Aphasic status epilepticus presenting with prominent psychiatric symptoms: A case report

Background Aphasic status epilepticus (ASE) is a subtype of nonconvulsive status epilepticus characterized by aphasia as its primary ictal manifestation. Although psychiatric symptoms are uncommon in ASE, they may obscure the diagnosis when present. We report an atypical case, presenting predominantly with agitation and irritability, which was rapidly diagnosed as ASE by electroencephalography (EEG) based on the abrupt symptom onset and neurological history. Case Presentation A 49‐year‐old right‐handed woman with alcohol use disorder was referred to our psychiatric hospital because of agitation, irritability, and disorganized thinking. Approximately 2 months before presentation to our hospital, she developed a generalized tonic–clonic seizure 3 days after sustaining a head injury. A left posterior fossa subdural hematoma was diagnosed, and burr‐hole evacuation was performed at a general hospital. She continued rehabilitation; however, 6 days before admission to our hospital, she suddenly developed incoherent speech with agitation and irritability, prompting referral to our psychiatric hospital. Neurological examination revealed sensory aphasia. Given the history of brain injury and abrupt symptom onset, EEG was performed and demonstrated left‐dominant periodic lateralized epileptiform discharges, confirming ASE. Antiseizure treatment resolved the EEG abnormalities and aphasia; however, aphasia, agitation, and irritability recurred with periodic lateralized epileptiform discharges. The symptoms improved with intravenous diazepam, and no recurrence was observed for >2 years following optimization of antiseizure medication. Conclusion ASE may present predominantly with psychiatric symptoms and be misdiagnosed as a primary psychiatric disorder. Recognizing symptom chronology and epileptogenic background is essential for prompting EEG evaluation and early diagnosis.