Ultrastructure of sural nerve in a case of arsenical neuropathy.

Abstract

Examination of electron microscopical and teased preparations of a biopsied sural nerve from a patient with arsenical neuropathy is reported. Teased preparations and toluidine blue stained epon sections showed a decrease in the number of myelinated fibres and Wallerian degeneration. Electron microscopy revealed destruction of myelin sheaths, further disintegration associated with degeneration or disappearance of myelinated axons and numerous degenerative changes in the Schwann cell cytoplasm. There was no evidence of segmental demyelination. Occasional onion-bulb-like structures, however, associated with proliferation of Schwann cells, were observed. Obvious elongation of the basement membrane, except in an onion-bulb-like structure, or collagen fibril proliferation or evidence of phagocytosis was not found. These findings are considered to correspond mainly with Wallerian degeneration. Some consideration as given to the unusual onion-bulb-like structures.