Diagnosis Of Autoimmune Encephalitis Research Articles

Suspected autoimmune encephalitis: A retrospective study of patients referred for therapeutic plasma exchange.

Autoimmune encephalitis (AE) comprises a heterogeneous group of autoantibody-mediated disorders targeting the brain parenchyma. Therapeutic plasma exchange (TPE), one of several first-line therapies for AE, is often initiated when AE is suspected, albeit prior to an established diagnosis. We sought to characterize the role of TPE in the treatment of suspected AE. A single-center, retrospective analysis was performed of adults (≥18 years) who underwent at least one TPE procedure for "suspected AE." The following parameters were extracted and evaluated descriptively: clinicopathologic characteristics, treatment course, TPE-related adverse events, outcomes (e.g., modified Rankin scale [mRS]), and diagnosis once investigation was complete. A total of 37 patients (median age 56 years, range 28-77 years, 62.2% male) were evaluated. Autoimmune antibody testing was positive in serum for 43.2% (n = 16) and cerebrospinal fluid for 29.7% (n = 11). Patients underwent a median of five TPE procedures (range 3-16), with 97.3% (n = 36) via a central line and 21.6% (n = 8) requiring at least one unit of plasma as replacement fluid. Fifteen patients (40.5%) experienced at least one TPE-related adverse event. Compared with mRS at admission, the mRS at discharge was improved in 21.6% (n = 8), unchanged in 59.5% (n = 22), or worse in 18.9% (n = 7). Final diagnosis of AE was determined to be definite in 48.6% (n = 18), probable in 8.1% (n = 3) and possible in 27.0% (n = 10). Six (16.2%) patients were ultimately determined to have an alternate etiology. Empiric TPE for suspected AE is generally well-tolerated. However, its efficacy remains uncertain in the absence of controlled trials, particularly in the setting of seronegative disease.

A case of NMDAR Encephalitis with muscular pain as the main presentation

BackgroundPersistent somatoform pain disorder (PSPD) is often the initial diagnosis in patients seeking treatment in psychiatric departments, making it challenging to consider organic nervous system diseases. However, autoimmune encephalitis can present with atypical initial symptoms, leading to misdiagnosis or missed diagnosis. Lumbar puncture, with antibody support, plays a crucial role in diagnosing autoimmune encephalitis.Case presentationThis report describes a 40-year-old male adult patient who was initially diagnosed with persistent somatoform pain disorder in 2022. The patient reported a reduction in pain while resting on his back. There were no fever or relevant medical history. Despite 8 months of symptomatic treatment, the symptoms did not improve. Moreover, the patient developed confusion, gibberish speech, non-cooperation during questioning, and increased frequency and amplitude of upper limb convulsions. Lumbar puncture revealed elevated protein levels and protein-cell dissociation. The autoimmune encephalitis antibody NMDAR (+) was detected, leading to a diagnosis of autoimmune encephalitis (NMDAR).ConclusionAutoimmune encephalitis (NMDAR), starting with persistent somatoform pain (PSPD), often presents with atypical symptoms and can be easily misdiagnosed. Therefore, it is important to consider the possibility of organic nervous system disease in time, and to test serum or cerebrospinal fluid antibodies to rule out organic nervous system disease after symptomatic treatment of mental disorders is ineffective. This approach facilitates the early diagnosis of autoimmune encephalitis and other underlying organic neurological disorders.

Interest of rare autoantibodies in autoimmune encephalitis and paraneoplastic neurological syndromes: the utility (or futility) of rare antibody discovery.

The increasing recognition and diagnosis of autoimmune encephalitis (AE) and paraneoplastic neurological syndromes (PNS) is partly due to neural autoantibody testing and discovery. The past two decades witnessed an exponential growth in the number of identified neural antibodies. This review aims to summarize recent rare antibody discoveries in the context of central nervous system (CNS) autoimmunity and evaluate the ongoing debate about their utility. In the last 5 years alone 15 novel neural autoantibody specificities were identified. These include rare neural antibody biomarkers of autoimmune encephalitis, cerebellar ataxia or other movement disorders, including multifocal presentations. Although the clinical applications of these rare antibody discoveries may be limited by the low number of positive cases, they still provide important diagnostic, prognostic, and therapeutic insights.

Magnetic Resonance Imaging Characteristics of LGI1-Antibody and CASPR2-Antibody Encephalitis

Rapid and accurate diagnosis of autoimmune encephalitis encourages prompt initiation of immunotherapy toward improved patient outcomes. However, clinical features alone may not sufficiently narrow the differential diagnosis, and awaiting autoantibody results can delay immunotherapy. To identify simple magnetic resonance imaging (MRI) characteristics that accurately distinguish 2 common forms of autoimmune encephalitis, LGI1- and CASPR2-antibody encephalitis (LGI1/CASPR2-Ab-E), from 2 major differential diagnoses, viral encephalitis (VE) and Creutzfeldt-Jakob disease (CJD). This cross-sectional study involved a retrospective, blinded analysis of the first available brain MRIs (taken 2000-2022) from 192 patients at Oxford University Hospitals in the UK and Mayo Clinic in the US. These patients had LGI1/CASPR2-Ab-E, VE, or CJD as evaluated by 2 neuroradiologists (discovery cohort; n = 87); findings were validated in an independent cohort by 3 neurologists (n = 105). Groups were statistically compared with contingency tables. Data were analyzed in 2023. MRI findings including T2 or fluid-attenuated inversion recovery (FLAIR) hyperintensities, swelling or volume loss, presence of gadolinium contrast enhancement, and diffusion-weighted imaging changes. Correlations with clinical features. Among 192 participants with MRIs reviewed, 71 were female (37%) and 121 were male (63%); the median age was 66 years (range, 19-92 years). By comparison with VE and CJD, in LGI1/CASPR2-Ab-E, T2 and/or FLAIR hyperintensities were less likely to extend outside the temporal lobe (3/42 patients [7%] vs 17/18 patients [94%] with VE; P < .001, and 3/4 patients [75%] with CJD; P = .005), less frequently exhibited swelling (12/55 [22%] with LGI1/CASPR2-Ab-E vs 13/22 [59%] with VE; P = .003), and showed no diffusion restriction (0 patients vs 16/22 [73%] with VE and 8/10 [80%] with CJD; both P < .001) and rare contrast enhancement (1/20 [5%] vs 7/17 [41%] with VE; P = .01). These findings were validated in an independent cohort and generated an area under the curve of 0.97, sensitivity of 90%, and specificity of 95% among cases with T2/FLAIR hyperintensity in the hippocampus and/or amygdala. In this study, T2 and/or FLAIR hyperintensities confined to the temporal lobes, without diffusion restriction or contrast enhancement, robustly distinguished LGI1/CASPR2-Ab-E from key differential diagnoses. These observations should assist clinical decision-making toward expediting immunotherapy. Their generalizability to other forms of autoimmune encephalitis and VE should be examined in future studies.

Clinical Spectrum, Treatment and Outcome of Children with Autoimmune Encephalitis.

To assess the clinical spectrum, treatment, and outcome of children with autoimmune encephalitis (AE). Descriptive study. Place and Duration of the Study: Department of Paediatrics, The Aga Khan University Hospital, Karachi, Pakistan, from January 2017 to December 2021. Medical records of children with a diagnosis of AE were reviewed for clinical features, treatment details, and outcomes. Outcome was defined as good (0-2) or poor (3-6) based on a modified Rankin Scale (mRS) score at 3-month follow-up. Descriptive statistics were reported and logistic regression was used to assess the prognostic factors associated with outcome. Thirty-three patients were identified with AE. Thirteen (39.3%) were antibody positive. Anti-N-methyl-D-aspartate receptor (NMDAR) antibody was seen in 92% of positive cases. Behavioural abnormalities (87.8%), seizures (81.8%), movement disorders (66.6%), psychiatric symptoms (63.6%), and mutism (33.3%) were the prominent symptoms. Thirty (91%) patients received first-line immunotherapy. Good outcome was seen in 14 (48.2%) patients. Univariable analysis showed that the odds of having poor outcome were 2.5 (95% confidence interval [CI] 0.37-16.88, p=0.34) in patients with chorea. In addition, an elevated cerebrospinal fluid (CSF) protein had an odds ratio (OR) of 8.6 (CI 0.88-84.83, p=0.064) and positive CSF antibodies had an OR of 3.7 (CI 0.79-17.72, p=0.095) for a poor outcome. Mortality was seen in 4 (12.1%) patients. A very low threshold is needed for the diagnosis of AE in children presenting with behavioural symptoms and chorea. Although the odds for poor prognosis were higher in patients with chorea, elevated CSF protein and positive CSF antibodies, the p-value did not come out significant. Autoimmune encephalitis, Antibodies, NMDAR, Immunotherapies, mRS score, Outcome.

An Autopsy-proven Case-based Review of Autoimmune Encephalitis.

Autoimmune encephalitis (AIE) is a type of immunoreactive encephalitic disorder and is recognized as the most prevalent noninfectious encephalitis. Nevertheless, the rarity of definitive AIE diagnosis through biopsy or autopsy represents a significant hurdle to understanding and managing the disease. In this article, we present the pathological findings of AIE and review the literature based on a distinct case of AIE presenting as CD8+ T-lymphocyte predominant encephalitis. We describe the clinical progression, diagnostic imaging, laboratory data, and autopsy findings of an 80-year-old deceased male patient. The patient was diagnosed with pulmonary tuberculosis 6 months before death and received appropriate medications. A week before admission to the hospital, the patient manifested symptoms such as a tendency to sleep, decreased appetite, and confusion. Although the patient temporally improved with medication including correction of hyponatremia, the patient progressed rapidly and died in 6 weeks. The brain tissue revealed lymphocytic infiltration in the gray and white matter, leptomeninges, and perivascular infiltration with a predominance of CD8+ T lymphocytes, suggesting a case of AIE. There was no detectable evidence of viral infection or underlying neoplasm. The autopsy revealed that this patient also had Alzheimer's disease, atherosclerosis, arteriolosclerosis, and aging-related tau astrogliopathy. This report emphasizes the pivotal role of pathological examination in the diagnosis of AIE, especially when serological autoantibody testing is not available or when a patient is suspected of having multiple diseases.

A complex case of autoimmune encephalitis with renal twist - A case report

Autoimmune Encephalitis (AE) presents diagnostic challenges due to its diverse symptoms. We describe a case of a 32-year-old male with fever, seizures, and altered mental status, presented at Aga Khan hospital, Karachi, Pakistan. Unusual cerebrospinal fluid findings and autoimmune markers led to AE diagnosis. Autoimmune encephalitis’s intersection with lupus nephritis required a multidisciplinary approach, resulting in significant improvement. This case highlights the importance of clinical suspicion and antibody testing in AE diagnosis and offers insights into evolving autoimmune disease management.

Navigating the diagnostic and therapeutic complexities of autoimmune encephalitis

Characterized by immune-mediated inflammation of the brain, autoimmune encephalitis (AE) encompasses a diverse array of disorders, each presenting with unique as well as overlapping clinical manifestations, and underlying autoantibodies targeting neuronal and glial surface antigens. The clinical spectrum can range from subtle cognitive and behavioural changes to severe seizures, movement disorders, and altered consciousness. However, what truly sets AE apart from other encephalitides is its potential reversibilitywhen identified early and managed appropriately. The identification of N-methyl-D-aspartate receptor (NMDAR) antibody encephalitis in 2007 heralded the discovery of a spectrum of immunotherapy-responsive AE. However, misdiagnosis remains prevalent despite diagnostic algorithms, resulting in unnecessary immunotherapies and delayed treatment of the correct diagnosis. AE diagnosis requires a judicious blend of diagnostic algorithms, antibody testing, and clinical acumen. Testing for antibodies against neuronal surface antigens, preferably in cerebrospinal fluid, is essential, but should be contextual to clinical relevance.Treatment guidelines are largely based on retrospective studies due to a dearth of randomized and prospective data. However, early immunotherapy initiation has proven to be pivotal for optimal outcomes. The therapeutic landscape in AE continues to evolve with the introduction of novel targeted immunotherapies.This review highlights the complexities, and proposes a systematic approach, to the diagnosis and treatment of AE.

Oligodendroglioma of the Brain with a Gliomatous Growth Pattern Mimicking the Radiologic Features of Autoimmune Encephalitis

In this case report of a patient with verified oligodendroglioma with gliomatous growth pattern, at primary clinical and magnetic resonance (MR) diagnosis, the diagnosis of autoimmune encephalitis (AE) was proposed due to the presence of certain radiological patterns typically seen in AE. Further investigation, including advanced MR methods such as magnetic resonance spectrometry, suggested a possible diffuse multifocal glial involvement, which was further confirmed by histological and immunohistochemical examination. The comprehensive approach of evaluating dynamic MRI data, clinical presentation and the use of extended MRI protocols may assist in precise determination of neoplastic changes in the brain tissue.

A complex case of young child with ADHD, developmental delay who developed seronegative autoimmune encephalitis exacerbated by stimulants

Autoimmune encephalitis (AE) is a group of disorders characterized by a wide clinical spectrum ranging from the typical limbic encephalitis to more complex neuropsychiatric symptoms including abnormal movements, psychosis, deficits in memory and cognition, dysautonomia, seizures, or coma. Psychiatric symptoms can occur early in the disease progress or manifest during its course. These symptoms are challenging and often slow down the diagnosis of AE. This is a crucial aspect considering that early diagnosis and management of AE are critical for a good outcome. However, there is a lack in studies outlining the exact symptomatology and specific appropriate care that would allow clinicians to achieve an early diagnosis and management. Additionally, AE in children mostly presents with neuropsychiatric symptoms and diagnosis is especially challenging in kids because of their limited capacity in describing their symptoms, the normal childhood behavioral changes and the possibility of a comorbid psychiatric diagnosis. We present a complex case of seronegative AE with comorbid ADHD (Attention Deficit Hyperactivity Disorder) and anxiety in a young six-year-old girl.

Retrospective Comparison of Patients Evaluated for Pediatric Autoimmune Encephalitis with Typical and Atypical Premorbid Neuropsychiatric Development.

Patients with neurodevelopmental disorders (NDD) (i.e. autism, developmental delay, early-onset psychiatric or seizure disorders) increasingly seek evaluation of new or exacerbated symptoms concerning for autoimmune encephalitis (AE). Clinical AE evaluation can be challenging in NDD patients with symptom overlap between anti-neuronal autoimmunity and baseline atypical neurodevelopment. This study sought to explore differences in AE features by neurodevelopmental status. This retrospective chart review included 67 children with typical development (TD) or NDD evaluated for AE at the authors' institution. AE diagnosis included seronegative AE or seropositive AE with anti-NMDAR or anti-GAD antibodies. Reported AE clinical domains, symptom onset acuity, and treatment response were compared between three groups: (1) TD children with AE (TD-AE, N = 24); (2) NDD children with AE (NDD-AE, N = 21); and (3) NDD children with a non-AE diagnosis following appropriate workup (NDD-nonAE, N = 22). Children with AE had a greater number of reported clinical domains than non-AE children with NDD (p < 0.0001) regardless of baseline developmental status. There were no observed differences in reported domains between TD-AE and NDD-AE groups. Onset acuity differed across the three groups (p = 0.04). No treatment response differences were observed between groups. NDD children with AE had a comparable number of reported clinical domains relative to TD children and a similar treatment response. NDD patients with AE had a greater number of reported clinical domains than their NDD peers without an AE diagnosis. These findings suggest that AE is a multi-domain process in both TD and NDD children.

Autoimmune anti-NMDA receptor encephalitis on the background of COVID-19: a clinical case

Background: During the new COVID-19 coronavirus infection pandemic, a growing incidence of autoimmune encephalitis cases has been observed. One of the primary problems related to patients with this highly lethal pathology is its timely early diagnostics and prescription of an optimal individual course of immunotherapy. In a debut of anti-NMDA receptor (inotropic glutamate receptor, selectively binding N-methyl D-aspartate) encephalitis, mental disorders are observed, prompting the initial admission of such patients to a psychiatric hospital. Then, the clinical picture of the disease is characterized by a significant polymorphism. In such cases, it is not always possible to suspect an autoimmune lesion of the nervous system. Clinical case description: In this article, we present a clinical case of a female patient with serologically confirmed autoimmune encephalitis against the background of the new coronavirus infection (U07.1 according to ICD-10). The disease onset involved psychiatric symptoms; the patient was transferred to the Department of neurology of the VGK BSMP No. 1 Municipal Clinical Hospital of Emergency Care No.1 from the municipal psychiatric hospital, when generalized cerebral symptoms appeared. According to the diagnostic criteria, mental disorders and generalized epileptic seizures are the most significant signs in the verification of autoimmune encephalitis. Autoimmune encephalitis was suspected based on the developed neurological symptoms and generalized epileptic seizures and confirmed by the detected anti-NMDA antibodies in the blood serum. The anti-NMDA antibody analysis in the blood and cerebrospinal fluid is the most informative way of autoimmune encephalitis diagnosis. Conclusion: Autoimmune encephalitis requires vigilance of physicians of all specialties who may encounter this disease. Timely diagnostic procedures and prescription of pathogenetically justified treatment are of importance.

Late-onset mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes syndrome with mitochondrial DNA 3243A&gt;G mutation masquerading as autoimmune encephalitis: A case report

Here, we present a unique case of mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) syndrome, which initially appeared to be autoimmune encephalitis and was ultimately confirmed as MELAS with the mitochondrial DNA 3243A>G mutation. A 58-year-old female presented with acute-onset speech impediment and auditory hallucinations, symmetrical bitemporal lobe abnormalities, clinical and laboratory findings, and a lack of relevant prodromal history, which suggested diagnosis of autoimmune encephalitis. Further work-up, in conjunction with the patient's medical history, family history, and lactate peak on brain lesions on magnetic resonance imaging, suggested a mitochondrial disorder. Mitochondrial genome analysis revealed the m.3243A>G variant in the MT-TL1 gene, which led to a diagnosis of MELAS syndrome. This case underscores the importance of considering MELAS as a potential cause of autoimmune encephalitis even if patients are over 40 years of age, as the symptoms and signs are atypical for MELAS syndrome.

Therapeutic Plasma Exchange in Treatment of Autoimmune Encephalitis: A Case Report

The present study highlights the Therapeutic Plasma Exchange in treatment of Autoimmune Encephalitis. Due to the similarities in the clinical, imaging, and laboratory findings of many forms of autoimmune and infectious encephalitis, autoimmune encephalitis is frequently a difficult clinical diagnosis. Diagnosis of autoimmune encephalitis is based on the clinical course, serological evidence of autoimmunity, EEG changes, evidence of intrathecal inflammation in the cerebrospinal fluid and neuroimaging by MRI. In view of the suspected diagnosis of Autoimmune Encephalopathy with super refractory Status Epilepticus, Methylprednisolone was later added to the treatment. This case represents an interesting scenario of sero-negative encephalitis in which an early diagnosis could be made and treatment initiated in time.

Associations of Serum Neurofilament Light Chain with Outcomes in Children with Autoimmune Encephalitis (P4-5.009)

<h3>Objective:</h3> To examine associations between serum neurofilament light chain (sNfL) levels at disease onset with markers of clinical severity in children with autoimmune encephalitis (AE). <h3>Background:</h3> Despite significant advances in the diagnosis and treatment of AE, little is known about markers of disease severity and their associations with outcomes. sNfL, a marker of axonal destruction, may fill this gap. <h3>Design/Methods:</h3> This is a longitudinal prospective case-control study of children presenting to a single tertiary center with AE (n=48) vs. an age-matched healthy control population (HC) (n=88). Clinical data and modified Rankin Scale (mRS) scores were collected using a standard CRF at baseline and at follow-up, up to one year. sNfL levels in stored samples were measured by Single Molecule Array Immunoassay (SIMOA). Volumetric analyses of key anatomic structures of brain MRIs were performed using FreeSurfer. Diffusion weighted MRI was assessed for restricted diffusion. Following standard diagnostic criteria, children were classified into those with no biological marker (antibody or genetic) and those with. We further dichotomized children into high vs. low sNFL levels. Descriptive statistics, group differences, and correlational analyses were performed using JASP version 0.16.3. <h3>Results:</h3> Baseline sNfL levels were significantly higher in patients with AE (no Ab), AE (MOG), and ANEC vs. HCs (log₂ sNfL=4.3 AE(no Ab), 2.9 AE(NMDA), 5.6 AE(MOG), 6.3(ANEC), 2.4(HC), <i>p</i>&lt;0.001). AE patients in the high sNfL group were more likely to be admitted to the ICU (<i>p</i>=0.02) and had significantly higher mRS scores at nadir (<i>p</i>=0.04), compared to patients in the low sNfL group. However, there was no significant difference in mRS scores at follow-up between groups. Baseline sNfL correlated significantly with baseline restricted diffusion (r_s(43)=0.45, <i>p</i>=0.002) and thalamic volumes (r_s(31)=0.45, <i>p</i>=0.009). <h3>Conclusions:</h3> Baseline sNfL levels may serve as a marker of disease severity in patients with AE. Future studies are needed to evaluate their associations with long-term outcomes. <b>Disclosure:</b> Ms. Da Silva has nothing to disclose. Ms. Yea has nothing to disclose. Dr. AlYanbuaawy has nothing to disclose. Dr. Matt has nothing to disclose. Dr. Longoni has nothing to disclose. Helen Branson has nothing to disclose. Logi Vidarsson has nothing to disclose. An immediate family member of Dr. Ertl-Wagner has received personal compensation for serving as an employee of Siemens Healthineers. Dr. Yeh has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Roche. Dr. Yeh has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for PRIME. Dr. Yeh has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Novartis. Dr. Yeh has received personal compensation in the range of $500-$4,999 for serving as an Editor, Associate Editor, or Editorial Advisory Board Member for Elsevier. The institution of Dr. Yeh has received research support from Biogen. The institution of Dr. Yeh has received research support from Stem Cell Network. The institution of Dr. Yeh has received research support from CIHR. The institution of Dr. Yeh has received research support from Ontario Institute for Regenerative Medicine. The institution of Dr. Yeh has received research support from National MS Society. The institution of Dr. Yeh has received research support from NIH. The institution of Dr. Yeh has received research support from SickKids Foundation. The institution of Dr. Yeh has received research support from CMSC. The institution of Dr. Yeh has received research support from MSSC.

Characterization of the Common Symptomology and Great Mimickers of Autoimmune Encephalitis (P4-5.011)

<h3>Objective:</h3> To identify clinical and systemic variables associated with mimickers of Autoimmune Encephalitis (AE). <h3>Background:</h3> The classical presentation of AE includes acute or subacute onset of impaired memory and cognition, in combination with progressive neurologic symptoms which may include abnormal movements, seizures, psychosis, and balance, speech, or vision problems. However, diagnosis can be challenging due to broad differential diagnoses and variable presentations of patients with suspected AE. Greater awareness of AE has led to increased consideration of AE as a potential etiology of neurologic symptoms, and accordingly, misattribution of symptoms to AE in some instances. <h3>Design/Methods:</h3> We performed a single-center retrospective chart review of 212 patients from the University of Utah Health identified by query of the ICD-10 code G04.81: Other encephalitis and encephalomyelitis between January 2012–August 2022, which is the diagnostic code inclusive of AE and other related or nonspecific encephalitis. <h3>Results:</h3> We describe the patient demographics of this cohort, as well as relevant clinical data including the predominant presenting symptom(s), cerebrospinal fluid characteristics, electroencephalography and neuroaxis imaging findings, suspected initial diagnosis, timing and duration of treatment interventions (including immunomodulatory therapy), final diagnosis, and outcomes. <h3>Conclusions:</h3> The diagnosis of AE remains challenging, especially in patient presentations with a predominant psychiatric phenotype at onset, or in those with atypical features. Recognition of the most common pitfalls to diagnosis and disease mimics may improve timely and accurate recognition of causative etiologies and help to direct the most appropriate treatments and interventions. <b>Disclosure:</b> Miss Soneji has nothing to disclose. Miss Shapiro has nothing to disclose. Dr. Wright has nothing to disclose. Dr. Noroozi Gilandehi has nothing to disclose. Miss Francis has nothing to disclose. Dr. Smith has nothing to disclose. Mr. Wong has nothing to disclose. Dr. Clardy has received personal compensation for serving as an employee of Veterans Health Administration (VHA). Dr. Clardy has received personal compensation for serving as an employee of University of Utah Health. Dr. Clardy has received personal compensation in the range of $10,000-$49,999 for serving as an Editor, Associate Editor, or Editorial Advisory Board Member for Neurology/AAN Publications. The institution of Dr. Clardy has received research support from Sumaira Foundation for NMO. The institution of Dr. Clardy has received research support from Western Institute for Veteran Research. The institution of Dr. Clardy has received research support from NIH/NINDS. Dr. Clardy has received personal compensation in the range of $500-$4,999 for serving as a AAN Summer Meeting CoDirector Travel and Lodging with AAN. Dr. Clardy has received personal compensation in the range of $500-$4,999 for serving as a Grand Rounds Travel and Lodging with U of Iowa. Dr. Clardy has received personal compensation in the range of $500-$4,999 for serving as a Speaker Honoraria for Grand Rounds with Barrow Neurological Institute. Dr. Clardy has received personal compensation in the range of $500-$4,999 for serving as a Speaker Honoraria for Grand Rounds with Beaumont Health.

Autoimmune Encephalitis: A Case Report from the Neurology Department of the Doctor Joseph Guislain Neuropsychiatric Centre in Lubumbashi and Review of the Literature

The term encephalitis refers to the inflammation of the parenchyma of the central nervous system, located in the cranial cavity. We report the case of a 17-year-old female patient with a history of tuberculous gonarthritis, who was admitted for convulsive seizures complicated by status epilepticus. Medical imaging did not reveal any brain lesions and biology revealed an elevated PCT. Through this case, we underline the risk of diagnostic errancy and thus of delay in the treatment of autoimmune encephalitis which, in 70% of cases, is effective. It also seemed important to us to insist on the fact that the absence of autoantibodies does not invalidate the diagnosis of autoimmune encephalitis, especially in developing countries where the technical platform to search for them is lacking both in terms of equipment and human resources. Finally, it should be noted that new autoantibodies are found almost every year by teams in developed countries. Thus, in front of any acute or sub-acute neurological picture not explained, it is necessary to think about autoimmune encephalitis and to start an immunomodulatory treatment, which guarantees the cure or the substantial improvement in most cases.

Can Autoimmune Encephalitis Occur with Negative Markers? A Rare Case Report

In our case, we present a case of a 27-year-old male who presented with progressively worsening altered mental status and seizures. Over the course of his admission to the hospital and intensive care unit, laboratory testing failed to find an offending agent to his presentation. Testing did result in the diagnosis of encephalitis, but an underlying cause was not found. After careful exclusion of bacterial, viral, and other types of encephalopathy, autoimmune encephalopathy was diagnosed despite the absence of commonly used markers of autoimmune encephalopathy. The presentation and symptoms of our patient led to a wide range of differentials, and a high index of suspicion was needed throughout his admission in order to obtain the appropriate tests. Although appropriate testing might be ordered, due to the sensitivities and specificities of all laboratory tests, these objective tests do produce false negative results at times. It is in these times that one must weigh the physical exam, clinical judgment, and the process of elimination to diagnose an underlying pathology. Autoimmune Encephalitis diagnosis can be broken down into possible, probable, and definitive diagnoses based on antibody testing results. In this case, we present a patient with probable autoimmune encephalitis that failed to yield positive autoimmune markers after extensive testing of other possible causes of encephalitis.

Clinical characteristics and short-term outcomes of autoimmune encephalitis in adults

To characterize clinical, paraclinical features and short-term outcomes in different types of autoimmune encephalitis (AE) in a one-center cohort of Russian patients, as well as to evaluate the frequency and significance of the joint expression of antineuronal and anti-glial antibodies (Abs) in AE. Forty-one patients were diagnosed with AE at the Research Center of Neurology from November 2020 to December 2022. Demographic, clinical characteristics, results of laboratory tests, MRI of brain, treatment and outcomes of disease were analyzed. The analysis of Abs to glial antigens (myelin-oligodendrocyte glycoprotein - MOG, glial fibrillar acidic protein - GFAP, aquaporin 4 - AQP-4) was performed by indirect immunofluorescence assay (Euroimmun, Germany). In 24 (58.5%) patients was established definite AE, confirmed by specific Abs detection; in 2 (4.9%) - definite limbic encephalitis, in 15 (36.6%) - seronegative probable AE (including 3 cases of Hashimoto's encephalitis). GFAP-Abs in cerebrospinal fluid (CSF) were detected only in two patients - with clinical and MRI-picture of autoimmune GFAP-astrocytopathy (A-GFAP-A). GFAP- and MOG-Abs in the blood were detected in 25.7% and 6%, respectively, AQP-4-Abs were not detected. There were no correlations between co-expression with glial Abs and clinical characteristics. Systemic and antithyroid Abs were present in 15% and 31%, respectively. Paraneoplastic AE accounted for 22%. For the first time in the Russian population, 2 cases of A-GFAP-A, 6 cases of AE associated with COVID-19 were described. The most common first syndrome were epileptic seizure (34%), psychiatric (29%) and cognitive (14%) disorders. Relapses of AE was observed in 22%. Inflammatory changes in CSF were detected in 41%, focal changes on MRI in 68%. First-line immune therapy was performed in all patients, 85% of cases received pulse therapy with methylprednisolone. Second-line immune therapy (rituximab or cyclophosphamide intravenously) was performed in 19.5%, 78% of patients achieved significant improvement during treatment (scores ≤2 on the modified Rankin scale). The results allow us to consider COVID-19 as a trigger of AE. The absence of detection of GFAP-Abs in CSF in patients with other types of AE contributes to the confirmation of the specificity of GFAP-seropositivity of CSF for the diagnosis of A-GFAP-A. The expression of GFAP- and MOG-Abs in AE can serve as confirmation of the immuno-mediated etiology of the disease, which is especially important for the AE diagnosis in the absence of antineuronal Abs.

Early predictors of new-onset immune-related seizures: a preliminary study

BackgroundApproximately 60% of patients with autoimmune encephalitis (AE) exhibit secondary acute symptomatic seizures and showed highly sensitive to immunotherapy. However, it is difficult for many patients to receive early immunotherapy since the early identification of the cause in AE is more complex. This study aimed to investigate the early predictors of initial immune-related seizures and to guide the evaluation of treatment and prognosis.MethodsOne hundred and fifty-four patients with new-onset “unknown etiology” seizures with a course of disease less than 6 months were included. Serum and/or cerebrospinal fluid neuron-specific autoantibodies (NSAbs), including N-methyl-D-aspartate receptor (NMDAR), α-amino-3-hydroxy-5- Methyl-4-isoxazole propionic acid receptor 1 (AMPAR1), AMPAR2, anti-leucine rich glioma inactivated 1 antibody (LGI1), anti-gamma-aminobutyric acid type B receptor (GABABR), anti-contact protein-related protein-2 (CASPR2) were used to screen for immune etiology of the seizures. In addition, patients with epilepsy and encephalopathy were also examined via brain MRI, long-term video EEG, antibody prevalence in epilepsy and encephalopathy (APE2) score, and modified Rankin Scale (mRS). A logistic regression model was used to analyze the early predictors of immune etiology.ResultsThirty-four cases (22.1%) were positive for NSAbs. Among all 154 patients, 23 cases of autoimmune encephalitis (AE) (21 cases of NSAbs positive), 1 case of ganglionic glioma (NSAbs positive), 130 cases of epilepsy or seizures (12 cases of NSAbs positive) were recorded. Also, there were 17 patients (11.0%) with APE2 ≥ 4 points, and all of them met the clinical diagnosis of AE. The sensitivity and specificity of APE2 ≥ 4 points for predicting AE were 73.9% and 100%. The results of multivariate analysis showed that the NSAbs and APE2 scores independently influenced the early prediction of initial immune-related seizures (P < 0.05).ConclusionNSAbs and APE2 scores could act as early predictors of initial immune-related seizures.