Tumors affecting the spinal cord of cats: 85 cases (1980-2005)

OBJECTIVE: To determine the prevalence of lymphosarcoma and other tumors affecting the spinal cord of cats and to relate specific types of tumors with signalment, history, and clinical findings. DESIGN: Retrospective case series. ANIMALS: 85 cats with tumors affecting the spinal cord. PROCEDURES: Medical records of cats with histologically confirmed primary or metastatic tumors of the spinal cord or tumors causing spinal cord disease by local extension from adjacent tissues examined between 1980 and 2005 were reviewed. Data on signalment; clinical history; results of neurologic examination, diagnostic imaging, and clinical pathologic evaluation; and location of tumor within the spinal cord were obtained from medical records and analyzed by use of logistic regression models. RESULTS: Lymphosarcoma was the most common tumor and affected the spinal cord in 33 (38.8%) cats, followed by osteosarcoma in 14 (16.5%) cats. Cats with lymphosarcoma were typically younger at initial examination, had a shorter duration of clinical signs, and had lesions in more regions of the CNS than did cats with other types of tumors. In 22 of 26 (84.6%) cats with lymphosarcoma, the tumor was also found in extraneural sites. CONCLUSIONS AND CLINICAL RELEVANCE: Data for spinal cord tumors in this population of cats were analyzed by logistic regression analysis, which effectively distinguished cats with lymphosarcoma from cats with other types of tumors. Additional clinical information reported here will help to increase the index of suspicion or definitive antemortem diagnosis of spinal cord tumors of cats.     

Survival rates and outcomes in cats with thoracic and lumbar spinal cord injuries due to external trauma

Survival rates and outcome were retrospectively examined in 30 cats with traumatic spinal cord lesions to the thoracic and lumbar spine. Treatment included both surgical and non-surgical management. In cats with loss of deep pain sensation, a high incidence of myelomalacia was found during surgery or postmortem examination. The outcome in cats with grade II and III neurological dysfunction (11/18) was poor in two cases, functional in one and complete in eight. Recovery in cats with grade IV neurological dysfunctions (7/18) was poor in one case, functional in two and complete in four. The other 12 of the original 30 cats were euthanased within four days of presentation. The results of this study are compared with those reported in cats with spinal injuries due to spontaneous disc herniations and to those that have been achieved in cats with experimental transections of the spinal cord.     

Lameness of the hindlimbs of the cat

About six to seven per cent of cats presented at the clinic show neurological signs. The largest group consists of traumatized cats. A complete neurological examination is essential for localizing the lesion and establishing a prognosis. Differential diagnosis for paraparesis/paraplegia of pelvic limbs in cats are discussed. Cats are demonstrated which had spinal cord trauma, disc protrusion, aortic thromboembolism and lumbosacral stenosis and the importance of the evaluation of x-rays, cerebrospinal fluid examination and myelography is stressed.     

Spontaneous lumbar intervertebral disc protrusion in cats: literature review and case presentations

Reports on intervertebral disc disease in cats are rare in the veterinary literature. It has been postulated that intervertebral disc protrusion is a frequent finding during necropsy in cats, without having any clinical relevance (King and Smith 1958, King & Smith 1960a, King & Smith 1960b). However, a total of six cases with disc protrusions and clinically significant neurological deficits have been reported over the past decade. (Heavner 1971, Seim & Nafe 1981, Gilmore 1983, Littlewood et al 1984, Sparkes & Skerry 1990, Bagley et al 1995). As in dogs, there are also two types of intervertebral disc disease in cats: Hansen's type I (extrusion), and type II (herniation). Cervical spinal cord involvement was more commonly recognised in cats than the lumbar or the thoraco lumbar area. Cats over 15 years were mainly affected (King & Smith 1958, King & Smith 1960a, King & Smith 1960b). We describe two cats with lumbar intervertebral disc protrusions. Emphasis is placed on differential diagnoses, treatment and follow-up.     

Polyneuropathies of cats

Polyneuropathies of cats have a variety of clinical presentations. Areflexic flaccid quadriparesis, or quadriplegia, progressing over a 24- to 48-hour period, may be associated with polyneuropathies, as can chronic insidiously progressive tremors and muscle weakness that wax and wane or progress slowly over weeks or months, and which can go undiagnosed for years. In addition, these neurological signs may be due to spinal cord, neuromuscular junction or muscle disorders, so the diagnosis of polyneuropathy can be a challenge even for the most astute of clinicians. Polyneuropathies may have congenital, inherited, inflammatory, metabolic and toxic causes. Sometimes the underlying aetiology is not found and a diagnosis of idiopathic polyneuropathy is made. Since the treatment and prognosis of polyneuropathies in cats vary, the purpose of this review is to assist the veterinary practitioner to recognise, appropriately manage and provide an accurate prognosis for these challenging cases.     

Characteristics of pain and response to analgesic treatment in dogs and cats examined at a veterinary teaching hospital emergency service

OBJECTIVE: To estimate the prevalence and characteristics of pain in dogs and cats examined by an emergency service at a veterinary teaching hospital and evaluate the response of dogs and cats with signs of pain to analgesic treatment. DESIGN: Cross-sectional study. ANIMALS: 317 dogs and 112 cats. PROCEDURE: A questionnaire was used to categorize the characteristics of pain. The location, cause, and signs of pain were determined by obtaining a thorough history and conducting a physical examination. Pain was categorized by type (superficial somatic, deep somatic, or visceral), mechanism (inflammatory, neuropathic, or both), severity (mild, moderate, or severe), and duration. Evidence for primary or secondary hypersensitivity and hyposensitivity to manipulation was determined. The response to single or multiple analgesic drug administration was assessed. RESULTS: 179 (56%) dogs and 60 (54%) cats had signs of pain. In most of these dogs and cats, pain was classified as acute (< 24 hours' duration) and of moderate severity and was associated with primary hypersensitivity. Most dogs had deep somatic pain; most cats had visceral pain. Inflammation was the most common mechanism. One hundred nineteen (66%) dogs and 41 (68%) cats were treated with analgesic drugs. Analgesic treatment was considered effective in 73 (61%) dogs and 31 (76%) cats. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that moderate to severe acute somatic pain caused by inflammation is common in dogs and cats examined by an emergency service and that a combination of multiple analgesic drugs is more effective than any single analgesic drug in the treatment of pain in these dogs and cats.     

Spinal dural ossification causing neurological signs in a cat

A six-year-old Ragdoll cat underwent examination due to a six-month history of slowly progressive gait abnormalities. The cat presented with an ambulatory tetraparesis with a neurological examination indicating a C1-T2 myelopathy. Radiographs of the spine showed a radiopaque irregular line ventrally in the vertebral canal dorsal to vertebral bodies C3-C5. In this area, magnetic resonance imaging revealed an intradural extramedullary/extradural lesion compressing the spinal cord. The spinal cord was surgically decompressed. The cause of the spinal cord compression was dural ossification, a diagnosis confirmed by histopathological examination of the surgically dissected sample of dura mater. The cat gradually improved after the procedure and was ambulating better than prior to the surgery. The cat’s locomotion later worsened again due to ossified plaques in the dura causing spinal cord compression on the same cervical area as before. Oral prednisolone treatment provided temporary remission. Ten months after surgery, the cat was euthanized due to severe worsening of gait abnormalities, non-ambulatory tetraparesis. Necropsy confirmed spinal cord compression and secondary degenerative changes in the spinal cord on cervical and lumbar areas caused by dural ossification. To our knowledge, this is the first report of spinal dural ossification in a cat. The reported cat showed neurological signs associated with these dural changes. Dural ossification should be considered in the differential diagnosis of compressive spinal cord disorders in cats.     

Prevalence of diseases of the spinal cord of cats

A retrospective review of records of 205 cats with histologically confirmed disease of the spinal cord was performed to identify the prevalence of disease in this nonrandomly selected population of cats. Clinical records were reviewed, and age, duration of neurologic illness, and clinical and histopathologic findings in cats with spinal cord disease were abstracted. Disease processes were classified into 7 categories and 23 groups. The most common diseases affecting the spinal cord of cats were feline infectious peritonitis (FIP), lymphosarcoma (LSA), and neoplasia of the vertebral column secondarily affecting the spinal cord. Information on age, onset and duration of clinical signs, and lesion localization at the postmortem examination in cats belonging to the 7 categories of disease were analyzed to create a practical list of differential diagnoses. Cats were also subcategorized into 3 groups based on their age at death. FIP was the most common disease of cats younger than 2 years of age. LSA and vertebral column neoplasia were the most common diseases affecting cats between 2 and 8 years of age. Vertebral column neoplasia was the most common disease affecting cats older than 8 years of age. Results of this histopathologic study showed that FIP and LSA were the most common disease processes affecting the spinal cord of cats. However, at least 21 other groups of diseases and their relative prevalence were identified.     

Neurological lameness in the cat: common causes and clinical approach

PRACTICAL RELEVANCE: Neurological causes of lameness are infrequently seen in cats but they are an important consideration when an obvious orthopaedic cause cannot be identified. Monoparetic cats are also frequently presented for veterinary investigation with the main complaint being lameness. CLINICAL CHALLENGES: Neurological causes of lameness may be difficult to determine without access to advanced imaging modalities, electrodiagnostics or cerebrospinal fluid analysis. AUDIENCE: This review, aimed at all veterinarians who treat cats, sets out to describe the specific approach to cats with lameness that cannot be attributed to an orthopaedic cause. It describes the diagnosis and management of the most common neurological conditions responsible for lameness or monoparesis in cats.     

Encephalo-myelopathy in young cats

Nineteen cats, aged three to 16 months, developed neurological signs including hindleg paralysis, head shaking, nystagmus, defective vision and reduced proprioception. Most of the animals were in cat colonies in research centres and were derived from specific pathogen-free stock. One was referred from veterinary practice. Over 40 per cent of litters could be affected constituting a serious commercial loss. Wallerian degeneration affected long tracts in the spinal cord and variously in the brain stem and cerebral white matter. In seven animals there was loss of Purkinje cells in the cerebellum and in eight there was neuronal loss in the spinal cord. Gliosis accompanied all changes. Although no viral agent was isolated the clinical pattern of the disease and evidence from other cases reported in the literature suggest an infectious cause.     

Intervertebral disc extrusion in six cats

Existing reports concerning intervertebral disc disease (IVDD) have focused almost exclusively on dogs, although a small number of individual case reports of IVDD of cats has been published. The medical records of six cats with IVDD were reviewed. Radiographic studies confirmed narrowed intervertebral disc spaces, mineralised intervertebral discs, and one or more extradural compressive lesions of the spinal cord in each cat. All disc extrusions were located in the thoracolumbar region. Surgical decompression of the spinal cord was achieved in all cats by means of hemilaminectomy and removal of compressive extradural material confirmed to be degenerative disc material. Good to excellent neurological recovery was noted in five of the six cats included in this report. Based on this review, it appears that IVDD of cats has many similarities to IVDD of dogs, and that healthy cats with acute intervertebral disc extrusion(s) respond favourably to surgical decompression of the spinal cord.     

Intramedullary spinal cord damage associated with intervertebral disk material in a dog

Intervertebral disk extrusions into the spinal cord are rarely reported in veterinary medicine, and only necropsy findings are described in previous reports. It is hypothesized that a disk lesion results in forceful injection of disk material into the spinal cord. In the 3-year-old Miniature Doberman Pinscher of our report, acute clinical signs and results of magnetic resonance imaging were consistent with this disease and helped determine the extent and character of the lesions. Alteration in the appearance of the nucleus pulposus was important in determining that intervertebral disk disease may have been present in this dog. However, a definitive diagnosis of intramedullary disk extrusion can be made only via histologic examination of a biopsy specimen or at necropsy. The dog improved substantially after surgical decompression of the spinal cord, and histologic findings in a biopsy specimen of material found within the spinal cord were consistent with mature degenerate intervertebral disk material.     

Hyperglycemic, hyperosmolar syndrome in feline diabetics: 17 cases (1995–2001)

Objective: The purposes of this study were to characterize the hyperglycemic, hyperosmolar syndrome (HHS), also known as nonketotic hyperosmolar diabetes, in cats; to determine the prevalence of HHS in the diabetic cat population in the emergency room; to document the outcome in cats with HHS; and to identify any predisposing factors or predictors of survival. Design: Retrospective study. Setting: An emergency service at a veterinary teaching hospital located in a major metropolitan area. Animals: The case records of 17 cats with hyperglycemic, hyperosmolar syndrome presenting from 1995 to 2001 were evaluated. An additional 37 cats with diabetic ketoacidosis and 80 cats with diabetes mellitus served as comparison groups. Interventions: None. Measurements and main results: Signalment, history, physical examination findings, clinico‐pathologic data, concurrent disease, and outcome were recorded. Hyperglycemic, hyperosmolar syndrome was seen in older cats that were often long‐standing diabetics receiving insulin for many months. Client concerns included polydipsia, polyuria, and lethargy. Neurologic and respiratory signs occurred frequently. Evaluation at presentation revealed profound dehydration, lactic acidosis, and azotemia. Serious concurrent diseases that likely contributed to the development of the HHS crisis were diagnosed in 88% (15/17) of the HHS cats. The most common concurrent diseases were renal failure, respiratory compromise, infection, congestive heart failure, neoplasia, and gastrointestinal tract disease. Pancreatitis and hepatic disease did not occur frequently in this diabetic cat population. Sixty‐five percent of HHS cats did not survive the initial hospitalization, with most dying or being euthanized within 10 hours of presentation. The long‐term survival rate was low (12%). Conclusions: HHS is a serious life‐threatening form of diabetic crisis and cats with HHS often have other severe systemic diseases. Cats with diabetes and concurrent disease, especially renal failure and congestive heart failure, are at increased risk of HHS and should be closely monitored for signs of crisis. The mortality rate for HHS cats is high.     

A field study of eight ovine vertebral body abscess cases

A vertebral body abscess extending into the epidural space causing spinal cord compression was diagnosed in the cervical spinal cord in four lambs and the thoracic spinal cord in four lambs. The affected lambs were aged between 4 and 10 weeks and clinical signs had been present for 7-21 days before veterinary examination. Treatment with high doses of penicillin did not result in an improvement of the neurological signs and all lambs were destroyed on humane grounds. Collection and analysis of cerebrospinal fluid (CSF) revealed a significant increase in the protein concentration in lumbar compared to cisternal CSF samples. There was a neutrophilic pleocytosis in two lumbar CSF samples. In lambs aged between 4 and 10 weeks with no history of previous locomotor dysfunction, paresis of more than 1 week duration may be suggestive of a vertebral body abscess which has extended into the epidural space causing spinal cord compression. Stagnation of CSF caudal to the lesion results in an increased protein concentration in the lumbar sample.     

Large interarcuate spaces in the cervical vertebral column of the tyrolean mountain sheep

Large interarcual spaces have been described between the arcus vertebrae C5/C6 and C6/C7 in the cervical vertebral column of Nubian goats. This aperture enables direct access to spinal cord and rootlets without the need to perform a hemilaminectomy. The present study was performed in order to determine whether these large interarcual spaces can also be found in the vertebral column of the Tyrolean mountain sheep, as this small ruminant, which is anatomically very similar to the Nubian goat, is frequently used for experimental purposes at the Surgical University Clinic in Austria. The carcasses of 10 sheep (six females, four males; range of age: 2.5-6 years, range of weight: 52-89 kg) were dissected and the vertebral column was exposed. All 10 sheep showed elliptic openings between the fourth cervical and the first thoracal vertebrae. Three sheep had additional openings between the first and the second thoracal vertebrae. All openings were covered solitarily by the ligamentum flavum and under this ligamentum lay the spinal cord without any further osseous or ligamentous protection. These findings are not mentioned in the common textbooks of veterinary anatomy and deserve attention, as they can be a step forward towards non-traumatic experimental surgery on the spinal cord.     

Presumptive Nocardia spp. infection in a dog treated with cyclosporin and ketoconazole

Abstract

CASE HISTORY: A dog that had received 8 months of cyclosporin and ketoconazole therapy for treatment of atopic dermatitis subsequently developed severe neurological disease, that failed to respond to treatment with trimethoprim-sulphadiazine and clindamycin.

HISTOPATHOLOGICAL FINDINGS: Histopathological examination of the pulmonary parenchyma and spinal cord revealed loose aggregates of Gram-positive, partially acid-fast, fine, beaded, filamentous bacteria, most consistent with Nocardia spp.

DIAGNOSIS: A presumptive diagnosis was made of disseminated nocardiosis of the spinal cord and lungs.

CLINICAL RELEVANCE: Nocardia spp. is an opportunistic actinomycete that may cause disseminated disease, particularly in immunocompromised animals. Cyclosporin is used in veterinary medicine to control immune-mediated and allergic disorders, with few reported adverse side effects. This case gives further evidence that involvement of the spinal cord in nocardiosis of the central nervous system (CNS) carries a poor prognosis, and opportunistic infection by Nocardia spp. may be a potential complication of immunosuppressive cyclosporin therapy in the dog.     

Veterinary Neurologic Rehabilitation: The Rationale for a Comprehensive Approach

The increase in client willingness to pursue surgical procedures, the heightened perceived value of veterinary patients, and the desire to provide comprehensive medical care have driven the recent demand of using an integrative treatment approach in veterinary rehabilitation. Physical therapy following neurologic injury has been the standard of care in human medicine for decades, whereas similar rehabilitation techniques have only recently been adapted and utilized in veterinary medicine. Spinal cord injury is the most common neurologic disease currently addressed by veterinary rehabilitation specialists and will be the primary focus of this review; however, research in other neurologic conditions will also be discussed. Of particular interest, to clients and veterinarians are techniques and modalities used to promote functional recovery after neurologic injury, which can mean the difference between life and death for many veterinary patients.The trend in human neurologic rehabilitation, often regardless of etiology, is a multimodal approach to therapy. Evidence supports faster and improved recoveries in people after neurologic injury using a combination of rehabilitation techniques. Although the primary neurological disorders researched tend to be spinal cord injury, peripheral neuropathies, allodynia, multiple sclerosis, and strokes—many correlations can be made to common veterinary neurological disorders. Such comprehensive protocols entail gait training activities in combination with neuromuscular electrical stimulation and directed exercises. Additionally, pain-relieving and functional benefits are bolstered when acupuncture is used in addition to rehabilitation. Studies, both laboratory and clinical, support the use of acupuncture in the management of neurologic conditions in small animals, specifically in cases of intervertebral disc disease, other myelopathies, and neuropathic pain conditions. Acupuncture’s ability to promote analgesia, stimulate trophic factors, and decrease inflammation, including neuroinflammation, make it an alluring adjunct therapy after neurologic injury.Although there is limited research in veterinary medicine on physical techniques that expedite recovery after neurologic injury, there are sparse publications on clinical veterinary research suggesting the benefits of acupuncture, rehabilitation, and LASER in dogs with intervertebral disk disease. Accordingly, due to the relative lack of evidence-based studies in veterinary neurologic rehabilitation, much of the data available is human or laboratory-animal based, however, evidence supports the utilization of an early, comprehensive treatment protocol for optimal neurologic recovery. The rationale for why an integrative approach is critical will be detailed in this review; in addition, literature on specific physical rehabilitation techniques that have evidence of improved recoveries after neurologic injury, will be addressed.     

Is there a link between bacteriuria and a reversible encephalopathy in dogs and cats?

Bacteriuria has been associated with abnormal neurological status in humans, especially geriatric patients. In this report, we review 11 cases (seven dogs and four cats) that suggest an association between bacteriuria and abnormal neurological status in veterinary medicine. These cases showed diffuse forebrain signs with or without brainstem signs, but primary brain disease was excluded by MRI and cerebrospinal fluid analysis. Bacteriological culture of urine was positive in each animal and neurological deficits improved or resolved with initiation of antibiosis ± fluid therapy and levetiracetam. While further studies are needed to definitively confirm or refute the link between bacteriuria and a reversible encephalopathy, urine bacteriological culture should be considered in veterinary patients presented with acute onset forebrain neuro-anatomical localisation, even in the absence of clinical signs of lower urinary tract inflammation.     

Chronic spinal epidural abscess in a cat: a case report with an unusual imaging finding

A 1-year-old domestic shorthair cat was evaluated for a chronic history of back pain, dysuria, and paraplegia. Radiographic and computed tomographic examinations showed circumferential widening of the vertebral canal at T13 and T14. A spinal epidural abscess (SEA) compressing the spinal cord from the level of T11 to L1 was suspected following intravenous contrast administration, and was confirmed by surgical exploration and histopathological analysis. The cat recovered its motor and bladder functions following surgical decompression and antibiotic therapy. SEA is a neurological emergency requiring prompt treatment. However, the present case had a prolonged disease course and pressure atrophy of the vertebrae was strongly suspected. To our knowledge, this imaging finding has not been reported in dogs or cats with SEA.     

Fibrocartilaginous embolic myelopathy in five cats

Five cats had clinical signs, radiographic findings, and cerebrospinal fluid analyses consistent with fibrocartilaginous embolic myelopathy. All cats had an acute onset of nonpainful, asymmetrical spinal cord signs (paresis or paralysis of one or more limbs). Magnetic resonance imaging was performed in three cats. On T2-weighted images, an intramedullary lesion was revealed that was hyperintense to normal spinal cord gray matter. On T1-weighted images, the lesion was isointense. Three of the cats were euthanized, and postmortem examination confirmed myelomalacia with intralesional fibrocartilaginous emboli. Two cats survived and were clinically improved within 3 weeks.