Table 1 Summary of “yellow” clinical characteristics (yellow flag checklist) of PNES patients
From: Clinical differentiation of psychogenic non-epileptic seizure: a practical diagnostic approach
Characteristics | Remarks |
|---|---|
Initial evaluation (ictal and interictal period) in the emergency room (ER) or outpatient settings | |
Female | |
Age 25–35 years old ≥ 60 years old | 44% with PNES only; 15% had both ES and PNES [11] |
Seizure characterized by one or more of the followings: ▪ Gradual onset ▪ Ictal duration > 2 min ▪ Refractory to multiple AEDs ▪ Inconsistent semiology ▪ Does not occur during sleep ▪ Immediately provoked by identifiable emotionally stressful events (domestic violence, public speaking or in front of audience, queueing for a medical procedure) ▪ Afterward memory recollection of the event, despite having a generalized onset seizure | 10–40% of refractory seizures refererred to tertiary epilepsy centers [4, 6] Emotional stress: 74.6%; physical abuse: 17.5%; sexual abuse: 7.9% [8] |
Seizure semiology characterized by one or more of the followings: ▪ Preceded by sensory prodromes (olfactory hallucination, micropsia, and other bizzare sensory experiences) ▪ Unsual motor phenomena: ➢ Out-of-phase limb movement ➢ Side-to-side head movement ➢ Forward pelvic thrusting ➢ Directed rage ▪ Atypical vocalization: ➢ Does not occur ictally ➢ Non-laryngeal origin ➢ Comprehensible word ➢ Memory recall of vocalization ▪ Eye closure characteristics: ➢ Eye closure during the episode ➢ Closed eyes forcefully, resisted passive opening ➢ Inhibited response of oculocephalic reflex as a hallmark ocular sign of PNES | Occurred among 39–56% of PNES patients [7, 9, 12] 56% of motor phenomena [10] 36% of motor phenomena [10] 50% of motor phenomena 20% of PNES patients 17–26% had non-verbal vocalization [8, 9, 13] 63% (vs. 4% of ES) [10] 8.5% [13] > 56% of PNES patients |
Post seizure motor manifestations comprising one or more of the followings: ▪ Retention of some movements (avoidance of falling arm, resistance to passive eye movements, occasional eye blink, positive Henry and Woodruff sign, convergent gaze and eye fixation upon mirror test) ▪ Absence of tongue-biting, urinary and/or fecal incontinence, fall-related trauma, or accidental burn after an episode ▪ Normal corneal reflexes after an episode ▪ Absence of bilateral extensor plantar reflexes ▪ Rapid, shallow, quiet, irregular breathing pattern (resembling an exercise) ▪ Increased sympathetic activity before seizure and parasympathetic activity after seizure ▪ Weeping after event | Occured among 41% of PNES patients |
Laboratory parameters: ▪ Absence of metabolic acidosis on blood gas analysis ▪ Serum prolactin levels ≥ 500 IU/mL | Found in 28.8% of PNES patients and 84.4% of GTCS or partial seizure [14] |
Inpatient setting | |
Association with psychiatric disorders Tend to have cluster A or B personality disorder (primarily boderline personality disorder) • Factitious disorder associated with litigation • Previous history of sexual and physical abuse (including domestic violence) | Cluster A 4 to 31.5%; cluster B 21 to 33% [15] |