Cortical atrophy in early-stage patients with anti-NMDA receptor encephalitis: a machine-learning MRI study with various feature extraction.

Conventional brain magnetic resonance imaging (MRI) of anti-N-methyl-D-aspartate-receptor encephalitis (NMDARE) is non-specific, thus showing little differential diagnostic value, especially for MRI-negative patients. To characterize patterns of structural alterations and facilitate the diagnosis of MRI-negative NMDARE patients, we build two support vector machine models (NMDARE versus healthy controls [HC] model and NMDARE versus viral encephalitis [VE] model) based on radiomics features extracted from brain MRI. A total of 109 MRI-negative NMDARE patients in the acute phase, 108 HCs and 84 acute MRI-negative VE cases were included for training. Another 29 NMDARE patients, 28 HCs and 26 VE cases were included for validation. Eighty features discriminated NMDARE patients from HCs, with area under the receiver operating characteristic curve (AUC) of 0.963 in validation set. NMDARE patients presented with significantly lower thickness, area, and volume and higher mean curvature than HCs. Potential atrophy predominately presented in the frontal lobe (cumulative weight = 4.3725, contribution rate of 29.86%), and temporal lobe (cumulative weight = 2.573, contribution rate of 17.57%). The NMDARE versus VE model achieved certain diagnostic power, with AUC of 0.879 in validation set. Our research shows potential atrophy across the entire cerebral cortex in acute NMDARE patients, and MRI machine learning model has a potential to facilitate the diagnosis MRI-negative NMDARE.

MyD88-mediated signaling is critical for the generation of seizure responses and cognitive impairment in a model of anti-N-methyl-D-aspartate receptor encephalitis.

OBJECTIVE: We previously demonstrated that interleukin-1 receptor-mediated immune activation contributes to seizure severity and memory loss in anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. In the present study, we assessed the role of the myeloid differentiation primary response gene 88 (MyD88), an adaptor protein in Toll-like receptor signaling, in the key phenotypic characteristics of anti-NMDAR encephalitis. METHODS: Monoclonal anti-NMDAR antibodies or control antibodies were infused into the lateral ventricle of MyD88 knockout mice (MyD88-/-) and control C56BL/6J mice (wild type [WT]) via osmotic minipumps for 2 weeks. Seizure responses were measured by electroencephalography. Upon completion of the infusion, the motor, anxiety, and memory functions of the mice were assessed. Astrocytic (glial fibrillary acidic protein [GFAP]) and microglial (ionized calcium-binding adaptor molecule 1 [Iba-1]) activation and transcriptional activation for the principal inflammatory mediators involved in seizures were determined using immunohistochemistry and quantitative real-time polymerase chain reaction, respectively. RESULTS: As shown before, 80% of WT mice infused with anti-NMDAR antibodies (n = 10) developed seizures (median = 11, interquartile range [IQR] = 3-25 in 2 weeks). In contrast, only three of 14 MyD88-/- mice (21.4%) had seizures (0, IQR = 0-.25, p = .01). The WT mice treated with antibodies also developed memory loss in the novel object recognition test, whereas such memory deficits were not apparent in MyD88-/- mice treated with anti-NMDAR antibodies (p = .03) or control antibodies (p = .04). Furthermore, in contrast to the WT mice exposed to anti-NMDAR antibodies, the MyD88-/- mice had a significantly lower induction of chemokine (C-C motif) ligand 2 (CCL2) in the hippocampus (p = .0001, Sidak tests). There were no significant changes in the expression of GFAP and Iba-1 in the MyD88-/- mice treated with anti-NMDAR or control antibodies. SIGNIFICANCE: These findings suggest that MyD88-mediated signaling contributes to the seizure and memory phenotype in anti-NMDAR encephalitis and that CCL2 activation may participate in the expression of these features. The removal of MyD88 inflammation may be protective and therapeutically relevant.

Glucocorticoid-dependent multiple sclerosis overlapping anti-NMDA receptor encephalitis: a case report and literature review update.

BACKGROUND: Previous studies suggest a relationship between central nervous system inflammatory demyelinating diseases and anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis. Also, the overlap between anti-NMDAR encephalitis and multiple sclerosis (MS) has been reported. However, the pathogenesis and clinical characteristics are still obscure. CASE PRESENTATION: A 33-year-old woman presented with diplopia and sensory ataxia at the onset. The cerebrospinal fluid (CSF) anti-NMDAR antibodies were positive (1:3.2), and nuclear magnetic resonance imaging (MRI) showed bilateral centrum ovale and lateral ventricle demyelinating lesions. Therefore, she was diagnosed with anti-NMDAR encephalitis. After administering intravenous immunoglobulin and oral prednisone, her lesions disappeared, and symptoms were relieved. The condition was maintained with a low dose of prednisone, but her lesions reappeared on MRI. Consequently, immunomodulatory therapy of mycophenolate mofetil was initiated. However, she developed dysarthria and right limb ataxia after 10 months with a positive CSF anti-NMDAR antibody (1:1) and positive oligoclonal band. The MRI showed symmetrical multiple demyelinating lesions. Considering the MS diagnosis, her neurological dysfunction again improved significantly after intravenous methylprednisolone. Unfortunately, her symptoms aggravated for the second time when teriflunomide was started. Finally, her condition was controlled again with oral prednisone. CONCLUSIONS: Consistent with previous cases of overlapping anti-NMDAR encephalitis and MS, patients often show atypical symptoms on MRIs and immunological tests. The overlap cannot be arbitrarily treated because of the recurrence of previous diseases. Long-term follow-up, dynamic antibody monitoring, and MRI examination are crucial for these patients. The special dependency of the patient on glucocorticoids in this study has been rarely reported, which may guide the treatment of insensitivity to disease-modifying therapy in recurrent overlapping anti-NMDAR encephalitis and MS.

An elderly case of paraneoplastic anti-NMDA receptor encephalitis associated with large cell neuroendocrine carcinoma of the lung.

BACKGROUND: Recent studies have suggested that N-methyl-D-aspartate (NMDA) receptors are involved in the cell proliferation in several tumors. However, there have been no reports demonstrating the expression of NR1 subunit of the NMDA receptor in large cell neuroendocrine carcinoma (LCNEC). CASE PRESENTATION: Here, we report the first elderly case of paraneoplastic anti-NMDA receptor encephalitis associated with LCNEC of the lung with NR1 expression. Of note, NR1 subunit expression in the tumor cells of the present case was confirmed by immunohistochemistry (IHC). Radiation therapy and immunotherapies, such as corticosteroids and intravenous immunoglobulin (IVIG), shrank the tumors and improved neurological symptoms in the present case. Additionally, we also confirmed the expression of NR1 in the tumor cells obtained from three other cases with LCNEC of the lung at our hospital by IHC. CONCLUSION: Our IHC results indicate that LCNEC generally expresses NR1 subunit and NMDA receptor may be involved in the tumor development and growth.

Single-cell RNA sequencing reveals diverse B cell phenotypes in patients with anti-NMDAR encephalitis.

BACKGROUNDS: Anti-N-methyl-D-aspartate receptor encephalitis (NMDAR-E) is a severe autoimmune disorder characterized by prominent psychiatric symptoms. Although the role of NMDAR antibodies in the disease has been extensively studied, the phenotype of B cell subsets is still not fully understood. METHODS: We utilized single-cell RNA sequencing, single-cell B cell receptor sequencing (scBCR-seq), bulk BCR sequencing, flow cytometry, and enzyme-linked immunosorbent assay to analyze samples from both NMDAR-E patients and control individuals. RESULTS: The cerebrospinal fluid (CSF) of NMDAR-E patients showed significantly increased B cell counts, predominantly memory B (Bm) cells. CSF Bm cells in NMDAR-E patients exhibited upregulated expression of differential expression genes (DEGs) associated with immune regulatory function (TNFRSF13B and ITGB1), whereas peripheral B cells upregulated DEGs related to antigen presentation. Additionally, NMDAR-E patients displayed higher levels of IgD- CD27- double negative (DN) cells and DN3 cells in peripheral blood (PB). In vitro, DN1 cell subsets from NMDAR-E patients differentiated into DN2 and DN3 cells, while CD27+ and/or IgD+ B cells (non-DN) differentiated into antibody-secreting cells (ASCs) and DN cells. NR1-IgG antibodies were found in B cell culture supernatants from patients. Differential expression of B cell IGHV genes in CSF and PB of NMDAR-E patients suggests potential antigen class switching. CONCLUSION: B cell subpopulations in the CSF and PB of NMDAR-E patients exhibit distinct compositions and transcriptomic features. In vitro, non-DN cells from NMDAR-E can differentiate into DN cells and ASCs, potentially producing NR1-IgG antibodies. Further research is necessary to investigate the potential contribution of DN cell subpopulations to NR1-IgG antibody production.

Elevated blood and cerebrospinal fluid biomarkers of microglial activation and blood‒brain barrier disruption in anti-NMDA receptor encephalitis.

BACKGROUND: Anti-NMDA receptor (NMDAR) encephalitis is an autoimmune disease characterized by complex neuropsychiatric syndrome and cerebrospinal fluid (CSF) NMDAR antibodies. Triggering receptor expressed on myeloid cells 2 (TREM2) has been reported to be associated with inflammation of the central nervous system (CNS). Matrix metalloproteinase-9 (MMP9) and cluster of differentiation (CD44) were measured to evaluate blood‒brain barrier (BBB) permeability in anti-NMDAR encephalitis. The roles of microglial activation and BBB disruption in anti-NMDAR encephalitis are not well known. FINDINGS: In this work, we detected increased expression levels of CSF sTREM2, CSF and serum CD44, and serum MMP9 in anti-NMDAR encephalitis patients compared with controls. CSF sTREM2 levels were positively related to both CSF CD44 levels (r = 0.702, p < 0.0001) and serum MMP9 levels (r = 0.428, p = 0.021). In addition, CSF sTREM2 levels were related to clinical parameters (modified Rankin Scale scores, r = 0.422, p = 0.023, and Glasgow Coma Scale scores, r = - 0.401, p = 0.031). CONCLUSION: Increased sTREM2 levels in CSF as well as increased CD44 and MMP9 in serum and CSF reflected activation of microglia and disruption of the BBB in anti-NMDAR encephalitis, expanding the understanding of neuroinflammation in this disease. The factors mentioned above may have potential as novel targets for intervention or novel diagnostic biomarkers.

Regional cerebral blood flow in a patient with asystole episodes associated with anti-NMDA receptor encephalitis.

Anti-N-methyl-D-aspartate (NMDA) receptor encephalitis is a rare and severe autoimmune encephalitis that displays neuropsychiatric symptoms and autonomic instability, e.g., hypoventilation and cardiac arrhythmia. Severe arrhythmia including asystole associated with this encephalitis is rare. Several causes have been suggested. Nevertheless, no report of the literature has described examination by functional brain imaging of a patient with asystole during anti-NMDA receptor encephalitis. This case is that of a 34-year-old woman diagnosed as having anti-NMDA receptor encephalitis. She repeatedly showed 10-20 s asystole episodes necessitating a temporary transvenous pacemaker. After resection of the bilateral ovarian cystic tumor, her symptoms improved. Regional cerebral blood flow (rCBF) was evaluated using single-photon emission computed tomography. The rCBF was increased in the amygdala, hypothalamus, anterior cingulate, hippocampus, and anterior temporal lobes, but decreased in the dorsolateral frontal lobes, parietal lobes, and occipital lobes. Findings in this case suggest that altered rCBF in the patient with asystole episodes associated with anti-NMDA receptor encephalitis was observed in several brain lesions. The rCBF increases in the central autonomic networks, i.e., the amygdala, hypothalamus, and anterior cingulate, might be associated with dysregulation of sympathetic and parasympathetic nervous systems leading to asystole.

Relapse factors of patients of anti-N-methyl-D-aspartate receptor encephalitis.

BACKGROUND: The factors associated with anti-N-methyl-D-aspartate (NMDA) receptor encephalitis relapse are yet to be elucidated. AIMS OF THE STUDY: To investigate the factors associated with relapse and prognosis of anti-NMDA receptor encephalitis. METHODS: This retrospective study included patients diagnosed with anti-NMDA receptor encephalitis admitted to the First Affiliated Hospital of Zhengzhou University from January 2013 to October 2019. The clinical features, auxiliary examinations, treatment regimens, and follow-up were recorded. The outcomes were relapse and 2-year disease prognosis. RESULTS: A total of 160 patients were included. Consequently, 6 (5%) deaths, 34 (25.4%) relapses, and 19 (15.2%) patients had a poor prognosis (modified Rankin score (mRS) ≥3) were recorded. The multivariable analyses showed that age (p = .011), abnormal magnetic resonance imaging (MRI) (p = .019), glucocorticoid pulse (p = .009), and intracranial pressure (p = .023) were independently associated with the relapse, while age (p = .030) and central hypoventilation (p = .020) were independently associated with a poor prognosis at 2 years. CONCLUSION: Glucocorticoid pulse therapy reduces the relapse of anti-NMDA receptor encephalitis. Age, abnormal MRI, and intracranial pressure are risk factors for relapse, while age and central hypoventilation are independently associated with poor prognosis.

The prognosis of late-onset anti-N-methyl-D-aspartate receptor encephalitis in China.

OBJECTIVES: Early-onset anti-N-methyl-D-aspartate receptor encephalitis (anti-NMDARE) differs from late-onset anti-NMDARE regarding clinical characteristics. Until recently, research focusing on prognosis of elder adults has been scarce and showed inconsistent results. This study aims to evaluate the prognosis of late-onset anti-NMDARE in China. MATERIALS & METHODS: One hundred and twelve adults diagnosed as anti-NMDARE in four hospitals in China were reviewed retrospectively. Outcome data were assessed using modified Rankin Scale (mRS) score in short term (3 months after discharge) and long term (≥12 months after discharge). The relapse rate was also computed. Multivariable logistic regression was used to evaluate whether there are substantial differences in functional outcomes and recurrence rate across two groups. RESULTS: Of the 112 patients with anti-NMDARE, 81 (72.3%) were early-onset disease and 31 (27.7%) were late-onset disease. Of these, all had short-term follow-up and 70 completed long-term follow-up. Late-onset anti-NMDARE group showed better short-term (OR 2.70, 95% CI 1.09-6.71) and long-term prognoses (OR 10.25, 95% CI 1.90-55.15). Recurrence rates were statistically different between the groups (OR 4.25, 95% CI 1.22-14.75). CONCLUSION: The prognosis for anti-NMDARE in China was poorer for older adults relative to younger adults. The relapse rates were higher in late-onset group compared to early-onset group.

Neuropsychological follow-up of a case of encephalitis by anti-nmda receptor.

Anti-NMDA receptor encephalitis is an autoimmune disease with psychiatric and cognitive symptoms. Our aim is to describe the cognitive follow-up of a patient diagnosed with the disease for 4 years. The results revealed severe cognitive impairment at the initial evaluation. At 3 months, memory and executive function deficits prevailed. At 9 months, only a deficit in verbal memory was found. At 4 years, she presented a mild memory deficit. These results revealed a significant short-term cognitive deficit. Subsequently, executive functions, memory and verbal fluency recovered, while a mild deficit in verbal memory persisted.

Anti-NMDAR encephalitis induced in mice by active immunization with a peptide from the amino-terminal domain of the GluN1 subunit.

BACKGROUND: Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a recently discovered autoimmune syndrome associated with psychosis, dyskinesia, and seizures. However, the underlying mechanisms of this disease remain unclear, in part because of a lack of suitable animal models. METHODS: This study describes a novel female C57BL/6 mouse model of anti-NMDAR encephalitis that was induced by active immunization against NMDARs using an amino terminal domain (ATD) peptide from the GluN1 subunit (GluN1356-385). RESULTS: Twelve weeks after immunization, the immunized mice showed significant memory loss. Furthermore, antibodies from the cerebrospinal fluid of immunized mice decreased the surface NMDAR cluster density in hippocampal neurons which was similar to the effect induced by the anti-NMDAR encephalitis patients' antibodies. Immunization also impaired long-term potentiation at Schaffer collateral-CA1 synapses and reduced NMDAR-induced calcium influx. CONCLUSION: We established a novel anti-NMDAR encephalitis model using active immunization with peptide GluN1356-385 targeting the ATD of GluN1. This novel model may allow further research into the pathogenesis of anti-NMDAR encephalitis and aid in the development of new therapies for this disease.

Seizures and memory impairment induced by patient-derived anti-N-methyl-D-aspartate receptor antibodies in mice are attenuated by anakinra, an interleukin-1 receptor antagonist.

OBJECTIVE: Neuroinflammation associated with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis may facilitate seizures. We previously showed that intraventricular administration of cerebrospinal fluid from patients with anti-NMDAR encephalitis to mice precipitates seizures, thereby confirming that antibodies are directly pathogenic. To determine whether interleukin (IL)-1-mediated inflammation exacerbates autoimmune seizures, we asked whether blocking the effects of IL-1 by anakinra, a selective IL-1 receptor antagonist, blunts antibody-induced seizures. METHODS: We infused C57BL/6 mice intraventricularly with purified serum IgG from patients with anti-NMDAR encephalitis or monoclonal anti-NMDAR IgG; subdural electroencephalogram was continuously recorded. After a 6-day interval, mice received anakinra (25 mg/kg sc, twice daily) or vehicle for 5 days. Following a 4-day washout period, we performed behavioral tests to assess motor function, anxiety, and memory, followed by hippocampus tissue analysis to assess astrocytic (glial fibrillary acidic protein [GFAP]) and microglial (ionized calcium-binding adapter molecule [Iba]-1) activation. RESULTS: Of 31 mice infused with purified patient NMDAR-IgG (n = 17) or monoclonal NMDAR-IgG (n = 14), 81% developed seizures. Median baseline daily seizure count during exposure to antibodies was 3.9; most seizures were electrographic. Median duration of seizures during the baseline was 82.5 s. Anakinra administration attenuated daily seizure frequency by 60% (p = .02). Anakinra reduced seizure duration; however, the effect was delayed and became apparent only after the cessation of treatment (p = .04). Anakinra improved novel object recognition in mice with antibody-induced seizures (p = .03) but did not alter other behaviors. Anakinra reduced the expression of GFAP and Iba-1 in the hippocampus of mice with seizures, indicating decreased astrocytic and microglial activation. SIGNIFICANCE: Our evidence supports a role for IL-1 in the pathogenesis of seizures in anti-NMDAR encephalitis. These data are consistent with therapeutic effects of anakinra in other severe autoimmune and inflammatory seizure syndromes. Targeting inflammation via blocking IL-1 receptor-mediated signaling may be promising for developing novel treatments for refractory autoimmune seizures.

Anti-NMDA receptor encephalitis and overlapping demyelinating disorder in a 20-year old female with borderline personality disorder: proposal of a diagnostic and therapeutic algorithm for autoimmune encephalitis in psychiatric patients "case report".

BACKGROUND: Anti-NMDA receptor encephalitis (NMDAR-E) is an autoimmune encephalitis (AE) mainly affecting young females. It typically presents with isolated psychiatric symptoms (e.g. depressed mood) at first and neurological abnormalities (e.g. seizures, movement disorders) only develop later. Thus, there is a high risk of overlooking NMDAR-E in patients with preexisting psychiatric illness due to symptom overlap in the prodromal period of the disease when treatment is most effective. Although rare, concomitant or sequential development of a demyelinating disorder is increasingly recognized as an associated disease entity (overlap syndrome), with immediate diagnostic and therapeutic implications. CASE PRESENTATION: We report a patient with a borderline personality disorder (BPD), which developed NMDAR-E and an overlapping demyelinating disorder with anti-Myelin oligodendrocyte glycoprotein (MOG) -IgG positivity. The initial clinical presentation with predominantly affective symptoms (e.g. mood lability, anxiety, depressed mood) lead us to suspect an exacerbation of the BPD at first. However, acute changes in premorbid behavior, newly developed psychotic symptoms and memory deficits lead us to the correct diagnosis of an AE, which was further complicated by the development of a demyelinating disorder. As a result of impaired illness awareness and psychosis, diagnostic and treatment was difficult to carry out. The symptoms completely remitted after treatment with methylprednisolone 1 g daily for 5 days and 5 cycles of plasma exchange. CONCLUSIONS: Continuous awareness for neuropsychiatric clinical warning signs in patients with a pre-diagnosed psychiatric disorder is important for a timely diagnosis. Therefore, we believe that the diagnostic and therapeutic algorithm provided here, for the first time specifically addressing patients with preexisting psychiatric illness and integrating overlap syndromes, can be a useful tool. Moreover, in order to timely perform diagnostics and treatment, judicial approval should be obtained rapidly.

Clinical features and management of coexisting anti-N-methyl-D-aspartate receptor encephalitis and myelin oligodendrocyte glycoprotein antibody-associated encephalomyelitis: a case report and review of the literature.

BACKGROUND: Anti-N-methyl-D-aspartate (NMDA) receptor encephalitis is an autoimmune encephalitis caused by antibodies targeting the GluN1 subunit of NMDA receptors. Myelin oligodendrocyte glycoprotein (MOG) antibody disorders are now widely accepted as peculiar neuroimmunological diseases with specific clinical and pathological features. Some rare cases of overlapping anti-NMDA receptor encephalitis and MOG antibody-associated diseases have been reported, presenting complex clinical symptoms that make the disease more difficult to recognize. METHOD: In accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, the terms "NMDAR" and "MOG," "NMDAR" and "demyelination," and "MOG" and "encephalitis" were searched in PubMed. Clinical cases with dual-positive anti-NMDA cerebrospinal fluid receptors and MOG serum antibodies during the disease course were included in this study. RESULTS: A total of 25 patients were analyzed in this study. The age at onset ranged from 3 to 54 years. The median number of relapses was 2.8. Administration of intravenous methylprednisolone and immunoglobulin was the most widely used treatment strategy (19/25 patients). Second-line treatments such as administration of mycophenolate mofetil, rituximab, interferon-ß, azathioprine, cyclophosphamide, and temozolomide were also reported, followed by good outcomes. CONCLUSIONS: The rates of coexisting anti-NMDA receptor encephalitis and MOG antibody-associated encephalomyelitis may be underestimated. Clinical symptoms such as seizures and cognitive decline accompanied by atypical central nervous system demyelination serve as warning signs of possible coexisting anti-NMDA receptor encephalitis and MOG antibody-associated encephalomyelitis. These patients could achieve good outcomes under proper immunotherapies.

HSV encephalitis triggered anti-NMDAR encephalitis: a case report.

BACKGROUND: Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis (AE) is a common cause of nonviral infectious encephalitis, which can be triggered by herpes simplex virus infection. Previous studies have shown that approximately 27% of herpes simplex encephalitis (HSE) patients produce anti-NMDAR antibodies within 3 months. Immunotherapy is recommended in this situation, but some symptoms usually remain in the 1-year follow-up. CASE PRESENTATION: A previously healthy 23-year-old Chinese young woman developed epileptic attack followed by psychiatric symptoms of confusion and irritation as well as cognitive deficits. Brain MRI showed hyperintense lesions of the right temporal lobe on DWI and T2 without contrast enhancement effects. Twenty-one days of acyclovir was administered based on the primary diagnosis of HSE. The anti-NMDAR antibody (IgG) was detected positively on day 11 after disease onset. She had improved cognitive function but suffered another grand mal epilepsy after the first course of intravenous immunoglobulin (IVIG) therapy combined with 1000 mg intravenous methylprednisolone. After discussion, another course of IVIG was started for 5 days. Her symptoms were well controlled with only mild cognitive deficits at the 1-year follow-up (mRS = 1). CONCLUSIONS: Our case indicated that anti-NMDAR antibodies could develop earlier after HSE compared with previous data from adults. We suggested detecting AE antibodies simultaneously with each CSF analysis. Meanwhile, the second course of IVIG therapy was reasonable when symptoms were not controlled after the first course of IVIG combined with IV steroid treatment.

Pharmacologic Treatment and Early Rehabilitation Outcomes in Pediatric Patients With Anti-NMDA Receptor Encephalitis.

OBJECTIVES: To describe the immunotherapy and pharmacologic treatments administered to pediatric patients with N-methyl-D-aspartate receptor encephalitis (NMDARE) during inpatient rehabilitation as well as to examine clinical and demographic variables associated with early functional outcomes. DESIGN: Retrospective chart review and post hoc analysis. SETTING: Pediatric inpatient rehabilitation unit. PARTICIPANTS: Pediatric patients (N=26; mean age, 10.79±5.17y) admitted to an inpatient rehabilitation unit with a confirmed diagnosis of NMDARE. INTERVENTIONS: Inpatient rehabilitation; pharmacologic treatments. MAIN OUTCOME MEASURE: FIM for Children (WeeFIM) Developmental Functional Quotient (DFQ). RESULTS: All patients received first-line immunotherapies to treat NMDARE, and 69% also received second-line immunotherapies. Patients were prescribed an average of 8 medications for symptom management (range, 3-15 per patient), most often for the treatment of agitation (100%), psychiatric symptoms (92%), and seizures (65%). Sixty-five percent of patients demonstrated an improvement in Total WeeFIM DFQ over the course of inpatient rehabilitation, with 35% demonstrating limited to no change in Total WeeFIM DFQ ("unfavorable early outcome"). Those with unfavorable early outcome were significantly younger than those showing more favorable outcome. Pharmacologic treatment for seizures, movement disorders, and decreased arousal or level of consciousness were each associated with unfavorable early outcome independent of age differences. CONCLUSION: Findings highlight the symptomatic heterogeneity and polypharmacy involved in the care and treatment of patients with NMDARE, with patients receiving a variety of immunotherapies and medications for symptom management. The presence of (and treatment for) seizures, movement disorders, and deteriorated neurologic status may each be associated with poor early outcomes in this population. Further investigation is needed to better classify presentations and treatments for this disease and to determine how differences are associated with long-term outcomes.

Ovarian Dermoid Cysts Associated with Paraneoplastic Syndrome N-methyl-D-aspartic Acid Receptor Antibodies Encephalitis.

STUDY OBJECTIVE: To describe the incidence of ovarian dermoid cysts associated with paraneoplastic encephalitis syndrome due to N-methyl-D-aspartic acid (NMDA) receptor antibodies among women undergoing surgical resection of dermoid cysts. DESIGN: Retrospective cohort study. SETTING: University-affiliated department of obstetrics and gynecology. PATIENTS: All patients with pathology-proven ovarian dermoid cysts who underwent surgical resection in our department between January 2008 and December 2019. Their demographic, clinical, and surgical characteristics are described, with emphasis on cases diagnosed with anti-NMDA receptor encephalitis. INTERVENTIONS: Ovarian dermoid cyst resection by cystectomy or salpingo-oophorectomy. MEASUREMENTS AND MAIN RESULTS: A total of 233 patients were operated on for ovarian dermoid cysts, comprising 2 cases diagnosed with anti-NMDA receptor encephalitis (0.85%). Among the women without NMDA receptor encephalitis, the mean age was 33.3 ± 14.9 years, 84.0% were of reproductive age, 5.2% were premenarchal, and 10.8% were menopausal. The mean diameter of the dermoid cyst in this group was 77.3 ± 33.3-mm. The 2 patients diagnosed with anti-NMDA receptor encephalitis were 21 years old and 42 years old. The diameters of their dermoid cysts were 15-mm and 80-mm, respectively. The patients with anti-NMDA receptor encephalitis were managed with laparoscopic resection, plasmapheresis, intravenous immunoglobulins, and corticosteroids; 1 patient also received immunosuppressive treatment. Both recovered without significant neurologic sequela. CONCLUSION: Paraneoplastic syndrome due to NMDA receptor antibodies is a rare complication of dermoid cysts. This complication may occur in younger or older women, as well as in small- or large-diameter cysts. Thus, a high index of suspicion is required to correctly diagnose and treat women presenting with neurologic symptoms in the presence of dermoid cysts.

Pediatric anti-NMDA receptor encephalitis associated with COVID-19.

Anti-N-methyl-D-aspartate receptor encephalitis is a clinical condition characterized by acute behavioral and mood changes, abnormal movements, autonomic instability, seizures, and encephalopathy. We describe a 7-year-old boy diagnosed with autoimmune encephalitis due to NMDAR antibody in association with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (coronavirus disease 2019) (COVID-19), without pulmonary involvement or fever. The patient presented with acute ataxia, rapidly developed encephalopathy, and autoimmune encephalitis was suspected. Steroid treatment was withheld because of lymphopenia and intravenous immunoglobulin was started. The absence of clinical response prompted plasmapheresis and, when lymphocyte counts improved, pulse steroid treatment was applied. The latter was followed by significant improvement and the patient was discharged in a conscious and ambulatory state. Autoimmune encephalitis should be considered in the presence of neurological symptoms accompanying SARS-CoV-2 infection and steroid treatment should be preferred unless limited by contraindications.

Anesthesia for pediatric patients with anti-NMDA receptor encephalitis: A retrospective case series.

INTRODUCTION: Anti-N-methyl-D-aspartate receptor encephalitis is caused by auto-antibodies that target the N-methyl-D-aspartate receptor. Autonomic instability is a hallmark of the disease. The objective of this case series is to examine how anesthesia affects pediatric patients with this disease. METHODS: We performed a retrospective chart review of 28 records in 17 patients who underwent anesthesia. Our primary outcomes were hemodynamic changes during the perioperative period. Heart rate, systolic and diastolic blood pressures, respiratory rate, and oxygen saturation comprise our endpoints. A subgroup of patients, who underwent imaging with anesthesia, was then compared to controls. RESULTS: In anti-N-methyl-D-aspartate receptor encephalitis cases, there were significant percent changes from baseline in heart rate; median = -14.3%, 95% CI (-19.3, -9.0), p < .01 at 30 min and -15.7%, (-21.1, -9.8), p < .01 at 60 min; in systolic blood pressure, -19.4%, (-23.7, -14.8) at 30 min, p < .01, and -14.8%, (-19.7, -9.5) at 60 min, p < .01; in diastolic blood pressure, -41.9%, (-46.9, -36.3), p < .01 at 30 min, and -37.5%, (-43.4, -30.9), p < .01 at 60 min. When compared to controls, there were no significant differences between the two groups across time of anesthesia (baseline to 60 min) in heart rate (p = .24), systolic blood pressure (p = .30), and diastolic blood pressure (p = .11). No patients experienced hemodynamic lability under anesthesia. One patient, with severe symptoms, died within 24 h of anesthesia. CONCLUSION: Although pediatric patients with anti-N-methyl-D-aspartate receptor encephalitis experienced vital sign changes with anesthesia, they were not clinically significant and they behaved similarly to controls. Disease severity may be a risk factor for perioperative complications.

Primary HIV infection presenting with Kaposi sarcoma and limbic encephalitis.

The development of anti-N-methyl-D-aspartate (NMDA) receptor encephalitis is often associated with neoplasia or infectious diseases as antibodies against neurons or synaptic proteins surface. A 30-year-old male patient was admitted to our department because of neurocognitive symptoms, particularly memory difficulties which had appeared a year prior and since then had been increasing. He had a medical history of smoking and hypertension. On examination, there were no focal neurological deficits. However, neuropsychological tests confirmed a lack of concentration and short-term memory impairment. Brain magnetic resonance imaging (MRI) and electroencephalography (EEG) remained unremarkable. Cerebrospinal fluid (CSF) analysis revealed a low lymphocytic pleocytosis without oligoclonal bands. Serum testing for human immunodeficiency virus (HIV) was positive with 420,000 HIV-1-RNA copies/ml. On a more detailed physical examination, a large number of purple patches were found on the entire body, which a biopsy confirmed to be Kaposi sarcoma (KS). A positive serum and CSF NMDA receptor antibody titer (serum 1:280; CSF 1:8) confirmed the diagnosis of an AIDS-associated anti-NMDA receptor encephalitis; therefore, we treated him with antiretroviral and immunosuppressive therapy. After 12 months, the KS lesions faded and the cognitive deficits improved slightly. Our case highlights that a detailed clinical examination and searching for neoplasia and/or an infection are helpful, though often neglected, tools for detecting an anti-NMDA receptor encephalitis.