Misdiagnosis of epileptic seizures as manifestations of psychiatric illnesses

Can J Neurol Sci. 2011 May;38(3):487-93. doi: 10.1017/s0317167100011914.

Abstract

Background: Epileptic seizures may be misdiagnosed if they manifest as psychiatric symptoms or seizures occur in patients with known psychiatric illness.

Methods: We present clinical profiles of six patients with epilepsy (three male, mean age 39 ± 12 years) that presented with prominent psychiatric symptoms.

Results: Two patients had pre-existing psychiatric illnesses. Three patients were initially diagnosed with panic attacks, two with psychosis, and one with schizophrenia. Five patients had temporal lobe epilepsy (TLE) while the sixth patient was subsequently found to have absence status epilepticus (SE). Cranial computed tomogram (CT) including contrast study was unremarkable in five patients and showed post-traumatic changes in one patient. Cranial magnetic resonance imaging (MRI) revealed dysembryoplastic neuroepithelial tumour (DNET) in one patient, cavernous hemangioma in one, and post-traumatic changes plus bilateral mesial temporal sclerosis in another patient but it was normal in two TLE patients. Routine electroencephalography (EEG) revealed absence SE in one patient but it was non-diagnostic in the TLE patients. Video-EEG telemetry in the epilepsy monitoring unit (EMU) was necessary to establish the diagnosis in four TLE patients. None of the patients responded to medications aimed at treating psychiatric symptoms alone. Two patients required surgery while the other four required treatment with anti-epileptic drugs. All the patients had favorable response to the treatment of their epilepsy.

Conclusions: This case series illustrates that epileptic patients may experience non-convulsive seizures that might be mistaken as primary psychiatric illnesses. In this subset of patients, evaluation by an epileptologist, MRI of the brain, and/or video-EEG telemetry in an EMU was necessary to confirm the diagnosis of epilepsy if routine EEGs and cranial CT are normal.

MeSH terms

  • Adult
  • Diagnostic Errors*
  • Electroencephalography / methods
  • Epilepsy / diagnosis*
  • Female
  • Humans
  • Magnetic Resonance Imaging / methods
  • Male
  • Mental Disorders / physiopathology*
  • Middle Aged
  • Retrospective Studies
  • Tomography, X-Ray Computed / methods
  • Video Recording
  • Young Adult