Atonic SE has been reported in patients with LGS but seems less common than nonconvulsive or TSE in that syndrome. It appears as “an inability to maintain the upright position, due to repetitive seizures or to serial head drops when the patient is sitting, without interictal clouding of consciousness” [4]. Two patients with discontinuous SE characterized by repetitive asymmetric atonic episodes associated with diffuse but asymmetric spike-waves have been reported in the literature [38]. Both patients had focal seizures and interictal rolandic discharges on EEG.

It should be noted that children with certain epilepsy syndromes might present with other types of prolonged seizures that mimic atonic SE, such as repeated atypical absences or nonconvulsive SE. An example is epilepsy with myoclonic astatic seizures, in which myoclonic, atonic/astatic, myoclonic astatic, and atypical absences may be observed and repeated long enough to suggest atonic SE [39]. These events are often difficult to diagnose, especially in children with intellectual disability, in whom impairment of consciousness and hypotonia are often attributed to other causes such as medication side effects.