Clinicopathologic Features of Two Patients With Sporadic Amyotrophic Lateral Sclerosis Who Maintained Communication Ability for Over 30 Years.

We report the clinicopathologic features of 2 unrelated patients with sporadic amyotrophic lateral sclerosis (SALS) supported by tracheostomy and invasive ventilation (TIV) who were able to maintain communication ability for more than 30 years after disease onset. In both cases, the age at onset was younger than the mean, initially the progression of muscle weakness was consistent with that in the majority of SALS patients, and TIV became necessary several years after disease onset. Thereafter, however, their neurologic deterioration slowed and the patients were able to operate computers by facial movements for several decades. At autopsy, neuronal loss appeared to be confined to the motor neuron system. Furthermore, while Betz cells and lower motor neurons in the spinal anterior horns and hypoglossal nucleus were severely depleted, other pyramidal neurons in the motor cortex, and lower motor neurons in the other brainstem motor nuclei were retained. Neuronal and glial cytoplasmic inclusions immunoreactive for phosphorylated 43-kDa TAR DNA-binding protein (TDP-43) were evident in the CNS, but in extremely small numbers. The present patients may represent a distinct subgroup of patients with SALS who are able to maintain communication ability for an extremely long period, accompanied by very mild TDP-43 pathology.