Absence status epilepsy: a case report and literature review / 中华神经科杂志

ABSTRACT

Objective:To improve the knowledge of clinicians about absence status epilepsy (ASE).Methods:The ictal clinical manifestations, the interictal and ictal phase electroencephalogram (EEG) characteristics of 1 patient with ASE in the Department of Epilepsy, Beijing Tiantan Hospital, Capital Medical University on November 20, 2022 were analyzed, and the pathogenesis, clinical and EEG characteristics, differential diagnosis, treatment experience of ASE were summarized by retrospective analysis combined with previous literature review.Results:The patient was a 38-year female, with onset age of 18 years. The main clinical manifestations were repeated prolonged decline of consciousness with generalized tonic-clonic seizures. The long-range video EEG showed generalized spike-slow wave and slow wave sporadic in the interictal period, and continuous or sub-continuous 2.5-3.0 Hz generalized spike-slow wave discharge in the ictal period, and the laboratory and imaging findings were normal. A total of 17 patients consistent with ASE diagnosis were reported in 7 English literatures, and there were totally 18 cases (including this patient) analyzed in this paper. ASE is a specific subtype of idiopathic generalized epilepsy (IGE). The ratio of male to female was 1∶1. The onset age of 16/18 patients was in youth to middle age, and the average onset age was 25.3 years. Absence status epilepticus was the representative or main seizure type, and 15/18 patients presented with infrequent generalized tonic-clonic seizures, no independent myoclonic seizures were found. The interictal EEG showed generalized or incomplete generalized spike-wave or poly spike-wave discharges around 3.0 Hz under normal background, and may have focal non-localizing discharges. The ictal EEG presented as continuous or sub-continuous rhythmical or non-rhythmical≥2.5 Hz (mainly 2-4 Hz) generalized spike or poly spike-wave discharges. ASE mainly needed to be distinguished from de novo late-onset absence status epilepticus, adult IGE with phantom absences. The first choice of drugs included valproate sodium and lamotrigine. The correct drug selection resulted in better prognosis. Conclusions:ASE is clinically rare. By far, its pathogenesis is not well understood. ASE can easily be misdiagnosed as non-epileptic or focal seizure. For patients with late onset, infrequent generalized tonic-clonic seizures who are clinically consistent with IGE, ASE is necessary to be vigilant when there are long-term changes in consciousness, response ability and behavior. Long-term video EEG monitoring should be perfected in time to avoid misdiagnosis and mistreatment.