Clinical Characteristics of Anti-N-Methyl-d-Aspartate Receptor Encephalitis Overlapping with Demyelinating Diseases: A Review

Anti-N-methyl-d-aspartate receptor encephalitis (NMDARe), a common autoimmune encephalitis, can be accompanied by demyelinating disorders, including multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). To compare the clinical characteristics of patients with different overlapping syndromes, we searched the PubMed database and performed a systematic review. Of the 79 patients with overlapping syndromes, 15 had MS, 18 had aquaporin-4-antibody-positive NMOSD (AQP4-Ab-positive NMOSD), and 46 had MOGAD. Compared with classical NMDARe, overlapping syndromes showed atypical symptoms, such as limb weakness, sensory disturbance, and visual impairments in addition to the main symptoms of NMDARe and a lower ratio of ovarian teratoma. Patients with MOGAD overlap were the youngest, while patients with MS and AQP4-Ab-positive NMOSD overlap tended to be older than patients with classical NMDARe. A majority of patients with NMDARe who overlapped with MS or AQP4-Ab-positive NMOSD were female, but this was not the case for patients overlapped with MOGAD. When NMDARe and demyelinating diseases occurred sequentially, the interval was the longest in patients with NMDARe overlapped with MS. A favorable outcome was observed in patients overlapping with MOGAD, but no robust comparison can be drawn with the patients overlapping with AQP4-Ab-positive NMOSD and MS regarding the small number of available data. The long-term prognosis of overlapping syndromes needs further investigation.

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

Objective

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

Methods

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

Results

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

Conclusion

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

Isolated Memory Loss in Anti-NMDAR Encephalitis

Background and Objectives

To report a case of anti-NMDAR encephalitis presenting with isolated memory dysfunction.

Methods

A 29-year-old woman was admitted to the Neurology Department referring memory impairment with a subacute onset. The initial assessment included EEG, neuropsychological tests, and brain MRI. Serum and CSF samples were collected for immunologic studies. The diagnostic evaluation was completed with a total body PET scan.

Results

Patient's neurologic examination was unremarkable apart from an episodic memory deficit, confirmed by neuropsychological examination. The EEG revealed epileptiform discharges in the temporal lobes, whereas brain MRI showed bilateral temporal lobes hyperintense lesions on fluid-attenuated inversion recovery images and T2-weighted images. NMDAR-IgG was detected in the patient's serum and CSF by cell-based assay confirming the diagnosis of definite anti-NMDAR encephalitis. The total body PET showed only a slight hypometabolism in the right temporal cortex and in the cerebellar hemispheres. After a course of IV immunoglobulin and corticosteroid therapy, a marked improvement of the memory deficit was observed.

Discussion

This case shows that anti-NMDAR encephalitis can present with isolated memory loss. Neural antibody testing in these patients could play a pivotal role in early diagnosis and prompt treatment.

Anti-NMDA receptor encephalitis in older adults: A systematic review of case reports

OBJECTIVE

To ascertain the clinical characteristics of anti-NMDA receptor encephalitis (NMDARE) in older patients.

METHOD

A systematic literature review using PubMed and Scopus of all published case reports of NMDARE was undertaken, from database inception to June 2020. From this, cases reporting on patients older than 65 years of age and whose diagnosis was confirmed by the presence of anti-NMDAR antibodies in CSF were selected.

RESULTS

23 case reports fulfilling the study's criteria were found. Median age was 70.1 years (range 65-84), fourteen were female (60.9%), and mostly presented with acute behavioral and cognitive changes (95.7%). Atypical psychosis occurred in eleven patients (47.8%) with a sudden onset and fluctuating clinical pattern of delusions (39.1%), hallucinations (30.4%), and motility disturbances (34.8%) including catatonia (17.4%). Nine patients presented with seizures (39.1%). Pleocytosis in CSF (>5 WBC) was described in twelve cases (52.2%). Eleven cases (47.8%) had abnormal brain magnetic resonance imaging (MRI) scans with limbic inflammatory lesions. Thirteen patients had an abnormal EEG (56.5%).

CONCLUSION

NMDARE should be included in the differential diagnosis of older patients who present with new psychiatric episodes, especially when characterized by sudden onset psychotic polymorphic symptomatology, fluctuating course with marked cognitive decline, and with catatonic features.

Fatigue in Survivors of Autoimmune Encephalitis

BACKGROUND AND OBJECTIVES

To evaluate the impact of fatigue after autoimmune encephalitis, determine associations with patients' characteristics, and identify factors that contribute to its development.

METHODS

In a first cohort recruited via several encephalitis support organizations, self-reported questionnaires were used to evaluate fatigue, depression, and sleep quality in adults after autoimmune encephalitis. In a second cohort where more in-depth clinical characterization could be performed, adults with encephalitis from 2 tertiary hospitals were evaluated using the same questionnaires. Patients' characteristics were retrospectively captured.

RESULTS

In the first cohort (mean [SD] age; 43 [16] years, 220 [65%] female), 220 of 338 participants (65%) reported fatigue, 175 of 307 (57%) depression, and 211 of 285 (74%) poor sleep quality. In the second cohort (48 [19] years; 43 [50%] women), 42 of 69 participants (61%) reported fatigue, whereas 23 of 68 (34%) reported depression and 44 of 66 (67%) poor sleep quality, despite more than 80% having "good" modified Rankin scale (mRS) scores (0-2). Individuals with anti-NMDA receptor encephalitis reported lower fatigue scores than those with other autoimmune encephalitis types. In a multivariate analysis examining factors at discharge that might predict fatigue scores, only anti-NMDA receptor encephalitis was a (negative) predictor of fatigue and remained so when potential confounders were included.

DISCUSSION

The impact of fatigue after autoimmune encephalitis is prominent and not fully accounted for by depression or sleep quality, nor adequately captured by mRS scores for disability. Fatigue is pervasive across autoimmune encephalitis, although lower scores are reported in anti-NMDA receptor encephalitis. Fatigue should be screened routinely, considered as an outcome measure in clinical trials, and further studied from a mechanistic standpoint.

Real-world experience of assessing antibodies against the N-methyl-D-aspartate receptor (NMDAR-IgG) in psychiatric patients. A retrospective single-centre study

OBJECTIVE

To evaluate the frequency of anti-NMDAR encephalitis in a secondary mental health service and investigate the challenges of its diagnosis in routine clinical practice.

METHODS

Patients whose electronic health records registered an indication for NMDAR-IgG assessment were selected and seropositive patients were reviewed.

RESULTS

In 1661 patients assessed for NMDAR-IgG over 12 years, the positivity rate was 3.79% (95% confidence interval [CI]: 2.87-4.70%). The working diagnosis at assessment was new onset psychosis in 38.7% and a chronic psychotic syndrome in 34.0%. Among seropositive patients, 30 (47.6%, 95%CI: 35.8-59.7%) had a final alternative diagnosis different from encephalitis after a median period of 49 months from onset. Patients with a final diagnosis of encephalitis were more frequently female (27/35 vs 13/30, p = 0.011) than other seropositive patients and had more frequently an acute (34/35 vs 11/30, p < 0.001), fluctuating (21/23 vs 4/27, p < 0.001) or agitated (32/32 vs 10/26, p < 0.001) presentation. Nine encephalitic patients received specialized follow-up for chronic neuropsychiatric problems including learning disabilities, organic personality disorder, anxiety, fatigue, obsessive-compulsive and autism-like disorder.

CONCLUSIONS

In a psychiatric setting, NMDAR-IgG seropositivity rates were low with a positive predictive value for encephalitis around 50% when screened patients had chronic presentations and absence of other diagnostic criteria for encephalitis or psychosis of autoimmune origin. Chronic neuropsychiatric problems in anti-NMDAR encephalitis are not uncommon, so better diagnostic and treatment strategies are still needed.

Clinical Features and Outcomes of Anti-N-Methyl-d-Aspartate Receptor Encephalitis in Infants and Toddlers

OBJECTIVE

We describe the clinical features and outcomes of anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis in infants and toddlers.

METHODS

This was a single-center retrospective study. Infants and toddlers who met the diagnostic criteria for anti-NMDAR encephalitis were recruited for the study. Data on clinical features, treatment, and long-term outcomes were collected retrospectively.

RESULTS

A total of 41 patients (age range: six to 34 months; median age: 23 months; female: 19) were enrolled in this study. Nineteen (46%) patients exhibited classical anti-NMDAR encephalitis, whereas 22 (54%) patients exhibited anti-NMDAR encephalitis after viral encephalitis. There was a high presentation of movement disorders (100%), developmental regression (90%), abnormal behaviors (90%). All patients were administered first-line therapy, with only 17% of them being administered second-line immunotherapy. Two patients succumbed to the disease, whereas none of them relapsed. At the long-term follow-up (more than one year), 20 of 35 (57%) exhibited satisfactory outcomes (modified Rankin Scale ≤2). Compared with patients with classical anti-NMDAR encephalitis (n = 18), patients after viral encephalitis (n = 17) were more likely to have worse clinical outcomes. They exhibited a higher modified Rankin Scale/Pediatric Cerebral Performance Category score and more frequent seizures. A predictor of poor outcome was presentation after viral encephalitis (odds ratio 35.7, 95% confidence interval 4.64 to 275.03, P = 0.001).

CONCLUSION

Anti-NMDAR encephalitis in infants and toddlers clinically presents with movement disorders, developmental regression, and abnormal behaviors. Interestingly, this group had a higher proportion of patients after viral encephalitis, which is regarded as the only risk factor for poor outcomes.

Capgras syndrome and confabulation unfurling anti NMDAR encephalitis with classical papillary thyroid carcinoma: First reported case

Anti NMDA Receptor encephalitis (ANMDARE) is an immune mediated disease of the central nervous system, caused by circulating antibodies against the NMDA receptor present on neuronal surface. It is known to cause a spectrum of disease ranging from mild behavioral and psychiatric manifestations to full blown seizures, dyskinesias and altered sensorium. It can also be paraneoplastic presentation of a hidden tumor, most commonly ovarian teratoma. Here we present a case of ANMDARE with intriguing presentation of Capgras syndrome and confabulations, who was found to have a malignant papillary thyroid carcinoma, which has been rarely reported.

Paroxysmal Sympathetic Hyperactivity in Severe Anti-N-Methyl-d-Aspartate Receptor Encephalitis: A Single Center Retrospective Observational Study

Background

Paroxysmal sympathetic hyperactivity (PSH) is a disorder with excessive sympathetic activity commonly recognized in patients with acquired brain injury. Autonomic instability is frequent in anti-N-methyl-d-aspartate receptor encephalitis (anti-NMDARE). However, PSH in anti-NMDARE has gained little attention.

Methods

We retrospectively reviewed 24 patients diagnosed with severe anti-NMDARE in the neuro-intensive care unit (NICU) between 2014 and 2019. Patients were assessed with the PSH assessment measure (PSH-AM) scale, and categorized into "PSH+" group and "PSH-" group. The clinical characteristics, hospital mortality, and functional outcome by modified Rankin Scale (mRS) score at six months after discharge were compared between the two groups. Among patients with PSH+, the clinical features and pharmacotherapy of PSH were summarized and compared.

Results

Twenty-four patients were included in the study. Twelve of them (50%) were categorized as PSH+ based on PSH-AM scores. There were no significant differences in the demographic characteristic, GCS scores upon admission, incidence of status epilepticus, teratoma occurrence, hospital mortality, and 6-month mRS between PSH+ and PSH- groups. Patients with PSH+ had increased length of NICU stay, hospital stay and duration of mechanical ventilation. The most prominent clinical features of PSH in severe anti-NMDARE were tachycardia and hyperthermia, while posturing was the relatively mildest clinical feature. Propranolol and clonazepam were more commonly used than gabapentin in pharmacotherapy of PSH in severe anti-NMDARE.

Conclusions

The incidence of PSH in severe anti-NMDARE patients was as high as 50%. Patients with PSH demonstrated prolonged NICU stay, hospital stay and increased duration of mechanical ventilation, while no effect on hospital mortality and functional outcome. Clinicians should be aware of the distinctive characteristics and treatment options of PSH in severe anti-NMDARE.

Determinants for Control of Status Epilepticus in Patients with Anti-N-Methyl-D-Aspartate Receptor Encephalitis

BACKGROUND

Treatment guideline for status epilepticus (SE) specifically in patients with anti-N-methyl- D-aspartate receptor (anti-NMDAR) encephalitis is insufficient. This study aimed to clarify the determinants for the control of SE in adult patients with anti-NMDAR encephalitis.

METHODS

Medical records of all patients with anti-NMDAR encephalitis hospitalized between Jan. 2010 and Sep. 2019 were analyzed for the time sequence of seizures and treatments, and antiepileptic drug (AED) regimens related to SE. The outcomes were control of SE and seizures, and the discharge score of modified Rankin Scale (mRS).

RESULTS

All eight patients had seizures and seven (87.5%) suffered from SE which lasted for 3.6 ± 3.9 days. Five patients (71.4%) had SE earlier than using IT, whose SE was controlled by AEDs alone (n = 4) or combined with teratomas resection (n = 1). Another two patients suffered from SE after receiving IT, and one of them had SE only for 1 hour. Moreover, all SE patients received increased types and dosages of AEDs at SE end. A shorter duration of refractory SE was associated with its later occurrence after seizure onset (p = 0.005) and longer duration of AEDs use before SE (p = 0.026). All cases achieved seizure freedom after receiving AEDs and IT.

CONCLUSIONS

In these patients with anti-NMDAR encephalitis, all the SE which occurred before initiating IT was successfully controlled by AEDs alone or combined with teratoma resection, and later onset of refractory SE was associated with a shorter SE duration.

Case of autoimmune polyendocrine syndrome type 3 complicated with anti-N-methyl-D-aspartic acid-receptor encephalitis

Anti-N-methyl-D-aspartate receptor (NMDA-R) encephalitis is an autoimmune disorder in which autoantibodies in the limbic system bind to GluN1 subunits of NMDA-Rs in the brain. We report a rare case of autoimmune polyendocrine syndrome type 3 complicated by anti-NMDA-R encephalitis. After hospitalization for type 1 diabetes, the 39-year-old patient developed various schizophreniform symptoms and seizures after cold-like symptoms. These findings are consistent with the diagnosis of anti-NMDA-R encephalitis. Immune-related encephalitis was suspected at the early phase of the disease, and cerebrospinal fluid was positive for anti-NMDA-R antibody. Early steroid pulse therapy was initiated during the disease course. The condition improved gradually to full recovery. Early detection and treatment of anti-NMDA-R encephalitis should enhance a positive outcome, considering that besides thyroid diseases and type 1 diabetes, various autoimmune diseases are associated with autoimmune polyendocrine syndrome type 3.

[ECT in autoimmune encephalitis]

In this case report, a 27-year-old male presented at a department of neurology with postherpetic anti-N-methyl-d-aspartate (NMDA) receptor autoimmune encephalitis. The patient was psychotic and exhibited symptoms of akinetic and excited catatonia. He was mechanical restrained for a total of 46 days due to violent behaviour. He was treated with olanzapine and lorazepam up to 15 mg/day without effect on catatonic and behavioural symptoms. ECT was initiated, and the patient received a total of 16 treatments. He responded well to the treatment, and the violent behaviour resolved completely after the first treatment. ECT should be considered for catatonia in anti-NMDA-receptor autoimmune encephalitis.

Pediatric anti-N-methyl-d-aspartate receptor encephalitis in southern China: Analysis of 111 cases

OBJECTIVE

To study the clinical features of children diagnosed with anti-NMDAR encephalitis in southern China.

METHODS

Clinical data of children diagnosed with anti-NMDAR encephalitis from October 2014 to June 2020 from one national regional medical center were analyzed. Neurological disability was assessed by modified Rankin Scale (mRS) throughout the course of disease.

RESULTS

111 children (M/F = 49/62; mean onset age = 6.8 y) with anti-NMDAR encephalitis were involved. Prodromal events occurred in 34.2% of patients with infectious events being the most common. Seizure was the most common initial symptom, though movement disorder served as the most common event throughout the course of disease. 9.9% of patients had overlapped with other neuronal autoantibodies. Electroencephalogram showed abnormalities with slow wave (100.0%), epileptic discharge (31.5%) and delta brush (8.1%) respectively. 41.4% of patients had abnormal brain MRI, with focal lesions being the most common. None patients had tumor. 80.9% of patients had good response to first line therapy (steroid plus immunoglobulin), while 14 patients accepted second-line therapy (Rituximab) and all had a good response. Boys were significantly more likely to need more course of steroid. 13.8% of patients relapsed. 2 male patients died. mRS score was significantly improved after treatment. 51.4% of patients had a full recovery and 81.7% had mRS score ≤ 2. The median mRS score of boys after treatment was higher than that of girls. Non-infectious prodromal event, past medical history, perivascular lesions in brain MRI, hospital stay, initial mRS score higher than 3, and RTX treatment were independent risk factors associated with poor prognosis, defined as mRS score > 2.

CONCLUSION

Of pediatric anti-NMDAR encephalitis in southern China: median onset age around 7 years; girls more common; boys might have poor outcome than girls; seizure or movement disorder respectively being most common onset or course symptom; a few overlapped with other neuronal autoantibodies; rare combined with tumor; most had a good response to immunotherapy and a good prognosis; relapse rate relatively high; fatality rate relatively low; some risk factors associated with poor prognosis.

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.

Clinical analysis of a patient simultaneously positive for antibodies of myelin oligodendrocyte glycoprotein and anti-N-methyl-D-aspartate receptor: A case report

RATIONALE

Myelin oligodendrocyte glycoprotein (MOG) antibody (MOG-Ab) disease (MOG-AD) is a type of demyelinating disease of the central nervous system characterized by a high frequency of optic neuritis (ON) attacks. anti-Nmethyl-D-aspartate receptor (NMDAR) encephalitis (anti-NMDARe) is an autoimmune disorder characterized by memory deficits, conscious disturbance, and seizures. Cases of simultaneous occurrence of MOG-Ab and anti-NMDARe antibody (anti-NMDARe-Ab) are rarely reported and could be mistaken for overlapping MOG-antibody disease (MOG-AD) and NMDARe. The diagnosis of such patients is challenging.

PATIENT CONCERNS

We report the case of a 37-year-old man who presented with recurrent headaches for 3 months and worsening symptoms over 2 weeks. He had a history of ON. He had a generalized seizure after 7 days in the hospital.

DIAGNOSIS

Brain magnetic resonance imaging (MRI) and cerebrospinal fluid tests showed no apparent abnormalities. Repeat MRI showed slight lesions 7 days later, and cerebrospinal fluid tests showed the simultaneous occurrence of MOG-Ab and anti-NMDARe-Ab.

INTERVENTIONS

He completely recovered after treatment with low doses of oral corticosteroids.

OUTCOMES

Two months and 2 years follow-up showed that his condition was stable.

LESSONS

The co-occurrence of MOG-Ab and anti-NMDAR-Ab does not indicate the co-occurrence of MOG-AD and anti-NMDARe. Laboratory findings should be combined with the clinical features to achieve an accurate and suitable diagnosis.

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-β, 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.

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.

Bilateral thalamic changes in anti-NMDAR encephalitis presenting with hemichorea and dystonia and acute transient psychotic disorder

Anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis is one of the most common causes of autoimmune encephalitis. Both movement disorders and neuropsychiatric manifestations are considered core features of anti-NMDAR encephalitis. Strong clinical suspicion, along with NMDAR antibody positivity in paired sample of serum and cerebrospinal fluid, with supportive MRI changes clinch diagnosis in majority. We herein report a case of a middle-aged woman with subacute behavioral abnormalities, which were so severe that forced her to attempt suicide. Hemichorea and dystonia, which appeared later in course, are not previously reported movement disorders in combination in anti-NMDAR encephalitis. Further, magnetic resonance imaging showed bilateral thalamic hyperintensities with diffusion restriction, which are in turn not described in this entity. After amalgamation of history, especially the presence of neuropsychiatric symptoms, clinical features, physical examination, and investigations, the diagnosis of anti-NMDAR encephalitis could be established. Our case not only highlights that the combination of hemichorea and dystonia can be features of anti-NMDAR encephalitis, but adds novelty by bilateral symmetric thalamic changes.

An Elderly Case of Paraneoplastic Anti-NMDA Receptor Encephalitis Associated with Small-cell Lung Cancer Expressing NR1 Subunits

A 61-year-old Japanese man presented with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. NR1 antibodies were detected in his cerebrospinal fluid. Chest computed tomography revealed lung tumor. The patient was diagnosed with paraneoplastic anti-NMDAR encephalitis associated with lung cancer and treated with two cycles of intravenous high-dose methylprednisolone and one cycle of intravenous immunoglobulin. However, he died one year later without improvement. An autopsy confirmed small-cell lung cancer (SCLC). Immunohistochemistry revealed the expression of NR1 subunits in the tumor cells, suggesting that SCLC may trigger NR1 autoimmunity though the expression of NR1 subunits as onconeural antigens, expanding the phenotypic spectrum of paraneoplastic neurological syndrome associated with SCLC.

Cryptococcus Meningitis Can Co-occur with Anti-NMDA Receptor Encephalitis

We herein report a 50-year-old man with alcoholic cirrhosis who developed loss of consciousness and tremor of the upper limbs. Magnetic resonance imaging findings were suggestive of limbic encephalitis with bilateral hippocampal damage, and a cerebrospinal fluid (CSF) examination confirmed anti-N-methyl-D-aspartate (NMDA) and anti-glutamate receptor antibodies. Despite initial corticosteroid therapy, meningeal irritation symptoms appeared, owing to the development of cryptococcal meningitis (CM), diagnosed by the detection of cryptococcal capsular polysaccharide antigen in the follow-up CSF analysis. Cerebral infarction with reversible stenosis of major cerebral arteries during the clinical course was also observed. Following administration of antifungals and corticosteroids, the number of cells in the CSF gradually declined, and NMDA receptor antibodies disappeared. Our study demonstrates the unique coexistence of CM with anti-NMDA receptor encephalitis in adults.

Anti-NMDA receptor encephalitis concomitant with myelin oligodendrocyte glycoprotein antibody diseases: A retrospective observational study

Anti-N-methyl-D-aspartate receptor encephalitis (NMDARe) can coexist with myelin oligodendrocyte glycoprotein antibody (MOG-ab) disease.To characterize MOG-ab disease during NMDARe, we analyzed all the patients with MOG-ab disease and NMDARe from our hospital from December 2018 to December 2019 and data from a systematical review of previously published reports. Details of the patients identified were summarized and literature was reviewed.Four of thirty (14.2%) patients with anti-NMDARe had overlapping MOG-ab disease in our department. Analyze together with previously reported cases. Thirty-two NMDARe patients had overlapping MOG-ab disease. The onset age ranged from 3 to 48 years. Twenty-four patients (74%) developed abnormal behavior or cognitive dysfunction during the episodes of anti-NMDARe. None of these patients had tumors. 84% (27/32) patients received high doses of steroids as first-line immunotherapy and 28% (9/32) received mycophenolate mofetil (MMF) to prevent relapse. Twenty-six of twenty-seven (96%) had a good outcome.Steroids are the most common first-line immunotherapies in NMDARe overlapping MOG-ab disease. Most of the NMDARe patients overlapping MOG-ab disease have a good prognosis.

Anti-N-methyl-D-aspartate Receptor Encephalitis: a Rare Complication of Ovarian Teratoma

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is a potentially life-threatening but reversible autoimmune disorder characterized by psychiatric symptoms, cognitive dysfunction, speech dysfunction, seizures, movement disorder, decreased level of consciousness, and autonomic dysfunction or central hypoventilation. It occurs predominantly in young women and approximately half of them have underlying tumors, mainly ovarian teratoma. A 24-year old woman was admitted because of fever, headache, abnormal movement and decreased mental status. Five cycles of plasmapheresis improved her neurological and mental status. Anti-NMDAR antibodies in her CSF and serum were positive, and computed tomography revealed a 1-cm sized mass suggestive of mature cystic teratoma arising from the right ovary. We promptly performed laparoscopic right ovarian cystectomy. She was discharged after 2 weeks with mild memory deficit. Prompt removal of ovarian teratoma and multidisciplinary care are particularly important for good outcome.