Encephalitis Patients Research Articles

Cost of Acute and Sequelae Care for Japanese Encephalitis Patients, Bangladesh, 2011-2021.

Japanese encephalitis (JE) is associated with an immense social and economic burden. Published cost-of-illness data come primarily from decades-old studies. To determine the cost of care for patients with acute JE and initial and long-term sequelae from the societal perspective, we recruited patients with laboratory-confirmed JE from the past 10 years of JE surveillance in Bangladesh and categorized them as acute care, initial sequalae, and long-term sequelae patients. Among 157 patients, we categorized 55 as acute, 65 as initial sequelae (53 as both categories), and 90 as long-term sequelae. The average (median) societal cost of an acute JE episode was US $929 ($909), of initial sequelae US $75 ($33), and of long-term sequelae US $47 ($14). Most families perceived the effect of JE on their well-being to be extreme and had sustained debt for JE expenses. Our data about the high cost of JE can be used by decision makers in Bangladesh.

Teratoma pathology and genomics in anti-NMDA receptor encephalitis.

Ovarian teratoma is a common occurrence in patients with anti-NMDA receptor encephalitis (NMDARe), and its removal is crucial for a favorable prognosis. However, the initial pathogenesis of autoimmunity in the encephalitic teratoma remains unclear. In this study, we aimed to investigate the genomic landscape and microscopic findings by comparing NMDARe-associated teratomas and non-encephalitic control teratomas. A prospective consecutive cohort of 84 patients with NMDARe was recruited from January 2014 to April 2020, and among them, patients who received teratoma removal surgery at Seoul National University Hospital were enrolled. We conducted a comparison of whole-exome sequencing data and pathologic findings between NMDARe-associated teratomas and control teratomas. We found 18 NMDARe-associated teratomas from 15 patients and compared them with 17 non-encephalitic control teratomas. Interestingly, the genomic analysis revealed no significant differences in mutations between encephalitic and non-encephalitic teratomas. Pathologic analysis showed no discrepancies in terms of the presence of neuronal tissue and lymphocytic infiltration between the encephalitic teratomas (n = 14) and non-encephalitic teratomas (n = 18). However, rituximab-naïve encephalitic teratomas exhibited a higher frequency of germinal center formation compared to non-encephalitic teratomas (80% vs. 16.7%, P = 0.017). Additionally, rituximab-treated encephalitic teratomas demonstrated a reduced number of CD20+ cells and germinal centers in comparison to rituximab-naïve encephalitic teratomas (P = 0.048 and 0.023, respectively). These results suggest that the initiation of immunopathogenesis in NMDARe-associated teratoma is not primarily attributed to intrinsic tumor mutations, but rather to immune factors present in the encephalitic patient group, ultimately leading to germinal center formation within the teratoma.

Antibody induced seizure susceptibility and impaired cognitive performance in a passive transfer rat model of autoimmune encephalitis.

Autoimmune encephalitis (AE) is a distinct neuro-immunological disorder associated with the production of autoantibodies against neuronal proteins responsible for pharmacoresistant seizures, cognitive decline and behavioral problems. To establish the causal link between leucine-rich glioma inactivated 1 (LGI1) antibody and seizures, we developed an in-vivo antibody-mediated AE rat model in which serum antibodies (IgG) obtained from blood samples of leucine-rich glioma inactivated 1 (LGI1) protein antibody (IgG) positive encephalitis patients were passively transferred into non-epileptic Wistar rats. Serum IgG of N-methyl-d-aspartate receptor (NMDAR) antibody positive patients were used as positive control since the pathogenicity of this antibody has been previously shown in animal models. Total IgG obtained from the pooled sera of NMDAR and LGI1-IgG positive patients with epileptic seizures and healthy subjects was applied chronically every other day for 11 days into the cerebral lateral ventricle. Spontaneous seizure development was followed by electroencephalography. Behavioral tests for memory and locomotor activity were applied before and after the antibody infusions. Then, pentylenetetrazol (PTZ) was administered intraperitoneally to evaluate seizure susceptibility. Immunohistochemistry processed for assessment of hippocampal astrocyte proliferation and expression intensity of target NMDAR and LGI1 antigens. No spontaneous activity was observed during the antibody infusions. PTZ-induced seizure stage was significantly higher in the NMDAR-IgG and LGI1-IgG groups compared to control. Besides, memory deficits were observed in the NMDAR and LGI1-IgG groups. We observed enhanced astrocyte proliferation in NMDAR- and LGI1-IgG groups and reduced hippocampal NMDAR expression in NMDAR-IgG group. These findings suggest that neuronal surface auto-antibody administration induces seizure susceptibility and disturbed cognitive performance in the passive transfer rat model of LGI1 AE, which could be a potential in-vivo model for understanding immune-mediated mechanisms underlying epileptogenesis and highlight the potential targets for immune-mediated seizures in AE patients.

Cerebral glucose hypometabolism and hypoperfusion of cingulate gyrus: an imaging biomarker of autoimmune encephalitis with psychiatric symptoms

BackgroundAbout 60% of autoimmune encephalitis (AE) patients present psychiatric symptoms, but the underlying mechanism remains unknown. This study examined the role of the cingulate cortex in such patients to identify predictive poor psychiatric factors.MethodsIn this study, 49 AE patients and 39 healthy controls were enrolled. AE patients were further divided into two groups based on the presence/absence of psychiatric symptoms. The ratio of the standardized uptake value (SUVR) and relative cerebral blood flow (rCBF) in different regions of the cingulate cortex were calculated through positron emission tomography–computed tomography (PET/CT) and arterial spin labeling (ASL) MRI, and the results were compared among the three groups. In addition, we followed-up on the psychiatric outcomes and identified the risk factors for poor psychiatric prognosis, focusing on the cingulate cortex.ResultsMore than half of the AE patients (27/49) exhibited psychiatric symptoms. Agitation and thought blocking were typical psychiatric phenotypes, except for anti-glutamic acid decarboxylase 65 (GAD65) encephalitis, which mainly presented with catatonia and a depressed mood. AE patients with psychiatric symptoms experienced reduced metabolism and perfusion of the anterior cingulate cortex (ACC), midcingulate cortex (MCC), and posterior cingulate cortex (PCC). The SUVR of ACC can be used as an independent risk factor of poor psychiatric outcomes, which had an area under the ROC curve (AUC) of 0.865.ConclusionImpaired cingulate cortex function in AE may be the potential mechanism of psychiatric symptoms. Hypometabolism of ACC is an independent prognostic factor predicting an unfavorable psychiatric prognosis in AE.

Abstract 14677: Surgical Thymectomy for Autoimmune Encephalitis With CRMP-5 and AMPAR Antibodies Induced by SARS-CoV-2 Infection

Introduction: SARS-CoV-2 has been linked to development of autoimmune diseases. We describe a case of a patient with untreated thymoma who developed 2 cross-reactive autoantibodies between thymus and brain: collapsing response mediator protein-5 (CRMP-5) and alpha-amino-3-hydroxyl-5-methyl-4-isoxazole propionic acid receptor (AMPAR), triggered by SARS-CoV-2, inducing encephalitis and coma. Emergency thymectomy reduced anti-CRMP-5 and anti-AMPAR antibodies and restored patient neurologic function within 3 months. Description of Case: A 31-year-old male with a known history of thymoma with myasthenia gravis presented with a 1-day history of memory loss, hallucinations, ataxia, involuntary movements, and tachypnea. Rapid nasal swab COVID-19 test was positive. Over several hours, the patient became unresponsive, requiring urgent intubation for airway protection. Brain computed tomography and magnetic resonance imaging with gadolinium showed no abnormalities. Cerebrospinal fluid (CSF) analysis revealed leukocytosis with lymphocytic predominance. Four days later, CSF and serum were tested for and demonstrated high levels of CRMP-5 and AMPAR antibodies, consistent with autoimmune encephalitis. Complete robotic thymectomy was performed. Pathologic analysis revealed type B2 thymoma with negative resection margins. Three months after surgical intervention, antibody titers normalized, the patient regained consciousness, and had no neurologic deficits. Discussion: Surgical thymectomy effectively treats autoimmune encephalitis in patients with thymoma and positive CRMP-5 and AMPAR antibodies in the setting of SARS-CoV-2 infection. This rare condition is typically seen in patients with thymoma or small cell lung cancer who experience acute viral infection. Although autoantibodies to CRMP-5 and AMPAR are known to be induced by viral infection, this is the first time it has been reported for SARS-CoV-2. Timely surgical intervention is necessary to reverse obtundation and acute encephalitis by removing the cross reactive epitopes in the thymus gland. Future studies are needed to explore the molecular mechanism of SARS-CoV-2 induced immune dysfunction and autoimmunity involving cross-reactive epitopes in this deadly syndrome.

Effect of previous heterologous flavivirus vaccinations on human antibody responses in tick-borne encephalitis and dengue virus infections.

Arthropod-borne flaviviruses include a number of medically relevant human pathogens such as the mosquito-borne dengue (DEN), Zika, and yellow fever (YF) viruses as well as tick-borne encephalitis virus (TBEV). All flaviviruses are antigenically related and anamnestic responses due to prior immunity can modulate antibody specificities in subsequent infections or vaccinations. In our study, we analyzed the induction of broadly flavivirus cross-reactive antibodies in tick-borne encephalitis (TBE) and DEN patients without or with prior flavivirus exposure through TBE and/or YF vaccination, and determined the contribution of these antibodies to TBE and dengue virus (DENV) neutralization. In addition, we investigated the formation of cross-reactive antibodies in TBE-vaccination breakthroughs (VBTs). A TBEV infection without prior YF or TBE vaccination induced predominantly type-specific antibodies. In contrast, high levels of broadly cross-reactive antibodies were found in samples from TBE patients prevaccinated against YF as well as in DEN patients prevaccinated against TBE and/or YF. While these cross-reactive antibodies did not neutralize TBEV, they were effective in neutralizing DENV. This discrepancy points to structural differences between the two viruses and indicates that broadly cross-reactive epitopes are less accessible in TBEV than in DENV. In TBE VBT infections, type-specific antibodies dominated the antibody response, thus revealing no difference from that of unvaccinated TBE patients. Our results emphasize significant differences in the structural properties of different flaviviruses that have an impact on the induction of broadly cross-reactive antibodies and their functional activities in virus neutralization.

PREVALANCE OF JAPANESE ENCEPHALITIS IN PATIENTS PRESENTING WITH ACUTE ENCEPHALITIS SYNDROME IN A TERITARY CARE HOSPITAL OF NORTH EASTERN STATE - TRIPURA

Introduction: Japanese encephalitis virus (JEV) is an arthropod-borne flavivirus, which has a wide distribution in many countries of Asia, Western Pacific and in northern Australia. Twenty-four countries from South-East Asia, Western Pacific regions are endemic for this disease and more than three billion people are at risks of infection. This study is conducted to observe the clinicodemographic profile and prevalence of Japanese Encephalitis in patients presenting with Acute Encephalitis Syndrome Methods: An observational longitudinal study was carried over a period of 8 months from January 2023 to august 2023 among 80 indoor patients admitted in department of medicine of a tertiary care hospital in North-Eastern state in Tripura. Results: Total of 80 patients were admitted in male and female wards of Department of Medicine who were diagnosed to have Acute Encephalitis Syndrome. Among 80 patients 58(72.5%) were male and 22(27.5%) were female. Out of 80 patients 60(75%) serum samples were taken and 20(25%) CSF samples were taken of which 9(11.25%) patients were tested positive for serum and 5(6.25%) tested for CSF respectively. Mean age group of patients with positive results was 50.80±10.35. Most common presentation was fever(100%) followed by focal neurological deficit(57%), headache and vomitings (30%), coma(8%), convulsions(15%) and meningeal signs(30%). Out of 14 patients who were positive for JE 12(86%) patients were from rural areas and 2(14%) people were from urban areas. Out of 14 patients 10(71%) were male and 4 patients(29%) were female respectively. Conclusion: In this study we found that a considerable number of patients are suffering from Japanese Encephalitis which enhances and enlightens our knowledge to think about the disease and its complications to prevent the increasing mortality rates among the patients and create awareness among them as most of them are from rural areas.

Impaired functional connectivity of the hippocampus in translational murine models of NMDA-receptor antibody associated neuropsychiatric pathology

Decreased hippocampal connectivity and disruption of functional networks are established resting-state functional MRI (rs-fMRI) features that are associated with neuropsychiatric symptom severity in human anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. However, the underlying pathophysiology of NMDAR encephalitis remains poorly understood. Application of patient-derived monoclonal antibodies against the NR1 (GluN1) subunit of the NMDAR now allows for the translational investigation of functional connectivity in experimental murine NMDAR antibody disease models with neurodevelopmental disorders. Using rs-fMRI, we studied functional connectivity alterations in (1) adult C57BL/6 J mice that were intrathecally injected with a recombinant human NR1 antibody over 14 days (n = 10) and in (2) a newly established mouse model with in utero exposure to a human recombinant NR1 antibody (NR1-offspring) at the age of (2a) 8 weeks (n = 15) and (2b) 10 months (n = 14). Adult NR1-antibody injected mice showed impaired functional connectivity within the left hippocampus compared to controls, resembling impaired connectivity patterns observed in human NMDAR encephalitis patients. Similarly, NR1-offspring showed significantly reduced functional connectivity in the hippocampus after 8 weeks, and impaired connectivity in the hippocampus was likewise observed in NR1-offspring at the age of 10 months. We successfully reproduced functional connectivity changes within the hippocampus in different experimental murine systems that were previously observed in human NMDAR encephalitis patients. Translational application of this method within a combined imaging and histopathological framework will allow future experimental studies to identify the underlying biological mechanisms and may eventually facilitate non-invasive monitoring of disease activity and treatment responses in autoimmune encephalitis.

Analysis of the relation between cerebrospinal fluid antibody titers and clinical characteristics in pediatric patients with anti-N-methyl-D-aspartate receptor encephalitis

ObjectiveThis retrospective study aimed to investigate the relationship between cerebrospinal fluid (CSF) antibody titers of N-methyl-d-aspartate receptor (NMDAR), and clinical characteristics in pediatric patients with anti-NMDAR encephalitis. MethodsThe clinical and laboratory characteristics of hospitalized patients with anti-NMDAR encephalitis, stratified by antibody titers in CSF and disease severity, were retrospectively studied. The demographics, clinical characteristics, main accessory examinations, immunotherapy, and prognosis of patients were recorded, and each observed indicator was statistically analyzed. ResultsA total of 103 pediatric anti-NMDAR encephalitis patients were enrolled in the study, including 41 males (39.8%) and 62 females (60.2%) with a mean age of 8.0 ± 4.0 years. The proportion of patients with cognitive dysfunction and the positive pathogen was higher in the high-titer group than in the low-titer group (p = 0.023, p = 0.042). Consciousness disturbance that occurred as an initial symptom or during the course in the severe group was higher than in the non-severe group (p = 0.002, p < 0.001). More patients in the high-titer group received plasma exchange (PE) than in the low-titer group (p = 0.022). The cure rate of patients was higher with PE (65.2%) than with Corticosteroids and (or) intravenous immunoglobulin (58.1%). ConclusionsPatients with symptoms of disturbance of consciousness may be severer. The severity in pediatric anti-NMDAR encephalitis patients was not correlated with anti-NMDAR antibody titers. Patients with high CSF antibody titers had a better prognosis after early PE therapy.

Long term outcomes in patients with anti-DPPX autoimmunity

DDPX antibody-associated encephalitis is characterized by cognitive dysfunction, neuropsychiatric symptoms, and CNS hyperexcitability, preceded by prodromal weight loss and diarrhea. Data regarding long-term outcomes is scarce. We retrospectively identified six anti-DPPX encephalitis patients across all three Mayo Clinic sites with inclusion criteria: 1) positive DPPX cell-based assay and mouse tissue-based immunofluorescence samples in both serum and CSF; 2) duration of follow up of at least 36 months from symptom onset to last follow up. Only one patient had a paraneoplastic process in the setting of chronic lymphocytic leukemia. At last follow up, all patients had resolution of GI symptoms. Residual cognitive impairment was seen in 4/6 (67%). Clinical stability was reached in 3/6 (50%) while on immunotherapy. Immunotherapy was discontinued in 2/6 (33%) and they remained stable without relapse at last follow up. One patient died of unclear etiology. Overall long-term outcomes are good in anti-DPPX encephalitis. Symptoms can improve on immunotherapy, but full resolution and return to premorbid baseline is unlikely.

Typical metabolic pattern of 18F-FDG PET in Anti-NMDAR encephalitis in the acute and subacute phases and its correlation with T2 FLAIR-MRI features

Background/aimsEarly diagnosis of Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis with non-invasive imaging modalities benefiting is crucial to guarantee prompt treatments decision-making and good prognosis for patients. The present study aimed to explore the correlation of MRI features with brain metabolism characteristics of 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) and to describe the metabolic patterns in Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis at acute and subacute phases. Twenty-four patients with anti-NMDAR encephalitis confirmed by serum and/or CSF tests at acute and subacute phases, 9 females and 15 males, with an age range of 6–80 years, were enrolled in this retrospective study as encephalitis group. 18F-FDG PET and MRI findings of all patients were investigated and interpreted with visual analysis. Chi-square test was performed to compare the diagnostic sensitivity between MRI and PET. Independent sample t-test was used to compare the standardized uptake value ratio (SUVR) of each ROI between the encephalitis group and control group, which consisted of 24 healthy volunteers of the same age and gender.ResultsThere was no statistical difference in the diagnostic sensitivity between FDG PET (23/24, 95.83%) and MRI (18/24, 75.00%) in anti-NMDAR encephalitis patients (P > 0.05). Three categories of abnormalities shown on T2 FLAIR, including shallow of sulci and swelling of brain tissue, increased signal in the sulci, increased signal on brain gray matter or adjacent white matter presented hypermetabolism on PET, excepting increased signal in brain linear structure with hypometabolism of the basal ganglia on PET. We identified 19 brain regions with hypermetabolism and 16 brain regions with hypometabolism that exhibited statistically significant changes in SUVRs between anti-NMDAR encephalitis group and control group (FDR P < 0.05).ConclusionAnteroposterior glucose metabolism gradient (frontal-temporal/parietal-occipital) is proved to be a typical pattern of anti-NMDAR encephalitis at the acute and subacute phases in both visual and statistical testing. Interestingly, the pattern is also commonly found in the anterior and posterior portions of the parietal lobe and cingular cortex, which may be a potential indicator for the diagnosis of this disorder. In addition, MRI is an important and reliable neuroimaging modality to assist in the correct evaluation of activity changes on individual 18F-FDG PET.

Dynamic and static changes of amplitude of low-frequency fluctuations in anti‑N‑methyl‑D‑aspartate receptor encephalitis.

Previous neuroimaging research has examined static local brain activity changes in patients with anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis. However, the dynamic properties of local brain activity in anti-NMDAR encephalitis remain unknown. This study used a combination of the amplitude of low-frequency fluctuation (ALFF) method and a sliding-window dynamic analysis approach to examine the time-varying local brain activity changes in anti-NMDAR encephalitis. Results showed that patients with anti-NMDAR encephalitis exhibited increased dynamic ALFF (dALFF) variability in the left inferior occipital gyrus compared to healthy controls (HCs), while the patients exhibited decreased sALFF in widespread regions, including the left inferior frontal gyrus, left medial frontal gyrus, bilateral putamen, left medial superior frontal gyrus. dALFF had superior classification performance in distinguishing anti-NMDAR encephalitis patients from HCs over sALFF, but sALFF was correlated with multiple clinical and neuropsychological measures. These findings may shed light on anti-NMDAR encephalitis brain dysfunction from the perspective of dynamic local brain activity. sALFF and dALFF analyses provide complementary information, emphasizing the potential usefulness of combining sALFF and dALFF in elucidating the neuropathological mechanisms of autoimmune encephalitis and may ultimately inform future disease diagnosis.

A new adjunct in the differentiation of encephalitis and meningitis after negative cerebrospinal fluid culture: systemic inflammatory immune index

Objectives: Encephalitis and meningitis can have serious and potentially life-threatening consequences. This study aims to investigate whether the effects of systemic immune inflammation index (SII) and neutrophil/lymphocyte (N/L) ratio on differential diagnosis, severity, and clinical outcomes are superior to each other in patients diagnosed with encephalitis and meningitis in the emergency department. Methods: Patients aged 18 years and older who presented to the adult emergency department of the hospital and were diagnosed with meningitis or encephalitis between January and December 2022 were included in the study. Patients under 18 and those with missing data in their files were excluded from the study. N/L ratio, SII values, and other associated parameters were compared between the group with mortality and the group who survived both diseases. Results: There were significant differences in neutrophil, lymphocyte, N/L ratio, SII, and C-reactive protein (CRP) values between meningitis and encephalitis patients. N/L ratio and SII values were significantly lower in encephalitis patients than in meningitis patients. There was no significant difference in any of the parameters between surviving and deceased patients. Conclusions: Simple calculable ratios such as SII and N/L ratio can be a supportive parameter in the differential diagnosis of the disease. However, it has been observed that using these indices is not a useful tool in determining the severity and prognosis of patients with encephalitis and meningitis.

A Prospective Observational Study of Autoimmune Encephalitis in Northwestern India.

Autoimmune encephalitis (AIE) is a group of rare, increasingly recognized, potentially reversible, noninfectious causes of unexplained encephalitis. It affects any age-group and has a plethora of clinical presentations, the most common being the neuropsychiatric manifestation. The diagnosis of this entity at the right time and proper treatment with immunotherapy can save many lives. In this study, we describe the demographic profile, clinical spectrum, diagnosis, and treatment of 42 patients with features of AIE. This is a prospective study where 42 cases were selected from a tertiary care center in Northwestern India. Patients with suspected AIE underwent detailed clinical assessment, routine blood tests, magnetic resonance imaging (MRI) brain, electroencephalography (EEG), cerebrospinal fluid (CSF) study, and autoimmune profile in blood and CSF. Screening for malignancy was done in all patients with computer tomography (CT) thorax and abdomen and tumor markers. Among 42 patients, males, and females were almost equally affected. The mean age of onset was 31 years. Anti-N-methyl-D-aspartate receptor (anti-NMDAR) Encephalitis was the commonest of all AIE (57%) followed by anti-leucine-rich glioma inactivated-1 (anti-LGI-1) related AIE (11.9%), anti-contactin-associated protein 2 (anti-CASPR2) related AIE (4.7%), and steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT) related to antithyroid peroxidase (anti-TPO) antibody (2.3%). Neuropsychiatric manifestation is the commonest. The seizure was noted in around 72% of patients, the commonest in the anti-NMDAR group. Faciobrachial dystonic seizure (FBDS) was noted in all five anti-LG1-1 encephalitis patients. CSF abnormalities were seen in 33.3% of patients in the form of pleocytosis or raised protein, or both. MRI abnormality was seen in 52% of patients. EEG was abnormal in 10% of patients, and delta brush was noted in three anti-NMDAR patients. All patients received immunotherapy in the form of intravenous immunoglobulin (IVIg) or pulse IV methylprednisolone (IVMPS), or both. Two patients nonresponsive to IVIg and IVMPS received rituximab. Almost all patients responded to immunotherapy. Autoimmune encephalitis (AIE), a potentially treatable immune-responsive entity, is a common neurological problem and may be an answer to a large number of cases having unexplained encephalitis. Good clinical acumen and knowledge are required for early diagnosis and treatment of this potentially reversible disorder. How to cite this article: Sharma B, Paul M, Bagaria AK. A Prospective Observational Study of Autoimmune Encephalitis in Northwestern India. J Assoc Physicians India 2023;71(9):39-44.

Abnormal DNA methylation analysis of leucine-rich glioma-inactivated 1 antibody encephalitis reveals novel methylation-driven genes related to prognostic and clinical features

BackgroundAberrant DNA methylation occurs commonly during pathogenesis of neuroimmunological diseases and is of clinical value in various encephalitis subtypes. However, knowledge of the impact of DNA methylation changes on pathogenesis of leucine-rich glioma-inactivated 1 (LGI1) antibody encephalitis remains limited.MethodsA total of 44 cytokines and 10 immune checkpoint moleculars (ICMs) in the serum of patients with LGI1 encephalitis and healthy donors (HDs) were measured to evaluate the association of them with clinical parameters. Genome-wide DNA methylation profiles were performed in peripheral blood mononuclear cell (PBMC) from LGI1 encephalitis patients and HDs using reduced representation bisulfite sequencing (RRBS) and validated for the methylation status by pyrosequencing. MicroRNA profiles were acquired in serum exosome by small RNA sequencing. Targeted cytokines expression was assessed at the presence or absence of miR-2467-5p in PBMCs and the culture media, and the binding of miR-2467-5p and its targeted genes was validated by luciferase assay.ResultsThere existed significant difference in 22 cytokines/chemokines and 6 ICMs between LGI1 encephalitis patients and HDs. Decreased PDCD1 with increased ICAM1 could predict unfavorable prognosis in one-year follow-up for LGI1 encephalitis patients. Fifteen of cytokines/chemokines and ICMs presented DNA-methylated changes in the promoter and gene body using RRBS in which five were verified as methylation status by pyrosequencing, and the methylation level of CSF3, CCL2, and ICAM1 was conversely associated with their expression in PBMCs. By combining RRBS data with exosome-derived microRNA sequencing, we found that hypomethylated-driven hsa-miR-2467-5p presented elevated expression in serum exosomes and PBMCs in LGI1 encephalitis. Mechanically, miR-2467-5p significantly induced reduced expression of CSF3 and PDCD1 by binding with their 3`UTR while enhanced CCL15 expression, but not significantly correlated with peripheral blood CD19 + B cell proportion of LGI1 encephalitis patients.ConclusionsOur results provided convincing evidence for DNA methylation changes, microRNA profiles in serum exosome for LGI1 encephalitis, and we also identified several novel cytokines related to clinical features in which some represented epigenetic modification of methylated-driven pattern and microRNA modulation. Our study contributed to develop treatment for epigenetic pathogenesis in LGI1 encephalitis.

Autoimmune Limbic Encephalitis in Patients with Hematologic Malignancies after Haploidentical Hematopoietic Stem Cell Transplantation with Post-Transplant Cyclophosphamide.

Autoimmune limbic encephalitis (LE) is a rare, but devastating complication of allogeneic hematopoietic stem cell transplantation (HSCT). There is currently limited evidence describing the risk factors, laboratory features, and underlying mechanisms of this neurologic adverse event. We retrospectively reviewed available clinical, imaging, and laboratory data from adult patients with hematological malignancies who underwent haploidentical HSCT with post-transplant cyclophosphamide (PTCy) at Chungnam National University Hospital from June 2016 to May 2020. Patients who developed LE were compared to those who did not based on clinical assessment, serum inflammatory biomarkers, and reconstitution of various T cell populations. Of 35 patients, 4 developed LE. There were no differences in patient demographics, donor demographics, or treatment conditions between patients that did and did not develop LE. Overall, patients with LE had worse clinical outcomes and overall survival than those without. In addition, they tended to have higher markers of systemic inflammation in the early post-transplant period, including fever, C-reactive protein (CRP), and cytokines. Remarkably, baseline interleukin-6 levels before HSCT were found to be higher in patients who developed LE than those who did not. In addition, analysis of T cell subsets showed impaired expansion of CD25+FOXP3+ regulatory T (Treg) cells in LE compared to non-LE patients despite appropriate reconstitution of the total CD4+ T cell population. Patients that developed LE within the first 30 days of HSCT were likely to have high serum IL-6 among other inflammatory cytokines coupled with suppression of regulatory T cell differentiation. Further work is needed on the mechanisms underlying impaired Treg expansion following HSCT and potential therapies.

Gastrodin Improves Quality of Life and Outcome of Autoimmune Encephalitis Treatment with High-Dose Gamma Globulin and Collaborative Care

This study aims to elucidate the effectiveness of gastrodin in improving the outcome of autoimmune encephalitis patients receiving high-dose gamma globulin plus collaborative nursing care. Gastrodin led to higher post-treatment Mini-mental State Examination scores, CD3+, CD4+, IgA, IgG, and IgM than the control group, and lower inflammatory cytokine levels (P &lt; 0.05). To sum up, gastrodin administration to patients receiving high-dose gamma globulin and collaborative nursing care was highly effective in treating autoimmune encephalitis and can effectively improve patients’ quality of life.

Clinical study of autonomic dysfunction in patients with autoimmune encephalitis

BackgroundAutoimmune encephalitis (AE) is a collective name, covering an emerging spectrum of autoimmune-mediated neurological diseases related to antibodies and synaptic or intracellular proteins. Anti-NMDAR, anti-LGI1, and anti-GABABR are three types of neuronal cell surface antibodies. Autonomic dysfunction represents a frequently occurring clinical manifestation. This observational study purposes to investigate comparisons between two groups with or without autonomic dysfunction and detect the autonomic dysfunction and other indexes in anti-NMDAR, anti-LGI1, and anti-GABABR cohorts. MethodsPatients with anti-NMDAR, anti-LGI1 and anti-GABABR encephalitis were recruited from the May 2017 to the April 2022. The following information was recorded: age, age at onset, tumor presence, gender, prodromal symptoms, clinical manifestations, cranial magnetic resonance imaging, cerebrospinal fluid and blood examinations, and immunotherapy. ResultsThere were totally 161 patients enrolled in this study. Among these participants, 104 individuals (64.6%) presented autonomic dysfunction and the remaining 57 (35.4%) were free of autonomic dysfunction. Sinus tachycardia was the most common autonomic dysfunction, followed by pollakiuria/uroclepsia, feverscence, central hypoventilation, sinus bradycardia, constipation, uroschesis, hyperhidrosis, hypersalivation, hypotension, and early satiety/emesis. Compared to patients without autonomic dysfunction, those with autonomic dysfunction had a higher incidence of central hypoventilation and ICU admissions. Meanwhile, in both groups with or without autonomic dysfunction, meatal behavior disorder, cognitive impairment, and epileptic seizure were three most common clinical manifestations. There were no significant differences in cranial magnetic resonance imaging (MRI), cerebrospinal fluid (CSF) examination, antibody titers and number of immunotherapy types. Further analysis of AE mediated by distinct neuronal surface antibodies demonstrated that there were 85 anti-NMDAR, 56 anti-LGI1, and 20 anti-GABABR encephalitis patients. The significant differences between these three cohorts appeared in age, tumor presence, fervescence presence and antibody titers. ConclusionThis study demonstrated the comparisons between autonomic dysfunction group and autonomic dysfunction-free group and provided insights into better diagnosis and treatment.

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

BackgroundAnti-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.FindingsIn 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).ConclusionIncreased 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.

Efficacy of immunotherapy and prognosis in anti-LGI1 encephalitis patients: A meta-analysis.

To assess the efficacy and safety of immunotherapy for LGI1 antibody encephalitis, and consider the predictors of poor outcomes following immunotherapy. We searched PubMed and Embase for articles reporting the immunotherapy data of anti-LGI1 encephalitis patients. The proportions of patients with poor outcomes (modified Rankin Scale [mRS] score > 2) at 3 months, 12 months, and the last follow-up, as well as the odds ratio [OR] of predictors were pooled. The review included 162 articles with 1066 patients. The proportion of patients with poor functional outcomes was 21% at 3 months, 14% at 12 months, and 14% at the last follow-up after receiving immunotherapy. The proportion of patients with reported relapse was 16.6%. The mean duration from onset to the first relapse was 15.6 months. Predictors significantly associated with poor outcomes were age (increase of 1 year), the presence of cognitive impairment, and CSF LGI1 antibody positive. We did not find a statistically significant association between the worst mRS score in the acute phase, the presence of faciobrachial dystonic seizures (FBDS), days from symptom onset to immunotherapy, second-line treatment, maintenance immunotherapy, or follow-up time and outcomes. Although most patients respond to immunotherapy, a minority of patients still have poor outcomes. Advanced age, cognitive impairment, and CSF LGI1 antibody positive are associated with an increased risk of poor outcomes. However, due to the insufficiency of the data, these conclusions need to be interpreted with caution.