Intervertebral disc disease in Dachshunds radiographically screened for intervertebral disc calcifications

Background

Intervertebral disc disease (IDD) is a very common neurological disease, Dachshunds being the breed most often affected. In this breed, IDD has a hereditary background and is associated with intervertebral disc calcification (IDC), an indicator of severe intervertebral disc degeneration. In Finland, spinal radiography is used, when screening for IDC before breeding Dachshunds. We evaluated the association between IDC and IDD in Finnish Dachshunds radiographically screened for IDC.A questionnaire was sent to owners of 193 radiographically screened Dachshunds aged at least ten years. Clinical signs indicative of IDD were compared with IDC grade (grade 0 = no calcifications, grade 1 = 1 – 2 calcifications, grade 2 = 3 – 4 calcifications and grade 3 = 5 or more calcifications) and with age at the time of the radiographic examination. The diagnosis of IDD was confirmed by a veterinarian.

Results

IDD was common in the study population with 31% of dogs being affected. IDD and IDC were clearly connected (P < 0.001); IDD was rare in dogs with no calcifications (grade 0) and common in dogs with severe IDC (grade 3). The IDC grade was strongly positively associated with frequency of back pain periods (P < 0.001), and dogs with IDC grade 3 had frequent periods of pain. Reluctance to jump onto a sofa had a strong positive association with back pain. No association existed between age of the dog at the time of the radiographic examination and clinical signs indicative of IDD.

Conclusions

Radiographically detected IDC and IDD are common in Finnish Dachshunds and are strongly associated with one another. Spinal radiography is an appropriate screening tool for breeders attempting to diminish IDC and IDD in Dachshunds. A breeding program that screens dogs and selects against IDC can be expected to reduce the occurrence of IDD in future. Twenty-four to 48 months of age is a suitable age for screening.

Electronic supplementary material

The online version of this article (doi:10.1186/s13028-014-0089-4) contains supplementary material, which is available to authorized users.     

Lumbar cerebrospinal fluid in dogs with type I intervertebral disc herniation

BACKGROUND: Cerebrospinal fluid (CSF) in dogs with Hansen type I intervertebral disc herniation (IVDH) is classically described as normal or mildly inflammatory with a predominance of large mononuclear cells or neutrophils in severe acute herniations. However, we have observed a moderate to marked pleocytosis with a predominance of lymphocytes in some dogs with IVDH. HYPOTHESIS: Moderate to marked CSF pleocytosis occurs more commonly in dogs with type I IVDH than is reported in the literature. Lymphocytic predominance is more common than nonlymphocytic pleocytosis in dogs with chronic IVDH. ANIMALS: Four hundred twenty-three client-owned dogs with type I IVDH. METHODS: Retrospective study. Lumbar CSF of dogs with surgically confirmed type I IVDH was evaluated cytologically. Information obtained from medical records included signalment, prior clinical history, time from onset of signs to presentation, neurologic status, and intraoperative findings. Dogs with prior history and/or intraoperative evidence consistent with chronic IVDH before an acute herniation were termed acute-on-chronic (AOC). RESULTS: Pleocytosis (> 5 cells/uL) was present in 51% of dogs, including 23% with cervical IVDH and 61% with thoracolumbar IVDH. Moderate or marked inflammation (> or = 20 cells/uL) was identified in the CSF of 51% of dogs with thoracolumbar IVDH and pleocytosis. A predominance of lymphocytes was significantly more common in dogs examined > 7 days from onset of signs (P= .032) and in dogs with AOC IVDH (P= .0013). CONCLUSIONS AND CLINICAL IMPORTANCE: Moderate to marked CSF pleocytosis in dogs with type I IVDH is more common than previously reported. Lymphocytic pleocytosis is most common in dogs with chronic progression or AOC IVDH. Lymphocytic inflammation in the CSF of some dogs might suggest an immune-mediated response to chronically herniated disc material.     

Computed tomographic characteristics of acute thoracolumbar intervertebral disc disease in dogs

Forty canine patients with a presumptive diagnosis of the intervertebral disc herniation at the thoracolumbar region were imaged. A neurological examination was performed and all patients were classified under four grades by the examination. The degrees of attenuation of the herniated disc material were measured in Housefield units (HU) in each image. The ratio of the area to herniated disc material and the height to disc material were measured. The clinical grade was correlated with the area ratio of the herniated disc material to the spinal cord, but not correlated with the height ratio of that. In the patients with epidural hemorrhage at surgery, HUs of the herniated disc material was lower than those with no epidural hemorrhage at surgery. Non-contrast computed tomography scans of the spine can be useful in diagnosing acute intervertebral disc disease in chondrodystrophoid breeds, evaluating patient status and identifying concurrent epidural hemorrhage.     

Matrix metalloprotease-9 activity in the cerebrospinal fluid and spinal injury severity in dogs with intervertebral disc herniation

We investigated whether matrix metalloproteinase (MMP)-9 expression in the cerebrospinal fluid (CSF) of dogs with intervertebral disc herniation (IVDH) is associated with the severity of neurological signs and prognosis. CSF from the cisterna magna (C-CSF) and the lumbar spine (L-CSF) of 34 dogs with IVDH was analyzed using zymography. Activity of MMP-9 in L-CSF was detected in 6 of 34 dogs with IVDH, often for more than 7 days after injury. MMP-9 activity was not detected from any of the C-CSF samples. Of the six cases that were MMP-9 positive, all four cases with grade V that had loss of deep pain were non-ambulatory 6 months after treatment. The remaining two cases with grade III and IV could recover mobility. In dogs with grade V thoracolumbar IVDH, MMP-9 expression in the CSF may indicate severe spinal cord injury with poor prognosis.     

Transplantation of adipose derived mesenchymal stem cells for acute thoracolumbar disc disease with no deep pain perception in dogs

Thirty-four dogs with no deep pain perception due to acute thoracolumbar intervertebral disc disease underwent decompression surgery within 1 week of diagnosis. All dogs underwent hemilaminectomy. Adipose derived mesenchymal stem cells (AD-MSCs) were transplanted into the injured spinal cord parenchyma for the AD-MSCs transplant dogs. Long-term outcome was evaluated at the end of the follow-up period (> 6 months). AD-MSCs combination treatment showed better recovery outcomes compared to decompression surgery alone. These results indicate that this stem cell therapy is a potential therapeutic strategy to overcome the limitations of treatment for spinal cord injury in clinical medicine.     

Agreement between T2 and haste sequences in the evaluation of thoracolumbar intervertebral disc disease in dogs

The purpose of this study was to compare half-Fourier-acquisition single-shot turbo spin-echo (HASTE) and T2-weighted (T2-W) sequences in dogs with thoracolumbar disc extrusion. MRI studies in 60 dogs (767 individual intervertebral disc spaces) were evaluated. Agreement between T2-W and HASTE sequences was assessed for two criteria: presence of an extradural lesion and treatment recommendation. There was moderate agreement between T2-W and HASTE sequences as to presence of an extradural lesion (kappa = 0.575). HASTE was in agreement in 96.1% of the sites where no extradural lesion was identified on T2-W images, but only in 58.1% of the sites where extradural lesions were identified on T2-W images. There was also moderate agreement between T2-W and HASTE sequences as to treatment recommendations (kappa = 0.476). HASTE was in agreement in 98.4% of the sites where a lesion was considered nonsurgical on T2 but only 82.1% of sites a lesion was considered surgical on T2. In 1.0% of sites considered not surgical and in 9.8% of sites considered equivocal based on T2-W images, a surgical lesion was identified on HASTE. Acquisition of a HASTE sequence in addition to conventional sequences may be beneficial in determining the severity of spinal cord compression in some cases when evaluating the canine spine.     

Association of spinal cord compression seen on magnetic resonance imaging with clinical outcome in 67 dogs with thoracolumbar intervertebral disc extrusion

OBJECTIVES: To determine whether there is an association between the degree of transverse spinal cord compression detected by magnetic resonance imaging following thoracolumbar Hansen type 1 intervertebral disc disease in dogs and their presenting and postsurgical neurological status. METHODS: Medical records of 67 dogs with surgically confirmed Hansen type 1 intervertebral disc disease (2000 to 2004) were reviewed to obtain the rate of onset of disease, duration of clinical signs and presurgical and postsurgical neurological grade. Percentage of spinal cord compression was determined on transverse T2-weighted magnetic resonance images. Linear regression was used to examine the association between spinal cord compression and each of the above variables. Chi-squared tests were used to examine associations among postsurgical outcome and presurgical variables. RESULTS: Eighty-five per cent (57 of 67) of dogs were chondrodystrophoid. Mean spinal cord compression was 53 per cent (sd=219.7, range 14.3 to 84.9 per cent). There was no association between the degree of spinal cord compression and the neurological grade at presentation, rate of onset of disease, duration of clinical signs or postsurgical outcome, with no difference between chondrodystrophoid and non-chondrodystrophoid dogs. CLINICAL SIGNIFICANCE: The degree of spinal cord compression documented with magnetic resonance imaging in dogs with thoracolumbar Hansen type 1 intervertebral disc disease was not associated with the severity of neurological signs and was not a prognostic indicator in this study.     

Beta-2-microglobulin levels in the cerebrospinal fluid of normal dogs and dogs with neurological disease

BACKGROUND: Cerebrospinal fluid (CSF) analysis is the basis for establishing a diagnosis of central nervous system (CNS) inflammation. However, the information provided by routine CSF analysis is limited. Determination of CSF beta-2-microglobulin (beta2m) concentration has been used diagnostically in humans to identify inflammatory CNS disease; we hypothesized that it may have similar value in dogs. OBJECTIVES: The objective of this study was to measure (beta2m concentration in the CSF of clinically healthy dogs and compare the values to those observed in dogs with inflammatory CNS disease and intervertebral disc disease (IVDD). METHODS: CSF was collected from 10 clinically healthy laboratory dogs and 11 dogs each with inflammatory CNS disease and IVDD. Routine CSF analysis was performed, and (beta2m concentration was measured by ELISA. CSF (beta2m concentration and CSF:serum (beta2m ratio were compared between groups by ANOVA. Linear relationships between CSF total nucleated cell count (TNCC), RBC count, total protein concentration, and (beta2m concentration were assessed by regression analysis. RESULTS: The mean (+/- SD) CSF (beta2m concentration in clinically healthy dogs was 0.36 (+/- 0.05 microg/mL (cisternal) and 0.40 (+/- 0.07 microg/mL (lumbar). Median CSF (beta2m concentration in dogs with IVDD (0.46 microg/mL) and inflammatory CNS disease (0.85 microg/mL) differed from that of controls (0.36 microg/mL; P=.002). The concentration also differed between the 2 disease groups (P=.01). Five dogs with inflammatory CNS disease had CSF:serum (beta2m ratios >1. A correlation was identified between TNCC and (beta2m concentration (r=0.69, P=.0003). CONCLUSIONS: CSF (beta2m concentration is higher in dogs with IVDD and inflammatory CNS disease, with highest values seen with inflammatory disease. This may be attributed in part to the correlation between CSF (beta2m concentration and TNCC, but also may reflect intrathecal immune activation.     

Gastric mucosal lesions in dogs with acute intervertebral disc disease: characterization and effects of omeprazole or misoprostol

We characterized gastric mucosal lesions in dogs with acute degenerative disc disease treated by surgery and corticosteroid administration. The effect of omeprazole and misoprostol on gastric lesions in these dogs was also evaluated. Dogs were randomly assigned to 1 of 2 treatment groups or to the control group. Treatment consisted of omeprazole at 0.7 mg/kg orally once daily, or misoprostol at 2 microg/kg orally 3 times daily. All 3 groups received dexamethasone at 2 mg/kg on day 0, prednisolone at 2 mg/kg on day 1. prednisolone at 1 mg/kg on day 2, and prednisolone at 0.5 mg/kg on all further days (range, 5-6 days). Endoscopic examination was performed on day 0 and 5-6 days later. Four regions of the stomach were qualitatively scored from 1 to 12 based on the presence of submucosal hemorrhage, erosion, or ulceration, with ulceration receiving the highest numerical score. Nineteen of 25 dogs had gastric mucosal lesions at the beginning of the study. No significant difference was found in the gastric lesion score among the 3 groups at the end of the study. Gastric mucosal lesions were concluded to be common in dogs with acute degenerative disc disease treated with corticosteroids. Neither omeprazole nor misoprostol at the doses used was effective in healing or preventing the further development of gastric mucosal lesions.     

Chronic enteropathies in dogs: evaluation of risk factors for negative outcome

HYPOTHESIS: Certain variables that are routinely measured during the diagnostic evaluation of dogs with chronic enteropathies will be predictive for outcome and a new clinical disease activity index incorporating these variables can be applied to predict outcome of disease. ANIMALS: Seventy dogs were entered into a sequential treatment trial with elimination diet (FR, food-responsive group) followed by immunosuppressive treatment with steroids if no response was seen with the dietary trial alone (ST, steroid-treatment group). A 3rd group consisted of dogs with panhypoproteinemia and ascites (PLE, protein-losing enteropathy) that were treated with immunosuppressive doses of steroids. METHODS: Three years of follow-up information was available for all dogs. Clinicopathologic variables were tested for their ability to predict negative outcome, defined as euthanasia due to refractoriness to treatment. Different scoring systems including different combinations of these variables were evaluated using receiver operating characteristic (ROC) curves. RESULTS: Thirteen of 70 (18%) dogs were euthanized because of intractable disease. Univariate analysis identified a high clinical activity index, high endoscopic score in the duodenum, hypocobalaminemia (<200 ng/L) and hypoalbuminemia (<20 g/L) as risk factors for negative outcome. CONCLUSIONS AND CLINICAL IMPORTANCE: Based on the factors identified by logistic regression and ROC curve analysis, a new clinical scoring index (CCECAI) was defined that predicts negative outcome in dogs suffering from chronic enteropathies.     

Inflammatory cerebrospinal fluid analysis in cats: clinical diagnosis and outcome

The medical records of 62 cats with clinical signs of central nervous system disease and accompanying inflammatory cerebrospinal fluid (CSF) analysis were examined retrospectively to determine if signalment, clinical signs, CSF analysis and ancillary testing could accurately predict the type of central nervous system disease that was present. An inflammatory CSF was defined as one in which a total nucleated cell count was greater than 5 cells/microl or one in which the total nucleated cell count was normal but the nucleated cell differential count was abnormal. Sex, degree of CSF inflammation, neuroanatomical location and systemic signs provided little contributory information to the final diagnosis. In 63% of the cases a presumptive diagnosis could be made based on a combination of clinical signs, clinicopathological data and ancillary diagnostic tests. CSF analysis alone was useful only in the diagnosis of cats with feline infectious peritonitis, Cryptococcus species infection, lymphoma and trauma. Overall, despite extensive diagnostic evaluation, a specific diagnosis could not be made in 37% of cats. The prognosis for cats with inflammatory CSF was poor with 77% of cats surviving less than 1 year.     

The immunophenotype of blood and cerebrospinal fluid mononuclear cells in dogs

Inflammatory neurologic diseases are common in dogs, but establishing a definitive diagnosis often is difficult. Nucleated cell number and type in cerebrospinal fluid (CSF) rarely are suggestive of an etiologic agent. We speculated that CSF leukocyte immunophenotyping would be a useful adjunct in the investigation of canine inflammatory neurologic diseases by yielding more specific etiologic information. The goals of this study were to establish the feasibility of flow cytometric evaluation of individual canine CSF samples and to identify the cell distribution in healthy dogs. The mononuclear cell populations of paired blood and CSF samples from 23 healthy dogs were characterized by labeling of cells with antibodies against CD4, CD8alpha, CD21, and CD14 molecules and by flow cytometric analysis of their expression. The mean proportion of CD4+ and CD21+ cells was significantly higher in blood than in the CSF (P < .002 and P < .001, respectively). In contrast, the mean proportion of CD14+ and CD8a+ cells was not significantly different between blood and CSF (P = .5 and p = .9, respectively). These findings demonstrate differences in the distribution and function of mononuclear cells in the circulating venous and subarachnoid compartments in the dog.     

Correlation of plain radiographic and lumbar myelographic findings with surgical findings in thoracolumbar disc disease

The results of a prospective study to compare the plain radiographic and lumbar myelographic findings with the surgical findings in 70 cases of suspected thoracolumbar disc protrusion in the dog are reported. The aim was to assess the relative accuracy of disc lesion localisation using plain and contrast radiography. From the plain radiographs, the affected disc space was correctly identified in 40 cases (57.1 per cent), and incor- rectly identified in seven. More than one site was identified in 11; in eight of these dogs, the affect- ed disc space was strongly suspected. It was not possible to identify an affected disc in 12 cases. The site of disc protrusion was accurately identified by myelography in 60 dogs (85.7 per cent). In four dogs, myelography was helpful in identifying an adjacent disc and, in a further two, cord swelling was found at surgery. In one dog, neither disc material nor cord swelling was identified. Three myelograms were non-diagnostic.