Brain‐responsive neurostimulation treatment in patients with GAD65 antibody–associated autoimmune mesial temporal lobe epilepsy

Abstract

Glutamic acid decarboxylase 65‐kilodalton isoform (GAD65) antibodies have been associated with multiple nonneurological and neurological syndromes including autoimmune epilepsy (AE). Although immunotherapy remains the cornerstone for the treatment of AE, those with GAD65 Ab‐associated AE (GAD65‐AE) remain refractory to immunotherapy and antiseizure medication (ASM). Outcomes of epilepsy surgery in this patient population have also been unsatisfactory. The role of neuromodulation therapy, particularly direct brain‐responsive neurostimulation therapy, has not been previously examined in GAD65‐AE. Here, we describe four consecutive patients with refractory GAD‐65‐associated temporal lobe epilepsy (GAD65‐TLE) receiving bilateral hippocampal RNS System treatment. The RNS System treatment was well tolerated and effective in this study cohort. Three patients had a >50% clinical seizure reduction, and one patient became clinically seizure‐free following resective surgery informed by the RNS System data with continued RNS System treatment. In all four of our patients, the long‐term ambulatory data provided by the RNS System allowed us to gain objective insights on electrographic seizure lateralization, patterns, and burden as well as guided immunotherapy and ASM optimization. Our results suggest the potential utility of the RNS System in the management of ASM intractable GAD65‐AE.

Autoimmune Encephalitis–Related Seizures and Epilepsy: Diagnostic and Therapeutic Approaches

“…48 However, some patients might be candidates for neuromodulation therapy, including responsive neurostimulation therapy, which has been approved for treating adults with medically refractory focal onset seizures arising from 1 or 2 foci. 49 The primary concern in using chronically implanted devices, including the responsive neurostimulation system, is the risk of device-related infection because some of these patients may be receiving chronic immunosuppressive treatments. Prospective multicenter trials are needed to examine the risks and efficacies of these devices in patients with drug-resistant AAE.…”

Ketogenic Diet Therapy for the Treatment of Post-encephalitic and Autoimmune-Associated Epilepsies

“…More recently, neuromodulation therapy was reported in patients with AE. Feyissa et al ( 49 ) reported four patients with GAD-65 associated epilepsy treated with responsive neurostimulation (RNS) system. Three patients achieved ≥50% seizure reduction and one patient became seizure-free after RNS data-guided temporal lobectomy ( 49 ).…”

“…Feyissa et al ( 49 ) reported four patients with GAD-65 associated epilepsy treated with responsive neurostimulation (RNS) system. Three patients achieved ≥50% seizure reduction and one patient became seizure-free after RNS data-guided temporal lobectomy ( 49 ). In addition to immunotherapy, anti-seizure drugs, and neuromodulation, our case series adds ketogenic diet therapy to the list of potential treatments for epilepsy in patients with PE and AE.…”

Brain-responsive neurostimulation in adult-onset rasmussen's encephalitis

“…The RNS System provides data in a naturalistic setting and may complement inpatient iEEG data and contribute to treatment decisions. Although there have been reports of neuromodulation therapy in autoimmune associated epilepsies [5] , very limited data exists on RE. To the best of our knowledge, there is only one reported case of RE with drug-resistant epilepsy treated with RNS system [6] ; La Vega-Talbott et al reported a similar case, however in a childhood-onset RE, where an 18-year-old male with a childhood-onset RE underwent successful RNS therapy after failure of several ASMs, immunotherapy and other neurostimuators.…”