Faculty Bibliography

Autoimmune encephalitis (AE), defined by clinical criteria and its frequent association with neural autoantibodies, often manifests with seizures, which usually stop with immunotherapy. However, a subset of encephalitic conditions present with recurrent seizures that are resistant to immunotherapy. Three primary neurological constellations that fall within this subset are discussed in this Perspective: temporal lobe epilepsy with antibodies against glutamic acid decarboxylase, epilepsy in the context of high-risk paraneoplastic antibodies, and epilepsy following adequately treated surface antibody-mediated AE. These entities all share a common mechanism of structural injury and potentially epileptogenic focal neural loss, often induced by cytotoxic T cells. Recently, we have proposed conceptualizing these conditions under the term autoimmune encephalitis-associated epilepsy (AEAE). Here, we discuss the new concept of AEAE as an emerging field of study. We consider the clinical characteristics of patients who should be investigated for AEAE and highlight the need for judicious use of traditional epilepsy therapeutics alongside immunotherapeutic considerations that are of uncertain and incomplete efficacy for this group of disorders. Last, we discuss future efforts needed to diagnose individuals before structural epileptogenesis has superseded inflammation and to develop improved therapeutics that target the specific immunological or functional disturbances in this entity.

OBJECTIVE/UNASSIGNED:The authors aimed to characterize the long-term psychiatric outcomes and their predictors among survivors of autoimmune encephalitis (AE). METHODS/UNASSIGNED:In this retrospective cohort study, patients diagnosed as having AE between 2008 and 2023 at two academic medical centers (in New York City and Toronto) completed the Mini International Neuropsychiatric Interview 7.0.2 (MINI) and Profile of Mood States (POMS-2) to assess long-term psychiatric outcomes. Clinical characteristics were assessed for potential predictors of psychiatric outcomes. Bivariate analyses and univariate logistic regressions were conducted to assess the relationship between the predictors and the primary outcome. RESULTS/UNASSIGNED:-methyl-d-aspartate (33%), anti-leucine-rich-glioma-inactivated 1 (24%), anti-glutamic acid decarboxylase 65 (14%), and antibody-negative encephalitis (29%). In total, 71% of participants who completed the MINI met criteria for a DSM-5 diagnosis, and 56% were diagnosed as having a mood disorder. Thirteen participants (31%) reported above-average total mood disturbance on the POMS-2. Mann-Whitney U tests revealed that participants diagnosed as having a mood disorder self-reported significantly higher levels of confusion and bewilderment (z=-2.04, p=0.04) and depression and dejection (z=-2.24, p=0.03) and lower levels of vigor and activity (z=-2.62, p=0.01). CONCLUSIONS/UNASSIGNED:AE survivors have a high prevalence of psychiatric comorbid conditions, with most being diagnosed as having a mood disorder and a significant proportion endorsing ongoing mood disturbance. Patients with a psychiatric history may benefit from closer psychiatric follow-up.

INTRODUCTION/UNASSIGNED:Seizures are common in autoimmune encephalitis (AE), but identifying patients at risk of chronic epilepsy in the post-acute phase remains challenging. This study aims to identify risk factors of treatment-resistant postencephalitic epilepsy. METHODS/UNASSIGNED:This retrospective cohort study included patients with AE who experienced new-onset seizures within one year of symptom onset from two tertiary care centers in New York. EEG findings were analyzed separately based on whether the EEG recording was obtained in the acute (<3 months from symptom onset) or subacute phase. A multivariate logistic regression model was used to identify independent predictors of postencephalitic epilepsy. RESULTS/UNASSIGNED:Eighty-nine patients were included (median age: 33 years). Neural antibodies were present in 73% of patients (NMDAR: 35, LGI1: 19, GAD65: 9, Hu: 1, AGNA-1: 1). Over a median follow-up of 4.9 years, 29.2% developed treatment-resistant postencephalitic epilepsy. Independent predictors of postencephalitic epilepsy included focal slowing on acute EEG (OR 0.15, CI 0.02-0.90), interictal epileptiform discharges (IEDs) or periodic discharges (PDs) on subacute EEG (OR 20.01, CI 1.94-206.44), and cell surface antibodies (OR 0.21, CI 0.05-0.89). Immunotherapy within three months of onset was associated with decreased epilepsy development in patients with neural antibodies (OR 4.16, CI 1.11-16.30). CONCLUSIONS/UNASSIGNED:Nearly one-third of patients with AE and acute seizures developed treatment-resistant postencephalitic epilepsy, with significant predictors including absence of focal slowing on acute EEG, presence of IEDs and PDs on subacute EEG, absence of cell surface antibodies, and absence of early immunotherapy treatment of patients with positive neural antibodies.

RGS8-associated paraneoplastic neurologic syndrome (PNS) is a recently-described disorder associated with lymphomas and typically presenting with severe, rapidly-progressing cerebellar dysfunction. We describe a patient who presented with mild signs of cerebellar dysfunction, including ocular motor abnormalities and impaired tandem gait. CSF showed elevated protein and a neural-restricted antibody pattern. Mesenteric lymphadenopathy on abdominal CT was biopsied and diagnosed as follicular B-cell lymphoma. After four years, the previously-detected antibody pattern was identified as RGS8 antibodies. This case describes the first RGS8-PNS patient presenting with a subtle and ocular motor predominant cerebellar syndrome with low-grade lymphoma.

The mechanisms behind comorbid symptoms of depression in persons with epilepsy (PWE) remain largely unknown. Our study aimed to learn whether seizures moderate fluctuations in depressive symptoms in PWE when controlling for preictal symptoms of depression. We enrolled 57 adult PWE admitted to the New York University (NYU) Langone Epilepsy Monitoring Unit (EMU) from 2021 to 2024. Thirty-seven participants had a seizure. Twenty of the admitted patients did not have seizures during the admission period and therefore served as controls. All participants were seizure free for > 7 days prior to participation. Upon admission, all participants completed the Montgomery-Asberg Depression Rating Scale (MADRS) to evaluate baseline mood. The MADRS was repeated acutely (4-24 h post seizure or admission) and subacutely (2-7 days post seizure or discharge) for both groups. Linear regression models revealed that individuals with higher baseline MADRS scores (indicating higher depressive symptoms) experienced worse mood acutely post-seizure, while lower baseline MADRS scores were associated with acute mood improvement (R² = 0.59, p < 0.001). Experiencing a seizure was not associated with subacute mood outcomes, which were instead driven by acute mood state (R² = 0.56, p < 0.001). In conclusion, we found that seizures exacerbate pre-ictal depressive symptoms and that post-ictal depressive symptoms persist up to 7 days after seizure resolution. This study may provide evidence for a bidirectional relationship and demonstrate a vicious cycle between depression and epilepsy.

We propose and prioritize important outcome domains that should be considered for future research investigating long-term outcomes (LTO) after new onset refractory status epilepticus (NORSE). The study was led by the international NORSE Institute LTO Working Group. First, literature describing the LTO of NORSE survivors was identified using a PubMed search and summarized to identify knowledge gaps. Subsequently, a consensus-building process was performed to prioritize and rank important LTO domains for further research. The prioritization of LTO domains was qualitative, enabling the expert panel to generate ideas, share opinions, and provide reasons for the rankings. A second round took place to allow expansion and agreement regarding specific details for each domain. Outcomes were classified into eight main domains: (1) Function: Neuropsychological, Neurological (other than seizures), and Psychiatric (mood and behavior); (2) Quality of Life; (3) Epilepsy; (4) Nonneurological (medical); (5) Social; (6) Caregiver Burden; (7) Long-Term Mortality; and (8) Health Care System Impact. In addition, the working group suggested obtaining outcome measures for each domain at 6 months and 1 year after discharge and annually thereafter until stability has been reached. There are no currently established time frames set for when LTO in NORSE begin or plateau, and previously there existed no consensus regarding which LTO should be considered. This consensus process identifies and recommends NORSE LTO domains that should be considered in future research studies to provide more consistent results that can be compared between studies. Survivors of NORSE should be evaluated serially and at fixed points over time to maximize our understanding of the recovery trajectory for all LTO domains. Establishing reliable and standardized data describing LTO (beyond seizures) after NORSE will support discussions with families during the acute stages, prognostication, the development of targeted management strategies for survivors, and future comparative research globally helping to identify biomarkers that may predict LTO.

BACKGROUND:Isolated psychiatric symptoms can be the initial symptom of pediatric anti-N-methyl-d-aspartate (NMDA) receptor autoimmune encephalitis (pNMDARE). Here we report on the prevalence of isolated psychiatric symptoms in pNMDARE. We also assess whether initial neurodiagnostic tests (brain magnetic resonance imaging [MRI], electroencephalography [EEG], and/or cerebrospinal fluid [CSF] white blood cell count) are abnormal in children with isolated psychiatric symptoms and pNMDARE. METHODS:This multicenter retrospective cohort study from CONNECT (Conquering Neuroinflammation and Epilepsies Consortium) from 14 institutions included children under age 18 years who were diagnosed with pNMDARE. Descriptive statistics using means, medians, and comparisons for continuous versus discrete data was performed. RESULTS:Of 249 children included, 12 (5%) had only psychiatric symptoms without other typical clinical features of autoimmune encephalitis at presentation. All but one (11 of 12 = 92%) had at least one abnormal finding on initial ancillary testing: eight of 12 (67%) had an abnormal EEG, six of 12 (50%) had an abnormal MRI, and five of 12 (42%) demonstrated CSF pleocytosis. The single patient with a normal MRI, EEG, and CSF profile had low positive CSF NMDA antibody (titer of 1:1), and symptoms improved without immunotherapy. CONCLUSIONS:Isolated first-episode psychiatric symptoms in pNMDARE are uncommon, and the majority of children will exhibit additional neurodiagnostic abnormalities. Delaying immunotherapy in a child with isolated psychiatric symptoms and normal neurodiagnostic testing may be warranted while awaiting confirmatory antibody testing.

BACKGROUND AND OBJECTIVES/OBJECTIVE:R). We hypothesized that after a seizure-free period of 3 months, patients with AIE have a seizure recurrence risk of <20% during the subsequent 12 months. This would render them eligible for noncommercial driving according to driving regulations in several countries. METHODS:R-AIE, who had been seizure-free for ≥3 months. We used Kaplan-Meier (KM) estimates for the seizure recurrence risk at 12 months for each antibody group and tested for the effects of potential covariates with regression models. RESULTS:R. DISCUSSION/CONCLUSIONS:Taking a <20% recurrence risk within 12 months as sufficient, patients with NMDAR-AIE and LGI1-AIE could be considered eligible for noncommercial driving after having been seizure-free for 3 months.

PURPOSE/OBJECTIVE:Rasmussen syndrome (RS) is marked by progressive unihemispheric atrophy, resulting in hemiparesis, refractory epilepsy, and cognitive/language decline. Detailed diagnostic and treatment algorithms are currently lacking. We aimed to survey medical providers on their current practices in the diagnosis and treatment of RS. METHODS:A steering committee was formed to create the survey, which was disseminated to the international medical community. One hundred twelve surveys were completed. Descriptive statistics, as well as comparisons by level of experience, patient age group cared for, and geographic region using Fisher's exact test, were conducted. RESULTS:Analysis of cerebrospinal fluid (82 %) and serum (78 %) for autoimmune encephalitis (AE) are completed by most, while approximately one-third obtain genetic and metabolic studies in all patients (36 % and 38 %, respectively). Providers in US and Europe more readily pursue serum AE antibody panels (85 % and 85 %, respectively, versus 67 %, p = 0.019) and genetic testing (56 % and 47 %, respectively, versus 14 %, p < 0.001) than the rest of the world. Thirty-six percent proceed to biopsy in patients otherwise meeting diagnostic criteria, and US providers are more likely to suggest this than others (73 % versus 14-41 %, p < 0.001). Opinions differed on the prioritization of hemispherectomy/hemispherotomy versus immunotherapy in 14 clinical scenarios with various neurologic deficit severity provided. Preferred immunotherapy regimens also varied, with US providers more often choosing IVIG as first-line (67 %) compared to others (28 %-32 %, p = 0.030). Surgical standard of care was identified as functional hemispherectomy or hemispherotomy by 90 %. CONCLUSION/CONCLUSIONS:The survey highlights trends but also significant variations in clinical practice that can serve as targets for future research and expert consensus guidelines.