1190 Periodic Limb Movement Disorder Masked by Concurrent Focal Aware Seizures

Introduction Sleep disorders such as sleep apnea and sleep-related movement disorders are more common in patients with epilepsy compared to the general population. Complex rhythmic motor events related to periodic limb movement disorder (PLMD) can overlap with the hypermotor phenomenon of nocturnal seizures, making it a challenging diagnosis solely based on clinical description. The recognition of these repetitive stereotypical movements from seizures would be essential to guide targeted therapy. Report of case(s) We report a patient with focal aware seizures who concurrently experienced sensory symptoms typical of restless leg syndrome (RLS) as her ictal symptoms, as well as paroxysmal nocturnal motor symptoms meeting the diagnostic criteria of PLMD. A 51-year-old right-handed female presented with two years of seizures and nocturnal episodes primarily characterized by creepy crawly feeling in both her upper and lower extremities as well as her trunk with intact awareness. The patient also endorsed non-restorative sleep and daytime sleepiness. During an admission to the epilepsy monitoring unit, several habitual events were recorded that were consistent with fronto-temporal seizures. Interestingly, the majority of her ictal events started with the same creepy crawly sensation. Blood count, serum chemistry, and liver and renal function tests were unremarkable, except for very low serum ferritin levels (4.5 ng/ml) which, in combination with her sensory symptoms raised suspicion for PLMD. Subsequent polysomnography (PSG) showed mild OSA (AHI 9.8/h) and moderate to severe PLMD (43 events/h). Symptoms improved after iron supplementation along with better seizure control (adding lamotrigine to her levetiracetam). A repeat ferritin improved to normal range (46 ng/ml). Conclusion Our case demonstrates that clinical presentation of RLS/PMLD can be indistinguishable from the primary seizure semiology. RLS/PLMD can be a consideration in patients with epilepsy complaining of sensory ictal semiology as seen in this case and may warrant further work-up. Support (if any)