Juvenile absence epilepsy relapsing as recurrent absence status, mimicking transient global amnesia, in an elderly patient

We describe a 68-year-old woman who had typical absence seizures since 14 years of age. The absences were refractory to treatment and persisted into adulthood, with no seizure-free periods until seizure control at 59 years of age. After six years of being seizure-free, she presented with an episode characterized by mental confusion, abnormal behaviour, and amnesia, lasting for several hours. An EEG performed the day after, when the patient had already recovered, was unremarkable. The episode was interpreted as transient global amnesia. After two and three years, respectively, she presented with two analogous episodes lasting >24 hours. An EEG disclosed, on both occasions, subcontinuous generalized spike-and-wave discharges, consistent with absence status epilepticus (AS). The last episode occurred at 68 years of age and was successfully treated with intravenous lorazepam. After one month of follow-up, no further episodes occurred. AS is common in juvenile absence epilepsy, however, our patient showed a rather atypical course, characterized by refractory and persistent absences during adolescence and adulthood, and a tendency for AS to recur with no more absences in later life. Despite the known epilepsy history, AS episodes were initially misdiagnosed. Moreover, EEG recording and subsequent treatment were not performed until the second day of status.