Sporadic motor neuron disease with severe sensory neuronopathy.

We report a 62-year-old man with sporadic motor neuron disease (MND) of 52 months' duration with progressive sensory disturbance and high cerebrospinal fluid protein content. Neuropathologically, both the upper and lower motor neuron systems were severely affected, and light and electron microscopy revealed Bunina bodies and skein-like inclusions, which are characteristic of amyotrophic lateral sclerosis, in the remaining anterior horn cells. Moreover, there was severe degeneration without inflammatory infiltrates in the spinal posterior columns, spinal ganglia, and peripheral sensory nerves. These findings suggest that this case may be an unusual variant of sporadic MND with severe somatic sensory system involvement.