To study the prevalence of systemic autoimmune diseases in idiopathic epilepsy and seizure control in patients with both Idiopathic Epilepsy and systemic autoimmune diseases.

Idiopathic Epilepsy constitutes about one third of all epilepsies in adults. Its treatment is limited to symptomatic antiseizure medications. Studies showed patients with epilepsy have a more than 2.5 fold increased risk of systemic autoimmune diseases while patients with systemic autoimmune diseases also have more than 2.5 fold increased risk of Epilepsy. How immune modulating therapy affect seizure control is still unknown.

A retrospective study of medical records from patients seen in epilepsy clinic in our center in 2016 to assess the prevalence of systemic autoimmune diseases in adult patients with idiopathic epilepsy. Epilepsy outcome of patients with or without immunosuppressive therapy for systemic autoimmune diseases was assessed. Patients with post-traumatic epilepsy, lesional epilepsy and CNS Autoimmune diseases were excluded.

A total of 103 female patients with average age of 34.1 (±19.2) years old and 40 male patients with average age of 45.4 (±18.5) years old were included in the study. 17.5% female patients and 12.5% male patients with idiopathic epilepsy had co-occurrence of systemic autoimmune diseases. None of those patients on immunosuppressive therapy had medically refractory epilepsy. 30.4% of patients with systemic autoimmune diseases not on immunosuppressive therapy suffered from medically refractory Epilepsy.

The prevalence of systemic autoimmune diseases in idiopathic epilepsy is 1.8 fold higher than in general population. Immunosuppressive therapy can contribute to optimal seizure control.