Abstracts

Psychogenic nonepileptic seizures (PNES) are found in 20-30% of patients seen at epilepsy centers for intractable seizures. The diagnosis of PNES requires EEG-video monitoring, but for this to happen, clinicians must first [italic]suspect[/italic] PNES in the clinic. We analyzed two independent [quot]red flags[quot] that we felt might predict an eventual diagnosis of PNES: 1) an antecedent diagnosis of [quot]fibromyalgia[quot] or [quot]chronic pain;[quot] and 2) the occurrence of a seizure in the clinic. We reviewed the records of all patients evaluated in a single epilepsy clinic for refractory seizures over 5 years, who eventually underwent EEG-video monitoring. We collected two groups:
1) Group 1: Patients who carried a diagnosis of [quot]fibromyalgia[quot] or [quot]chronic pain.[quot] These diagnoses had to be stated as such and patients had to be under the care of a pain specialist.
2) Group 2: Patients who had an episode during their visit, either the waiting area or the examining room.
We then looked at their final diagnosis following prolonged EEG-video monitoring. Group 1: We identified 28 patients with a diagnosis of [quot]fibromyalgia[quot] and 8 patients with a diagnosis of [quot]chronic pain,[quot] for a total of 36 patients. After EEG-video monitoring, 27 ended up with a diagnosis of PNES. Five were found to have epilepsy, 2 other organic spells, and 2 received no diagnosis. Thus the positive predictive value of a diagnosis of [quot]fibromyalgia[quot] or [quot]chronic pain[quot] was 27/36 = 75%.
Group 2: We identified 13 patients who had a [quot]seizure[quot] during their clinic visit. After EEG-video monitoring, 10 ended up with a diagnosis of PNES, and 3 with a diagnosis of epilepsy, for a positive predictive value of 10/13 = 77%. Both red flags, a history of [quot]fibromyalgia[quot] or [quot]chronic pain[quot] and the occurrence of an episode during the visit, have a high predictive value for an eventual diagnosis of PNES.