Single-Epileptic Spasms with or without Hypsarrhythmia: A Study of 16 Patients

Abstract

Objective We evaluated the electroclinical features, etiology, treatment, and outcome of 16 patients with single-epileptic spasms (ESs) with or without hypsarrhythmia (WoH). Methods Nine boys and seven girls had single-ESs. ESs were considered as single epileptic spasm variants when no other spasm occurred for 1 minute before and after each spasm. Age at the onset of ESs was between 2 and 84 months, with a mean age of 11 months. Results We recognized a group of 15 patients with single-ESs as the main type of seizure; 6 patients with WoH and 9 patients with hypsarrhythmia, respectively. Nine of these 15 patients had other types of seizures before the onset of single-ESs, and 12 patients had other types of seizures during the period in which the ESs occurred. Nine of 15 patients had a structural and seven had an unknown etiology. In 10 cases, the ESs were refractory to antiepileptic drugs, while 4 patients responded well to adrenocorticotropic hormone (ACTH), 1 to pyridoxine, and 2 to the ketogenic diet (KD). The remaining patient (patient.16) had single-ESs and electroclinical features of Lennox–Gastaut syndrome (LGS). Conclusion In this article, we present a series of infants who had daily single-ESs with or WoH. Those with single-ESs with hypsarrhythmia evolved to an epileptic encephalopathy. Video-electroencephalogram (EEG) and polygraphic-EEG recordings are crucial to identify the single-ESs.