A four-year old female Rottweiler was presented for examination because of a progressively worsening locomotor abnormality of a 4-month duration. Ataxia of all four limbs was noted initially, followed by tetraparesis and difficulty rising and standing. On clinical examination the dog appeared alert and exhibited signs of UMN tetraplegia, suggestive of a focal or diffuse white matter cervical spinal cord lesion. No further clinical abnormalities involving other organs and systems were noted. Ancillary diagnostic investigation (CBC, serum biochemistry, urinalysis, radiography of the cervical spine) did not reveal any abnormalities. Cervical myelography showed attenuation of the subarachnoid contrast columns at the level of the fifth cervical vertebra, compatible with the presence of an intradural-intramedullary space-occupying mass. Cerebrospinal fluid examination was normal. MRI revealed a 25 mm long fusiform expansion of the cord at the level of the fourth and fifth cervical vertebrae, where an abnormally high signal in T2-weighted images was detected. The lesions were focal and restricted to the white matter, without loss of distinction between gray and white matter. Due to the severe, incapacitating neurological dysfunction and the poor overall prognosis, the owner of the dog elected euthanasia and gave permission for necropsy. On gross post mortem examination a focal enlargement of the spinal cord was noted, involving the fourth and fifth cervical segments. Histopathology findings were limited to the white matter, where a widespread demyelinating process extending rostrally into the brainstem and caudally into the thoracic spinal cord segments was observed. In some areas demyelination was advanced, leading to the formation of microscopic cavities in the spinal cord parenchyma. Further pathology findings included reactive astrocytosis and gliosis. A histopathological diagnosis of leukoencephalomyelopathy was made, based on the characteristic white matter lesions and the absence of evidence suggestive of inflammatory or neoplastic disease.
Differential diagnosis of cervical spinal cord disease in young adult Rottweilers includes vertebral malformation-malarticulation, diskospondylitis, myelitis, neoplasia and idiopathic disorders reported to occur in this breed, such as neuroaxonal dystrophy and leukoencephalomyelopathy. In this case, imaging findings were compatible with the presence of an intraparenchymal lesion and therefore differential diagnosis included intramedullary neoplasms and focal granulomatous myelitis. Leukoencephalomyelopathy commonly appears in young adult dogs (1.5-4 years old) as cervical spinal cord disease with mild initial signs that progress slowly. However, in the reported cases imaging studies were normal and not compatible with a space-occupying lesion as in the presented one.