Widely distributed Bunina bodies and spheroids in a case of atypical sporadic amyotrophic lateral sclerosis.

We report the autopsy findings of an 81-year-old patient with short-course sporadic amyotrophic lateral sclerosis lasting approximately 5 months. Pathological findings were probably very early. Light microscopy showed abundant eosinophilic Bunina type inclusions widely distributed not only in the motor neurons of the spinal cord and brain stem but also in neurons of the Onuf's and Clarke's nuclei. Fine structural study revealed that the inclusions seen in the Clarke's nuclei were identical to Bunina bodies observed in anterior horn cells. A direct connection between axonal swelling and perikaryon was often seen in the facial and hypoglossal nuclei and in the spinal cord. Ubiquitin-positive Lewy body-like inclusions and central chromatolysis-like changes were also found in the anterior horn cells.