Electrophysiological signs of peripheral nerve dysfunction in progressive myoclonus epilepsy

Electrophysiological findings were analysed in a group of 24 patients with progressive myoclonus epilepsy (PME) without Lafora bodies. Denervation activity in needle EMG and diminution of motor and sensory responses pointed out a mild axonal degeneration. We observed a significant slowing of motor and sensory conduction velocities in all the limb nerves examined, but distal motor latencies were not significantly increased. H-reflex latency of the posterior tibial nerve was prolonged. These results yielded the suggestion that there is a systemic peripheral nerve membrane dysfunction in PME.