Recent developments in the management of peripheral neuropathy using skin biopsy

Skin biopsy has become a widely used tool to investigate small calibre nerve fibres in peripheral neuropathies. This technique is safe, minimally invasive, painless, easy to perform, and cheap. It provides diagnostic information in patients with small fibre neuropathy in whom routine neurophysiological tests are commonly normal. Moreover, it allows investigating the innervation of sweat glands, thus giving information on the autonomic nervous system. Biopsy of the hairy skin is used to investigate unmyelinated and small myelinated fibres, whereas biopsy of the glabrous skin can be taken to examine large myelinated fibres. The applications of skin biopsy for diagnostic and research purposes cover the spectrum of peripheral nervous system diseases, from painful axonal neuropathies to sensory neuronopathies and immune-mediated and inherited demyelinated neuropathies. Finally, studies on axon regeneration in human and experimental models suggest that skin biopsy has a potential usefulness to monitor the progression of neuropathy and the efficacy of neuroprotective treatments.