anti-GABABR Encephalitis Research Articles

Anti-γ-aminobutyric acid-B receptor autoimmune encephalitis with syncope as the initial symptom: Case report and literature review

Abstract Autoimmune encephalitis (AE) associated with autoantibodies against γ-aminobutyric acid-B receptor (GABABR-AE) is frequently identified in middle-aged and elderly males. The disease is characterized by seizures, mental, and behavioral abnormalities, as well as recent memory decline. Anti-GABABR antibody-associated encephalitis, presenting with syncope as the first symptom is rare. Here we report a case of AE with syncope as the first symptom. A 55-year-old male presented to the emergency department with transient loss of consciousness, initially diagnosed as syncope. As the disease progressed, the patient exhibited seizures, abnormal mental behavior, and cognitive impairment. Ultimately, the patient was diagnosed with right lung small cell lung cancer. The initial atypical symptoms and the lack of clear imaging features of GABABR encephalitis hinder early diagnosis. This case highlights the importance of screening for the underlying etiology of syncope in middle-aged and elderly patients.

Anti-GABAB receptor encephalitis: clinical and laboratory characteristics, imaging, treatments and prognosis.

Anti-GABABR encephalitis is a rare disease reported to be often associated with tumors. The current study aims to summarize the clinical characteristics, imaging features, treatments, outcomes and explore the potential prognosis risk factors of patients with anti-GABABR encephalitis. Patients tested positive for anti-GABABR were retrospective studied from a single medical center in China over a period of 3 years. They were followed up for a maximum period of 18 months. Clinical data were summarized and prognostic factors including demographic characteristics, laboratory tests, and neurological functions were compared between survived and deceased patients at 18 months follow-up. Twenty-six patients, 10 females (38.5%) and 16 males (61.5%), diagnosed with anti-GABABR encephalitis were studied. The median age was 58 years. Of the 23 cases with complete clinical data, their main manifestations were epileptic seizures (65%), mental and behavioral abnormalities (52%), and cognitive impairment (48%). 7 (30.4%) cases had tumors: 5 small cell lung cancer (SCLC), 1 rectum adenocarcinoma (moderately differentiated) and 1 esophageal squamous cell carcinoma. MRI showed 5 (22%) cases had T2 FLAIR increased signals in cortex but with different regions affected. One of the two patients scanned for PET-CT showed hypermetabolism in the left temporal lobe region. The disease course ranged from 5 days to 3 years. 2 patients (one had esophageal carcinoma) without immunotherapy and 3 patients (one had SCLC) that did not response to immunotherapy died soon after diagnosis. 18 patients improved after immunotherapy while 3 (all had SCLC) died after relapses. The prevalence of epileptic seizures and malignancies was significantly lower in the survival group than in the deceased group at 18-months follow-up, the same as the admission mRs score. Serum fibrinogen, cerebrospinal fluid immunoglobulin G quotient, and 24-hour intrathecal synthesis rate were significantly lower in the survival groups as well. Cortex T2 FLAIR abnormalities were only observed in a small proportion of anti-GABABR encephalitis patients with heterogeneous MRI phenotypes. High mRS score at admission, epileptic seizures and the presence of a tumor indicated a poor prognosis, while the underlying mechanism of the later two factors should be investigated further.

Clinical characteristics and outcomes of patients with antibody-related autoimmune encephalitis presenting with disorders of consciousness: A prospective cohort study.

To explore the clinical characteristics, short- and long-term functional outcomes, and risk factors for antibody-related autoimmune encephalitis (AE) in patients with disorders of consciousness (DoC). Clinical data were collected from AE patients admitted to Xuanwu Hospital of Capital Medical University from January 2012 to December 2021, and patients were followed up for up to 24 months after immunotherapy. A total of 312 patients with AE were included: 197 (63.1%) with anti-NMDAR encephalitis, 71 (22.8%) with anti-LGI1 encephalitis, 20 (6.4%) with anti-GABAbR encephalitis, 10 (3.2%) with anti-CASPR2 encephalitis, 10 (3.2%) with anti-GAD65 encephalitis, and 4 (1.3%) with anti-AMPAR2 encephalitis. Among these patients, 32.4% (101/312) presented with DoC, and the median (interquartile range, IQR) time to DoC was 16 (7.5, 32) days. DoC patients had higher rates of various clinical features of AE (p < .05). DoC was associated with elevated lumbar puncture cerebrospinal fluid (CSF) pressure, CSF leukocyte count, and specific antibody titer (p < .05). A high percentage of patients in the DoC group had a poor prognosis at discharge and at 6 months after immunotherapy (p < .001), but no significant difference in prognosis was noted between the DoC group and the non-DoC group at 12 and 24 months after immunotherapy. Dyskinesia (OR = 3.266, 95% CI: 1.550-6.925, p = .002), autonomic dysfunction (OR = 5.871, 95% CI: 2.574-14.096, and p < .001), increased CSF pressure (OR = 1.007, 95% CI: 1.001-1.014, p = .046), and modified Rankin scale (mRS) score ≥3 at the initiation of immunotherapy (OR = 7.457, 95% CI: 3.225-18.839, p < .001) were independent risk factors for DoC in AE patients. DoC is a relatively common clinical symptom in patients with AE, especially critically ill patients. Despite requiring longer hospitalization, DoC mostly improves with treatment of the primary disease and has a good long-term prognosis after aggressive life support and combination immunotherapy.

Diagnostic signatures and immune cell infiltration characteristics in anti-GABABR encephalitis

PurposeAnti-gamma-aminobutyric acid B receptor (GABABR) encephalitis is an uncommon form of autoimmune encephalitis associated with a poor prognosis and a high fatality rate. We aim to find diagnostic markers for anti- GABABR encephalitis as well as the effects of immune cell infiltration on this pathology. MethodsFor quantitative proteomic analysis, isobaric tags for relative and absolute quantitation were used in conjunction with LC-MS/MS analysis. To conduct functional correlation analyses, differentially expressed proteins (DEPs) were identified. Following that, we used bioinformatics analysis to screen for and determine the diagnostic signatures of anti- GABABR encephalitis. ROC curves were used to evaluate the diagnostic values. To assess the inflammatory status of anti- GABABR encephalitis, we used cell-type identification by estimating relative subsets of the RNA transcript (CIBERSORT) and explored the link between diagnostic markers and infiltrating immune cells. ResultsOverall, 108 robust DEPs (47 upregulated and 61 downregulated) were identified, of which 11 were immune related. The most impressively enriched pathways were complemented and coagulation cascades, actin cytoskeleton regulation, and cholesterol metabolism; GSEA revealed that the enriched pathways were considerably differentially connected to immune modulation. Eleven immune-related DEPs were chosen for further investigation. We developed a novel diagnostic model based on CSF1R and AZGP1 serum levels using ROC analysis (area under the ROC curve = 1). M1 macrophages and activated natural killer cells are likely to play a role in course of anti- GABABR encephalitis. ConclusionWe identified CSF1R and AZGP1 are possible anti-GABABR encephalitis diagnostic indicators, and immune cell infiltration may have a significant impact on the development and occurrence of anti- GABABR encephalitis.

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

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. 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. 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. 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

BackgroundAutoimmune 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. MethodsPatients 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. ResultsThere 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. ConclusionThis study demonstrated the comparisons between autonomic dysfunction group and autonomic dysfunction-free group and provided insights into better diagnosis and treatment.

Assessment of disease severity and patient prognosis in anti-GABABR encephalitis with and without comorbid tumors.

This study aimed to analyze the severity of the condition and prognosis of patients with anti-gamma-aminobutyric-acid type B receptor (anti-GABABR) encephalitis with tumors. Patients with anti-GABABR encephalitis admitted to one of two hospitals from 2020 to 2022 were enrolled and divided into tumor and non-tumor groups. The clinical characteristics, condition severity, treatment options, and prognosis of the two groups of patients were compared and analyzed. Eighteen patients with anti-GABABR encephalitis were included, ten of whom had tumors. The comparison of clinical characteristics showed that rates of status epilepticus and coma were significantly higher in the group with tumors (P = 0.013 and P = 0.025, respectively); the incidences of pulmonary infection, respiratory failure, hyponatremia, and hypoproteinemia were also substantially more frequent in the tumor group (P = 0.054, P = 0.036, P = 0.015, and P = 0.025, respectively). The laboratory test result comparison showed that serum neuron-specific enolase (NSE) and carcinoembryonic antigen (CEA) were present only in the group with tumors (P = 0.036 and P = 0.092, respectively), but there was no significant difference in the occurrence of elevated CEA between the two groups. Conversely, the percentage of serum systemic autoimmune antibodies was higher in the group without tumors than in the group with tumors (P = 0.043). Patients with tumors tended to have poor outcomes (P = 0.152, OR: 7.000). Severe brain damage and complications occur in patients with anti-GABABR encephalitis and comorbid tumors. Early screening for serum NSE and CEA helps in the early diagnosis and treatment of tumors. The prognosis is much worse for anti-GABABR encephalitis with tumors.

Elevated cerebrospinal fluid YKL-40 levels in patients with anti-gamma-aminobutyric- acid-B receptor encephalitis

ObjectiveAnti-gamma-aminobutyric-acid-B receptor (GABAbR) encephalitis is a rare form of autoimmune encephalitis. Until now, there are few biomarkers that can indicate the severity and prognosis of patients with anti-GABAbR encephalitis. The objective of this study was to exam the changes of chitinase-3-like protein 1 (YKL-40) in patients with anti-GABAbR encephalitis. In addition, whether YKL-40 could indicate the disease severity was also evaluated. MethodsThe clinical features of 14 patients with anti-GABAbR encephalitis and 21 patients with anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis were retrospectively studied. YKL-40 levels in serum and cerebral fluid (CSF) of patients were detected by enzyme-linked immunosorbent assay. The correlation of modified Rankin Scale (mRS) score of encephalitis patients and YKL40 levels were analyzed. ResultsYKL-40 levels in CSF were significantly higher in patients with anti-GABAbR encephalitis or anti-NMDAR encephalitis than those in controls. YKL-40 levels between these two encephalitis groups were not different. Moreover, YKL-40 levels in CSF from patients with anti-GABAbR encephalitis were positively correlated with the mRS score at admission and at 6-month follow-up. ConclusionYKL-40 level is elevated in CSF from patients with anti-GABAbR encephalitis at early disease stage. YKL-40 may be a potential biomarker indicating the prognosis of patients with anti-GABAbR encephalitis.

Clinical characteristics and prognosis of anti-GABABR encephalitis: A single-center experience.

The purpose of this study was to assess the demographic data, clinical manifestations, cerebrospinal fluid (CSF), hematology, brain magnetic resonance imaging, electroencephalograms, and therapy and prognosis related to anti-gamma-aminobutyric acid B (anti-GABABR) encephalitis. We retrospectively examined the demographic data, clinical manifestations, laboratory results, brain magnetic resonance imaging, electroencephalograms, and therapy and prognosis of 6 patients with anti-GABABR encephalitis. We used the clinical data of patients with anti-GABABR encephalitis admitted to the Department of Neurology of Mianyang Central Hospital obtained from January 2017 to September 2020. Six patients with anti-GABABR encephalitis were included. Generalized tonic-clonic seizure was the first clinical symptom in 5 patients, while 1 patient first showed behavior disorder. After the first clinical symptom attack, 2 patients developed a memory deficit, 4 cases showed cognitive decline, 3 cases showed behavior disorder, 1 patient developed status epilepticus and only 1 patient returned to normal. CSF testing indicated normal intracranial pressure in 5 patients and elevated pressure in only 1 patient. Additionally, the cerebrospinal fluid tests revealed slight leukocytosis in all patients and elevated protein levels in 5 patients. The anti-GABABR antibody was positive in both serum and CSF in all patients. Brain magnetic resonance imaging showed limbic system lesions in 4 patients. Long-term electroencephalograms revealed abnormal waves in half of the patients. All patients were treated with high dosages of methylprednisolone, which was combined with intravenous immunoglobulin in 2 patients; symptoms were improved in 4 patients, 1 patient showed no significant change and 1 patient with status epilepticus died of severe pneumonia during hospitalization. Epilepsy is the most common initial symptom in patients of anti-GABABR encephalitis. Many patients are also affected by tumors. Early immunotherapy can achieve excellent effects, the long-term prognosis is good for most patients.

Cytokines/chemokines and soluble immune checkpoint molecules in anti-GABAB receptor encephalitis

Anti-gamma-aminobutyric-acid B receptor (anti-GABABR) encephalitis is a rare form of autoimmune limbic encephalitis (ALE) that is closely associated with tumor comorbidity. The purpose of this study is to identify the expressive pattern of cytokines/ chemokines and soluble immune checkpoint molecules (sICMs) in anti-GABABR encephalitis in order to evaluate the clinical condition and provide new treatment options. A total of 40 cytokines/chemokines and 10 sICMs in the serum of 10 patients with anti-GABABR encephalitis and eight controls were measured. The differentially expressed cytokines/chemokines and sICMs were selected to explore the correlations with disease prognosis, CSF routine and antibody titers. Eight cytokines/chemokines were found to be more abundant in patients than in healthy donors (HDs), while 14 were found to be less abundant in patients. In terms of sICMs, patients' serum contained higher level of soluble ICOS and ICOSL but lower level of soluble CD86. Unfavorable prognosis was associated with high serum level of PDGFB, IL-17A, and soluble ICOSL but not with low levels of IL-4. Increased levels of IL-17A, CCL15, and soluble ICOS were found frequently in the patients with CSF-exclusive OCBs, while soluble ICOSL and CCL24 expression was lower in these patients. High levels of IL-1 F2 and TCA-3 were correlated with the presence of tumors in patients. The majority of patients with anti- GABABR encephalitis had an unfavorable prognosis in one year of follow-up. Serum PDGFB, IL-17A, IL-4 and soluble ICOSL level were associated with the poor clinical outcomes in one-year follow up.

Clinical characteristics and prognosis of anti-γ-aminobutyric acid-B receptor encephalitis: A single-center, longitudinal study in China.

ObjectiveAnti-γ-aminobutyric acid-B receptor (GABABR) encephalitis is a rare type of autoimmune encephalitis. There are only a few, small, published studies regarding prognosis, so prediction of prognosis is of limited accuracy. We identified 37 cases of anti-GABABR encephalitis in China. Here, we present these patients' clinical characteristics and long-term outcomes.MethodsWe collected and retrospectively analyzed the clinical data of 37 patients with anti-GABABR encephalitis from Beijing Fengtai You'anmen Hospital.ResultsThe study cohort comprised 37 patients of anti-GABABR encephalitis of median age 61 years (range: 11–77), 28 of whom were male. The main clinical manifestations were epilepsy (91.9%, 34/37), psychiatric disorders (94.6%, 35/37) and cognitive impairment (97.3%, 36/37). Tumors were identified in 18 (48.6%) patients. First-line immunotherapy was administered to 34 patients, 31 of whom (90.6%) responded favorably. During a median follow-up of 18 months (range: 1–72 months), 21 patients had good outcomes [Modified Ranking Scale (mRS ≤2)], 16 (43.2%) died (mRS 6), and 7 (18.9%) relapsed. Age (P = 0.005), disturbance of consciousness (P = 0.018), admission to the Neurology Intensive Care Unit (P = 0.003), mechanical ventilation (P = 0.009), more numerous clinical manifestations (P = 0.008), comorbid malignancy (P = 0.008), multiple anti-neuronal antibodies (P = 0.029), and hyponatremia (P = 0.023) differed significantly between patients with good outcomes (mRS 0–2) and those with poor outcomes (mRS 3–6).ConclusionMen aged 50–70 years accounted for most of the patients with anti-GABABR encephalitis in our case series. The main clinical manifestations were epilepsy and neuropsychiatric dysfunction. The participants often had concomitant lung cancer, particularly small-cell lung cancer. Patients with lung tumors and/or serious manifestations usually had a poor prognosis with high mortality. Early identification and treatment of tumors improved the poor prognosis to some extent.

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

PurposeAnti-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.MethodsThirty-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.ResultsOf 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.ConclusionOur 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.

Clinical Characteristics and Short-Term Prognosis of Children With Antibody-Mediated Autoimmune Encephalitis: A Single-Center Cohort Study.

BackgroundThe incidence and prevalence of autoimmune encephalitis (AE) is gradually increasing in pediatric patients (between the ages of 3 months and 16 years). The aim of this retrospective observational study was to investigate the clinical characteristics and short-term prognosis of children with antibody-mediated AE at Hunan Children's Hospital.MethodsAntibody analysis of blood and/or cerebrospinal fluid was performed in suspected AE patients admitted to the Department of Neurology, Hunan Children's Hospital from June 2014 to June 2021. Ultimately, 103 patients were diagnosed with antibody-mediated AE and were enrolled in this study. Clinical data and corresponding demographic, clinical characteristics, laboratory and imaging data, treatment, and prognosis data were collected and analyzed.ResultsIn our study, 103 AE patients with antibody-positive were identified. The main subtype of AE in our cohort was anti-NMDAR encephalitis. Few patients have anti-CASPR2 encephalitis, anti-GABABR encephalitis, or anti-LGI1 encephalitis. In our AE patients, the most common clinical manifestations were behavioral symptoms, seizures, and involuntary movements, with seizures being the most common initial symptom. All patients underwent brain magnetic resonance imaging (MRI) and electroencephalography (EEG). Forty-five (43.7%) patients had abnormal MRI findings. And 96 (93.2%) patients had abnormal EEG results. All 103 patients were given first-line immunotherapy, 21 of which were also treated with the combination of the second-line immunotherapy. All surviving patients were followed up for at least 6 months. Seventy-seven patients recovered completely, 23 had sequelae of different degrees, and 3 died. Eight patients had one or more relapses during the follow-up period.ConclusionsAE is a treatable disease that can occur in children of all ages. The mortality rate is low, as most patients have a good response to immune therapy. Compared with the older children, infants and young children (≤ 3 years old) with anti-NMDAR encephalitis have a higher incidence of fever and status epilepticus, more severe condition, higher PICU admission rate and worse prognosis. AE patients with high maximum mRS scores and PICU admissions may require second-line immunotherapy.

Relapses of Anti-NMDAR, Anti-GABABR and Anti-LGI1 Encephalitis: A Retrospective Cohort Study.

ObjectiveTo investigate the relapse rate and study the factors that may predict the subsequent relapse in anti-NMDAR, anti-GABABR and anti-LGI1 encephalitis in Northeast China.MethodsIn the retrospective cohort study, we consecutively enrolled patients with anti-N1MDAR, anti-GABABR and anti-LGI1 encephalitis between March 2015 and November 2021. The patients were followed up for at least 6 months. The outcome variable was a binary variable of relapse or not. Predictors of relapse were identified.ResultsA total of 100 patients were enrolled. Relapse occurred in 26 (26%) patients after a median follow-up of 18 months since the first event. The relapse rates of anti - NMDAR, anti - GABABR and anti - LGI1 encephalitis were 25%, 33.3%, and 28.6%, respectively. The multivariable analysis results suggested that immunotherapy delay at the acute phase was independently associated with an increased risk of relapse in total patients (HR = 2.447, 95% CI = 1.027 - 5.832; P = 0.043). Subgroup analysis results showed that antibody titer was associated with the likelihood of relapse in anti-LGI1 encephalitis. The higher the concentration, the more likely it was for patients to have relapse (p=0.019).ConclusionThe general relapse rate of anti-NMDAR, anti-GABABR and anti-LGI1 encephalitis was 26%. The risk of subsequent relapse was elevated in those with delayed immunotherapy in the first episode. In subgroup of anti-LGI1 encephalitis, higher antibody titer was the risk factors of relapse. Thus, timely and aggressive immunotherapy may be beneficial for patients to prevent subsequent relapse.

A Prognostic Analysis of the Outcomes in Patients With Anti-γ-Aminobutyric Acid B Receptor Encephalitis.

ObjectiveTo evaluate neurological function and its influencing factors in patients with anti-γ -aminobutyric acid B receptor (GABABR) encephalitis.MethodsThis was a clinical cohort study of patients diagnosed with anti-GABABR encephalitis; long-term follow-up was performed by telephone. Clinical factors associated with prognosis were analyzed, including clinical manifestations, laboratory examinations, imaging features, tumor comorbidities and therapeutic responses.ResultsTwenty-two patients with anti-GABABR encephalitis were evaluated (median age: 55 years). Lung cancer was detected in eight patients. All were with serum tumor markers (mainly NSE), and three of them had additional onconeuronal antibodies. The patients with tumors were older than the patients without tumors and more likely to develop status epilepticus (62.5% vs. 14.3%; p = 0.052), central hypoventilation (50% vs. 7.1%; p = 0.039), and hyponatremia (87.5% vs. 14.3%; p = 0.001). The patients with tumors had higher mortality (87.5% vs. 0%; p < 0.05). Although 92.9% of the patients without tumors became functionally independent (mRS ≤2), sequelae of symptomatic seizures, neuropsychiatric symptoms, and cognitive impairment were still observed in 14.3%, 21.4%, and 21.4% of patients, respectively.Conclusions(1) Elderly patients with anti-GABABR antibodies, especially those with severe symptoms, serum tumor markers, and additional onconeuronal antibodies, should be screened for lung cancer. (2) Anti-GABABR encephalitis with tumors has a poor prognosis. (3) Most patients without tumors achieve self-care, but some still experience remaining neurological deficits.

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

ObjectiveWe aimed to investigate the mortality rate and identify the predictors of death in patients with anti-NMDAR, anti-LGI1, and anti-GABABR encephalitis.MethodsPatients 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.ResultsA 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).ConclusionThe 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.

Clinical characteristics and elevated ProGRP and positive oligoclonal bands of 13 Chinese cases with anti-GABABR encephalitis.

To improve the clinical understanding of anti-gamma-aminobutyric-acid B receptor encephalitis (anti-GABABR encephalitis) by analyzing 13 cases. We retrospectively studied demographic and clinical features including clinical symptoms, serum/cerebrospinal fluid (CSF) laboratory findings (including antibody test), brain magnetic resonance imaging (MRI), electroencephalogram (EEG), treatment plan, and treatment effect for 13 patients with a definitive diagnosis of anti-GABABR encephalitis. Seven patients (53.8%, 7/13) were complicated with lung cancer. Epileptic seizures were the most common symptoms at onset in 11 patients (84.6%, 11/13). All patients had seizures in the course of the disease. Abnormalities in craniocerebral MRI examination, including hippocampus, occipital lobe, insular lobe, were found in six of nine tested patients, and EEG abnormalities were found in seven out of nine tested patients. Elevated pro-gastrinreleasingpeptide (ProGRP) levels were found in 70% of patients with a median value of 490.10pg/ml; and CSF oligoclonal bands were positive for 4 of 10 tested cases. However, there were no significant differences in modified Rankin Scale (mRS) between the ProGRP or CSF oligoclonal band positive and negative groups at admission and follow-up (p>.05). The value between SCLC and non-SCLC subgroup was significantly different (p<.05). Ten patients received immunotherapy (three patients refused treatment). After immunotherapy, the frequency of seizures was significantly reduced. There was a significant difference in mRS between admission and after treatment (p<.05). The average survival time after onset was 27.7months. Epilepsy is the most common clinical manifestation of Anti-GABABR encephalitis. The prognosis of anti-GABABR encephalitis is poor. Section of anti-GABABR encephalitis patients have higher level of serum ProGRP and positive GSF oligoclonal bands. Elevated ProGRP or positive CSF oligoclonal bands with classic clinical features can potentially help to improve early recognition of anti-GABABR encephalitis.

The long\u2010term outcome of neuropsychological function is favorable in patients with non\u2010malignancy related anti-GABABR encephalitis: a case series

BackgroundAnti-GABABR encephalitis is a rare type of autoimmune encephalitis, which often presents with memory impairments, behavioral changes and seizures. This case series describes the neuropsychological function recovery pattern in five adult patients with anti-GABABR encephalitis.Case presentationWe recruited five patients with clinically confirmed anti-GABABR encephalitis without any accompanying malignancy. Comprehensive neuropsychological evaluation was conducted on each patient. All the five patients were evaluated in the chronic phase. Five age and gender matched healthy adults were recruited as control group. Our study demonstrated that the neuropsychological function of the patients with anti-GABABR encephalitis was no different with respect to the control group during the chronic phase (more than 6 months after onset). Moreover, one patients with neuropsychological evaluation at acute (within 2 months after onset of symptoms), post-acute (2 to 6 months after onset) and chronic phases respectively, presented neuropsychological function recovered as early as in the post-acute phase and only showed cognition impairment in the acute phase.ConclusionsThe results of this retrospective study indicate a favorable long-term neuropsychological function outcome in adult patients with anti-GABABR encephalitis, despite severe memory deficits occurring during the acute phase. These findings improve our understanding related to the prognosis of neuropsychological function in anti-GABABR encephalitis.

Long-term cognitive and neuropsychiatric outcomes of anti-GABABR encephalitis patients: A prospective study

Long-term cognitive and neuropsychiatric outcomes of anti-gamma-aminobutyric-acid B receptor (anti-GABABR) encephalitis are unclear. In this prospective study, 31 patients with anti-GABABR encephalitis were underwent cognitive and neuropsychiatric evaluations every 6 months. At 24 months' follow-up, cognitive impairments were observed in 80% of patients that mainly included deficits in memory, executive functions and nonverbal reasoning; and neuropsychiatric symptoms were observed in 50% of patients that mainly included depressive symptoms and irritation. The risk factors associated with cognitive deficits was age > 45 years. This study demonstrated that most patients with anti-GABABR encephalitis had persistent cognitive deficits and neuropsychiatric symptoms.

Direct economic burden of patients with autoimmune encephalitis in western China.

ObjectiveTo analyze the cost of autoimmune encephalitis (AE) in China for the first time.MethodsPatients who were newly diagnosed with antibody-positive AE (anti-NMDA receptor [NMDAR], anti-γ aminobutyric acid type B receptor [GABABR], antileucine-rich glioma-inactivated 1 [LGI1], and anticontactin-associated protein-2 [CASPR2]) at West China Medical Center between June 2012 and December 2018 were enrolled, and a cost-of-illness study was performed retrospectively. Data on clinical characteristics, costs, and utilization of sources were collected from questionnaires and the hospital information system.ResultsOf the 208 patients reviewed, the mean direct cost per patient was renminbi (RMB) 94,129 (United States dollars [USD] 14,219), with an average direct medical cost of RMB 88,373 (USD 13,349). The average inpatient cost per patients with AE was RMB 86,810 (USD 13,113). The direct nonmedical cost was much lower than the direct medical cost, averaging RMB 5,756 (USD 869). The direct cost of anti-LGI1/CASPR2 encephalitis was significantly lower than that of anti-NMDAR encephalitis and anti-GABABR encephalitis. The length of stay in the hospital was significantly associated with the direct cost.ConclusionsThe financial burden of AE is heavy for Chinese patients, and there are significant differences between different types of AE.