[Mitochondrial encephalomyopathies and West's syndrome: a frequently underdiagnosed association].

Introduction: West's syndrome is known to have symptomatic, cryptogenetic and idiopathic forms. Greater knowledge of the different pathologies and the development of new diagnostic techniques have allowed the list of symptomatic forms to be extended and congenital disorders of the metabolism account for a significant percentage as an aetiopathogenic factor. Yet, although it is known that mitochondrial cytopathies can trigger the development of West's syndrome, few reports exist concerning their association.