Listeriosis

The signs of bovine listeriosis include depression and variable cranial nerve deficits indicative of brain stem inflammation. Because a wide range of cranial nerve deficits exists in bovine listeriosis patients, a thorough neurologic examination and cerebrospinal fluid analysis are essential to accurate diagnosis. Treatment should consist of intensive antibiotic therapy owing to the intracellular location of the causative organisms and should also address metabolic acidosis in those patients with loss of buffer because of excessive salivation. The public health implications of bovine listeriosis require the veterinarian to protect all persons attending the bovine patient affected with listeriosis.     

Neurologic evaluation of the ear.

Diseases of the ear often cause signs of neurologic dysfunction because of damage of peripheral nervous system structures associated with the middle and inner ear. Vestibular dysfunction, facial paralysis, Horner's syndrome, and hearing deficits are the most common neurologic deficits that accompany middle and inner ear disease. Differentiating these signs from disease of the central nervous system is crucial for an accurate diagnosis and prognosis but can be difficult. Understanding the normal anatomy of the ear and its association with the brain is crucial to interpretation of the neurologic examination. This article reviews neurologic dysfunction commonly associated with diseases of the ear and differentiating these signs from central disease.     

The neurologic examination of the horse for purchase.

The veterinarian needs to be able to incorporate an accurate neurologic examination as a portion of the pre-purchase evaluation. Subtle neurologic deficits may be hidden by musculoskeletal disease or missed as a result of lack of knowledge or understanding of these disorders. It is important to known which musculoskeletal disorders are commonly associated with neurologic disease to better assist the buyer with the decision about whether to purchase the animal.     

Approach to the patient with spinal disease.

The approach to the patient suspected of having spinal disease should be methodical to assure an accurate diagnosis that is cost-effective with minimal risk to the patient. Using a problem-oriented approach will facilitate attaining this goal. A neurologic examination should enable the veterinarian to localize to one of four spinal cord segments or the cauda equina.     

Assessment of the nervous system.

This article describes the examination of the neurologic and ophthalmic systems in ruminants. Neuroanatomy with respect to lesion localization is reviewed. Pertinent age and species differences are addressed. The practical aspects of assessing the neurologic system are stressed, and the reader is directed to other sources of information for assistance in determining the differential diagnosis and therapy of neurologic disease.     

Hypovolemic hyponatremia and signs of neurologic disease associated with diarrhea in a foal.

Hypovolemic hyponatremia attributable to severe fluid and electrolyte alterations was diagnosed in a foal with diarrhea. Subsequent consumption of water resulted in rapid reduction of serum sodium concentration and serum osmolar depression. Clinical signs of neurologic disease developed including blindness, loss of menace response, and seizures. Treatment of this condition with IV administered fluids included hypertonic saline solution (7.2%; 2 ml/kg of body weight), and frequent monitoring of serum electrolyte concentrations and osmolality resulted in gradual correction of the fluid and electrolyte imbalance and resolution of the neurologic signs. Hyponatremia has been recognized in foals with renal failure, ruptured urinary bladder, and iatrogenic water overload. The key to diagnosis and management of profound hyponatremia is accurate diagnosis of the status of plasma volume and association of the electrolyte imbalance with clinical signs of neurologic disease. This report describes an unusual complication of a commonly encountered problem in equine practice and documents that the severe metabolic and electrolyte abnormalities associated with diarrhea can result in clinical neurologic disease. The differential diagnosis also should include bacterial sepsis, parasitism, thoracic mass, acute renal failure, congenital neurologic deficit, or seizure syndrome. Serum electrolyte disorders should be considered as a potential cause of signs of neurologic disease in foals with diarrhea.     

Viral diseases of the ruminant nervous system.

This article presents the etiology, epidemiology, clinical features,and diagnosis of the primary viral neurologic diseases observed in ruminants. In general, these viral neurologic diseases are uncommon but often fatal. Rabies virus is perhaps the most important cause of encephalitis in cattle because of the public health implications. Other viral encephalitis diseases in ruminants include bovine herpesvirus encephalomyelitis, pseudorabies, malignant catarrhal fever, ovine and caprine lentiviral encephalitis, West Nile virus encephalitis, Borna disease, paramyxoviral sporadic bovine encephalomyelitis,and ovine encephalomyelitis (louping-ill).     

牛传染性鼻气管炎诊断方法研究进展

牛传染性鼻气管炎(IBR)是由牛传染性鼻气管炎病毒(IBRV),即牛疱疹病毒1型(BoHV-1)所引起的以上呼吸道炎症为主的一种牛的急性、热性、接触性传染病,呈世界性流行。IBR的早期准确诊断,对该病的防控具有不可忽视的作用。目前,IBR的诊断方法主要包括病原学诊断和血清学诊断方法。病原学诊断具有特异和敏感及准确等特点,而血清学诊断具有敏感、快速、方便和价廉等特点。为了实施IBR的净化和根除计划,部分国家和地区已逐渐采用IBR基因缺失疫苗,配套使用鉴别诊断方法来鉴别IBR疫苗免疫和自然感染。论文就牛传染性鼻气管炎常用诊断方法的研究进展进行综述,以期为IBR的诊断和防控提供参考。     

Multisystem Neuronal Degeneration in Cocker Spaniels

Four young Cocker Spaniels had slowly progressive neurologic signs with ataxia and mental deterioration. Pathologically, the lesions consisted of diffuse nerve cell loss, gliosis, axonal degeneration, and some demyelination in several areas of the brain. Pedigree analysis strongly suggests a hereditary cause for this disease, which is classified as a multisystem neuronal degeneration. This disorder has not been previously reported and has some resemblance to certain degenerative neurologic diseases found in humans. The clinical differential diagnosis includes cerebellar degeneration and lysosomal storage diseases. A definitive diagnosis requires postmortem examination.     

Cerebrospinal fluid cytology in canine neurologic disease

Samples of cerebrospinal fluid (CSF) of 93 dogs with neurologic diseases were examined by cytomorphologic technique, and the changes in the CSF were correlated with histopathologic examinations of the central nervous system (CNS). It was concluded that CSF examination is a significant aid in obtaining a neurologic diagnosis and that good correlation exists between the CSF changes and the pathologic changes in the CNS. The CSF examination allows making a diagnosis of encephalitis and differentiation between viral and other causes (although in mycotic infection the cell membrane preparation can be used to identify the cause directly), could allow making differentiation between congenital malformations and congenital degenerative disease, and helps in identifying physical spinal cord damage, differentiating it from muscular, neurogenic, or functional disorders clinically presented as spinal ataxia. The CSF cytologic examination can indicate the presence of hemorrhage in the CNS. There is not enough experience available in the diagnosis of brain tumors by means of CSF examination; however, in dogs with lymphosarcoma in the CNS, CSF cytologic changes can be diagnostic.     

Diagnostic Features of Clinical Neurologic Feline Infectious Peritonitis

Feline infectious peritonitis (FIP) is a fatal Arthus-type immune response of cats to infection with FIP virus, a mutant of the ubiquitous feline enteric coronavirus (FECV). The disease may occur systemically or in any single organ system, and primary neurologic disease is a common subset of such manifestations. We examined 16 domestic cats with clinical neurologic FIP and 8 control cats with nonneurologic FIP, with the intention of identifying the ante-and postmortem diagnostic tests that most contribute to accurate diagnosis. Of the 16 cats with neurologic FIP, 15 were less than 2 years of age and all 16 originated from large multiplecat households. The most useful antemortem indicators of disease were positive anti-coronavirus IgG titer in cerebrospinal fluid, high serum total protein concentration, and findings on magnetic resonance imaging suggesting periventricular contrast enhancement, ventricular dilatation, and hydrocephalus. Postmortem diagnosis was facilitated by FIP monoclonal antibody staining of affected tissue and coronavirus-specific polymerase chain reaction. Most cats with neurologic and ocular forms of FIP had patchy, focal lesions, suggesting that recently developed technologies described in this report may be useful for evaluation of cats with suspected FIP.     

Putative uremic encephalopathy in horses: five cases (1978-1998)

OBJECTIVE: To determine historical, physical examination, clinicopathologic, and postmortem findings in horses with putative uremic encephalopathy. Design-Retrospective study. Animals-5 horses with renal failure and neurologic disease not attributable to abnormalities in any other organ system. PROCEDURE: Medical records from 1978 to 1998 were examined for horses with renal disease and neurologic signs not attributable to primary neurologic, hepatic, or other diseases. Signalment, history, physical examination findings, clinicopathologic data, renal ultrasonographic findings, and postmortem data were reviewed. RESULTS: Of 332 horses with renal disease, 5 met selection criteria. Historical findings, physical examination findings, clinicopathologic data, ultrasonographic data, and postmortem findings were consistent with chronic renal failure. Swollen astrocytes were detected in all 4 horses examined at necropsy. CONCLUSIONS AND CLINICAL RELEVANCE: A single criterion was not determined to be pathognomonic for uremic encephalopathy in horses. Uremic encephalopathy should be considered as a differential diagnosis in horses with evidence of chronic renal failure and encephalopathic neurologic sign not attributable to other causes. Astrocyte swelling, which was common to all 4 horses examined at necropsy, may serve as a microscopic indicator of uremic encephalopathy in horses.     

Medical management of spinal cord disease

In spinal cord disease of horses, a complete history, neurologic examination, and adjunctive diagnostic procedures are very helpful in establishing a tentative diagnosis; however, a definitive diagnosis may be difficult or impossible to establish antemortem. Medical management should be initiated with full consideration of possible etiologies and knowledge of the effects and consequences of medical therapies. This article discusses the drugs commonly used in the management of spinal cord disease and the rationale for their use.     

An atypical lymphoma of T-cell lineage in the thorax of an aged cow.

An aged beef cow was presented for signs of thoracic disease. A complete clinical and diagnostic workup suggested neoplasia. Postmortem examination revealed a lymphoma of T-cell lineage confined solely to the thoracic cavity, predominantly in lung tissue. The diagnosis was based on light and electron microscopy, immunohistochemistry, and negative bovine leukemia virus and bovine immunodeficiency virus results.     

Encephalitis in aborted bovine fetuses associated with Bovine herpesvirus 1 infection.

Brain tissue from 12 aborted bovine fetuses submitted to the Wisconsin Veterinary Diagnostic Laboratory revealed histologic lesions that consisted of glial nodules and variable degrees of mononuclear inflammation, microhemorrhage, neuronal necrosis, and cerebral cortical cavitation. A diagnosis of Bovine herpesvirus 1 (BHV-1) abortion had been made in all of these cases through multiple testing modalities. Brain tissue from 8 of the 12 fetuses was immunohistochemically stained with a monoclonal antibody specific to BHV-1, and, in 5 fetuses, there was positive intralesional staining of neurons, glial cells, and endothelial cells. This preliminary data suggested that herpesviral infection of brain tissue led to the described neurologic lesions. BHV-1 was then amplified from brain tissue in all 12 of the fetuses and was confirmed by partial sequencing of the thymidine kinase and glycoprotein C genes. To the authors' knowledge, neurologic lesions have not previously been described in BHV-1-infected fetuses, nor has BHV-1 previously been identified in bovine fetal brain tissue. The neurologic histopathology attributed to BHV-1 infection in these cases overlaps with the neurologic lesions produced by Neospora caninum, a common etiologic agent of bovine abortion. Therefore, when bovine fetal neurologic lesions are found, both etiologies should be considered and then distinguished by using additional diagnostic tools.     

Sodium distribution in the bovine brain

Fatal sodium intoxication can occur in many species, including cattle, and postmortem confirmation often includes brain sodium concentration determination. Published information regarding brain sodium distribution in cattle was not found in a literature review. Our study was designed to determine whether sodium is uniformly distributed throughout the bovine brain. Eight whole bovine brains were collected from adult cattle with no neurologic signs or history suggestive of sodium intoxication, and with a non-neurologic cause of death diagnosed on gross examination. Brains were divided mid-sagittally. One hemisphere of each brain was homogenized. Subsamples were obtained from the remaining hemisphere (rostral, caudal, and dorsal cerebral cortices; brainstem, thalamus, and cerebellum). Sodium concentrations of regions and homogenates were measured by inductively coupled plasma–mass spectrometry. Data were analyzed using repeated measures ANOVA with a pairwise post-test to compare mean sodium concentration of each region to mean homogenate sodium concentration. Brain sodium was not uniformly distributed; sodium concentrations in different regions of the same brain varied somewhat unpredictably. Homogenization of an entire brain hemisphere appears to be the ideal method of sample preparation to ensure accurate brain sodium concentration measurement in adult cattle.     

The control of bovine leukosis in denmark, Epidemiologic and diagnostic aspects.

The Danish programme to control bovine enzootic leukosis was initiated in 1959 and intensified in 1969. The programme has resulted in a sharp decline in total and relative numbers of leukotic tumor cases in adult animals. However, total eradication of bovine leukosis has not yet been achieved, and the statistics from recent years seem to indicate that the present programme based on haematological and histological examinations will control but not eradicate the disease. An immunodiffusion test based on an internal protein (p 24) antigen has been used experimentally. This test is a valuable tool in herd diagnosis, but it is not sensitive enough for accurate single animal diagnosis.     

Pediatric neurology of the dog and cat.

The neurologic examination in the puppy or kitten can be a challenging experience. Understanding the development of behavior reflexes and movement in puppies and kittens enables us to overcome some of these challenges and to recognize the neurologically abnormal patient. Subsequently,we can identify the neuroanatomic localization and generate a differential diagnosis list. This article first reviews the pediatric neurologic examination and then discusses diseases unique to these individuals.