Psych

Psychogenic Nonepileptic Seizure

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Psychogenic Nonepileptic Seizure, Psychogenic Seizure, Hysterical Seizure, Pseudoseizure, PNES

  • Epidemiology
  1. Incidence: 1-3 per 100,000
  2. Prevalence: Up to 33 per 100,000
  3. May account for up to 25% of Seizures at Epilepsy centers (ambulatory and inpatient)
  4. Epilepsy patients may also have Psychogenic Seizures in up to 30% of cases
  5. Females account for at two thirds of Psychogenic Seizure patients
  • Precautions
  1. Pseudoseizures (or Psychogenic Seizures) are not Malingering
  2. Patients having Psychogenic Seizures typically do not know this is happening
  • Signs
  1. Atypical Seizure motor activity
    1. Asymmetric arm and leg movement
      1. Often non-focal involving opposite arm and leg (e.g. left arm and right leg activity)
      2. Contrast with Seizures which tend to be focal
    2. Pelvic thrusting
    3. Head turning from side to side
    4. Dystonic Posture
    5. Eyes closed and resists Eyelid movement
    6. Tongue biting limited to tip of Tongue
    7. Avoidance during Seizure
  2. Atypical Seizure timing
    1. Gradual onset and last 2-3 minutes (contrast with 1 minute for typical Seizure)
    2. Waxing and waing course (contrast with rhythmic periodicity of Seizure)
    3. Recur frequently
    4. Typically lacks the postictal period of Seizure disorder
  3. Other factors
    1. Resistance to multiple antiepileptic agents
    2. Emotional or situational triggers
    3. Postictal crying
    4. May remember episode (contrast with Seizure where there is no memory of the episode)
  • Differential Diagnosis
  1. See Nonepileptic Seizure
  2. Atypical epileptic Seizures
    1. Frontal LobeSeizure
      1. Atypical motor and verbal activity
      2. Often occur during sleep and brief duration
    2. Gelastic Seizure (laughs during Seizure)
    3. Myoclonic Seizure
  1. Prolonged Seizure
    1. Oxygen Saturation falls
    2. End-Tidal CO2 rises
  2. Prolonged Psychogenic Seizure
    1. Oxygen Saturation remains normal
    2. End-Tidal CO2 remains normal
  • Diagnosis
  • Inpatient Video EEG
  1. Typical Seizure as confirmed by witnesses of Seizure
  2. No corresponding EEG abnormalities
  3. Interrater reliability of EEG monitoring is poor
    1. Benbadis (2009) Neurology 73(11):843-6 [PubMed]
  • Diagnosis
  • Clinical findings that do not identify Seizure disorder
  1. Postictal Serum Prolactin
  2. Tongue-biting, self-injury or Incontinence
  3. Psychological Testing
  4. Outpatient Electroencephalogram
  • References
  1. Bright, Shoenberger, Stellpflug in Majoewsky (2013) EM:Rap 13(3):3-4