Epileptic encephalopathies refer to a group of disorders in which the unremitting epileptic activity contributes to severe cognitive and behavioral impairments above and beyond what might be expected from the underlying pathology alone, and these can worsen over time leading to progressive cerebral dysfunction. Several syndromes have been described based on their electroclinical features (age of onset, seizure type, and EEG pattern). This review briefly describes the clinical evaluation and management of commonly encountered epileptic encephalopathies in children. 1. Introduction The term “epileptic encephalopathy” refers to a group of disorders in which the unremitting epileptic activity contributes to progressive cerebral dysfunction. This cannot be explained by the underlying etiology alone [1]. It may be progressive or have waxing-waning course. The underlying etiology is diverse. Their clinical and electroencephalographic (EEG) features mirror the specific age-related epileptogenic reaction of the immature brain. The various syndromes of epileptic encephalopathy are tabulated in Table 1. This review will briefly discuss the diagnosis and management of these syndromes according to the age of onset. Table 1: Epileptic encephalopathies. 2. Early Infantile Epileptic Encephalopathies This group of disorders comprises Ohtahara syndrome or early infantile epileptic encephalopathy (EIEE), early myoclonic encephalopathy (EME), and malignant migrating partial seizures in infancy. Ohtahara syndrome is a devastating epilepsy with onset ranging from intrauterine period to 3 months of age. The tonic spasms are the defining seizure type which are very frequent and occur in both sleep and wakeful states. Besides these, partial and rarely myoclonic seizures may be observed. The interictal EEG shows burst suppression pattern with no sleep-wake differentiation. The bursts last for 2–6 seconds alternating with periods of suppression lasting for 3–5 seconds. The underlying causes are heterogenous. The majority of cases are attributable to static structural brain lesions such as focal cortical dysplasia, hemimegalencephaly, and Aicardi syndrome [2, 3]. Few genetic mutations have been described but these are not specific for Ohtahara syndrome [4, 5]. These include mutations in the syntaxin binding protein-1 (STXBP-1) [6], Aristaless-related homeobox (ARX) [7], and SLC25A22-gene encoding a mitochondrial glutamate carrier [8]. An epileptic encephalopathy similar to Ohtahara syndrome, attributable to mutations in the KCNQ2 gene that encodes the voltage-gated potassium
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