Sung-Tsang Hsieh1,2

Guillain±Barre syndrome (GBS) is traditionally con-sidered to be a large-®bre neuropathy. However, the presence of hypo-aesthesia, dysaesthesia and dysauto-nomia in GBS patients raises the possibility that small-diameter sensory and autonomic nerves may also be affected. To investigate small-®bre neuropathy in GBS, we performed a skin biopsy from the distal leg of 20 patients with the demyelinating form of GBS. Skin sections were immunohistochemically stained with anti-serum against protein gene product 9.5 (PGP 9.5), a ubiquitin C-terminal hydrolase. Cutaneous innervation was evaluated by measuring epidermal nerve density (END), and END was further correlated with various clinical and electrophysiological parameters. In GBS patients, END values were much lower than in age- an