• amyotrophic lateral sclerosis;
  • axonal spheroids;
  • motor neuron disease;
  • ubiquitin-positive dense bodies

An autopsy case of motor neuron disease in which only the upper motor neurons were involved is reported. A 64-year-old man presented with progressive dysarthria, dysphagia and spastic quadriparesis with no muscle atrophy or fasciculation. He became bedridden 1.5 years later and died of pneumonia 3 years and 3 months after onset. Neuropathological findings consisted of a decreased number of Betz cells in the motor cortex and degeneration of the pyramidal tracts in the brainstem and spinal cord. The motor nuclei of the brainstem and anterior horn cells in the spinal cord were preserved. Some anterior horn cells contained ubiquitin-positive dense bodies. Many axonal spheroids were found in the pyramidal tract in the brainstem, most frequently in the cerebral peduncles of the midbrain. These clinicopathological features are in keeping with primary lateral sclerosis as previously reported, however, the presence of ubiquitin-positive material in some anterior horn cells suggests there may be some motor nerve cell degeneration occurring simultaneously.