Case ReportsNonparaneoplastic Anti-GAD Limbic Encephalitis: Seizure Outcome and Long-term Neuropsychological Follow-up After ImmunotherapySpilioti, Martha MD, PhD*; Kiryttopoulos, Andreas MD*; Panou, Theodora PhD†; Simos, Panagiotis PhD†; Alexopoulos, Haris MD, PhD‡; Karafyles, Georgios MD§; Geroukis, Triantafillos MD∥; Kalevrosoglou, Ioannis MD, PhD¶; Kimiskidis, Vasilios MD, PhD* Author Information *First Department of Neurology ¶First Department of Internal Medicine, Aristotle University of Thessaloniki, AHEPA Hospital, Thessaloniki, Greece †Department of Psychiatry & Laboratory of Neuropsychology, University of Crete, Medical School, Heraklion, Greece ‡Department of Pathophysiology, Neuroimmunology Unit, Faculty of Medicine, National and Kapodistrian University of Athens, Athens, Greece §Department of Neurology, “Papageorgiou” Hospital, Thessaloniki, Greece ∥Radiology Department, “G. Papanikolaou” Hospital, Thessaloniki, Greece The authors declare no conflicts of interest. Correspondence: Martha Spilioti, MD, PhD, Aristotle University of Thessaloniki, AHEPA Hospital, First Department of Neurology, Kiriakidi 1, Thessaloniki 546 21, Greece (email: [email protected]). Cognitive and Behavioral Neurology: September 2022 - Volume 35 - Issue 3 - p 212-220 doi: 10.1097/WNN.0000000000000313 Buy Metrics Abstract Antibodies against glutamate decarboxylase (GAD-Abs), especially GAD65 antibodies, are associated with limbic encephalitis (LE) manifested by temporal lobe epilepsy and neuropsychological deficits. We present the case of a 42-year-old Greek woman with nonparaneoplastic anti-GAD LE, discussing the therapeutic management and highlighting the role of neuropsychological assessment. The patient underwent functional and structural brain studies and was investigated longitudinally over a 6-year period with a battery of neuropsychological tests that were designed to document her intellectual function and verbal and visual memory. The patient suffered from refractory temporal-impaired awareness seizures and memory impairment that was mediated by autoimmune nonparaneoplastic LE and comorbid autoimmune disorders (ie, Hashimoto thyroiditis and vitiligo). Neuroimaging studies demonstrated hyperintensities in the medial temporal lobes bilaterally on T2WI MRI sequences. Serial EEGs showed bitemporal intermittent delta activity as well as epileptiform discharges. Tumor blood markers and onconeural antibodies were negative. Immunological screening revealed extremely high GAD-Abs titers in both serum and CSF, as well as the presence of CSF oligoclonal bands. Neuropsychological testing revealed anterograde amnesia with relative preservation of more remote, premorbid memories. The patient underwent first-line immunotherapy followed by immunosuppressive maintenance treatment that led to a reduction of seizures, EEG improvement, and a significant decline in GAD-Abs titers. Neuropsychological evaluations at 5 months, 1 year, and 6 years posttreatment demonstrated improvement, particularly in recent memory and everyday functionality. In this case of anti-GAD LE, the long-term seizure reduction and the improvement of neuropsychological deficits were most likely related to the immunotherapy. Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.