Skin changes in patients with amyotrophic lateral sclerosis: light and electron microscopic observations.

Patients with amyotrophic lateral sclerosis are usually confined to bed within a few years from the onset of the disease; however, bedsores are not known to develop even at its terminal stages. In this study, skin from patients with amyotrophic lateral sclerosis, neuromuscular diseases other than amyotrophic lateral sclerosis, and nonneurologic disorders has been examined by light and electron microscopy for morphologic changes in the connective tissue. On physical examination of the skin in amyotrophic lateral sclerosis patients, the stretched fold showed a delayed relaxation phase. On light microscopy, collagen bundles in the dermis were disoriented, separated, and fragmented, especially in the papillary dermis. Ultrastructurally, extensive deposits of amorphous, fine granular material in the ground substance compartment of the dermis were observed. The preceding cutaneous changes became more apparent as the disease advanced. We speculate that the deposition of this amorphous material may play the role of pressure absorber, thus preventing the occlusion of blood vessels.