An autopsy case of sporadic amyotrophic lateral sclerosis with 16-year survival without artificial ventilation

An autopsy case of a 65-year-old male diagnosed as having classic amyotrophic lateral sclerosis (ALS) and who survived for 16 years without artificial ventilation is described. The progression of the disease was remarkably slow, and the bulbar and respiratory functions remained relatively well preserved. Pathologically, both upper and lower motor neurons were affected, the latter much more than the former. The volume of the spinal anterior horn of the fourth cervical cord (C4) was relatively well preserved compared to those of the thoracic cords, which were the most severely affected. This preservation of C4 may have been compatible with the relatively good preservation of respiratory muscle. Despite the long clinical course, the involvement was restricted to the motor and related systems, which was compatible with classic ALS. However, this case was distinctive in the lack of myelin pallor and the absence of macrophages in the pyramidal tracts, where large myelinated fibers were markedly decreased. Further-more, no identification was made of any Bunina bodies or skein-like inclusions despite a survey of almost the entire spinal cord. No abnormalities were found in superoxide dismutase 1 complementary DNA sequences. Among the previously reported long surviving cases, certain cases showed relatively uniform neuropathologic findings including the lack of Bunina bodies and macrophage activation in the pyramidal tracts. Such cases as well as ours may represent a form of ALS. Further study is required to determine the significance of these long sur-viving cases for understanding the pathomechanisms underlying motor neuron diseases.