Characteristics of Seizure and Antiepileptic Drug Utilization in Outpatients With Autoimmune Encephalitis

Prognostic factors underlying the development of drug-resistant epilepsy in patients with autoimmune encephalitis: a retrospective cohort study

OBJECTIVE

The aim of our study was to analyze the characteristics of patients with autoimmune encephalitis (AE) to identify prognostic factors associated with the development of drug-resistant epilepsy (DRE).

METHODS

In this retrospective observational cohort study, we enrolled adult patients with AE between January 2016 and December 2022. The patients were categorized into two groups based on the presence or absence of DRE at the last follow-up. The predictors of the development of DRE were investigated using logistic regression analysis.

RESULTS

Among 121 AE patients, 75.2% (n = 91) experienced acute symptomatic seizures, and 29.8% (n = 36) developed DRE at the last follow-up. On multivariate regression analysis, the factors associated with DRE were antibody negativity (OR 3.628, 95% CI 1.092-12.050, p = 0.035), focal seizure (OR 6.431, 95% CI 1.838-22.508, p = 0.004), refractory status epilepticus (OR 8.802, 95% CI 2.445-31.689, p = 0.001), interictal epileptiform discharges on EEG (OR 6.773, 95% CI 2.206-20.790, p = 0.001), and T2/FLAIR hyperintensity in the limbic system (OR 3.286, 95% CI 1.060-10.183, p = 0.039).

CONCLUSIONS

In this study, the risk of developing DRE was mainly observed among AE patients who were negative for antibodies or had focal seizures, refractory status epilepticus, interictal epileptiform discharges on EEG, and T2/FLAIR hyperintensity in the limbic system.

Acute Symptomatic Seizures and Risk of Seizure Recurrence in Patients with Anti-NMDAR, Anti-LGI1, and Anti-GABABR Encephalitis

AIMS

To analyze the clinical characteristics of acute symptomatic seizures and predict the risk factors for seizure recurrence in patients with anti-N-methyl-D-aspartate receptor (NMDAR), anti-leucine-rich glioma-inactivated 1 (LGI1), and anti-gamma-aminobutyric acid B receptor (GABABR) encephalitis.

METHODS

In this retrospective study, we included hospitalized patients who had been diagnosed with anti-NMDAR, anti-LGI1, and anti-GABABR encephalitis between November 2014 and April 2021. Binary logistic regression analysis was performed to identify the potential risk factors for seizure recurrence.

RESULTS

In total, 262 patients with anti-NMDAR, anti-LGI1, and anti-GABABR encephalitis were included, 197 (75.2%) of whom presented with acute symptomatic seizures. During follow-up, 42 patients exhibited seizure recurrence. In anti-NMDAR encephalitis, frontal lobe abnormality on brain magnetic resonance imaging, delayed immunotherapy, early seizures, and focal motor onset were associated with seizure recurrence.

CONCLUSIONS

Acute symptomatic seizure is a common clinical feature observed in patients with anti-NMDAR, anti-LGI1, and anti-GABABR encephalitis, with 50% of patients presenting with seizures as an initial symptom. The prognosis of patients with acute symptomatic seizures can be improved after receiving immunotherapy. Nevertheless, a minority of patients will experience seizure recurrence; therefore, restarting immunotherapy is recommended.

Clinical study of autonomic dysfunction in patients with autoimmune encephalitis

BACKGROUND

Autoimmune encephalitis (AE) is a collective name, covering an emerging spectrum of autoimmune-mediated neurological diseases related to antibodies and synaptic or intracellular proteins. Anti-NMDAR, anti-LGI1, and anti-GABABR are three types of neuronal cell surface antibodies. Autonomic dysfunction represents a frequently occurring clinical manifestation. This observational study purposes to investigate comparisons between two groups with or without autonomic dysfunction and detect the autonomic dysfunction and other indexes in anti-NMDAR, anti-LGI1, and anti-GABABR cohorts.

METHODS

Patients with anti-NMDAR, anti-LGI1 and anti-GABABR encephalitis were recruited from the May 2017 to the April 2022. The following information was recorded: age, age at onset, tumor presence, gender, prodromal symptoms, clinical manifestations, cranial magnetic resonance imaging, cerebrospinal fluid and blood examinations, and immunotherapy.

RESULTS

There were totally 161 patients enrolled in this study. Among these participants, 104 individuals (64.6%) presented autonomic dysfunction and the remaining 57 (35.4%) were free of autonomic dysfunction. Sinus tachycardia was the most common autonomic dysfunction, followed by pollakiuria/uroclepsia, feverscence, central hypoventilation, sinus bradycardia, constipation, uroschesis, hyperhidrosis, hypersalivation, hypotension, and early satiety/emesis. Compared to patients without autonomic dysfunction, those with autonomic dysfunction had a higher incidence of central hypoventilation and ICU admissions. Meanwhile, in both groups with or without autonomic dysfunction, meatal behavior disorder, cognitive impairment, and epileptic seizure were three most common clinical manifestations. There were no significant differences in cranial magnetic resonance imaging (MRI), cerebrospinal fluid (CSF) examination, antibody titers and number of immunotherapy types. Further analysis of AE mediated by distinct neuronal surface antibodies demonstrated that there were 85 anti-NMDAR, 56 anti-LGI1, and 20 anti-GABABR encephalitis patients. The significant differences between these three cohorts appeared in age, tumor presence, fervescence presence and antibody titers.

CONCLUSION

This study demonstrated the comparisons between autonomic dysfunction group and autonomic dysfunction-free group and provided insights into better diagnosis and treatment.

Early Prediction of Epilepsy after Encephalitis in Childhood Based on EEG and Clinical Features

Objective

The present study was designed to establish and evaluate an early prediction model of epilepsy after encephalitis in childhood based on electroencephalogram (ECG) and clinical features.

Methods

255 patients with encephalitis were randomly divided into training and verification sets and were divided into postencephalitic epilepsy (PE) and no postencephalitic epilepsy (no-PE) according to whether epilepsy occurred one year after discharge. Univariate and multivariate logistic regression analyses were used to screen the risk factors for PE. The identified risk factors were used to establish and verify a model.

Results

This study included 255 patients with encephalitis, including 209 in the non-PE group and 46 in the PE group. Univariate and multiple logistic regression analysis showed that hemoglobin (OR = 0.968, 95% CI = 0.951-0.958), epilepsy frequency (OR = 0.968, 95% CI = 0.951-0.958), and ECG slow wave/fast wave frequency (S/F) in the occipital region were independent influencing factors for PE (P < 0.05).The prediction model is based on the above factors: -0.031 × hemoglobin -2.113 × epilepsy frequency + 7.836 × occipital region S/F + 1.595. In the training set and the validation set, the area under the ROC curve (AUC) of the model for the diagnosis of PE was 0.835 and 0.712, respectively.

Conclusion

The peripheral blood hemoglobin, the number of epileptic seizures in the acute stage of encephalitis, and EEG slow wave/fast wave frequencies can be used as predictors of epilepsy after encephalitis.

The Leading Role of Brain and Abdominal Radiological Features in the Work-Up of Anti-NMDAR Encephalitis in Children: An Up-To-Date Review

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis (NMDARe) is the most common cause of nonviral encephalitis, mostly affecting young women and adolescents with a strong female predominance (F/M ratio of around 4:1). NMDARe is characterized by the presence of cerebrospinal fluid (CSF) antibodies against NMDARs, even though its pathophysiological mechanisms have not totally been clarified. The clinical phenotype of NMDARe is composed of both severe neurological and neuropsychiatric symptoms, including generalized seizures with desaturations, behavioral abnormalities, and movement disorders. NMDARe is often a paraneoplastic illness, mainly due to the common presence of concomitant ovarian teratomas in young women. Abdominal ultrasonography (US) is a key imaging technique that should always be performed in suspected patients. The timely use of abdominal US and the peculiar radiological features observed in NMDARe may allow for a quick diagnosis and a good prognosis, with rapid improvement after the resection of the tumor and the correct drug therapy.

Use of anti-seizure medications in different types of autoimmune encephalitis: A narrative review

Seizures are the main manifestation of the acute phase of autoimmune encephalitis (AE). Anti-seizure medications (ASMs) play an important role in controlling seizures in AE patients, but there is currently a lack of consensus regarding the selection, application, and discontinuation of ASMs. This narrative review focuses on the use of ASMs in patients with AE driven by different antibodies. The PubMed, Embase, and MEDLINE databases were searched up until 30 October 2022 using prespecified search terms. We identified 2,580 studies; 23 retrospective studies, 2 prospective studies and 9 case reports were evaluated based on our inclusion criteria. Anti-N-methyl-D-aspartic-acid-receptor (anti-NMDAR) encephalitis is the type of AE that responds best to ASMs, and long-term or combined use of ASMs may be not required in most patients with seizures; these results apply to both adults and children. Sodium channel blockers may be the best option for seizures in anti-leucine-rich-glioma-inactivated-1 (anti-LGI1) encephalitis, but patients with anti-LGI1 encephalitis are prone to side effects when using ASMs. Cell surface antibody-mediated AE patients are more likely to use ASMs for a long period than patients with intracellular antibody-mediated AE. Clinicians can score AE patients' clinical characteristics on a scale to identify those who may require long-or short-term use of ASMs in the early stage. This review provides some recommendations for the rational use of ASMs in encephalitis mediated by different antibodies with the aim of controlling seizures and avoiding overtreatment.

Seizure outcome-related factors in autoimmune encephalitis: A systematic review and meta-analysis

Background

Identifying the predictors for seizure outcome in autoimmune encephalitis (AE) and investigating how to prevent persistent seizures would have major clinical benefits effectively. Thus, we aimed to perform a systematic review and meta-analysis to examine seizure outcome-related factors in AE patients.

Methods

PubMed and EMBASE were systematically searched from inception to 10 June 2022 for studies investigating seizure outcome-related factors in AE. The pooled effect estimates, including standardized mean differences (SMDs) and odds ratios (ORs) with 95% confidence intervals (CIs), were calculated to estimate the effect of each included factor on the seizure outcome.

Results

A total of 10 studies were included in the meta-analysis. Our pooled results of this meta-analysis showed that five factors were found to increase the risk of persistent seizures in AE patients, including onset with seizures (OR = 2.106, 95% CI = 1.262–3.514, p = 0.004), status epilepticus (OR = 3.017, 95% CI = 1.995–4.563, p &lt; 0.001), EEG abnormalities (OR = 1.581, 95% CI = 1.016–2.46, p = 0.042), MRI abnormalities (OR = 1.554, 95% CI = 1.044–2.283, p = 0.03), and longer time from clinical onset to immunotherapy (SMD = 1.887, 95% CI = 0.598–3.156, p = 0.004).

Conclusion

Our meta-analysis indicated that onset with seizures, status epilepticus, EEG abnormalities, MRI abnormalities, and longer time from clinical onset to immunotherapy were risk factors for persistent seizures in AE patients.

The value of immunotherapy in children with initial short-term frequent seizures

This study aimed to discuss clinical characteristics, therapy, and antibody prevalence in epilepsy (APE) score for short-term, frequent epileptic seizures in children who are autoimmune-antibody negative and respond well to immunotherapy. The clinical characteristics, imaging manifestations, electrophysiology, and effective treatment plan of 9 children who met the above criteria were retrospectively analyzed in the Pediatric Neurology Department of Qilu Hospital at Shandong University from June 2019 to December 2021. All 9 patients (6 boys, 3 girls; aged 13 months−11 years and 5 months, median 3.5 years) had acute-onset seizures within 3 months. All had previous normal growth/development with no family history of disease. Seizure types were focal motor seizures (6), generalized tonic-clonic seizures (2), and generalized secondary-to-focal (1); occurred >10 times/day; and lasted <1 min/episode. Formal treatment with ≥2 types of antiseizure medicine (ASM) achieved an unsatisfactory effect. Cranial magnetic resonance imaging showed an abnormal result in 1 case. The APE score was ≥4 in 3 cases and <4 in 6 cases. All patients experienced symptomatic relief with immunotherapy; subsequently, 8 patients were free of recurrence and 1 had significantly reduced seizure frequency. Autoimmune antibody screening is recommended for children who were previously well and have acute-onset epilepsy; high frequency, short-duration seizures; no good response to 2 types of ASM; and other etiologic factors excluded, even with APE score <4. Even with negative autoimmune antibody results, the possibility of autoimmune epilepsy should be considered for urgent initiation of immunotherapy, which can achieve good results.

Pulmonary infection and baseline mRS scores predict poor prognosis in anti-GABABR encephalitis

Purpose

Anti-gamma-aminobutyric-acid type B receptor (anti-GABABR) encephalitis is a rare autoimmune condition caused by the presence of GABABR antibodies in the limbic system. However, its clinical features and prognostic factors are poorly understood. In this study, we aimed to explore factors that affect the response to first-line treatment in patients with anti-GABABR encephalitis.

Methods

Thirty-four patients with an initial diagnosis of anti-GABABR encephalitis were retrospectively enrolled from December 2015 to June 2021. Clinical features and experimental data recorded within 24 h of admission were extracted from the patients’ medical records. The modified Rankin Scale (mRS) was utilized to assess disease severity at admission and functional recovery after immunotherapy. Independent prognostic factors were determined by ordinal logistic regression analysis.

Results

Of the 34 anti-GABABR encephalitis patients, 12 (35%) presented with cancer; all of these patients had lung cancer. According to multivariate regression analysis, the cancer group exhibited a decrease in the peripheral blood absolute lymphocyte count (ALC) (odds ratio [OR]: 0.063, 95% confidence interval [CI]: 0.006-0.639, P=0.019) and hyponatremia (OR: 9.268, 95% CI: 1.054-81.502, 0.045). In addition, the neutrophil/lymphocyte ratio (NLR), monocyte/lymphocyte ratio (MLR) and platelet/lymphocyte ratio (PLR) did not significantly differ according to mRS scores in patients receiving first-line treatment. No patients with mild or moderate mRS scores (0-2) at admission developed symptoms after treatment; in contrast, only 11 patients with a severe mRS scores (≥3, 11/18) experienced symptom alleviation. Ordinal regression analysis indicated that worse prognosis was associated with pulmonary infection (OR=9.885, 95% CI: 1.106-88.323, P=0.040) and baseline mRS scores (OR= 24.047, 95% CI: 3.294-175.739, P=0.002) in the adjusted model.

Conclusion

Our findings demonstrate that pulmonary infection and baseline mRS scores are independent risk factors for poor prognosis in patients with anti-GABABR encephalitis after first-line treatment. ALC and hyponatremia are potential biomarkers for anti-GABABR encephalitis cases accompanied by lung cancer.

Prevalence, risk factors, and prognosis of drug-resistant epilepsy in autoimmune encephalitis

OBJECTIVE

To evaluate the prevalence and biomarkers of drug-resistant epilepsy (DRE) in patients with autoimmune encephalitis (AIE).

METHODS

Sixty-nine patients with AIE were recruited retrospectively and electroencephalographies (EEGs) were reviewed using a standard reporting proforma. Associations between EEG biomarkers and DRE development at 12 months were examined using logistic regression modeling and were utilized to create a DRE risk score.

RESULTS

Sixteen percent of patients with AIE developed DRE at 12-month follow-up. The presence of status epilepticus (SE) (OR 11.50, 95% CI [2.81, 51.86], p-value <0.001), temporal lobe focality (OR 9.90, 95% CI [2.60, 50.71], p-value 0.001) and periodic discharges (OR 19.12, 95% CI [3.79, 191.10], p-value 0.001) on the admission EEG were associated with the development of DRE at 12 months. These variables were utilized to create a clinically applicable risk score for the prediction of DRE development.

CONCLUSIONS

Drug-resistant epilepsy is an infrequent complication of AIE. Electroencephalography changes during the acute illness can predict the risk of DRE at 12 months post-acute AIE.

SIGNIFICANCE

The identified EEG biomarkers provide the basis to generate a clinically applicable prediction tool which could be used to inform treatment, prognosis, and select patients for acute treatment trials.

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

Purpose

To investigate the clinical characteristics of acute symptomatic seizures and the predictors of the development of epilepsy in patients with anti-NMDAR, anti-LGI1, and anti-GABABR encephalitis.

Methods

We retrospectively screened the medical records of 86 hospitalized patients with confirmed autoimmune encephalitis (AE). The clinical characteristics of acute symptomatic seizures were analyzed. The predictors of the development of epilepsy were investigated using logistic regression analysis.

Results

A total of 86 patients with AE were finally included. Eighty-six percent of patients (n = 74) experienced acute symptomatic seizures, and 28.4% of patients developed epilepsy during follow-up. Abnormal EEG findings were more frequent in AE patients with acute symptomatic seizures. A greater number of anti-seizure medications (ASMs), abnormal EEG findings, and delayed immunotherapy were found to be independently associated with the development of epilepsy.

Conclusion

Acute symptomatic seizures are a common manifestation in AE patients. During follow-up, 28.4% of AE patients developed epilepsy. The independent factors that predicted the development of epilepsy after the acute phase included a larger number of ASMs, EEG abnormalities, and delayed immunotherapy. In clinical practice, we should prioritize immunotherapy to control acute seizures as soon as possible. For AE patients with an increased risk of developing epilepsy, early withdrawal of ASM is not recommended.

Risk Factors for Mortality in Anti-NMDAR, Anti-LGI1, and Anti-GABABR Encephalitis

Objective

We aimed to investigate the mortality rate and identify the predictors of death in patients with anti-NMDAR, anti-LGI1, and anti-GABABR encephalitis.

Methods

Patients with anti-NMDAR, anti-LGI1, and anti-GABABR encephalitis were recruited from the Neurology Department of the First Hospital of Jilin University from March 2015 to November 2021. The primary outcome variable was a binary variable of death vs. survival. The potential risk factors for mortality were evaluated. The mortality rates were determined, and the independent predictors of death were identified using multivariable logistic regression analysis.

Results

A total of 100 hospitalized patients with anti-NMDAR, anti-LGI1, or anti-GABABR encephalitis were included in the final analysis. Fifteen patients (15%) died during a median follow-up period of 18 months. The mortality rates were 10% for anti-NMDAR encephalitis, 2.8% for anti-LGI1 encephalitis, and 41.7% for anti-GABABR encephalitis. The multivariable analysis results showed that older age at onset [adjusted odds ratio (OR) = 1.017, 95% confidence interval (CI) = 1.009–1.136; p = 0.023] was independently associated with an increased risk of death. Antibody type was also associated with mortality. Patients with anti-GABABR encephalitis had 13.458-fold greater odds of dying than patients with anti-LGI1 encephalitis (adjusted OR = 13.458, 95% CI = 1.270–142.631; p = 0.031).

Conclusion

The general mortality rate of anti-NMDAR, anti-LGI1, and anti-GABABR encephalitis was 15%. Age at onset and type of autoimmune encephalitis antibody were independent predictors of death in these patients.

Contemporary advances in anti-NMDAR antibody (Ab)-mediated encephalitis

The study of antibody (Ab)-mediated encephalitis has advanced dramatically since the discovery of antibodies directed against the N-methyl-D-aspartate receptor (NMDAR) in association with a unique neuro-psychiatric syndrome, over a decade-and-a-half ago. Anti-NMDAR Ab-mediated encephalitis now represents the most well characterised form of autoimmune encephalitis. The disease most commonly manifests in young women, but all ages and both sexes can be affected. Autoantibodies may arise in the context of two well-recognised disease triggers in a proportion of patients, and ultimately facilitate NMDAR displacement from synapses. Various CSF cytokines, chemokines, and other molecules have been explored as candidate biomarkers but are limited in sensitivity and specificity. The clinical spectrum is diverse, with evolution and a combination of neuro-psychiatric abnormalities at disease nadir common. Anti-NMDAR Ab-mediated encephalitis is immunotherapy responsive, and a near-majority ultimately acquire a broadly favourable clinical outcome. The diagnosis, and more particularly, the management of the disease can still hold considerable challenges. Moreover, well-defined biomarkers remain elusive. The present review will therefore delineate pathogenic and clinical advances to date in anti-NMDAR antibody-mediated encephalitis.

Predictors and prognoses of epilepsy after anti-neuronal antibody-positive autoimmune encephalitis

PURPOSE

This study aimed to investigate the incidence and predictors of epilepsy after anti-neuronal antibody-positive autoimmune encephalitis (AIE). The clinical outcomes of patients with epilepsy after AIE were also explored.

METHODS

A total of 111 AIE patients were retrospectively evaluated. Post-AIE epilepsy (PAEE) was defined as at least one unprovoked seizure occurring six or more months after discharge from hospital.

RESULTS

The incidence of acute symptomatic seizures was 80.2% (89/111) in our AIE patients. Furthermore, of the 89 AIE patients with seizures, 29 (32.6%) presented with seizures as the initial symptom. Overall, 44 out of 111 AIE patients (39.6%) had unprovoked seizures after six months, meeting our definition of PAEE. The independent risk factors for PAEE incidence included an initial presentation with new-onset refractory status epilepticus (NORSE), delayed immunotherapy treatment, the complication of a lung infection during admission, the requirement for mechanical ventilation during hospitalization, parietal lesions observed in magnetic resonance imaging (MRI), and focal slow waves on electroencephalographic (EEG) monitoring.

CONCLUSIONS

Early initiation of immunotherapy and lung infection treatment may reduce the risk of conversion of symptomatic seizures to chronic epilepsy in the acute phase of AIE. In general, PAEE patients could have a good prognosis if treated properly and in a timely fashion.

Association between autoimmune encephalitis and epilepsy: Systematic review and meta-analysis

BACKGROUND

Diverse neuronal antibodies are related to autoimmune encephalitis (AE) and AE-related epilepsy. However, the epidemiological characteristics of AE, AE-associated antibodies, and AE-related seizures are still unclear.

AIMS

This research evaluated the relationship between AE, AE-related seizures, and neuronal antibodies, as well as the morbidity of AE with early incidence.

METHODS

The PubMed, Embase, Cochrane, and Web of Science databases were searched. Pooled estimates and 95% confidence intervals (CIs) were calculated using a random-effects model.

RESULTS

Of the 4,869 citations identified, 100 articles were reviewed in full, and 42 subgroups were analyzed. The overall incidence of AE patients with seizures was 42% (95% CI: 0.40-0.44), and among them, the incidence of epilepsy in anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis patients was 73% (95% CI: 0.70-0.77). Subsequently, we found that the prevalence of AE as the cause of epilepsy within the pooled period was 1% (95% CI: 0.01-0.02), while the overall positive rate of neuronal antibodies in epilepsy patients was 4% (95% CI: 0.03-0.05). Additionally, the detection rates of different antibodies among epilepsy patients were as follows: anti-NMDAR, 1%; anti-leucine-rich glioma inactivated 1 (LGI1), 1%; anti-contactin-associated protein-like 2 (CASPR2), 2%.

CONCLUSION

Based on our findings, neuronal antibodies may serve as a bridge to study AE and immune-related epilepsy. To further understand the differences in outcomes following different treatment measures, and to provide more information for public health policy and prevention, more research is needed to improve the accuracy of estimations.

Meningioma preceding CASPR2 antibody limbic encephalitis with a stroke mimic: A case report

RATIONALE

Todd paralysis (a stroke-like presentation in some patients with epilepsy) caused by limbic encephalitis (LE) is not easily distinguished from acute ischemic stroke by clinicians in the emergency room.

PATIENT CONCERNS

We report a contactin-associated protein-like 2-antibody (CASPR2-Ab)-positive patient who presented with atypical LE.

DIAGNOSES

CASPR2-Ab-positive LE was the presumed diagnosis. Re-evaluation of cerebrospinal fluid (CSF) samples revealed autoantibodies targeting CASPR2 at an immunoglobulin G titer of 1:1. The clinical presentation of subacute onset seizures, abnormal electroencephalography, hypermetabolism on positron emission tomography, good immunotherapy response, and the presence of specific antibodies in serum supports a diagnosis of autoimmune LE.

INTERVENTION

The patient received glucocorticoids (1 g for 3 days and 500 mg for 3 days), immunoglobulin (25 g for 3 days), sodium valproate (1 g for 3 days), and clonazepam (1 mg for 3 days).

OUTCOMES

Remission of temporal lobe epilepsy symptoms and cognitive dysfunction was observed. Follow-up analysis of CSF and serological examination were not approved by the patient. His Mini-Mental State Examination score improved to 21/30. Stable remission of symptoms was achieved throughout the follow-up period of 50 days.

LESSONS

Autoimmune encephalitis (AE) should be considered in cases of late-onset epilepsy following meningioma peritumoral brain edema and resection. A diagnosis of AE should be considered in patients presenting with stroke-like symptoms if the magnetic resonance imaging abnormality does not match a known vascular territory. Early and correct diagnosis is crucial because immunotherapy is usually effective for this disease.

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

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.

Associations between seizures and MRI in patients with anti-NMDAR encephalitis

OBJECTIVES

Seizures are a prominent feature of anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis. Nearly half of brain magnetic resonance image (MRI) results are abnormal. The aim of our study was to evaluate the associations between seizures and brain MRI results in patients with anti-NMDAR encephalitis.

METHODS

Patients with anti-NMDAR encephalitis were enrolled between January 2015 and December 2018. The patients included were divided into normal and abnormal MRI groups. Seizure outcomes and modified Rankin Scale scores at the 1-year follow-up were assessed. Seizure characteristics and outcomes were compared between groups.

RESULTS

Of 35 patients with anti-NMDAR encephalitis, 28 patients (80%) had reported seizures in the acute phase. Patients with abnormal MRI findings more frequently had focal seizures than patients with normal MRI findings (72.7% vs 17.6%, P < .01). The incidence of patients treated with 2 or more antiepileptic drugs was higher in the normal MRI group than in the abnormal MRI group (100% vs 45.4%, P < .01). The onset-immunotherapy time was shorter in the abnormal MRI group than in the normal MRI group (P < .05). There were no statistically significant differences in seizure outcomes between the normal and abnormal MRI groups (P > .05).

CONCLUSIONS

Focal seizures were most common in patients with abnormal MRI lesions. In the acute stage of the disease, the abnormal MRI group was more likely than the normal MRI group to achieve seizure control. Abnormal MRI findings did not affect the overall good prognosis of patients with anti-NMDAR encephalitis with seizures.

Delta brush variant: A novel ictal EEG pattern in anti-NMDAR encephalitis

Seizure is one of the main symptoms of anti-NMDAR encephalitis, but data of ictal electroencephalogram (EEG) patterns remain limited. In this study, we aimed to introduce a unique ictal pattern. This delta brush variant (DBV) was characterized as generalized delta rhythm with fast spike activity riding on it. We retrospectively evaluated the ictal pattern from six patients with anti-NMDAR encephalitis, and patients were grouped based on the presence of DBV. DBV was found in two patients who were in the florid phase of the disease: (a) A 17-year-old girl experienced rhythmical jerking of bilateral limbs. Corresponding EEG patterns showed generalized DBV. Seizure terminated after intravenous injection of midazolam, but oral-facial dyskinesia reappeared; and (b) a 24-year-old man suffered stiffening of the right limbs and oral-facial dyskinesia. The EEG pattern showed frontal DBV with left prominence. Seizure was controlled, but oral-facial dyskinesia remained after intravenous injection of midazolam. Compared with patients without DBV, patients in this group were more likely to have prolonged excessive delta brush (100% vs 25%) and hyperpyrexia (39.7℃ vs 38.2℃). Duration in ICU (36 days vs 18 days) and hospital (52 days vs 36 days) was relatively longer in DBV group, and no significant difference was found in terms of the mRS score (1 vs 0.5) and seizure relapse rate (0% vs 25%) during 3-month follow-up. DBV is a peculiar pattern in anti-NMDAR encephalitis. An EEG-based monitoring should be considered to avoid misleading this ictal EEG pattern to the electromyographic artifact.

Seizures and risk of epilepsy in anti-NMDAR, anti-LGI1, and anti-GABAB R encephalitis

Background

Accumulating data have suggested seizures occur frequently in patients with neuronal surface antibody‐mediated autoimmune encephalitis. We aimed to evaluate seizure outcomes and potential factors associated with the development of epilepsy in patients with anti‐N‐methyl‐D‐aspartate receptor (NMDAR), anti‐leucine‐rich glioma‐inactivated 1 (LGI1), and anti‐gamma‐aminobutyric‐acid B receptor (GABA_BR) encephalitis.

Methods

Patients with anti‐NMDAR, anti‐LGI1, and anti‐GABA_BR encephalitis were prospectively recruited from 2014 to June 2019, with a median follow‐up period of 30.5 months (range 8–67 months). Seizure outcomes were assessed and risk factors of epilepsy were analyzed.

Results

A total of 119 patients with anti‐NMDAR, anti‐LGI1, and anti‐GABA_BR encephalitis were included, and 83 (69.7%) of them developed new‐onset seizures. By the end of follow‐up, 17 (21.3%) of 80 patients had seizure relapses after intermittent seizure remission or exhibited uncontrolled seizure episodes, contributing to epilepsy. Immunotherapy delay and interictal epileptic discharges (IEDs) were identified to be associated with the development of epilepsy in patients with anti‐NMDAR, anti‐LGI1, and anti‐GABA_BR encephalitis, particularly anti‐NMDAR encephalitis. Furthermore, multivariate logistic regression analysis demonstrated that immunotherapy delay was an independent predictor for epilepsy.

Conclusion

Our study suggested that immunotherapy delay and IEDs were associated with the development of epilepsy in patients with anti‐NMDAR, anti‐LGI1, and anti‐GABA_BR encephalitis. Early diagnosis and treatment were required, and particular consideration should be given to patients with these risk factors.

Risk of epilepsy in rheumatoid arthritis: a meta-analysis of population based studies and bioinformatics analysis

Background:

An increasing number of studies support an association between rheumatoid arthritis (RA) and brain disorders. This study aims to determine the association between RA and epilepsy.

Methods:

A comprehensive search of databases in both English and Chinese was performed. Data from the selected studies were extracted and analyzed independently by two authors. Genes associated with epilepsy and RA were also collected and analyzed.

Results:

We included six nationwide population based studies (n = 7,094,113 cases in total) for the meta-analysis. The risk of epilepsy was increased in RA patients [risk ratio (RR) = 1.601; 95% confidence interval (CI): 1.089–2.354; p = 0.017; n = 3,803,535 cases] and children born to mothers with RA (RR = 1.475; 95% CI: 1.333–1.633; p < 0.001, n = 3,290,578 cases). Subgroup analysis and meta-regression showed the RR of epilepsy in RA was negatively correlated with age. Furthermore, we found that 433 identified genes in a coexpression network from the hippocampi of 129 epileptic patients were enriched in the RA and related Kyoto Encyclopedia of Genes and Genomes pathways, while 13 genes (mainly related to inflammatory cytokines and chemokines) were identified as potential key genes bridging the RA and epilepsy.

Conclusions:

Our study, utilizing meta-analysis and bioinformatical data, highlights a close association between epilepsy and RA. Further studies are still warranted to expand these findings, especially for a population that is exposed to RA during fetal and childhood periods.

Clinical characteristics and long-term follow-up of seven cases of anti-GABABR encephalitis in patients of Han Chinese descent

Objective

To improve the diagnosis and treatment of anti-GABAB receptor (anti-GABABR) encephalitis and prevent misdiagnosis or non-diagnosis.

Methods

We retrospectively examined the chief clinical manifestations, auxiliary examination results, treatment strategies, treatment efficacy, and long-term follow-up results of seven consecutive patients with anti-GABABR encephalitis.

Results

Epileptic seizures were the first symptom in 100% of the patients; 85.7% had memory deficit in the hospital, 42.8% had residual symptoms of cognitive impairment at discharge, and 28.6% had cognitive impairment at the end of follow-up; 71.4% of the patients had psychosis in the hospital, 57.1% had residual symptoms of psychosis at discharge, and 14.3% still had psychosis at the end of follow-up. However, the clinical symptoms (psychiatric disorders, cognitive decline) and signs (consciousness disturbance) at onset and after follow-up were not significantly different (P > 0.05). In 71.4% of the patients, anti-GABABR antibody serum levels were higher than those in the cerebrospinal fluid (especially in patients with lung cancer). Magnetic resonance imaging in 71.4% of patients indicated that the marginal lobe demonstrated encephalitis lesions. The average modified Rankin Scale score (2.0 ± 2.31) at follow-up was significantly better than that (3.86 ± 0.90) at the time of admission (P < 0.05).

Conclusion

The clinical characteristics of anti-GABABR encephalitis were refractory epilepsy, psychiatric disorders, and cognitive impairment. Multiple antiepileptic drugs are crucial for the treatment of intractable epilepsy. Clinicians should eliminate the possibility of small-cell lung cancer in patients with high anti-GABABR antibody levels. Early active immunotherapy is effective, and the long-term prognosis is good for patients without tumors.