Periventricular and subcortical leukoencephalopathy in two dachshund puppies.

Two wirehaired dachshund puppies were presented with generalized tremor and gait abnormalities characterized by mild ataxia, tetraparesis and slightly abnormal proprioception. Neurological examination led to the suspicion of a diffuse generalized white matter lesion. Computerized tomography and pathological examination revealed a remarkable unilateral dilatation of the lateral ventricles in each dog. Histopathological examination showed a severe reduction of stainable myelin, widespread mild perineuronal oedema with vacuolations and multifocal reactive astrocytosis affecting the subcortical and deep periventricular white, and to a lesser degree, grey matter of the cerebral hemispheres, most prominently at the level of the optic chiasm. Axons showed a moderately reduced packing density; some axons were irregularly shaped and slightly thickened. There was no evidence of myelin breakdown products and neurones appeared to be well preserved. Brain stem, cerebellum and spinal cord were normal, as was the peripheral nervous system. This leukoencephalopathy in two dachshund puppies most closely resembles human periventricular leukomalacia caused by pre- or perinatal hypoxia-ischaemia.