Aphasic status epilepticus: electroclinical correlation

Aphasic status epilepticus (ASE) in otherwise awake patients is a rare phenomenon. We present a series of nine consecutive patients with ASE to characterize clinical, electrophysiologic, and imaging findings.

Nine patients in ASE were identified between July 2006 and December 2009 at our institution. Each was evaluated by the neurology service and monitored with video-electroencephalography (EEG) for at least 24 h. Thorough, repeated language testing was correlated with EEG findings.

All nine patients were right-handed with subacute or chronic left hemispheric lesions on magnetic resonance imaging (MRI). All patients had mixed aphasia, three presenting with persistent aphasia from onset and six with episodic speech impairment, which became persistent in five of the six. The initial 30-min EEG demonstrated electrographic seizure in only five patients (56%), despite the presence of aphasia during the recording. Left hemispheric periodic lateralized epileptiform discharges (PLEDS) were seen in two patients, and left hemispheric slowing in two patients. Continuous video-EEG monitoring confirmed electrographic seizure activity in all nine patients. Peak electrographic seizure frequency varied from continuous to once every 2 h and was not associated with fluctuations in the speech deficit. EEG seizures resolved abruptly in three patients and gradually over up to 4 days in six patients. Clinical improvement was delayed in eight of the nine patients, and four patients retained some aphasia at discharge, 2-4 days after EEG seizure resolution.

Standard EEG is sensitive for detection of abnormalities in the dominant hemisphere in patients with ASE. However, continuous EEG is necessary to confirm the diagnosis and monitor treatment, since clinical symptoms do not correlate with electrographic seizure activity and do not provide sufficient information to guide treatment decisions.