Pelvic Thrusting in a Case of Psychogenic Seizure.

Dear Editor-in-Chief

Psychogenic non-epileptic seizure (PNES), also known as pseudoseizure, pseudo-epileptic seizure and psychogenic seizure, is a psychologically based disorder accompanied with abnormal movements, sensations, emotions and/or behaviors that mimic epileptic seizures, but does not originate from a neurological disturbance (1–3).

Psychogenic seizure, historically known as hysterical seizure (3, 4), is not as scant as it seems to be when we consider the incidence rate of 1.4–3 per 100000 (1, 5), and prevalence rate of 2–33 per 100000 in various studies (2). Another notable point is a considerable female preponderance with up to four-fold more occurrences in some studies (2, 4, 5).

Psychogenic non-epileptic seizure as an important differential diagnosis of intractable seizure accounts for 10–40% of patients referred to epilepsy centers (1, 2, 5). Accordingly, it has posed a real challenge to physicians in order to differentiate between epileptic and non-epileptic patients (2, 5). These patients, who more commonly mimic tonic-clonic and complex partial seizures (1), present with symptoms such as: hypermotor movements, trembling, pelvic thrusting, and falling (5).

We visited a 17-year-old boy with typical pelvic thrusting movement during his seizure-like attacks. He had experienced these attacks for 2 years. His magnetic resonance imaging (MRI) and interictal electroencephalogram (EEG) were completely normal. After psychiatric consultation, diagnosis of psychogenic seizure was confirmed. By treating his psychological problems, the patient was symptom-free during his 6-month follow-up.

Although pelvic thrusting is not a specific symptom, it is one of the strong indicators of psychogenic seizure which could help the physicians in this diagnostic challenge (5).

Inpatient video-electroencephalogram (Video-EEG) monitoring is considered as gold standard for diagnosis of psychogenic non-epileptic seizures (2, 4, 5).