Electrophysiological evidence by single fibre electromyography of neuromuscular transmission impairment in a case of Miller Fisher syndrome

Miller Fisher syndrome is an autoimmune neuropathy characterised by ataxia, areflexia and ophthalmoplegia, with minimal if any limb weakness, and in the majority of cases by high titres of IgG anti-GQ1b ganglioside antibodies. In vitro electrophysiological experiments have demonstrated that these antibodies induce a transmission blockade at neuromuscular junction either pre- or post-synaptically. We report the case of a 63-year-old man with MFS that shows blood serum negative for anti-GQ1b but presents an impairment of neuromuscular transmission detected by single fibre electromyography. To the best of our knowledge, this represents the first case in the literature using jitter technique and suggests that other antibodies may be involved in the function of motor end plates by bindings to the synaptic membranes.