Atypical motor neuron disease with features of a multisystem degeneration: a non-familial case with prominent sensory involvement.

A 66-year-old male with no family history of neurological disease developed symmetrical paraesthesia, numbness and flaccid weakness of the hands and feet. Both the weakness and sensory loss became progressively more severe, and spread to involve the forearms and lower legs. Limb muscle wasting and tongue fasciculation only became apparent late in the disease course, and death eventually occurred from respiratory failure eight years after the onset of symptoms. Postmortem examination revealed most of the typical histological features of motor neuron disease, but in addition there was degeneration of the spinocerebellar tracts and spinal cord posterior columns, with degeneration and loss of their associated neuronal perikarya in Clarke's nuclei and dorsal root ganglia. The clinical and pathological features of this case suggest that it is a non-familial but atypical form of motor neuron disease, and support the concept that this disease represents part of a spectrum of neuronal degenerative processes rather than a circumscribed disorder limited to motor neurons.