A 14-year-old boy with an episode of acute weakness resembling acute demyelinating encephalomyelitis and polyradiculoneuritis after a febrile illness is described. Molecular analysis showed a mutation at codon 164 of the connexin 32 gene. Neuroradiological and neurophysiological follow-up is reported during acute and chronic phases of disease, suggesting that during metabolic stress connexin 32 mutations lead to a loss of normal cellular communication and reversible cell dysfunction in oligodendrocytes and in Schwann cells. These data confirm that altered gating properties of connexin 32 could give rise to acute, transient central and peripheral nervous system symptoms in situations of metabolic stress.