[Carbamazepine-sensitive neuromyotonia and Charcot-Marie-Tooth disease of the neuronal type].

Following an anti-smallpox vaccination a 17 year-old boy developed spontaneous muscular activity with cramps and fasciculations in the lower limbs. There was distal amyotrophy of the lower limbs and pes cavus. Clinical signs suggested a cholinergic hyperfunction. EMG showed a significant spontaneous activity and was neurogenic in the lower limbs. Nerve conduction velocities were consistent with axonal damage. Muscular biopsy showed aspects of chronic denervation. Neuromyotonia disappeared with carbamazepine treatment. This case can be added to the reported associations of neuromyotonia and Charcot-Marie-Tooth disease. Such cases are an additional argument for the axonal origin of neuromyotonia.