Characteristics and outcome‐related factors of seizure at the first onset of autoimmune encephalitis: A retrospective study

Abstract

Aims Seizure outcome of autoimmune encephalitis (AE) varies from seizure‐free to refractory epilepsy, and the associated factors remain unclear. We aimed to describe seizure characteristics, identify seizure outcome‐related factors, and discuss the medication strategy of antiepileptic drugs (AEDs) at the first onset of AE. Methods We retrospectively studied the data of 86 patients with clinically diagnosed AE. The clinical characteristics were described using a chi‐square test. Seizure outcome‐related factors were assessed using multivariable logistic regression analysis. Results 56 patients were finally enrolled, with antibodies to N‐methyl‐D‐aspartate receptor found in 29, to γ‐aminobutyric acid receptor B found in 13, and to leucine‐rich glioma‐inactivated protein 1 found in 14. Status epilepticus occurrence and onset with seizure lead to a poor seizure outcome, while administration of human gamma globulin and a low antibody titer contributed to a good seizure outcome. Conclusions In the acute phase, seizure characteristics may be considered in the utilization of AEDs. For patients with seizure‐free status in the acute phase, clinical manifestation (onset with seizure or not, whether status epilepticus occurs or not), therapy regimen (human gamma globulin administered or not), and antibody titer may be considered when formulating the strategy for withdrawal of AEDs post‐acute phase.

Acute Symptomatic Seizures and Risk of Epilepsy in Autoimmune Encephalitis: A Retrospective Cohort Study

“…reported similar findings that patients with anti-GABABR encephalitis were more likely to experience status epilepticus, and 68% of them even had refractory status epilepticus ( 6 ). A significant difference was observed in terms of seizure type among groups with anti-NMDAR, anti-LGI1 and anti-GABABR encephalitis, which was in line with the results of prior literature ( 4 , 6 ). FBDS is a unique type of seizure and was only observed in patients with anti-LGI1 encephalitis, which was more frequently reported than other seizure types ( 18 , 19 ).…”

“…Lu et al proposed that EEG abnormalities evaluated by the grand total EEG score may be used as a predictor of long-term seizure outcomes associated with autoimmune encephalitis (22). However, previous studies by Hong et al (8) and Zhang et al (4) failed to observe the predictive role of abnormal EEG results in unfavorable seizure outcomes. Differences in the time points of EEG examinations may lead to inconsistent findings among studies.…”

“…This result is similar to the results of Ding et al., who reported that 21.3% of AE patients developed epilepsy ( 7 ). Wang and colleagues reported that 51.78% of AE patients did not achieve seizure-free status after the acute phase ( 4 ). In another recent study from Spain, 57.89% of patients developed epilepsy after AE ( 11 ).…”

“…It has been increasingly acknowledged in recent years that autoimmune encephalitis (AE) refers to a number of inflammatory autoimmune disorders of the brain that are associated with autoantibodies against neurosurface, synaptic or neuronal intracytoplasmic antigens (1)(2)(3). Acute symptomatic seizures are common clinical manifestations in the acute phase of AE, and more than half of AE patients experience seizure onset (4,5). The effect of anti-seizure medications (ASMs) on acute seizure control is limited, and the responses to ASMs are poor in AE patients (6).…”

“…Studies that focused on the clinical features of acute symptomatic seizures and the predictors of epilepsy development in AE patients are limited, and their findings are controversial ( 4 , 7 , 11 ). Thus, we aimed to answer the following questions in this study: How many AE patients experience acute symptomatic seizures in the acute phase?…”