Efficacy of Therapeutic Plasma Exchange in Patients with Severe Refractory Anti-NMDA Receptor Encephalitis

Suspected autoimmune encephalitis: A retrospective study of patients referred for therapeutic plasma exchange

INTRODUCTION

Autoimmune encephalitis (AE) comprises a heterogeneous group of autoantibody-mediated disorders targeting the brain parenchyma. Therapeutic plasma exchange (TPE), one of several first-line therapies for AE, is often initiated when AE is suspected, albeit prior to an established diagnosis. We sought to characterize the role of TPE in the treatment of suspected AE.

METHODS

A single-center, retrospective analysis was performed of adults (≥18 years) who underwent at least one TPE procedure for "suspected AE." The following parameters were extracted and evaluated descriptively: clinicopathologic characteristics, treatment course, TPE-related adverse events, outcomes (e.g., modified Rankin scale [mRS]), and diagnosis once investigation was complete.

RESULTS

A total of 37 patients (median age 56 years, range 28-77 years, 62.2% male) were evaluated. Autoimmune antibody testing was positive in serum for 43.2% (n = 16) and cerebrospinal fluid for 29.7% (n = 11). Patients underwent a median of five TPE procedures (range 3-16), with 97.3% (n = 36) via a central line and 21.6% (n = 8) requiring at least one unit of plasma as replacement fluid. Fifteen patients (40.5%) experienced at least one TPE-related adverse event. Compared with mRS at admission, the mRS at discharge was improved in 21.6% (n = 8), unchanged in 59.5% (n = 22), or worse in 18.9% (n = 7). Final diagnosis of AE was determined to be definite in 48.6% (n = 18), probable in 8.1% (n = 3) and possible in 27.0% (n = 10). Six (16.2%) patients were ultimately determined to have an alternate etiology.

CONCLUSION

Empiric TPE for suspected AE is generally well-tolerated. However, its efficacy remains uncertain in the absence of controlled trials, particularly in the setting of seronegative disease.

Canadian Consensus Guidelines for the Diagnosis and Treatment of Autoimmune Encephalitis in Adults

Autoimmune encephalitis is increasingly recognized as a neurologic cause of acute mental status changes with similar prevalence to infectious encephalitis. Despite rising awareness, approaches to diagnosis remain inconsistent and evidence for optimal treatment is limited. The following Canadian guidelines represent a consensus and evidence (where available) based approach to both the diagnosis and treatment of adult patients with autoimmune encephalitis. The guidelines were developed using a modified RAND process and included input from specialists in autoimmune neurology, neuropsychiatry and infectious diseases. These guidelines are targeted at front line clinicians and were created to provide a pragmatic and practical approach to managing such patients in the acute setting.

Surgical procedures and plasma exchange for ovarian teratoma-associated anti-N-methyl D-aspartate receptor encephalitis: a case report and review of literature

We reported a case of ovarian teratoma-associated Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis with recurrent epileptic seizures and disturbance of consciousness. Although surgical excision of the tumor remains the established standard of care, unlike other reported cases, the patient exhibited limited response to early oophorocystectomy, as well as IVIG and steroid therapy; however, a favorable response was observed with Plasma exchange (PE) initiated on postoperative day 12. Literature review revealed no definite recommended surgical extent for ovarian teratomas, and outstanding improvement in patients with anti-NMDAR encephalitis following PE. Our case raises the question regarding the optimal surgical extent for tumor resection, necessitating careful consideration when deciding between oophorectomy and adnexectomy as the preferred surgical procedure for anti-NMDAR encephalitis in female teens and adults. Furthermore, for refractory patients who fail to respond following tumor resection, PE can be performed early instead of immediately initiating second-line therapy.

Controversies in immunotherapy for anti-NMDA receptor encephalitis: a scoping review with a proposal of operational definitions

Anti-NMDA receptor encephalitis (NMDARE), an autoimmune encephalitis associated with autoantibodies against the N-methyl-D-aspartate (NMDA) receptor, affects predominantly young women and is associated with psychiatric symptoms, seizures, movement disorders, and autonomic instability. Traditional treatments of anti-NMDA receptor encephalitis involve corticosteroids, intravenous immunoglobulin, plasmapheresis, cyclophosphamide, and rituximab. However, many controversies remain in the treatment for NMDA receptor encephalitis, such as optimal timing and combination of different immunotherapies, the role of newer strategies (e.g., bortezomib or tocilizumab) for severe and refractory patients, and the need or not for long-term immunosuppression. Our goal was to perform a scoping review to discuss the controversial topics of immunotherapy for NMDA receptor encephalitis and propose operational definitions to guide clinical practice and future research in the field.

Long-term efficacy and safety of different corticosteroid courses plus mycophenolate mofetil for autoimmune encephalitis with neuronal surface antibodies without tumor

Objective

To compare the efficacy and safety of different-course corticosteroids plus mycophenolate mofetil (MMF) as maintenance therapy in autoimmune encephalitis (AE) with neuronal surface antibodies (NSAbs) without tumor and explore the optimal course of corticosteroids.

Methods

Fifty-five patients with definite AE without tumor were enrolled consecutively between June 2015 and November 2020 and retrospectively divided three groups according to the course of treatment with corticosteroid, i.e., a group of patients with a course of 3-6 months (Group 3-6mo), 6-12 months (Group 6-12mo), and >12 months (Group >12mo). Demographic data, clinical manifestation and ancillary tests results were recorded. The dosage and courses of corticosteroid treatment, the recovery of neurological function, the occurrence of adverse effects, and relapses were followed up.

Results

A total of 55 patients were included in the final analysis. The numbers of patients in Group 3-6 mo, Group 6-12 mo, and Group >12 mo was 14, 17, and 24, respectively. A significantly higher proportion of patients in Group >12 mo showed a decreased level of consciousness at the onset (12, 50%) than in Group 3-6 mo and Group 6-12 mo (2,14.3%; 3, 17.6%) (p = 0.033). The incidence of MRI abnormalities was significantly higher in Group 6-12 mo and Group >12 mo (10, 58.8%; 16, 66.7%) than in Group 3-6 mo (3, 21.4%) (P=0.023). Ordinal regression analysis indicated that decreased level of consciousness was associated with the course of corticosteroid (OR=3.838, 95% CI: 1.103-13.323, P=0.035). No significant difference was observed between the three groups regarding the cumulative dose of corticosteroids administered during the first three months of long-term treatment (P>0.05). Additionally, no significant difference in the cumulative dosage of corticosteroids was found between patients in Group 6-12 months and Group >12 months during the first 6 months after beginning long-term treatment. The mRS scores of the three groups were not statistically significant before and after first-line treatment or at the last follow-up. Bonferroni multiple comparison test indicated that the mRS scores of patients in Group 6-12 months and Group >12 months were not statistically significant at 3 months and 12 months after the start of long-term treatment. During the follow-up, 50 (90.9%) patients achieved satisfactory neurological function (mRS score ≤2). Five patients (9.1%) experienced a first relapse and 2 of them were overlapped with both anti-NMDA receptor and glial antibodies. The incidence of adverse effects was significantly higher in Group >12 mo (17, 70.8%) than in Group 3-6 mo (3, 21.4%) and Group 6-12 mo (5, 29.4%) (P=0.003).

Conclusions

The beneficial effects of oral corticosteroid treatment may do not persist beyond 12 months and may even contribute to an increased incidence of adverse effects. In order to optimize the effectiveness and safety of treatment, we recommend a corticosteroid course of 3-12 months. Patients with reduced levels of consciousness may be more inclined to choose longer courses of corticosteroids for long-term treatment. Patients with an "overlapping syndrome" may require more intense immunotherapy to prevent relapse.

Therapeutic plasma exchange in anti-N-methyl-D-aspartate receptor encephalitis

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is the most commonly identified cause of autoimmune encephalitis. Therapeutic plasma exchange has been increasingly employed to treat this disease. This expansion is a consequence of improved techniques and apheresis instruments, as well as the recognition of its applicability in neurological diseases. However, several aspects of treatment remain incompletely clarified, and treatment strategies are still heterogeneous, especially with regard to therapeutic plasma exchange in anti-NMDAR encephalitis. This review provides an overview of the use of therapeutic plasma exchange including the principle and mechanisms, the evidence, initial time, efficiency and complications in anti-NMDAR encephalitis.

From bedside to bench: how existing therapies inform the relationship between Epstein-Barr virus and multiple sclerosis

Therapy for relapsing-remitting multiple sclerosis (MS) has advanced dramatically despite incomplete understanding of the cause of the condition. Current treatment involves inducing broad effects on immune cell populations with consequent off-target side effects, and no treatment can completely prevent disability progression. Further therapeutic advancement will require a better understanding of the pathobiology of MS. Interest in the role of Epstein-Barr virus (EBV) in multiple sclerosis has intensified based on strong epidemiological evidence of an association between EBV seroprevalence and MS. Hypotheses proposed to explain the biological relationship between EBV and MS include molecular mimicry, EBV immortalised autoreactive B cells and infection of glial cells by EBV. Examining the interaction between EBV and immunotherapies that have demonstrated efficacy in MS offers clues to the validity of these hypotheses. The efficacy of B cell depleting therapies could be consistent with a hypothesis that EBV-infected B cells drive MS; however, loss of T cell control of B cells does not exacerbate MS. A number of MS therapies invoke change in EBV-specific T cell populations, but pathogenic EBV-specific T cells with cross-reactivity to CNS antigen have not been identified. Immune reconstitution therapies induce EBV viraemia and expansion of EBV-specific T cell clones, but this does not correlate with relapse. Much remains unknown regarding the role of EBV in MS pathogenesis. We discuss future translational research that could fill important knowledge gaps.

Anti-NMDA Receptor Autoimmune Encephalitis: Diagnosis and Management Strategies

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is the most recognized form of autoimmune encephalitis. It is characterized by a constellation of neurologic and psychiatric features along with positive NMDAR antibody, which is more sensitive and specific in CSF than serum. All patients should be screened at least once for neoplasm, with ovarian teratoma being found in most tumor-related cases. In the acute phase, first-line immunotherapy, often a combination of high-dose steroids, immunoglobulins, and/or plasma exchange, is strongly recommended. When first-line therapy fails, escalation to second-line immunotherapy, particularly rituximab, can further improve outcomes and prevent relapses. In refractory cases, additional complementary immunotherapies, such as cyclophosphamide, bortezomib and/or tocilizumab may be considered. Relapses occur in 10-30% of cases, mostly within the first two years from onset. Individuals should be followed up to determine if chronic maintenance therapy is required.

Temporal Dynamics of MOG Antibodies in Children With Acquired Demyelinating Syndrome

Background and Objective

The spectrum of myelin oligodendrocyte glycoprotein (MOG) antibody–associated disorder (MOGAD) comprises monophasic diseases such as acute disseminated encephalomyelitis (ADEM), optic neuritis (ON), and transverse myelitis and relapsing courses of these presentations. Persistently high MOG antibodies (MOG immunoglobulin G [IgG]) are found in patients with a relapsing disease course. Prognostic factors to determine the clinical course of children with a first MOGAD are still lacking. The objective of the study is to assess the clinical and laboratory prognostic parameters for a risk of relapse and the temporal dynamics of MOG‐IgG titers in children with MOGAD in correlation with clinical presentation and disease course.

Methods

In this prospective multicenter hospital-based study, children with a first demyelinating attack and complete data set comprising clinical and radiologic findings, MOG-IgG titer at onset, and clinical and serologic follow-up data were included. Serum samples were analyzed by live cell-based assay, and a titer level of ≥1:160 was classified as MOG-IgG–positive.

Results

One hundred sixteen children (f:m = 57:59) with MOGAD were included and initially diagnosed with ADEM (n = 59), unilateral ON (n = 12), bilateral ON (n = 16), myelitis (n = 6), neuromyelitis optica spectrum disorder (n = 8) or encephalitis (n = 6). The median follow-up time was 3 years in monophasic and 5 years in relapsing patients. There was no significant association between disease course and MOG-IgG titers at onset, sex, age at presentation, or clinical phenotype. Seroconversion to MOG-IgG–negative within 2 years of the initial event showed a significant risk reduction for a relapsing disease course. Forty-two/one hundred sixteen patients (monophasic n = 26, relapsing n = 16) had serial MOG-IgG testing in years 1 and 2 after the initial event. In contrast to relapsing patients, monophasic patients showed a significant decrease of MOG-IgG titers during the first and second years, often with seroconversion to negative titers. During the follow-up, MOG-IgG titers were persistently higher in relapsing than in monophasic patients. Decrease in MOG-IgG of ≥3 dilution steps after the first and second years was shown to be associated with a decreased risk of relapses. In our cohort, no patient experienced a relapse after seroconversion to MOG-IgG–negative.

Discussion

In this study, patients with declining MOG-IgG titers, particularly those with seroconversion to MOG-IgG–negative, are shown to have a significantly reduced relapse risk.

Recent research on immunotherapy for anti-N-methyl-D-aspartate receptor encephalitis

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a central nervous system disease characterized by neurological and psychiatric symptoms. Immunotherapy is the basic treatment for this disease, including first- and second-line therapies for the acute stage and the long-course therapy for the chronic stage. Anti-NMDAR encephalitis often has a good prognosis, but some patients may still have neurological dysfunction due to poor response to current immunotherapy. In addition, the adverse reactions and economic burden of drugs are practical problems in clinical practice. To solve the above problems, continuous improvements have been made in immunotherapy regimens in terms of dose, route of administration, and course of treatment, and some new immunotherapy drugs have emerged. This article reviews the recent research on immunotherapy for anti-NMDAR encephalitis.

Lymphoplasma Exchange Improves Myasthenia Gravis Exacerbations: A Retrospective Study in a Chinese Center

Background

Lymphoplasma exchange (LPE), a technique combining plasma exchange with leukapheresis, is emerging as promising treatment for autoimmune diseases. Data on the efficacy and safety of LPE in myasthenia gravis (MG) therapy are scarce. In this study, we aimed to comprehensively review the clinical efficacy, safety, and immunological characteristics of LPE therapy in MG patients.

Study Design and Methods

A Chinese cohort of 276 generalized MG patients in state of exacerbation, including impeding crisis, myasthenia crisis, and preparation for thoracic exsection between January 2014 and December 2020, were evaluated in this study.

Results

A total of 276 patients with a median age of 45.5 ± 16.7 years underwent a total of 635 LPE sessions. Clinical scales of Quantitative Myasthenia Gravis (QMG) scores, Myasthenia Gravis Specific Manual Muscle Testing (MMT) scores, activities of daily living (ADL) scores, and quality of life (QOL) scores were improved during 4 weeks’ follow-up. Adverse effects occurred in 20 out of 276 patients, with 14 patients having one adverse event each. Independent predictive factors for good response to LPE therapy were symptom onset before LPE therapy ≤3 days and age on LPE therapy <50 years of age. LPE decreased the serum levels of antibodies, immunoglobulins, and complements 4 weeks after the first replacement, with decreased levels of interleukin (IL)-17A and interferon (IFN)-γ and increased level of IL-10.

Conclusion

LPE is an effective treatment for MG patients in state of exacerbation and preparation for thymectomy. Early use of LPE on early-onset MG may have good therapeutic effects. The potential mechanism for LPE is the polarization of cytokines from IL-17A, IFN-γ, into IL-10.

Diagnostic approach and treatment regimens in adult patients suffering from antibody-mediated or paraneoplastic encephalitis

Identification of patients with antibody-mediated encephalitis poses a diagnostic challenge and any delay in that respect will increase the interval until initiation of immunotherapy and may negatively affect the patient´s clinical outcome. Within this review we focus on therapeutic strategies in antibody-mediated encephalitis and propose how to proceed with patients, who are suspected to have encephalitis of unknown origin. We further briefly outline differences in treatment of paraneoplastic and antibody-mediated encephalitis according to its pathomechanisms.

Use and Safety of Immunotherapeutic Management of N-Methyl-d-Aspartate Receptor Antibody Encephalitis: A Meta-analysis

Question

What are the most effective treatments for N-methyl-d-aspartate receptor (NMDAR) antibody encephalitis?

Findings

In this meta-analysis of individual patient data including 1550 cases, treatment factors at first event that were significantly associated with good functional outcome 12 months from disease onset included first-line treatment with therapeutic apheresis alone, corticosteroids in combination with intravenous immunoglobulin (IVIG), or corticosteroids in combination with IVIG and therapeutic apheresis, while lack of immunotherapy within 30 days of disease onset was significantly associated with poor outcome. Rituximab and long-term IVIG use were significantly associated with nonrelapsing disease course.

Meaning

Separate treatment factors are associated with functional outcomes and relapsing disease biology in those with NMDAR antibody encephalitis.

Importance

Overall, immunotherapy has been shown to improve outcomes and reduce relapses in individuals with N-methyl-d-aspartate receptor (NMDAR) antibody encephalitis (NMDARE); however, the superiority of specific treatments and combinations remains unclear.

Objective

To map the use and safety of immunotherapies in individuals with NMDARE, identify early predictors of poor functional outcome and relapse, evaluate changes in immunotherapy use and disease outcome over the 14 years since first reports of NMDARE, and assess the Anti-NMDAR Encephalitis One-Year Functional Status (NEOS) score.

Data Sources

Systematic search in PubMed from inception to January 1, 2019.

Study Selection

Published articles including patients with NMDARE with positive NMDAR antibodies and available individual immunotherapy data.

Data Extraction and Synthesis

Individual patient data on immunotherapies, clinical characteristics at presentation, disease course, and final functional outcome (modified Rankin Scale [mRS] score) were entered into multivariable logistic regression models.

Main Outcomes and Measures

The planned study outcomes were functional outcome at 12 months from disease onset (good, mRS score of 0 to 2; poor, mRS score greater than 2) and monophasic course (absence of relapse at 24 months or later from onset).

Results

Data from 1550 patients from 652 articles were evaluated. Of these, 1105 of 1508 (73.3%) were female and 707 of 1526 (46.3%) were 18 years or younger at disease onset. Factors at first event that were significantly associated with good functional outcome included adolescent age and first-line treatment with therapeutic apheresis, corticosteroids plus intravenous immunoglobulin (IVIG), or corticosteroids plus IVIG plus therapeutic apheresis. Factors significantly associated with poor functional outcome were age younger than 2 years or age of 65 years or older at onset, intensive care unit admission, extreme delta brush pattern on electroencephalography, lack of immunotherapy within the first 30 days of onset, and maintenance IVIG use for 6 months or more. Factors significantly associated with nonrelapsing disease were rituximab use or maintenance IVIG use for 6 months or more. Adolescent age at onset was significantly associated with relapsing disease. Rituximab use increased from 13.5% (52 of 384; 2007 to 2013) to 28.3% (311 of 1100; 2013 to 2019) (P < .001), concurrent with a falling relapse rate over the same period (22% [12 of 55] in 2008 and earlier; 10.9% [35 of 322] in 2017 and later; P = .006). Modified NEOS score (including 4 of 5 original NEOS items) was associated with probability of poor functional status at 1 year (20.1% [40 of 199] for a score of 0 to 1 points; 43.8% [77 of 176] for a score of 3 to 4 points; P = .05).

Conclusions and Relevance

Factors influencing functional outcomes and relapse are different and need to be considered independently in development of evidence-based optimal management guidelines of patients with NMDARE.

Understanding Seizures and Prognosis of the Extreme Delta Brush Pattern in Anti-N-Methyl-D-Aspartate (NMDA) Receptor Encephalitis: A Systematic Review

Anti-N-methyl-d-aspartate (NMDA) receptor encephalitis (ANMDARE) is an autoimmune disorder with neurological and psychiatric features. The disease presents with a viral prodrome, followed by psychiatric manifestations. In the next phase, movement disorders or/and seizures occur. Finally, in the last phase, there is a decrease in the level of consciousness. Central hypoventilation and autonomic dysfunction can occur. Recently a unique EEG (electroencephalogram) pattern has been associated with anti-NMDA receptor encephalitis, the extreme delta brush (EDB). Although the association of the EDB with ANMDARE is known by the medical community, its significance is mainly unknown. A systematic review on NMDARE is also scarce. We decided to conduct a systematic review on this topic to consolidate the knowledge and establish the importance of the EDB as a prognostic factor. To conduct this systematic review, we used only studies conducted in humans, written in English, and published in the last 20 years. We used PubMed as a database and searched the following search terms: ("NMDA encephalitis"[Title/Abstract] AND "Epilepsy"[Title/Abstract]) OR (NMDA encephalitis"[Title/Abstract] AND "seizures" [Title/Abstract]) OR ("NMDA encephalitis"[Title/Abstract] AND "extreme delta brush"[Title/Abstract]). The protocol used for this systematic review was the Meta-analyses Of Observational Studies in Epidemiology (MOOSE) protocol, and to analyze the bias of the studies, we used the ROBINS-1 tool. Eight studies were collected from our search strategy. Our data pulling showed that seizures were present in 178/249 (71.48%) patients. Status Epilepticus was reported in 29/96 (30.20%), and the EBD was seen in 30.89% (55/178) patients with seizures. The range of EDB was 5.9%-33% among the studies. Because the sample size was small, the statistical power was decreased. We had a low overall risk of bias. The wide range in the results could be related to the timing of the EEG recording. EDB was associated overall with increased length of hospital stay, increased ICU admission, and incidence of status epilepticus. The etiology of the EDB remains mainly unknown. However, it has been postulated that in NMDAR encephalitis, there is a disruption of the rhythmic neuronal activity. When antibodies block/target the NMDAR, the rhythmic neuronal activity is disrupted, leading to the unique EDB pattern. Another theory suggests that delta activity is caused because of focal abnormalities in the brain, and the superimposition of the beta waves is related to the alterations of the NMDA receptors.

Protein A immunoadsorption for the treatment of refractory anti-N-methyl-d-aspartate receptor encephalitis: A single-center prospective study

OBJECTIVE

The aim of this study was to evaluate the efficacy and safety of protein A immunoadsorption (IA) for anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis resistant to intravenous methylprednisolone (IVMP) and intravenous immunoglobulin (IVIG).

METHODS

We prospectively evaluated patients with refractory anti-NMDAR encephalitis, treated with protein A IA. Demographic data, clinical characteristics, modified Rankin Score (mRS), and anti-NMDAR antibodies were documented before and after IA and at follow-up. Clinical improvement was defined as a decrease of mRS ≥1. Adverse events were recorded throughout the study.

RESULTS

Ten patients with mRS ≥3 were enrolled and treated with protein A IA; treatment was performed for an average of 5.2 times per patient. Among the nine patients with positive serum anti-NMDAR, the titer decreased in seven patients, of which two became negative. The cerebrospinal fluid (CSF) anti-NMDAR titer decreased in all patients, and one became negative. Anti-NMDAR levels were tested in two patients at follow-up and found to have declined continuously. All patients exhibited clinical improvement with a mRS decline ≥1 after IA treatment (median mRS: 5.0 [range, 3.0-5.0] vs. 4.0 [range, 2.0-4.0], p = 0.014), and the median mRS decreased to 1.0 (range, 0-3.0) at follow-up. After IA, all patients exhibited accelerated recovery. No adverse events were observed during IA treatment.

CONCLUSION

Protein A IA may be effective for treating IVMP/IVIG-resistant anti-NMDAR encephalitis and well tolerated. It is necessary to initiate larger-scale prospective controlled studies to validate the efficacy and safety of protein A IA in anti-NMDAR encephalitis.

Variable response to therapeutic plasma exchange in pediatric anti-NMDA receptor encephalitis

INTRODUCTION

Anti-NMDA receptor encephalitis in an acute form generally presents with abnormal movements and psychiatric symptoms. Therapeutic plasma exchange has been considered to be one of the first line treatment options. This report highlights the role of plasma exchange in anti-NMDA receptor encephalitis in pediatric patients.

METHODS

This is a retrospective analysis of four cases of a severe form of encephalitis due to anti-NMDA receptor antibody. All these four patients were evaluated for clinical and laboratory profile before plasma exchange. Plasma exchange was performed with Cobe Spectra Version 7.0(Terumo BCT, USA), and 5% albumin and fresh frozen plasma were used as replacement fluid.

RESULTS

A total of 20 procedures (range: 2-8/patient) were performed on four patients on an alternate day basis. Slow recovery and long-term hospitalization (range: 25-70 days) was observed in all these patients and may be due to delayed initiation of plasma exchange. One patient was lost in follow up while another one had fatal consequences after one month of discharge from the hospital.

CONCLUSION

Early diagnosis and timely initiation of therapeutic plasma exchange along with immunosuppressive therapy hasten the recovery, duration of hospitalization and yield a better outcome.

Efficacy and safety of bortezomib in rituximab-resistant anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis as well as the clinical characteristics: An observational study

Treatment resistance leads to physiological, psychological, and economical effects among patients with anti-N-methyl d-aspartate receptor (anti-NMDAR) encephalitis, and the clinical and immune characteristics of these patients remain to be described. According to our clinical experience, bortezomib may be effective due to its plasma-cells depletion ability. Herein, the clinical presentations and immune parameters, including B cell and antibody secreting cell (ASC) abundance, of 5 enrolled treatment-resistant patients are described. When compared with 5 treatment-sensitive cases, the patients had serious clinical presentations but comparable B cells and ASCs. After receiving bortezomib, the ASC count and anti-NMDAR antibody titers decreased effectively. All 5 patients had a favorable prognosis (mRS ≤ 2) with a median follow-up of 31 months without severe side effects or relapse.

Clinical efficacy of plasma exchange in patients with autoimmune encephalitis

Objective

To determine the clinical and antibody response after therapeutic plasma exchange (TPE) in patients with severe refractory antibody‐associated autoimmune encephalitis (AE).

Methods

This single‐center prospective cohort included all patients consecutively admitted to our hospital because of severe refractory AE over the period from July 2014 to June 2019. All patients received immunotherapy (steroids, intravenous immunoglobulin (IVIG), and/or TPE). The primary outcome was evaluated at 1‐ and 2‐month postenrollment, and the long‐term outcome was followed up at 6 and 12 months. AE antibody titers in the cerebrospinal fluid and plasma were evaluated before and after TPE/IVIG.

Results

This study enrolled 57 patients with severe refractory AE, including anti‐NMDA receptor encephalitis (n = 51), anti‐GABAb receptor encephalitis (n = 3), anti‐LGI 1 encephalitis (n = 2), and anti‐AMPA receptor encephalitis (n = 1). Of all 57 patients, 33 patients received TPE for a total of 193 procedures, and 24 patients with contraindications or refusal of TPE were in the non‐TPE group. Compared with the non‐TPE group, the TPE group exhibited greater clinical improvement: 21 (37%) versus 8 (14%) after 1 month (P = 0.03) and 31 (54%) versus 16 (28%) after 2 months (P = 0.01), respectively. Complications and adverse events associated with TPE occurred in 91 procedures (47%) without serious adverse events associated with the use of TPE.

Interpretation

TPE might be an effective rescue therapy associated with rapid functional improvement in patients with severe steroid/IVIG refractory antibody‐associated AE from this nonrandomized control trial.

Protein A Immunoadsorption Relieves Autoimmune Glial Fibrillary Acidic Protein Astrocytopathy after Unsuccessful Methylprednisolone Treatment

BACKGROUND

Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy (GFAP-A) is a recently defined autoimmune inflammatory disease of the central nervous system in which GFAP IgG is present in the cerebrospinal fluid (CSF). Its primary clinical manifestation is meningoencephalitis, and it usually responds well to corticosteroids. Herein, we report a case of a patient with GFAP-A with initial symptoms of psychological and cognitive impairment, which did not respond to high-dose methylprednisolone therapy but was successfully treated with protein A immunoadsorption (PAIA) therapy.

METHODS

GFAP IgG was detected by indirect immunofluorescence assay. The patient's data were analyzed retrospectively.

RESULTS

A 48-year-old man presented with anxiety, depression, cognitive decline, tremor, gait disturbance, and fecal and urine incontinence. Autoimmune GFAP-A was diagnosed based on the following: (1) T2-weighted and fluid-attenuated inversion recovery MRI findings of hypersensitive lesions in the subcortical and deep white matter of the brain, with multiple longitudinally extensive lesions in the cervical and chest regions of the spinal cord, and (2) high levels of GFAP IgG in the CSF. Clinical symptoms and abnormalities detected on neuroimaging worsened after administration of high-dose intravenous methylprednisolone (IVMP) and intravenous immunoglobulin (IVIG) but improved significantly after PAIA therapy.

CONCLUSION

Psychological impairment can be the first sign of autoimmune GFAP-A. PAIA might be an effective treatment for patients with GFAP-A who respond poorly to conventional IVMP and IVIG therapy.

Not Your Average Seizure: A Case of N-Methyl-D-Aspartate Receptor Encephalitis and Review of Literature

Encephalitis is an inflammatory process of the brain that is most commonly related to infectious etiology; nonetheless, autoimmune encephalitis has been an increasingly identified entity that can cause it as well and should be considered. N-methyl-D-aspartate (NMDA) receptor encephalitis is a recently identified process but remains less recognized than autoimmune encephalitis. We report a case of an 18-year old female who initially presented with seizures and later developed behavioral symptoms of agitation, crying, screaming, and emotional lability. Ultimately, she was found to have NMDA receptor encephalitis related to ovarian paraneoplastic teratoma. The patient was treated with anti-epileptics and intravenous immunoglobulin and underwent oophorectomy that lead to her recovery. This case highlights the importance of early recognition of NMDA receptor encephalitis to facilitate appropriate investigations and management.

Anti-N-methyl-D-aspartate receptor encephalitis: A review of pathogenic mechanisms, treatment, prognosis

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is a treatable autoimmune disorder characterized by prominent neuropsychiatric symptoms that predominantly affects children and young adults. In this review, we discuss the pathogenic mechanisms and immunologic triggers of anti-NMDAR encephalitis, and provide an overview of treatment and prognosis of this disorder, with specific focus on the management of common symptoms, complications, and patients during pregnancy. Most patients respond well to first-line treatment and surgical resection of tumors. When first-line immunotherapy fails, second-line immunotherapy can often improve outcomes. In addition, treatment with immunomodulators and tumor resection are effective treatment strategies for pregnant patients. Benzodiazepines are the preferred treatment for patients with catatonia, and electroconvulsive therapy (ECT) may be considered when pharmacological treatment is ineffective. Age, antibody titer, cerebellar atrophy, levels of biomarkers such as C-X-C motif chemokine 13 (CXCL13), cell-free mitochondrial (mt)DNA in cerebral serum fluid (CSF), and timing from symptom onset to treatment are the main prognostic factors. Patients without tumors or those who receive insufficient immunotherapy during the first episode are more likely to relapse.

Little Children, Bigger Problems: Anti-N-Methyl D-Aspartate Receptor Encephalitis!

Anti N-methyl D-aspartate receptor (NMDAR) antibody positive autoimmune encephalitis is a well-described entity both in adults as well as in children. The authors report an 18-mo-old boy who presented with seizures, movement disorder, cognitive impairment, and behavioral disturbances. Anti-NMDAR encephalitis was confirmed by detection of NMDAR antibodies in the cerebrospinal fluid. The patient was administered pulse corticosteroids and intravenous immunoglobulin followed by further immunomodulatory therapy. No tumor was detected on screening. The child remained unresponsive to treatment. The authors wish to highlight the occurrence of anti-NMDAR encephalitis in young toddlers and the poor response to therapy often seen in very young children.