Pediatric anti-N-methyl-D-aspartate (NMDA) receptor encephalitis: experience of a tertiary care teaching center from north India

A video-based discussion of movement disorders in paediatric anti NMDAR encephalitis: A case series from Eastern India

PURPOSE

The spectrum of movement disorders associated with anti N-Methyl-d-Aspartate-Receptor (NMDAR) encephalitis is myriad, particularly in children, possibilities of which were investigated from two tertiary care centres.

METHODS

A retrospective study was conducted in two tertiary referral centres in Eastern India, analysing data of 8 paediatric patients diagnosed as anti NMDAR encephalitis, presenting with one or more movement disorders (MDs).

RESULTS

All the patients were of Bengali ethnicity with a median age of 9 years (3-16 years) and with female predilection (62.5%). CSF pleocytosis was a common feature in all. Seizures were described in 62.5%% of patients with a solitary patient exhibiting abnormalities on brain imaging. 3 out of 8 (37.5%) of patients presented with a single MD while the remaining had more than one type. Oro-linguo-facial dyskinesias and dystonia (37.5% each) were the most common movement type followed by chorea (12.5%). Complex stereotypies, myoclonus and facial tics were noted in one patient each. All patients received pulse methyl prednisolone. Escalation to second line therapy in form of rituximab was done for 5 patients (62.5%). Following immunotherapy, hyperkinetic movements resolved in 50% of patients, with persistence of movements in one (12.5%). A mortality of 37.5% was noted. Median duration of follow up was 26 months, during which none of the patients had evidence of systemic neoplasm.

CONCLUSION

MDs are a core feature of anti NMDAR encephalitis, particularly in the paediatric age group, understanding and characterization of which, is the key to early diagnosis and effective therapy.

Anti-N-Methyl-D-Aspartate Receptor (NMDAR) Encephalitis in Children and Adolescents: A Systematic Review and Quantitative Analysis of Reported Cases

OBJECTIVE

This pooled analysis, from a systematic review, examines anti-N-Methyl D-Aspartate Receptor (NMDAR) encephalitis presentation in children and adolescents.

METHOD

A comprehensive literature search from database inception through December 31, 2019, using PubMed, PsycInfo, and OVID was performed. Case reports and case series were included. Sample characteristics are described. Prodromal and presenting symptoms between partial recovery and full recovery are compared. The association between presenting symptoms and abnormal MRI, abnormal EEG, and tumor presence are determined.

RESULTS

The sample (n=283) had a mean age of 10.8 years with 75.3% females. The most common prodromal and presenting symptom was seizure (29.7% and 63.3%, respectively). Partial and full recovery did not differ for prodromal and presenting symptoms. Multivariate logistic regression analysis found that (1) delusion were significantly associated with higher odds and aggressive behavior was associated with lower odds for abnormal findings on magnetic resonance imaging (MRI); (2) waxing and waning of symptoms were significantly associated with higher odds for abnormal electroencephalograms (EEG), and (3) increased age and psychosis were each significantly associated with increased odds, and sleep disturbance and orofacial dyskinesia with lower odds for tumor presence.

CONCLUSION

Given the pattern of findings, routinely obtaining MRI and EEG should be considered for anti-NMDAR encephalitis in children and adolescents presenting with delusion and waxing and waning of symptoms, respectively. Investigation of tumors should be considered in patients with anti-NMDAR encephalitis especially when psychosis is present.

Anti-N-Methyl-D-Aspartate Receptor Encephalitis: A Review of Psychiatric Phenotypes and Management Considerations: A Report of the American Neuropsychiatric Association Committee on Research

OBJECTIVE

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is an autoimmune disorder characterized by prominent neuropsychiatric symptoms. Given the nature of its pathophysiology, psychiatrists tend to be one of the first clinicians encountering patients with the disease.

METHODS

In the present review of patients described in the literature with psychiatric symptoms, the authors aimed to characterize the psychiatric symptoms of the disease and its management in adults and adolescents as well as children (≤12 years old). A total of 544 patients fulfilled the inclusion criteria.

RESULTS

The authors found that 77% of patients with NMDAR encephalitis presented initially with psychiatric symptoms. These were mostly agitation (59%) and psychotic symptoms (in 54%, especially disorganized behavior and visual-auditory hallucinations), with agitation even more commonly being the presenting symptom in children (66%). Where psychotic symptoms were detailed, visual (64%) and auditory (59%) hallucinations were the most common, as well as persecutory delusions (73%). However, delusions were not clearly characterized in most cases. Catatonia was described in 42% of adult patients and 35% of children. Of the patients with documented exposure to antipsychotics, 33% were suspected to have an adverse drug reaction (notably, neuroleptic malignant syndrome in 22% of the cases).

CONCLUSIONS

On the basis of these findings, it is important to consider anti-NMDAR encephalitis in the differential diagnosis of patients with an acute onset psychosis, especially in association with agitation, catatonia, or adverse response to antipsychotics. Furthermore, it is important to use antipsychotics with caution in patients with suspected or confirmed anti-NMDAR encephalitis.

A review of EEG in anti-NMDA receptor encephalitis

Anti-N-methyl-d-aspartate receptor encephalitis (anti-NMDARE) is common among autoimmune encephalitides (AE) and can present with protean features and nonspecific laboratory and neuroimaging results. Antibody testing is specific, but results are often delayed, and prompt diagnosis and treatment is vital given associated morbidity and mortality. Electroencephalography (EEG) may be a useful tool given ease of performance and short turn-around time for results. As such, we performed a systematic review of the literature on anti-NMDARE and EEG characteristics. We found that EEG is often pathologic in anti-NMDAR encephalitis, though at times nonspecific. A stronger focus on common EEG features in patient with this type of encephalitis and an effort to identify when these features are present in the course of the disease may allow for improved diagnosis, description and differentiation of anti-NMDARE.

Late-onset anti-N-methyl-d-aspartate receptor encephalitis in China

PURPOSE

This study aimed to summarize the clinical characteristics and outcome of late-onset anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis in China.

METHOD

All cases of people with a definitive diagnosis of anti-NMDAR encephalitis in West China Hospital between June 2012 and April 2017 were retrospectively reviewed. The demographics, clinical characteristics, and outcome of those patients (age≥45years old) were summarized. Comparisons were conducted between older (≥45years old) and younger (18-44years old) adults.

RESULT

Eighteen (12%) of 151 people were ≥45years old, 9 of whom (50%) were female. Psychiatric symptoms were the most common clinical manifestations of older adults and presented in all individuals. At the last follow-up, 14 (78%) of them had a good outcome (modified Rankin Scale: 0-2) and one (6%) died. Compared with 121 younger adults, older adults had a higher proportion of presenting memory deficit as the initial symptom (17% vs. 2%, p=0.023), longer interval from onset to admission (30 vs. 13days, p=0.013), and longer interval from onset to diagnosis (42.5 vs. 24days, p=0.045). No older adults' condition was accompanied with teratoma compared with 75% of younger adults with tumor (p=0.032). And older adults had a tendency to have a lower rate of positive NMDAR antibody (Ab) in serum (28% vs. 52%, p=0.053).

CONCLUSION

Delayed admission and diagnosis are more common in older adults than in younger adults. A comprehensive consideration of all symptoms and early screening of NMDAR Ab, especially in cerebrospinal fluid, is necessary and beneficial to differential diagnosis.

Anti-N-methyl-d-aspartate receptor encephalitis in children: Incidence and experience in Hong Kong

AIM

The study aims to analyze the incidence, clinical features, investigation findings and treatment outcomes of anti-N-methyl-d-aspartate receptor encephalitis in children from Hong Kong.

METHOD

A retrospective study was carried out on paediatric patients diagnosed with anti-NMDAR encephalitis in Hong Kong from January 2009 to December 2015.

RESULTS

Fifteen patients (67% female, 93% Chinese) were identified over seven years and the estimated incidence in Hong Kong was 2.2/million children per year (95% CI 1.2-3.6). The median age of presentation was 12 years (range 1-17 years). The most common symptom groups observed were abnormal psychiatric behavior or cognitive dysfunction (14/15, 93%) and seizures (14/15, 93%), followed by speech dysfunction (13/15, 87%), movement disorders (12/15, 80%), decreased level of consciousness (10/15, 67%) and autonomic dysfunction or central hypoventilation (5/15, 33%). The median number of symptom groups developed in each patient was 5 (range 3-6). All patients were treated with intravenous immunoglobulin and/or steroids. Three patients (20%) with more severe presentation required additional plasmapheresis and rituximab. Outcome was assessable in 14 patients. Among those eleven patients who had only received intravenous immunoglobulin and/or steroids, nine patients (82%) achieved full recovery. One patient (9%) had residual behavioral problem, while another one (9%) who developed anti-NMDAR encephalitis after herpes simplex virus encephalitis was complicated with dyskinetic cerebral palsy and epilepsy. Among those three patients who required plasmapheresis and rituximab, one (33%) had full recovery and two (66%) had substantial recovery. The median duration of follow up was 20.5 months (range 3-84 months).

CONCLUSION

Anti-NMDAR encephalitis is an acquired, severe, but potentially treatable disorder. Ethnicity may play a role in the incidence of anti-NMDAR encephalitis and we have provided a local incidence with the majority of patients being Chinese. The diagnosis of anti-NMDAR encephalitis should be considered in children presenting with a constellation of symptoms including psychiatric and neurological manifestations. Patients may respond to first line immunotherapy. For those who do not, second line therapy is indicated in order to achieve a better outcome.

Epidemiological Profile of Acute Viral Encephalitis

OBJECTIVE

To study the etiology and clinico-epidemiological profile of acute viral encephalitis in children with acute encephalitis syndrome (AES).

METHODS

An observational study including 100 patients fulfilling the criteria for AES was conducted in children of age group 1 mo - 16 y. Viral isolation was done on RD cells, HEp-2 cells and Vero cells from the cerebrospinal fluid samples of suspected viral encephalitis (VE) cases. An enzyme immunoassay for IgM antibodies was performed for measles, mumps, Varicella zoster virus (VZV), Herpes simplex virus 1 (HSV1) and Japanese encephalitis virus (JEV). Multiplex polymerase chain reaction (PCR) was done for Cytomegalovirus, Epstein Barr virus (EBV), HSV1 & 2, VZV, Enterovirus, Parecho virus, Human Herpes virus (HHV 6, 7) and Parvovirus B19. A micro neutralization test was performed for Enterovirus 71.

RESULTS

Out of enrolled 100 patients, 73 were of probable viral encephalitis. HSV1 (31.50%) was the commonest virus followed by Adenovirus (10.95%), Parvovirus (2.73%), JE virus (1.36%), Enterovirus (1.36%), EBV (1.36%), and mixed infection with HSV & EBV (1.36%). HSV 1 caused significant morbidity in children. The common computed tomography (CT) findings were hypodensities in the fronto- parietal lobe followed by cerebral edema.

CONCLUSIONS

The landscape of AES in India has changed in the previous decade, and both outbreak investigations and surveillance studies have increasingly reported non-JEV etiologies; because of these findings there is a need to explore additional strategies to prevent AES beyond vector control and JEV vaccination.

N-Methyl-D-Aspartate Encephalitis our Experience with Diagnostic Dilemmas, Clinical Features, and Outcome

Introduction

A neuropsychiatric syndrome characterized by a wide spectrum of clinical manifestations. It is seen in patients with antibodies against NR1-NR2 heteromers of the NMDA receptor. As the spectrum is mainly psychiatric most patients are treated as psychiatric disease resulting in huge diagnostic delay.

Patient and methods

Here we describe 29 patients with NMDA encephalitis seen by the authors in the last five years. Percentage of Transfected cells showing granular cytoplasmic florescence was considered for positivity and severity both in CSF and serum. Their presenting diagnosis, clinical features and the dilemmas, alarming gaps, laboratory data, response to treatment and relapses are discussed.

Observations

All patients presented with a spectrum of psychiatric symptoms varying from panic to severe aggression, seizures, chorea, hemiplegia, catatonia, mitgehen, mutism, delirium, mania and memory problems. EEG is invariably abnormal as against imaging.

Conclusion

NMDA receptor mediated encephalitis should be suspected in all children and females of adolescent age with refractory neuropsychiatric syndrome. Both CSF and serum should be tested and regular follow up for relapses and neoplasms is mandatory.

Dilemmas and Challenges in Treating Seronegative Autoimmune Encephalitis in Indian Children

Objective:

The main objective is to assess the challenges in diagnosis and treatment while managing seronegative cases of autoimmune encephalitis (AIE) in Indian children.

Methods:

A cohort study of patients with AIE was done where clinical presentations, investigations, management were analyzed and these patients were followed up to assess the evolution of the disease.

Results:

Nine patients were included in the study. Four patients presented with super-refractory status epilepticus (SRSE). Other presentations were behavioral change, hemiplegia, and autonomic dysfunction. Initial magnetic resonance imaging brain was suggestive of AIE in two patients. Only two were seropositive for cerebrospinal fluid (CSF) autoimmune panel. Five patients responded to the first-line immunotherapy and four required the second-line immunotherapy.

Conclusion:

The possibility of autoimmune encephalitis should be considered in patients with super-refractory status epilepticus. A large proportion of children with suspected AE may be “seronegative.” A trial of immunotherapy should be given to these children when there is a strong clinical suspicion of autoimmune encephalitis even in the absence of cerebrospinal fluid autoantibodies.

Clinical characteristics, treatments, and outcomes of patients with anti-N-methyl-d-aspartate receptor encephalitis: A systematic review of reported cases

Anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis is a recently recognized autoimmune disorder which is responsive to immunotherapy. However, the outcomes of different immunotherapies have not been defined and there have been few studies that carried out a comparison among them. To provide an overview of the clinical characteristics, treatments, and outcomes of anti-NMDAR encephalitis, we systematically reviewed the literature in the PubMed, Medline, Embase, Cochrane Library, BioMedical Literature Database (CBM), China National Knowledge Infrastructure (CNKI), and Wan-fang databases. Eighty-three studies with a total of 432 patients were included. The median age was 22years. Two hundred ninety-three (68%) patients were female, 87 (21%) of 412 patients had a tumor, including 68 (78%) patients with ovarian teratoma. Pediatric patients had a higher ratio of seizures to psychiatric symptoms as the initial manifestation (p=0.0012), a lower proportion with a tumor (p<0.0001) and CSF pleocytosis (p=0.0163), and a better outcome (p=0.0064) than adults. Patients who died had a higher proportion of CSF pleocytosis than the patients who survived (p=0.0021). There were no significant differences among three first-line immunotherapy used alone (p=0.9172) or among combinations of every two of them (p=0.3059). With regard to the use of corticosteroid and IVIG, there were no significant differences between the outcomes of early combined treatment and sequential treatment (p=0.7277), or between using corticosteroid first and IVIG first (p=0.5422). Our findings suggest that the clinical characteristics and outcomes for pediatric patients were different from adult patients, and no significant differences were found among different immunotherapies.

Pediatric Anti-N-Methyl-d-Aspartate Receptor Encephalitis: A Review with Pooled Analysis and Critical Care Emphasis

PURPOSE

Anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis is being recognized with increasing frequency among children. Given the paucity of evidence to guide the critical care management of these complex patients, we provide a comprehensive review of the literature with pooled analysis of published case reports and case series.

METHODS

We performed a comprehensive literature search using PubMed, Scopus, EMBASE, and Web of Science for relevant published studies. The literature search was conducted using the terms NMDA, anti-NMDA, Anti-N-methyl-d-aspartate, pediatric encephalitis, and anti-NMDAR and included articles published between 2005 and May 1, 2016.

RESULTS

Forty-eight references met inclusion criteria accounting for 373 cases. For first-line treatments, 335 (89.8%) received high-dose corticosteroids, 296 received intravenous immunoglobulin (79.3%), and 116 (31%) received therapeutic plasma exchange. In these, 187 children (50.1%) had a full recovery with only minor deficits, 174 patients (46.7%) had partial recovery with major deficits, and 12 children died. In addition, 14 patients were reported to require mechanical ventilation.

CONCLUSION

Anti-NMDA encephalitis is a formidable disease with great variation in clinical presentation and response to treatment. With early recognition of this second most common cause of pediatric encephalitis, a multidisciplinary approach by physicians may provide earlier access to first- and second-line therapies. Future studies are needed to examine the efficacy of these current therapeutic strategies on long-term morbidity.

Clinical Characteristics and Follow-up of South Indian Children with Autoimmune Encephalopathy

OBJECTIVE

To describe the clinical characteristics of a cohort of south Indian children with probable autoimmune encephalopathy from a tertiary care academic hospital and to compare this data with the existing literature.

METHODS

Patients with encephalopathy plus one or more of neuropsychiatric symptoms, seizures, movement disorder or cognitive dysfunction were identified. Common infectious causes were excluded. Clinical characteristics, investigations, management and outcome were analyzed.

RESULTS

Thirteen patients were included in the study; 12 were females (92.3 %) and mean age was 9.6 y. Most common presentation was behavior change (13 patients) followed by seizures (11 patients). Three patients showed lymphocytic pleocytosis in CSF and one patient had oligoclonal bands. Initial MRI was normal in all patients except in one. Most common EEG abnormality was mild background slowing. Only one child had ovarian tumor. S.NMDA receptor antibody was positive in 10 patients (83 %), and all of them received immunotherapy. Six out of 13 children were followed up for more than 1 y (mean - 21 mo). Recurrence was noted in 4 out of 6 patients (66 %). On last follow-up, good recovery was seen in 2 children (33 %), moderate disability in 3 (50 %) and severe disability in 1 (16 %).

CONCLUSIONS

The clinical characteristics and outcome of one of the largest single center cohort of Indian children with autoimmune encephalopathy is reported. Autoimmune encephalopathy should be considered as a differential diagnosis in the acute and subacute encephalopathies of childhood and treating pediatrician should be aware of this entity.

Plasma exchange in pediatric anti-NMDAR encephalitis: A systematic review

OBJECTIVE

To clarify the most frequent modalities of use of plasma exchange (PE) in pediatric anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis and to establish the most effective association with other immunotherapies.

METHODS

Systematic literature review on PE in pediatric anti-NMDAR encephalitis (2007-2015).

RESULTS

Seventy-one articles were included (mostly retrospective), reporting a total of 242 subjects (73.2%, 93/127 females; median age at onset 12years, range 1-18). Median time to immunotherapy was 21days (range 0-190). In most cases, PE was given with steroids and IVIG (69.5%, 89/128), or steroids only (18%, 23/128); in a minority, it was associated with IVIG only (7%, 9/128), or was the only first-line treatment (5.5%, 7/128). In 54.5% (65/119), PE was the third treatment after steroids and IVIG, in 31.1% (37/119) the second after steroids or IVIG; only in 14.3% (17/119) was it the first treatment. Second-line immunotherapies were administered in 71.9% (100/139). Higher rates of full/substantial recovery at follow-up were observed with immunotherapy given ⩽30days from onset (69.4%, 25/36) compared to later (59.2%, 16/27), and when PE was associated with steroids (66.7%, 70/105) rather than not (46.7%, 7/15). Significant adverse reactions to PE were reported in 6 patients.

CONCLUSION

Our review disclosed a paucity of quality data on PE in pediatric anti-NMDAR encephalitis. PE use in this condition has been increasingly reported, most often with steroids and IVIG. Despite the limited number of patients, our data seem to confirm the trend towards a better outcome when PE was administered early, and when given with steroids.

Childhood Anti-NMDA Receptor Encephalitis

OBJECTIVES

To study the clinical profile, and outcome of children with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis.

METHODS

This is a retrospective case series of children <12 y of age, diagnosed with anti-NMDAR encephalitis at a tertiary care institute during the period, May 2013 through June 2015.

RESULTS

Twenty patients were tested for suspected anti-NMDAR encephalitis over this 2 y period. Of these, six children were positive for anti-NMDAR antibodies. Four of these six children had completed treatment and two are currently receiving immunotherapy. Behavioral changes, psychosis, seizures and oro-lingual-facial dyskinesia were the presenting features. Extreme irritability, insomnia and mutism were noted in all the children. The symptoms were persistent, and the course was progressive over 4-8 wk duration. Neuroimaging and electroencephalography were non-specific. Intravenous pulse methylprednisolone and immunoglobulins were used as first-line therapeutic agents. Only one patient responded to first line immunotherapy; five out of six children required second-line immunotherapy. One patient recovered following rituximab, and two patients showed a good response to cyclophosphamide pulse therapy; two patients are currently under treatment with second line immunotherapeutic agents. Tumor screen was negative in all children.

CONCLUSIONS

Anti-NMDAR encephalitis is rare but a potentially treatable condition. Timely recognition is essential because treatment is entirely different from other viral encephalitis. Aggressive immunotherapy is the key to a favourable outcome.