The Ongoing Challenge of Diagnosing Non-convulsive Status Epilepticus: What About Generalized Non-reactive Rhythmic Alpha Activity in the Salzburg Criteria?

Abstract

The ILAE Task Force on Classification released a report in 2015 to clarify the classification of status epilepticus. Non-convulsive status epilepticus (NCSE) was defined as SE without prominent motor symptoms, with or without coma. This diverse entity’s electrophysiological diagnosis, which is more consistent in clinical recognition, may be challenging. Some classifications and revisions have been proposed recently, making NCSE diagnosis easier. There are, however, patients who remain in the ‘grey zone’. The increasing evidence in patients, who do not meet the Salzburg Consensus Criteria for NCSE diagnosis of ‘NCSE’ or ‘possible NCSE’, but whose clinical and electrophysiological features are still suspicious for NCSE, may pave the way for developing more comprehensive criteria. Therefore, we present here the ‘generalized non-reactive alpha activity’ in the electroencephalogram (EEG) of an elderly patient with no known epilepsy before, who presented with acute confusional state of unexplained cause, which we suspected as NCSE and managed a ccordingly with success. Considering that ‘time is brain’, early and correct NCSE diagnosis is critical and the NCSE EEG criteria should be more inclusive for the patients in the ‘grey zone like the one presented here with ‘generalized non-reactive alpha activity’.

Keywords

• non-convulsive status epilepticus
• alpha rhythm
• salzburg criteria
• grey zone
• generalized non-reactive alpha activity