[Nerve biopsy].

Nerve biopsy, if undertaken at centres with appropriate expertise, may be a valuable diagnostic procedure in selected patients with peripheral neuropathy. Sural nerve biopsy and skin biopsy for evaluation of epidermal nerves are described. Indications, surgical procedure, preparation and transport are reviewed. Usually the patient has to be admitted to a hospital with the necessary resources for a comprehensive battery of nerve tissue processing, including teasing and electron microscopical examination, and other investigative procedures. Another option, when practically and economically feasible, is to obtain sural nerve biopsy from several (2-4) patients performed by a skilled surgeon at the local (central) hospital. A technician from a neuromuscular centre or laboratory of neuropathology should be at the site to provide immediate and proper preparation and transport of the tissue samples. An example of peripheral nerve vasculitis with teased nerve fibers in early and late axonal degeneration is presented as an illustration. Sural nerve biopsy is useful in selected cases, particularly in order to demonstrate peripheral nerve vasculitis. For detection of small fiber neuropathy in the investigation of painful neuropathies, skin biopsy for evaluation of epidermal nerves may be an appropriate alternative.