Racial and Ethnic Disparities in the Incidence of Anti-NMDA Receptor Encephalitis.

OBJECTIVES: To estimate the incidence of anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis. METHODS: We conducted a retrospective cohort study of >10 million person-years of observation from members of Kaiser Permanente Southern California, 2011-2022. The electronic health record of individuals with text-string mention of NMDA and encephalitis were reviewed to identify persons who met diagnostic criteria for anti-NMDAR encephalitis. Age-standardized and sex-standardized incidences stratified by race and ethnicity were estimated according to the 2020 US Census population. RESULTS: We identified 70 patients who met diagnostic criteria for anti-NMDAR encephalitis. The median age at onset was 23.7 years (IQR = 14.2-31.0 years), and 45 (64%) were female patients. The age-standardized and sex-standardized incidence of anti-NMDAR encephalitis per 1 million person-years was significantly higher in Black (2.94, 95% CI 1.27-4.61), Hispanic (2.17, 95% CI 1.51-2.83), and Asian/Pacific Island persons (2.02, 95% CI 0.77-3.28) compared with White persons (0.40, 95% CI 0.08-0.72). Ovarian teratomas were found in 58.3% of Black female individuals and 10%-28.6% in other groups. DISCUSSION: Anti-NMDA receptor encephalitis disproportionately affected Black, Hispanic, or Asian/Pacific Island persons. Ovarian teratomas were a particularly common trigger in Black female individuals. Future research should seek to identify environmental and biological risk factors that disproportionately affect minoritized individuals residing in the United States.

[Electroencephalogram Features of Anti-N-Methyl-D-Aspartate Receptor Encephalitis and Their Value for Clinical Assessment].

Objective: To analyze the electroencephalogram (EEG) features of anti-N-methyl-D-aspartate receptor encephalitis (anti-NMDARE) and to study the clinical assessment value of the degree of EEG background slowing and the presence of δ brush. Methods: We enrolled 52 patients with anti-NMDARE and collected their clinical data, including age, sex, form of disease onset, status of tumor comorbidity, auxiliary examination findings (cerebrospinal fluid [CSF] anti-methyl-D-aspartate receptor antibody titers, magnetic resonance imaging [MRI] reports, and EEG results), treatment status, and follow-up after discharge. The degree of EEG background abnormality and the presence of δ brush in the EEG of patients with different clinical features were analyzed. Results: Among the 52 patients, 7 (14%) had normal EEG, and 45 (87%), abnormal EEG, including 25 (48%) with mild abnormalities, 11 (21%) with moderate abnormalities, and 9 (17%) with severe abnormalities. δ brush was seen in 6 (12%) patients. At the time of EEG, 32 (62%) patients were in the mild condition group and 20 (38%) patients were in the severe condition group. After 1 year of follow-up, there were 45 (86%) patients in the good prognosis group and 7 (14%) patients in the poor prognosis group. The exacerbation of EEG background abnormalities and the presence of δ brush were indications for an increase in the proportion of patients who were in severe condition, who needed ICU admission, and who had poor prognosis ( P<0.01). The worse the EEG background abnormalities, the higher the proportion of CSF antibody titers>1∶10 ( P=0.035), and the higher the proportion of patients initiating second-line immunotherapy ( P=0.008). The δ brush was seen a higher proportion in patients with comorbid tumors ( P=0.012). The probability of δ brush presence was higher in the first-time diagnosis cases than that in recurrent cases ( P=0.023). Conclusions: The degree of EEG slowing and the presence of δ brush have shown consistent performance in assessing patients' condition and predicting prognosis. The slower the EEG, the more severe the disease, and the worse the prognosis. The presence of δ brush indicates severe disease and poor prognosis. EEG slowing is correlated with the immune status of patients with anti-NMDARE. The slower the EEG, the more severe the immune abnormalities. In clinical practice, patient EEG should be under dynamic monitoring in order to evaluate the effect of immunotherapy. If EEG slowing is not improved, enhanced immunotherapy should be considered as early as possible. The δ brush is seen at a higher proportion in patients with comorbid tumors. Therefore, active efforts should be made to screen for tumors when δ brush is present.

Assessment of cognitive status in pediatric anti-NMDA receptor encephalitis during inpatient rehabilitation: A retrospective cohort.

OBJECTIVES: Anti-NMDA receptor autoimmune encephalitis (NMDARE) is a common pediatric encephalitis, resulting in neuropsychiatric symptoms. Predicting severity and course is challenging, with objective cognitive assessments lacking in NMDARE, especially in children. The CASE (Clinical Assessment Scale in Autoimmune Encephalitis) measures severity in autoimmune encephalitis. The CALS (Cognitive and Linguistic Scale) assesses cognitive-linguistic recovery in children with acquired brain injury. This study examines severity and cognitive status in pediatric NMDARE by comparing objectives measures: modified Rankin score (mRS), CASE, and CALS. METHODS: Twenty-one patients were identified via retrospective chart review with a confirmed NMDARE diagnosis (ages of 3-18 years) who required inpatient rehabilitation. The mRS, CASE, and CALS were assessed at admission and discharge. RESULTS: Scores demonstrated improvement from admission to discharge, with variability in individual recovery trajectories. CALS identified three clusters of patients with differential rates of early recovery. CALS <30 was associated with minimal improvement and poor outcomes. CALS ≥30 had a likelihood ratio score of 12.0 to predict improvement. CASE and CALS were moderately correlated, but neither correlated with mRS. DISCUSSION: CALS and CASE appear to be complementary measures for assessing severity and cognitive status in pediatric NMDARE, including those with low responsiveness, with implications for treatment and outcomes.

Validity and prognostic utility of clinical assessment scale for autoimmune encephalitis (CASE) score in children with autoimmune encephalitis.

INTRODUCTION: The clinical assessment scale for autoimmune encephalitis (CASE) is a recently developed and validated scale to rate the severity of autoimmune encephalitis (AE) in adults. But it is yet to be validated in pediatric AE cases. METHODS: In a prospective observational study, we determined the validity and prognostic utility of CASE in the pediatric population with a diagnosis of probable or definite AE. We also determined clinical, neuroimaging, or laboratory-based prognostic factors for favorable clinical outcomes at 3 months after presentation. We used weighted kappa statistics and the intra-class correlation coefficient of individual item scores and total scores for determining inter-observer and intra-observer reliability respectively. RESULTS: We enrolled a total of 54 patients (28 girls, probable [45%] or definite [55%] AE). Functional status score (FSS), CASE score, and other scores showed significant improvement at the time of discharge and 3-months, as compared to baseline (p < 0.0001). The intra-observer and interobserver reliability of the total scores was excellent (k = 0.94 and 0.95 respectively). CASE was also found to have good internal consistency (Cronbach-α = 0.83). The corrected item-total correlations of all items were >0.40. The correlation between the total CASE score and FSS score at admission, at discharge, and at 3 months was strong (r = 0.90, 0.92, and 0.94, p < 0.001). In multivariate analysis, only seropositivity or definite AE and CASE score at baseline was found to be significant predictive factors for functional status at 3 months (p = 0.03, 0.01). CONCLUSION: CASE score can be used for monitoring the severity of pediatric AE patients. It also has prognostic usefulness for predicting functional independence on follow-up.

Performance of the clinical assessment scale for autoimmune encephalitis in a pediatric autoimmune encephalitis cohort.

Background: The Clinical Assessment Scale for Autoimmune Encephalitis (CASE), a new scale used for rating the severity of autoimmune encephalitis (AE), has demonstrated good validity and reliability in adults with AE, but there is a shortage of data on its performance in children with AE. This study aimed to assess the reliability and validity of the CASE in a cohort of children with AE. Methods: Forty-seven pediatric inpatients with AE who visited Guizhou Provincial People's Hospital between January 1, 2017, and October 31, 2021, were enrolled in the study. The CASE and mRS scores were obtained through a review of detailed medical records from the Health Information System by two pediatric neurologists. Finally, the performance of the CASE in this pediatric AE cohort was analyzed. Results: The results showed that anti-NMDA receptor encephalitis was the most common (61.70%) type of AE in children. The most common clinical manifestations were language problems (85.1%), psychiatric symptoms (80.9%), and dyskinesia/dystonia (78.7%). The CASE had good item reliability and interevaluator reliability; the Cronbach's alpha value of the total score was 0.825, and the intraclass correlation (ICC) was 0.980. The Cronbach's alpha value by item ranged from 0.16 to 0.406; items 1 and 9 had the lowest and highest Cronbach's alpha values, respectively. The criterion validity between CASE and mRS total scores, as quantified by Pearson correlation, was 0.459, indicating slight to good criterion validity. The area under the curve (AUC) was 0.992 (95% confidence interval: 0.974-1.00). A cutoff value of 14 was selected to determine whether a patient needed admission to the ICU; this cutoff had a sensitivity of 100% and a specificity of 92%. The changes in EEG, MRI, and antibody titers were not related to the severity of AE. A CASE score cutoff of 9 was selected to indicate whether second-line treatment would be needed. Conclusion: The CASE has good reliability and validity in children with AE; however, some items of the CASE may not apply to this population. Thus, an in-depth study of the CASE is needed in children with AE.

External Assessment of the Anti-N-Methyl-D-Aspartate Receptor Encephalitis One-Year Functional Status Score in Chinese Pediatric Patients.

Objective: to assess the performance of the Anti-N-Methyl-D-Aspartate Receptor encephalitis (NMDAR) One-Year Functional Status (NEOS) score in predicting one-year functional outcome in Chinese children with anti-NMDAR encephalitis. Methods: children with anti-NMDAR encephalitis at the Children's Hospital of Chongqing Medical University were retrospectively enrolled from January 2014 to December 2020. Patients were categorized into two groups based on the modified Rankin Scale (mRS) at one-year follow-up. Discrimination of the NEOS score was assessed by the area under curve (AUC) of the receiver operating characteristic curve. Calibration of the NEOS score was assessed by comparing predicted probabilities with observed probabilities using a calibration curve and the Hosmer-Lemeshow test. The clinical practicability of the NEOS score was evaluated by performing a decision curve analysis. Results: one hundred seventy-five children (101 females and 74 males) with anti-NMDAR encephalitis and a median age of 7.7 years were enrolled. Of those, 149 (85.1%) had a good outcome at 1 year (mRS ≤ 2), and the remaining 26 (14.9%) had a poor outcome (mRS > 2). Patients with a higher NEOS score had a significantly higher mRS at one-year follow-up [Spearman r = 0.3878, 95% confidence interval (CI): 0.2500-0.5103, P < 0.001]. The AUC of the NEOS score was 0.870 (95% CI: 0.801-0.938, P < 0.001). The observed probability and predicted probability showed moderate consistency in the calibration curve and the Hosmer-Lemeshow test (P = 0.912). The decision curve analysis showed that using the NEOS score to predict one-year outcomes could provide additional net benefit during clinical practice. Conclusions: the NEOS score is a potentially reliable model to predict the one-year functional outcome in Chinese children with anti-NMDAR encephalitis.

Assessment of long-term psychosocial outcomes in anti-NMDA receptor encephalitis.

PURPOSE: The purpose of this study was to assess long-term psychosocial outcomes of anti-N-methyl-d-aspartate (NMDA) receptor encephalitis (anti-NMDARE). METHODS: Adolescents and adults with self-reported anti-NMDARE were invited to complete an online survey distributed by relevant patient organizations. Demographic and clinical information was collected, including the diagnoses initially given for anti-NMDARE symptoms and posthospital care received. Patient-Reported Outcomes Measurement Information System (PROMIS) Psychosocial Impact Illness - Negative short form (Negative PSII) was administered to assess psychosocial outcome of anti-NMDARE. Associations between clinical factors and psychosocial outcomes were evaluated. RESULTS: Sixty-one individuals with anti-NMDARE age 15 years and above participated. Mean age was 33.7 years (standard deviation [SD]: 12.8), and participants were predominantly female (90.2%, n = 55). Mean T-score on PROMIS Negative PSII was 60.7, >1 SD higher (worse psychosocial function) than that of the provided normalized sample enriched for chronic illness (50, SD: 10). Initial misdiagnosis of anti-NMDARE symptoms was associated with decreased odds (odds ratio [OR]: 0.11, p < 0.05), and follow-up with a psychiatrist after hospitalization with increased odds (OR: 8.46, p < 0.05), of return to work/school after illness. Younger age of symptom onset and presence of ongoing neuropsychiatric issues were predictive of worse Negative PSII scores (p < 0.05). CONCLUSION: Individuals with anti-NMDARE demonstrate poor psychosocial outcomes, yet there are no current standards for long-term assessment or management of such symptoms in this population. These findings highlight the need for use of more comprehensive outcome measures that include assessment of psychosocial function and the importance of developing interventions that address this domain for individuals with anti-NMDARE.

Assessment of care transitions and caregiver burden in anti-NMDA receptor encephalitis.

PURPOSE: The purpose of the study was to assess care transitions and caregiver burden among caregivers of individuals with anti-N-methyl-d-aspartate (NMDA) receptor encephalitis (anti-NMDARE). METHODS: Caregivers of individuals with anti-NMDARE were recruited via patient organization websites. Demographic and clinical information as well as responses to the Care Transition Measure 15 (CTM-15) and Zarit Burden Interview (ZBI) were collected. Exploratory factor analysis (EFA) was conducted on the ZBI, and underlying constructs were analyzed for associations with the CTM-15 and clinical characteristics. RESULTS: Seventy-six caregivers participated. On the CTM-15, the top items where caregivers disagreed or strongly disagreed were the following: "when the patient left the hospital, I had a readable and easily understood written plan that described how all of their healthcare needs were going to be met" (73%), "when the patient left the hospital, I was confident that I know how to manage their health" (62%), and "when the patient left the hospital, I had all the information I needed to be able to take care of them" (58%). Worse care transitions significantly predicted higher caregiver burden scores. Mean ZBI score was 44, falling in the moderate to severe burden range. Exploratory factor analysis was conducted and found four common underlying factors associated with total score. Factor 1, the impact of caring on caregivers' personal lives (accounting for 51% of total score variance), was selected for further analysis because of its modifiable nature. Higher ZBI scores were associated with lower CTM-15 scores (p < 0.003) and the individual with anti-NMDARE not returning to driving (p < 0.002). CONCLUSION: This study identified specific elements of care transitions and caregiver burden that are not currently being addressed for individuals with anti-NMDARE. Attention to these aspects of care in the development of targeted interventions may improve outcomes in individuals with anti-NMDARE and their caregivers.

Development of the clinical assessment scale in autoimmune encephalitis.

OBJECTIVE: There is no scale for rating the severity of autoimmune encephalitis (AE). In this study, we aimed to develop a novel scale for rating severity in patients with diverse AE syndromes and to verify the reliability and validity of the developed scale. METHODS: The key items were generated by a panel of experts and selected according to content validity ratios. The developed scale was initially applied to 50 patients with AE (development cohort) to evaluate its acceptability, reproducibility, internal consistency, and construct validity. Then, the scale was applied to another independent cohort (validation cohort, n = 38). RESULTS: A new scale consisting of 9 items (seizure, memory dysfunction, psychiatric symptoms, consciousness, language problems, dyskinesia/dystonia, gait instability and ataxia, brainstem dysfunction, and weakness) was developed. Each item was assigned a value of up to 3 points. The total score could therefore range from 0 to 27. We named the scale the Clinical Assessment Scale in Autoimmune Encephalitis (CASE). The new scale showed excellent interobserver (intraclass correlation coefficient [ICC] = 0.97) and intraobserver (ICC = 0.96) reliability for total scores, was highly correlated with modified Rankin scale (r = 0.86, p < 0.001), and had acceptable internal consistency (Cronbach α = 0.88). Additionally, in the validation cohort, the scale showed high interobserver reliability (ICC = 0.99) and internal consistency (Cronbach α = 0.92). INTERPRETATION: CASE is a novel clinical scale for AE with a high level of clinimetric properties. It would be suitable for application in clinical practice and might help overcome the limitations of current outcome scales for AE. ANN NEUROL 2019;85:352-358.

Neuropsychological assessment as an objective tool to monitor treatment response in anti-N-methyl-D-aspartate receptor encephalitis.

We report a 1-year follow-up of a young woman with anti-N-methyl-D-aspartate receptor encephalitis. Management of autoimmune encephalitis remains challenging as objective and clinically relevant biomarkers are sought, which allow for the monitoring of treatment response. While further investigation is required, we believe that this case highlights the importance of following a comprehensive neuropsychological profile as a clinically relevant biomarker to guide therapeutic decision-making. By relying on the neuropsychological assessment of the patient, treatment with more toxic medications was avoided and her antiepileptic drug regimen was simplified.

Extra-central nervous system target for assessment and treatment in refractory anti-N-methyl-d-aspartate receptor encephalitis.

Anti-N-methyl-d-aspartate-type glutamate receptor autoimmune encephalitis can arise in the setting of ovarian teratoma and often responds to resection. When it occurs in the absence of tumor, failure to respond to treatment may be more likely, and affected patients often require intensive care. To further understand the mechanisms and potential management, we present findings from an autopsy conducted on a young woman who died of refractory autoimmune encephalitis of this type. Rituximab was administered 70 days before death, and both 37 and 14 days before death, CD19+ lymphocytes were only 0.1% of blood cells. Ten sessions of plasmapheresis were performed after rituximab treatment. Nonetheless, the autoantibodies were present in serum 4 days before death, demonstrating ongoing antibody production. The hippocampus and medial temporal lobe demonstrated inflammation with T cell and prominent microglial involvement, but no plasma cells or plasmablasts were found there, or anywhere in the brain, despite an extensive search. Examination of lymph node tissue identified many plasma cells along sinusoids. These findings demonstrate that the antibody-producing cells are long-lived and can reside in lymphoid tissue. Awareness of continuing antibody production, the extra-central nervous system site, the indication for cytotoxic therapy, and the potential for biopsy assessment may lead to more effective treatment.