Epilepsy Syndromes in Infancy
Christian M. Korff, MD and Douglas R. Nordli, Jr., MD
An increasing number of infantile epilepsy syndromes have been recognized. However, a significant number of infants (children aged 1-24 months) do not fit in any of the currently used subcategories. This article reviews the clinical presentation, electroencephalographic findings, evolution, andmanagement of the following entities: early infantile epileptic encephalopathy, early myoclonic epilepsy, infantile spasms/West syndrome, severe myoclonic epilepsy of infancy, myoclonic-astatic epilepsy, generalized epilepsy with febrile seizures plus, malignant migrating partial seizures of infancy, hemiconvulsions-hemiplegia-epilepsy, benign myoclonic epilepsy, and benign familial/nonfamilialinfantile seizures. Issues related to their classification are addressed. © 2006 by Elsevier Inc. All rights reserved. Korff CM, Nordli Jr DR. Epilepsy syndromes in infancy. Pediatr Neurol 2006;34:253-263. ognized as such by the majority, thanks to the recent developments in diagnostic techniques, such as videoelectroencephalography, brain imaging, and cytogenetics. However, despite this remarkableprogress, up to a quarter of infants with epilepsy do not fit in any of the proposed syndromes, or are classified into broad and unspecific categories . It is likely that additional entities are waiting to be defined in this age group . This article reviews the clinical characteristics, electroencephalographic findings, evolution, and management of the infantile epileptic syndromesidentified in infancy so far. Their main features are summarized in Table 1, and specific treatment options for some of them are presented in Table 2. Issues related to their classification are addressed at the end of the review, and suggestions for further improvements in the classification of infantile epilepsies are proposed. Early Infantile Epileptic Encephalopathy With Suppression-Burst (OhtaharaSyndrome) Early infantile epileptic encephalopathy, or Ohtahara syndrome, is a severe neurologic condition first described in 1976 . It is a rare entity, with a relative prevalence to West syndrome estimated at 1/40 or less . It is characterized by epileptic tonic spasms and a suppression-burst electroencephalogram (Fig 1). The suppression-burst pattern is present in both waking and sleepingstates, and appears in the first 3 months of life . Partial tonic seizures can be observed, but myoclonic seizures are rare . Etiology is heterogeneous, and includes brain malformations, migration disorders, mitochondrial diseases, and, rarely, inborn errors of metabolism, such as Leigh’s disease or cytochrome oxidase deficiency [9,10]. The seizures are usually intractable to antiepilepticmedications, and the developmental prognosis is uniformly poor . Surgery can be considered in those patients with cortical malformations, such as cortical dysplasia or hemimegalencephaly. Ohtahara syndrome frequently evolves
Introduction An accurate diagnosis is considered the first and most critical step in the management of pediatric epilepsy [1,2]. Delineating epilepsy syndromes serves thatpurpose. In addition to improving communication between caregivers and establishing clear criteria for research studies, epilepsy syndromes can suggest underlying disease pathophysiology, provide prognostic information to the families, and aid in the selection of appropriate diagnostic tests. Epilepsy syndromes are the rational basis for selection of appropriate antiepileptic drugs, surgicalprocedures, or alternative treatment options [1,3,4]. The epilepsy syndrome classification system adopted by the International League Against Epilepsy in 1989  has been demonstrated to be reliable and applicable to children [6,7]. Moreover, an increasing number of infantile (1-24 months) epileptic syndromes are being isolated and rec-
From the Epilepsy Center, Children’s Memorial Hospital,...