Vestibular disease in dogs: association between neurological examination, MRI lesion localisation and outcome.

OBJECTIVES: To determine whether the neurological examination correctly distinguishes between central and peripheral vestibular lesions in dogs. MATERIALS AND METHODS: Retrospective study on dogs with vestibular disease presenting to two referral clinics in Germany. RESULTS: Ninety-three dogs were included; neurological examination suggested central vestibular disease in 62 and a peripheral lesion in 31. MRI diagnosis was central vestibular disease in 68 dogs and peripheral in 25. Of the 62 dogs with a lesion localisation diagnosed as central vestibular by neurological exam, 61 were correctly identified (98.4%). Twenty-four of the 31 dogs diagnosed with a peripheral lesion by neurological exam had a consistent lesion on MRI (77.4%). CLINICAL SIGNIFICANCE: The neurological examination is efficient at identifying lesions in the central vestibular system but less so for peripheral lesions. Therefore it is prudent to recommend imaging in dogs that show signs of peripheral vestibular syndrome but do not rapidly respond to treatment.

[Evaluation of decreased glucose levels in the cerebrospinal fluid of dogs]. / Untersuchungen zu erniedrigten Glukosewertenim Liquor cerebrospinalis des Hundes.

OBJECTIVE: The aim of the study was to evaluate the glucose ratio (glucose level in the cerebrospinal fluid [CSF]/blood glucose level) as a quickly available marker for detecting bacterial meningoencephalomyelitis (BM). MATERIAL AND METHODS: Blood and CSF samples of 328 dogs were reviewed and evaluated retrospectively. Following the neurological diagnosis, the dogs were assigned to seven different groups: steroid-responsive meningitis-arteritis (SRMA), intervertebral disc disease (IVDD), neoplasia of the central nervous system (N), idiopathic epilepsy (IE), bacterial meningoencephalomyelitis (BM), meningoencephalomyelitis of other origin (ME) and healthy dogs. RESULTS: The median of the CSF-glucose level (mmol/l) and the median of the glucose ratio in the SRMA group displayed the lowest values and differed significantly from the CSF-glucose levels of dogs in the groups IVDD, N, IE and healthy dogs (CSF-glucose level: p<0.01; glucose ratio: p<0.05). In the BM group, both parameters did not differ significant- ly from other groups, but displayed similar low levels as in the SRMA group. There was a negative correlation between the CSF cell count and the CSF-glucose ratio (Spearman correlation coefficient -0.322, p=0.01, R²=0.108). CONCLUSION: The CSF-glucose concentration cannot be used as a distinct marker to differentiate BM from other inflammatory CNS-diseases, especially from SRMA usually accompanied by severe pleocytosis. Low CSF-glucose levels appear to be caused by elevated CSF cell counts rather than by bacterial metabolism. CLINICAL RELEVANCE: For a definitive diagnosis of bacterial meningoencephalomyelitis in dogs, the detection of microorganisms remains necessary.