Burst Suppression Patterns on an Electroencephalogram of an Infant with Congenital Central Hypoventilation

Abstract

We read with great interest the recent case report by Hong et al 1 describing an infant with congenital central hypoventilation syndrome who displayed burst suppression patterns on the electroencephalogram (EEG). The patient in the report developed apnea at the age of 2 days, and had spasms during sleep when she was age 1 month. The EEG performed at that time showed a typical burst suppression (BS) pattern. As the authors noted in the case study, BS patterns on the EEG imply severe central nervous system dysfunctions including coma, cerebral anoxia or childhood epileptic encephalopathy. Early infantile epileptic encephalopathy (EIEE, Ohtahara syndrome) and early myoclonic epilepsy (EME) are representative examples of conditions associated with the BS pattern. These syndromes share several clinical manifestations and are characterized by the early onset of seizures, BS patterns on the EEG, and poor prognosis with severe psychomotor retardation. 2 However, the etiologiesandseizuretypesaresomewhat different between EIEE and EME. The majority of EIEE patients have brain malformations, and many cases of EME are associated with metabolic disorders such as nonketotic hyperglycinemia. EIEE cases typically present with tonic seizures, which is similar to the patient in the cited report, while EME is likely to be associated with myoclonic seizures. However, the BS pattern that presented only during sleep and normal waking EEG in this patientsuggestsEMEratherthanEIEE.Althoughtheclinicalseizures mimicked EIEE in this patient, the EEG findings more favored EME. It is often difficult to clearly differentiate between the two syndromes.