Abstracts

Rationale: Approximately 4-60 % of patients with psychogenic nonepileptic seizures (PNES) have coexisting epileptic seizures (ES). The diagnosis and management of these patients is a huge burden on resources given the two diagnoses require different therapies. We attempt to compare the ictal semiology, localization and imaging characteristics of patients with ES and those with mixed ES and PNES. Methods: Data from Parkland Memorial Hospital Epilepsy Monitoring Unit (EMU) between 6/1997 and 6/2014 was reviewed. Only patients with EEG proven ES were included. Those with only interictal epileptiform abnormalities were excluded. A subset with comorbid PNES (ES+PNES) was further analyzed in terms of demographics, diagnostic yield of first EMU evaluation, PNES semiology, and impact of psychiatry consultation on EMU readmission rate. In addition, ictal localization and MRI lesional status were compared between the ES+PNES group and ES only group. Potential management pitfalls of the ES+PNES group were evaluated. Fisher's test was used for statistics. Results: Of 4828 unique patients (6559 admissions), 2738(57%) had a diagnostic EMU evaluation, of which 1488(54%) had exclusive ES, 1135(41%) had exclusive PNES, and 112(4%) had ES+PNES. 43 of the exclusive PNES group had interictal epileptiform abnormalities, but were not considered part of the ES+PNES group since no epileptic seizures were captured. The ES+PNES group consisted of 69% females, while the ES group had 51% (p<0.0001). No history of abuse was obtained in 91% of ES+PNES patients who had a psychiatric consultation. However, depression was seen in 32% and bipolar disorder in 3.5%. 55% were diagnosed with ES+PNES during their first EMU evaluation, while only ES or PNES was diagnosed in 25% and 13%, respectively, and 7% had a nondiagnostic evaluation. The MRI was lesional in 63% and 43% of the ES and ES+PNES groups, respectively (p<0.0001) (Figure 1 and Table 1). Focal seizures were seen 87% of the time in both ES and ES+PNES groups. Out of the localizable focal seizures, the temporal lobe was involved 75% (ES) and 79% (ES+PNES) of the time (p=0.27). Semiology of PNES in ES+PNES group was focal without cognitive changes in 21%, dyscognitive in 46%, convulsive in 30%, and multiple semiologies in 5%. Psychiatry was consulted only in 38% of the ES+PNES cases. In those consulted, EMU readmission rate was 37% compared to 45% when no consultation was done (p=0.439). Conclusions: Our data suggests that the patients with coexisting PNES and epilepsy have unique characteristics. Majority of the patients in this group lacked conventional risk factors for PNES, such a history of abuse. Obtaining an in-house psychiatry consult lead to a trend of decreased readmission rates. Failure to characterize all the historical semiologies should be considered as an incomplete evaluation and a repeat evaluation should be encouraged. The key for management for ES+PNES group is a team approach between the neurologist and mental health provider.