 30° and again at 0°. Data are presented as mean ± standard deviation. Repeated-measures ANOVA was used to compare P2/P1 ratios among head-of-bed positions, and Pearson's correlation analysis with Benjamini–Hochberg false discovery rate correction was performed to assess associations between the P2/P1 ratio and physiological variables. Statistical significance was set at p < 0.05. The mean age of the dogs was 1.7 years, and the mean body weight was 4.4 kg. The average P2/P1 ratio was 0.91 ± 0.17 at 0° elevation, 1.00 ± 0.22 at 15°, 0.93 ± 0.26 at 30°, and 0.91 ± 0.23 after returning to 0°. No statistically significant differences were found in mean P2/P1 ratios across different elevation angles. These findings provide preliminary values for Ni-ICP waveforms and P2/P1 ratios in healthy dogs under experimental conditions. They establish a methodological framework for future studies evaluating HOB in dogs with suspected intracranial hypertension.

Contexto: Vários agentes infecciosos podem causar discospondilite, principalmente devido à disseminação hematogênica, sendo a infecção bacteriana a mais comum. A discopondilite fúngica é rara e pode resultar de infecção por vários agentes, incluindo Aspergillus spp. A aspergilose disseminada, que pode causar discospondilite, é mais prevalente em cães pastores alemães, possivelmente devido a defeitos genéticos nas respostas imunes celulares e humorais. Dada a raridade desta condição, o objetivo deste relato é descrever um caso de discopondilite fúngica causada por Aspergillus spp. em um cão pastor branco suíço jovem.Caso: Um cão pastor branco suíço de um ano e meio de idade foi atendido com histórico de paraparesia de início agudo que progrediu para paraplegia. O exame neurológico revelou síndrome toracolombar grau IV, caracterizada por paraplegia com perda de sensibilidade superficial nos membros pélvicos, ausência do reflexo do tronco cutâneo caudal à sexta vértebra torácica e dor à palpação manual da coluna em T4/T5/T6. Radiografias da coluna torácica foram realizadas, mas os resultados foram inconclusivos, levando ao encaminhamento para tomografia computadorizada (TC). A TC revelou áreas líticas nos corpos vertebrais T4-T5 e a presença de uma estrutura amorfa com densidade de tecido mole no espaço extradural em T4/T5, causando compressão da medula espinhal, consistente com o diagnóstico de discospondilite. Ultrassonografia abdominal e cultura de urina foram conduzidas para investigar a fonte primária de infecção, mas os resultados foram inconclusivos. A condição do paciente piorou apesar da terapia com antibióticos, levando à análise do líquido cefalorraquidiano e hemilaminectomia para descompressão da medula espinhal e coleta de material do disco entre T4/T5 para cultura fúngica e bacteriana. A cultura fúngica do granuloma e do material do disco foi positiva para Aspergillus spp. Consequentemente, a antibioticoterapia foi descontinuada e o tratamento com itraconazol foi iniciado. Dois meses após o início do tratamento antifúngico, não houve melhora do quadro neurológico e clínico, e o paciente foi eutanasiado.Discussão: A maioria dos relatos de aspergilose em cães no Brasil envolve o trato respiratório; portanto, o caso descrito neste estudo é provavelmente o primeiro relato de discoespondilite fúngica causada por Aspergillus spp. em um cão no país. Cães pastores alemães e suas variações, como o pastor branco suíço, podem ser mais suscetíveis à infecção fúngica por Aspergillus spp. devido a um defeito imunológico hereditário relacionado a níveis mais baixos de imunoglobulina A. A discoespondilite pode ser diagnosticada por exame radiográfico; no entanto, neste paciente, não foi observada lise da placa terminal ou proliferação óssea, o que pode ocorrer nos estágios iniciais da doença, pois as alterações radiográficas podem levar de duas a seis semanas para aparecer. Portanto, imagens avançadas, como tomografia computadorizada, foram necessárias. Dado que a discoespondilite bacteriana é muito mais comum do que a infecção fúngica, foi iniciada terapia com antibióticos, mas sem melhora da condição, levando à coleta de material de disco para análise microbiológica. Portanto, é importante incluir a discoespondilite fúngica e a aspergilose disseminada no diagnóstico diferencial para cães pastores alemães e suas variações com síndromes medulares de progressão rápida e que não respondem ao tratamento com antibióticos.

Monitorar a pressão intracraniana (PIC) permite otimizar o tratamento de pacientes com diversas afecções, já que a hipertensão intracraniana (HIC) pode causar isquemia. A aferição da PIC pode ser realizada de maneira invasiva, que é o método mais acurado, mas requer a introdução de um sensor no ventrículo ou parênquima, o que pode causar hemorragia e infecção. Existem ainda diversos métodos não invasivos, que aliados aos parâmetros clínicos, podem ser utilizados como alternativa para avaliar a PIC. O uso de cateter ventricular, epidural e microtransdutores são descritos na veterinária como métodos invasivos, porém, nenhum deles é considerado padrão ouro em pequenos animais, mas presume-se que o uso de microtransdutores intraparenquimatosos seja o mais preciso. Dentre os métodos não invasivos, a mensuração do diâmetro da bainha do nervo óptico (DBNO), ressonância magnética, ultrassonografia (US) com doppler transcraniano e elasticidade óssea intracraniana foram relatados. Em gatos, o DBNO foi mensurado por US transpalpebral em animais saudáveis e com HIC presumida e mostrou-se ser um método viável. A monitoração da PIC não é rotineiramente usada na medicina veterinária, mas poderia guiar e otimizar o tratamento em diversas afecções, portanto, objetivo desta revisão narrativa é descrever os métodos de monitoração da PIC em cães e gatos.

Background: Nonambulatory flaccid tetraparesis can be the result of diseases of the peripheral nervous system and it is characterized by generalized lower motor neuron (LMN) signs, as weakness, tetraparesis/tetraplegia, decreased muscle tone and reflexes. The term polyneuropathy is used for dysfunction of multiple peripheral nerves. In Brazil, there are several etiologies for polyneuropathy in dogs, such as acute idiopathic polyradiculoneuritis, botulism and myasthenia gravis. Toxoplasma gondii is an uncommon cause of LMN diseases in dogs. The aim of this report was to describe a case of flaccid tetraplegia probably caused by toxoplasmosis in an adult dog. Case: A 4-year-old, 19.6-kg, intact mongrel male dog, was presented with a 5-day history of weakness that progressed to tetraparesis. Physical examination revealed no significant changes other than the dull and unkempt coat. Neurologic examination revealed severe tetraparesis that was worse in the pelvic limbs, with decreased muscle tone in all four limbs. Postural reactions and the interdigital reflex were absent in all four limbs, as was the patellar reflex, but pain perception was present. There were no clinical signs of dysfunction on examination of the cranial nerves. Laboratory tests were performed, and creatine kinase was elevated (819 U/L). Blood was drawn to look for antibodies to Toxoplasma gondii and Neospora caninum class IgG using the indirect immunofluorescence technique. The antibody titer for Toxoplasma gondii (IgG) was 1:4096. A chest radiograph was performed to look for megaesophagus, and a pulmonary pattern suggestive of mild diffuse pneumonia was observed. Treatment was performed with sulfamethoxazole and trimethoprim, and the dog's condition improved slightly. Discussion: Based on lower motor neuron findings, the neurologic lesion was localized to nerve roots, peripheral nerves, neuromuscular junctions, and muscles. The most important diseases in the list of differential diagnoses were immune-mediated or infectious polyradiculoneuritis (toxoplasmosis, neosporosis), myasthenia gravis, toxic polyneuropathy (botulism, chronic organophosphate poisoning), and paraneoplastic polyneuropathy. Among these differential diagnoses, polyradiculoneuritis is one of the most common. It is an idiopathic inflammatory disease. Exposure to raccoon saliva (in the U.S.), vaccination, or infection have been proposed as precipitating causes, but the triggers of this disease remain unknown. Serology for neosporosis was negative, while IgG titers for toxoplasmosis were 1:4096. In a previous study, dogs with acute polyradiculoneuritis were more likely to have T. gondii IgG serum antibody titers than dogs without neurologic signs. Infection with the protozoa T. gondii and N. caninum can cause intense polyradiculoneuritis in dogs accompanied by myositis, especially in puppies. One treatment trial was based on the administration of sulfonamide-trimethoprim with pyrimethamine, whose efficacy in the treatment of toxoplasmosis in dogs has also been reported in the literature. Neurologic deficits improved slightly, and there is a possibility that certain signs may not disappear completely because of the permanent damage caused by inflammation of the nervous system, as observed in the present case. The case had the limitation that it was not possible to perform other laboratory tests to demonstrate histopathologically the presence of T. gondii organisms in muscles or nerves. Recovery of normal function is less likely in protozoan polyradiculoneuritis than in noninfectious polyradiculoneuritis. Thus, in the present case, the main suspicion was polyradiculoneuritis secondary to toxoplasmosis. Although it is a rare condition, it is important to consider toxoplasmosis in dogs with LMN-type tetraparesis or tetraplegia.

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 neutrophils. 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.Keywords: eosinophilic pleocytosis, feline, Toxoplasma gondii, cerebrospinal fluid.Descritores: pleocitose eosinofílica, felino, Toxoplasma gondii, líquido cerebroespinhal.