EEG Screening for Temporal Lobe Epilepsy in Patients With Acute Psychosis

Abstract

Seizures may present with ictal or interictal psychosis mimicking primary psychiatric disorders. The authors reviewed EEG, brain-imaging, and clinical data of 240 patients presenting with acute psychotic episode to assess the diagnostic value of EEG in differentiating ictal psychosis from primary psychosis. Seven patients had interictal spikes, but there were no patients with ictal discharges. There were no significant associations between the tested variables except that taking neuroleptics/antidepressants was associated with abnormal EEG, and older age and taking anti-epileptic drugs were associated with abnormal CT scans. These findings do not support routine use of EEG in patients presenting with acute psychosis.

Non-convulsive status epilepticus: mimics and chameleons

“…EEG has a low yield among unselected patients with psychosis 74. Psychiatric presentations of patients with epilepsy can be difficult to distinguish from NCSE.…”

Mood and behavior disorder in pediatric epilepsy

“…The phenomenology of the psychotic state in seizure is often pleomorphic, with abnormal mood, illusions, delusions (paranoid, disorganized, somatic) and hallucinations (auditory, olfactory, gustatory, somatic and visual), with some clouding of consciousness or no evidence of impaired consciousness [7,88]. Seizures may also present as non-convulsive subtle alteration behavioral disturbances in children [89]. In spite of a relatively clear distinction of these phenomena in psychiatry, Elliot et al [90,91] argue that neurologically, the physiological bases of these phenomena overlap and not supported by similarly discrete electrophysiological signatures.…”

“…Classification of psychosis in epilepsy has been based on duration of psychosis, psychopathology, and presence or absence of seizures, or based on temporal relationship between the two components and can be categorized as [89] Ictal psychosis is, believed to reflect a dysfunction within the temporal lobe and occur in nearly 20% of adults with refractory TLE. PIP is a very specific syndrome in relation to seizure activity and has a clear temporal relationship between the psychotic state of sudden onset and a precipitating bout of complex partial or generalized seizures [89,93]. The lucid interval could last from 2 to 120 h. The recent report of PIP in a 3-year-old puzzles clinicians about the previous under diagnosis or lack of its recognition in pediatric population [99].…”

“…The lucid interval could last from 2 to 120 h. The recent report of PIP in a 3-year-old puzzles clinicians about the previous under diagnosis or lack of its recognition in pediatric population [99]. IIP posits the greatest challenge to distinguish from schizophrenia because of its shared clinical similarities and puzzling onset with no temporal relationship with a seizure episode [89]. In general, the most important differentiating feature is the occurrence of psychotic phenomena following a seizure or series of seizures and its resolution following the event, at which point the patient returns to his or her normal baseline [66].…”

“…In the absence of a formal diagnostic test, a thorough history with collateral information and detailed clinical and mental state examination are the crucial tools for the diagnosis of psychosis in pediatric epilepsy [89]. The treatment of periictal or acute mental disorders is based on epileptic seizure control, while the treatment of interictal or chronic disorders shares more in common with management of disorders, which are purely psychiatric in origin [101].…”