Thyrotoxic neuropathy (Basedow's paraplegia).

Polyneuropathy is a rare but possible manifestation of severe hyperthyroidism. The patient reported here developed a polyneuropathy affecting mostly leg muscles (Basedow's paraplegia) during the course of severe thyrotoxicosis. The polyneuropathy was confirmed with sequential electrophysiological studies of nerves and muscles and by muscle biopsy. The involvement of the proximal leg muscle is also interpreted as a neuropathic or nerve-mediated process rather than a concomitant thyrotoxic myopathy.