Autoimmune encephalitis in glial fibrillary acidic protein astrocytopathy.

Autoimmune encephalitis due to glial fibrillar acidic protein (GFAP) astrocytopathy is a rare cause of subacute neuropsychiatric changes. In this case, a young patient presented with a viral prodrome and meningismus, followed by progressive encephalopathy and movement disorders over the span of 2 weeks. Due to his clinical trajectory, inflammatory cerebrospinal fluid (CSF) analysis, initial normal brain imaging and negative serum autoimmune encephalopathy panel, his initial diagnosis was presumed viral meningoencephalitis. The recurrence and progression of neuropsychiatric symptoms and myoclonus despite antiviral treatment prompted further investigation, inclusive of testing for CSF autoimmune encephalopathy autoantibodies, yielding a clinically meaningful, positive GFAP autoantibody. This case highlights the importance of appropriately testing both serum and CSF autoantibodies when an autoimmune encephalitic process is considered. Through this case, we review the clinical and radiographic manifestations of GFAP astrocytopathy, alongside notable pearls pertaining to this autoantibody syndrome and its management.

Metronidazole-Induced Encephalopathy With Probable Crohn Encephalitis: A Case Report.

OBJECTIVES: Metronidazole central nervous system toxicity is a rare finding in patients receiving the medication. We report a peculiar case of metronidazole central nervous system toxicity in which both the underlying condition (Crohn disease) and the drugs used to treat it are potential causes of encephalopathy. METHODS: A 26-year-old female with 6-year history of Crohn's disease for 6 years presented acute-onset encephalopathy. We provide bibliographic evidence to support metronidazole toxicity and potential Crohn disease-associated neurologic involvement. RESULTS: The patient presented dystonia, cerebellar ataxia, and altered mental status. Magnetic resonance imaging of the brain revealed typical findings of metronidazole toxicity and white matter involvement of the centrum semiovale. Immunoelectrophoresis and immunofixation of serum and cerebrospinal fluid proteins were consistent with a systemic inflammatory process. We concluded on an association between drug toxicity and probable Crohn-associated neurologic involvement. Metronidazole was stopped and the patient was placed on vitamin therapy and diazepam to control dystonia. She deteriorated and was transferred to the intensive care unit where she expired. CONCLUSIONS: Acute behavioral changes in a young patient constitute an emergency and differential diagnoses should include infective, inflammatory, metabolic, and toxic causes. Metronidazole is a potential toxic etiology.

Management of Autoimmune Encephalitis in a 7-Year-Old Child With CTLA-4 Haploinsufficiency and AMPA Receptor Antibodies: A Case Report.

OBJECTIVES: We report on the therapeutic management of early-onset severe neurologic symptoms in cytotoxic T lymphocyte antigen-4 haploinsufficiency (CTLA-4h) and the presence of antibodies to the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) as an important finding. METHODS: This is a case report from a Dutch academic hospital. Repeated clinical examinations, repeated brain MRI and extended diagnostics on serum and CSF were performed. We used the CARE checklist. RESULTS: A 7-year-old boy was diagnosed with CTLA-4h based on family screening. On diagnosis, he had mild chronic diarrhea and autism spectrum disorder, but no abnormalities in extensive laboratory screening. Six months later, he presented with sudden-onset autoimmune encephalitis. Repeated brain MRI revealed no abnormalities, but immunohistochemistry analysis on serum and CSF showed the presence of AMPAR antibodies. Treatment was initially focused on immunomodulation and targeted CTLA-4 replacement therapy. Because of the persistent fluctuating cerebellar and neuropsychiatric symptoms and the potential clinical significance of the AMPAR antibodies, treatment was intensified with repetition of first-line immunomodulation and rituximab. This combined therapy resulted in sustained clinical improvement and served as a bridge to curative hematopoietic stem cell transplantation. DISCUSSION: This case illustrates the rare early onset of autoimmune encephalitis and presence of AMPAR antibodies in CTLA-4h. Targeted CTLA-4 replacement therapy resulted in a partial response. However, awaiting its optimal therapeutic effect, refractory CNS symptoms required intensification of immunomodulation. The identification of AMPAR antibodies guided our treatment decisions. CLASSIFICATION OF EVIDENCE: This provides Class IV evidence. It is a single observational study without controls.

Reversible encephalitis-like episodes in fragile X-associated tremor/ataxia syndrome: a case report.

BACKGROUND: Fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder caused by CGG repeat expansion of FMR1 gene. Both FXTAS and neuronal intranuclear inclusion disease (NIID) belong to polyglycine diseases and present similar clinical, radiological, and pathological features, making it difficult to distinguish these diseases. Reversible encephalitis-like attacks are often observed in NIID. It is unclear whether they are presented in FXTAS and can be used for differential diagnosis of NIID and FXTAS. CASE PRESENTATION: A 63-year-old Chinese male with late-onset gait disturbance, cognitive decline, and reversible attacks of fever, consciousness impairment, dizziness, vomiting, and urinary incontinence underwent neurological assessment and examinations, including laboratory tests, electroencephalogram test, imaging, skin biopsy, and genetic test. Brain MRI showed T2 hyperintensities in middle cerebellar peduncle and cerebrum, in addition to cerebellar atrophy and DWI hyperintensities along the corticomedullary junction. Lesions in the brainstem were observed. Skin biopsy showed p62-positive intranuclear inclusions. The possibilities of hypoglycemia, lactic acidosis, epileptic seizures, and cerebrovascular attacks were excluded. Genetic analysis revealed CGG repeat expansion in FMR1 gene, and the number of repeats was 111. The patient was finally diagnosed as FXTAS. He received supportive treatment as well as symptomatic treatment during hospitalization. His encephalitic symptoms were completely relieved within one week. CONCLUSIONS: This is a detailed report of a case of FXTAS with reversible encephalitis-like episodes. This report provides new information for the possible and rare features of FXTAS, highlighting that encephalitis-like episodes are common in polyglycine diseases and unable to be used for differential diagnosis.

Antibody-positive autoimmune encephalitis and paraneoplastic neurological syndrome: A Swedish case series.

OBJECTIVE: This study aimed to explore the clinical characteristics and temporal disease course of patients with autoimmune encephalitis (AE) and paraneoplastic neurological syndrome (PNS) in Sweden. METHODS: Thirty-seven antibody-positive AE and PNS cases were identified in the Healthcare region Mid Sweden between 2015 and 2019. Clinical data were collected through a retrospective review of electronic health records. Patients were divided into three subgroups based on antibody type: neuronal surface antibodies (NSAbs), onconeural antibodies, and anti-GAD65 antibodies. RESULTS: Nineteen patients had NSAbs, 11 onconeural antibodies, and seven anti-GAD65 antibodies. Anti-LGI1 and anti-NMDAR were the most frequently detected NSAbs, with anti-NMDAR cases having an older-than-expected age distribution (median age 40, range 17-72). Only 11 of 32 (30%) of patients had findings suggesting encephalitis on initial MRI, but 28 of 31 (90%) had pathological findings on initial cerebrospinal fluid analysis. All patients but one had abnormal EEG findings. Median time to immunotherapy was comparable among the three subgroups, whereas patients with anti-LGI1, anti-CASPR2, and anti-IgLON5 had an eightfold longer time to immunotherapy than anti-NMDAR and anti-GABA-B (p = .0016). There was a seasonal variation in onset for patients with non-tumor-related NSAbs and anti-GAD65 antibodies, with most patients (72%) falling ill in spring or summer. CONCLUSION: Swedish patients with AE and PNS had similar clinical characteristics as previously described cohorts from other geographical regions except for anti-NMDAR encephalitis, with older onset than expected. The onset of non-tumor-related AE occurred predominantly in the warm seasons, and AE with a more insidious onset was associated with delayed treatment initiation.

Corticospinal tract hyperintensity in patients with LGI1-antibody encephalitis and other central nervous system disorders with neuroglial antibodies.

The frequency of corticospinal tract (CST) T2/FLAIR hyperintensity in disorders with neuroglial antibodies is unclear. Herein, we retrospectively reviewed brain MRIs of 101 LGI1-antibody encephalitis patients, and observed CST hyperintensity in 30/101 (30%). It was mostly bilateral (93%), not associated with upper motor neuron signs/symptoms (7%), and frequently decreased over time (39%). In a systematic review including patients with other neuroglial antibodies, CST hyperintensity was reported in 110 with neuromyelitis optica (94%), myelin oligodendrocyte glycoprotein-associated disease (2%), Ma2-antibody (3%) and GAD65-antibody paraneoplastic neurological syndrome (1%). CST hyperintensity is not an infrequent finding in LGI1-Ab encephalitis and other disorders with neuroglial antibodies.

Comparative Study of Paraneoplastic and Nonparaneoplastic Autoimmune Encephalitis With GABABR Antibodies.

BACKGROUND AND OBJECTIVES: While patients with paraneoplastic autoimmune encephalitis (AE) with gamma-aminobutyric-acid B receptor antibodies (GABABR-AE) have poor functional outcomes and high mortality, the prognosis of nonparaneoplastic cases has not been well studied. METHODS: Patients with GABABR-AE from the French and the Dutch Paraneoplastic Neurologic Syndromes Reference Centers databases were retrospectively included and their data collected; the neurologic outcomes of paraneoplastic and nonparaneoplastic cases were compared. Immunoglobulin G (IgG) isotyping and human leukocyte antigen (HLA) genotyping were performed in patients with available samples. RESULTS: A total of 111 patients (44/111 [40%] women) were enrolled, including 84 of 111 (76%) paraneoplastic and 18 of 111 (16%) nonparaneoplastic cases (cancer status was undetermined for 9 patients). Patients presented with seizures (88/111 [79%]), cognitive impairment (54/111 [49%]), and/or behavioral disorders (34/111 [31%]), and 54 of 111 (50%) were admitted in intensive care unit (ICU). Nonparaneoplastic patients were significantly younger (median age 54 years [range 19-88] vs 67 years [range 50-85] for paraneoplastic cases, p < 0.001) and showed a different demographic distribution. Nonparaneoplastic patients more often had CSF pleocytosis (17/17 [100%] vs 58/78 [74%], p = 0.02), were almost never associated with KTCD16-abs (1/16 [6%] vs 61/70 [87%], p < 0.001), and were more frequently treated with second-line immunotherapy (11/18 [61%] vs 18/82 [22%], p = 0.003). However, no difference of IgG subclass or HLA association was observed, although sample size was small (10 and 26 patients, respectively). After treatment, neurologic outcome was favorable (mRS ≤2) for 13 of 16 (81%) nonparaneoplastic and 37 of 84 (48%) paraneoplastic cases (p = 0.03), while 3 of 18 (17%) and 42 of 83 (51%) patients had died at last follow-up (p = 0.008), respectively. Neurologic outcome no longer differed after adjustment for confounding factors but seemed to be negatively associated with increased age and ICU admission. A better survival was associated with nonparaneoplastic cases, a younger age, and the use of immunosuppressive drugs. DISCUSSION: Nonparaneoplastic GABABR-AE involved younger patients without associated KCTD16-abs and carried better neurologic and vital prognoses than paraneoplastic GABABR-AE, which might be due to a more intensive treatment strategy. A better understanding of immunologic mechanisms underlying both forms is needed.

Study on clinical features and factors related to long-term outcomes of antibody-negative autoimmune encephalitis.

OBJECTIVE: To delineate the clinical characteristics of antibody-negative autoimmune encephalitis (AE) and to investigate factors associated with long-term outcomes among antibody-negative AE. METHODS: Patients diagnosed with antibody-negative AE were recruited from January 2016 to December 2022 at the Second Xiangya Hospital of Central South University. The study assessed the long-term outcomes of antibody-negative AE using the modified Rankin scale (mRS) and the Clinical Assessment Scale in Autoimmune Encephalitis (CASE). Predictors influencing long-term outcomes were subsequently analyzed. External validation of RAPID scores (refractory status epilepticus [RSE], age of onset ≥60 years, ANPRA [antibody-negative probable autoimmune encephalitis], infratentorial involvement, and delay of immunotherapy ≥1 month) was performed. RESULTS: In total, 100 (47 females and 53 males) antibody-negative AE patients were enrolled in this study, with approximately 49 (49%) experiencing unfavorable long-term outcomes (mRS scores ≥3). Antibody-negative AE was subcategorized into ANPRA, autoimmune limbic encephalitis (LE), and acute disseminated encephalomyelitis (ADEM). Psychiatric symptoms were prevalent in LE and ANPRA subtypes, while weakness and gait instability/dystonia were predominant in the ADEM subtype. Higher peak CASE scores (odds ratio [OR] 1.846, 95% confidence interval [CI]: 1.163-2.930, p = 0.009) and initiating immunotherapy within 30 days (OR 0.210, 95% CI: 0.046-0.948, p = 0.042) were correlated with long-term outcomes. Receiver operating characteristic (ROC) analysis returned that the RAPID scores cutoff of 1.5 best discriminated the group with poor long-term outcomes (sensitivity 85.7%, specificity 56.9%). INTERPRETATION: The ANPRA subtype exhibited poorer long-term outcomes compared to LE and ADEM subtypes, and early immunotherapy was crucial for improving long-term outcomes in antibody-negative AE. The use of RAPID scoring could aid in guiding clinical decision making.

Case report: Shingles-associated probable Bickerstaff brainstem encephalitis with IgM anti-sulfatide positivity.

Background: Bickerstaff brainstem encephalitis (BBE) is a rare disease considered caused by acute demyelination of the brainstem, most often resulting from secondary autoimmune responses. To our knowledge, this is the first probable case report of shingles-associated BBE with anti-sulfatide IgM positivity. Case presentation: We report the case of an 83-year-old woman with symptoms of progressive limb weakness, difficulty swallowing food, and disturbed consciousness that occurred 4 weeks following herpes zoster infection. Autoimmune anti-sulfatide antibodies were positive and fluid-attenuated inversion recovery (FLAIR) sequences revealed clear high signal intensity in pons and bilateral thalamus. Our patient's condition improved markedly with glucocorticoid treatment. After 2 months of treatment, our patient was fully recovered. We considered that for her case, BBE is the most appropriate diagnosis. Conclusions: We emphasize the importance of a careful medical history and assessment of clinical symptoms, performing MRI, testing autoimmune antibodies for rapid diagnosis, and ruling out differential diagnoses. Further studies involving more patients with BBE with IgM anti-sulfatide autoantibodies will increase the understanding of the clinical characteristics and advance the diagnosis and treatment of this syndrome. Meanwhile, it is crucial for dermatologists to know about this severe neurological complication following shingles.

Cardiopulmonary Coupling Spectrogram as an Ambulatory Method for Assessing Sleep Disorders in Patients With Autoimmune Encephalitis.

BACKGROUND AND OBJECTIVES: Sleep disorders are a common and important clinical feature in patients with autoimmune encephalitis (AE); however, they are poorly understood. We aimed to evaluate whether cardiopulmonary coupling (CPC), an electrocardiogram-based portable sleep monitoring technology, can be used to assess sleep disorders in patients with AE. METHODS: Patients fulfilling the diagnostic criteria of AE were age- and sex-matched with recruited healthy control subjects. All patients and subjects received CPC testing between August 2020 and December 2022. Demographic data, clinical information, and Pittsburgh Sleep Quality Index (PSQI) scores were collected from the medical records. Data analysis was performed using R language programming software. RESULTS: There were 60 patients with AE (age 26.0 [19.8-37.5] years, male 55%) and 66 healthy control subjects (age 30.0 [25.8-32.0] years, male 53%) included in this study. Compared with healthy subjects, patients with AE had higher PSQI scores (7.00 [6.00-8.00] vs 3.00 [2.00-4.00], p < 0.001), lower sleep efficiency (SE 80% [71%-87%] vs 92% [84%-95%], p < 0.001), lower percentage of high-frequency coupling (25% [14%-43%] vs 45% [38%-53%], p < 0.001), higher percentage of REM sleep (19% ± 9% vs 15% ± 7%, p < 0.001), higher percentage of wakefulness (W% 16% [11%-25%] vs 8% [5%-16%], p = 0.074), higher low-frequency to high-frequency ratio (LF/HF 1.29 [0.82-2.40] vs 0.91 [0.67-1.29], p = 0.001), and a higher CPC-derived respiratory disturbance index (9.78 [0.50-22.2] vs 2.95 [0.40-6.53], p < 0.001). Follow-up evaluation of 14 patients showed a decrease in the PSQI score (8.00 [6.00-9.00] vs 6.00 [5.00-7.00], p = 0.008), an increased SE (79% [69%-86%] vs 89% [76%-91%], p = 0.030), and a decreased W% (20% [11%-30%] vs 11% [8%-24], p = 0.035). Multiple linear regression indicated that SE (-7.49 [-9.77 to -5.21], p < 0.001) and LF/HF ratio (0.37 [0.13-0.6], p = 0.004) were independent factors affecting PSQI scores in patients with AE. DISCUSSION: Sleep disorders with autonomic dysfunction are common in patients with AE. Improvements in the PSQI score and SE precede the restoration of sleep microstructural disruption in the remission stage. CPC parameters may be useful in predicting sleep disorders in patients with AE.

[The diagnostic challenge of autoimmune encephalitis]. / Le défi diagnostique des encéphalites auto-immunes.

Autoimmune encephalitis encompasses a spectrum of neurological disorders characterized by an autoimmune response directed against neurons and glia. Around two-thirds of cases exhibit autoantibodies targeting neuronal or glial antigens in the cerebrospinal fluid and/or serum. The diagnosis is based on specific criteria combining a subacute clinical presentation and complementary test results. However, approximately one-quarter of patients do not present any paraclinical abnormalities, making the diagnosis complex. Testing for anti-antibodies is pivotal for diagnosis, and their interpretation should be contextual. Best practices for anti-neural antibody detection involve appropriate sample collection and confirmation of positive results in relation to the clinical picture.

L'encéphalite auto-immune comprend un spectre de troubles neurologiques caractérisés par une réponse auto-immunitaire dirigée contre les neurones et les cellules gliales. Environ deux tiers des cas présentent des autoanticorps dirigés contre des antigènes neuronaux et gliaux dans le liquide céphalorachidien et/ou le sérum. Le diagnostic repose sur des critères spécifiques combinant une présentation clinique subaiguë et des résultats d'examens complémentaires. Environ un quart des patients ne présente pas d'anomalie paraclinique, rendant le diagnostic complexe. La recherche des autoanticorps est cruciale pour le diagnostic de certitude et son interprétation doit être contextuelle. Les bonnes pratiques pour leur dosage impliquent le prélèvement d'échantillons appropriés et la confirmation des résultats positifs par rapport au tableau clinique.

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

INTRODUCTION: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

B-cell targeted therapies in autoimmune encephalitis: mechanisms, clinical applications, and therapeutic potential.

Autoimmune encephalitis (AE) broadly refers to inflammation of the brain parenchyma mediated by autoimmune mechanisms. In most patients with AE, autoantibodies against neuronal cell surface antigens are produced by B-cells and induce neuronal dysfunction through various mechanisms, ultimately leading to disease progression. In recent years, B-cell targeted therapies, including monoclonal antibody (mAb) therapy and chimeric antigen receptor T-cell (CAR-T) therapy, have been widely used in autoimmune diseases. These therapies decrease autoantibody levels in patients and have shown favorable results. This review summarizes the mechanisms underlying these two B-cell targeted therapies and discusses their clinical applications and therapeutic potential in AE. Our research provides clinicians with more treatment options for AE patients whose conventional treatments are not effective.

Autoimmune encephalitis mediated by postvaccination and infection of SARS-CoV-2 in a patient with a narcolepsy type 1. / Encefalitis autoinmune tras vacunación e infección por el SARS-CoV-2 en un paciente con narcolepsia de tipo 1.

INTRODUCTION: We present a narcolepsy type 1 patient that develop an autoimmune encephalitis post vaccine and/or a SARS-CoV-2 infection. CASE REPORT: At 23 years old, the patient was referred to the emergency room with difficult speaking, headache and tremor followed by changes in behavior, autonomic dysfunction, right focal motor seizure and lethargy. He has received seven weeks before mRNA-1273 (Moderna) vaccine followed by a SARS-CoV-2 infection four weeks after vaccination (positive antigen test). RESULTS: The neurological examination was normal (visual fields, cranial nerves, motor, sensory and reflexes). Nasopharyngeal swab polymerase chain reaction (PCR) testing for COVID-19 was negative. Cerebrospinalfluid (CSF) had highly elevated protein and lymphocytic pleocytosis. CSF bacterial and fungal cultures for viral infections were negative. Brain magnetic resonance imaging (MRI) showed no abnormality on the non-enhanced sequences but the diffusion weighted imaging showed restricted diffusion with high signal on the left hemisphere mainly in the cerebral cortex with a gyro morphology, patched distribution with involvement of the temporal and frontal lobes. Chest, abdomen and pelvis computed tomography; pelvic and scrotum ultrasound, showed no malignancy. Onconeural antibodies were negative. The patient was treated with plasmapheresis and corticosteroids with a good clinical outcome and near complete resolution of the MRI abnormalities. CONCLUSION: The patient fulfilled the diagnostic criteria for autoimmune encephalitis with subacute onset. COVID-19 infection and vaccination could constitute a risk in a patient with narcolepsy as in this case and, could help to provide better understanding of the implication of immune-mediated processes in the pathophysiology of the diseases.

TITLE: Encefalitis autoinmune tras vacunación e infección por el SARS-CoV-2 en un paciente con narcolepsia de tipo 1.Introducción. Presentamos un paciente diagnosticado de narcolepsia de tipo 1 que desarrolló una encefalitis autoinmune posvacunal y/o tras una infección por el SARS-CoV-2. Caso clínico. Paciente de 23 años que es remitido a urgencias por trastorno del lenguaje y temblor, acompañados de cefalea, trastorno del comportamiento, disfunción autonómica, crisis focal motora derecha y letargo. El paciente había sido vacunado siete semanas antes con la primera dosis de la vacuna Moderna (ARN mensajero) y, cuatro semanas después de la vacunación, presentó una infección por el SARS-CoV-2 con test de antígenos positivo. Resultados. La exploración neurológica mostró un nivel de conciencia normal y una afasia mixta de predominio motor (campimetría, pares craneales, reflejos y sensibilidad normales). El test de reacción en cadena de la polimerasa para la COVID-19 fue negativo. En el líquido cefalorraquídeo se apreció una linfocitosis y proteínas elevadas. Los cultivos para hongos y bacterias fueron negativos. Los anticuerpos onconeuronales fueron normales. La resonancia magnética cerebral mostró en la secuencia de difusión una restricción con afectación cortical y morfología giral en el hemisferio cerebral izquierdo, y distribución parcheada con afectación de lóbulo frontal y temporal izquierdos. Una tomografía axial computarizada de tórax-abdomen-pelvis fue normal, al igual que las ecografías pélvica y escrotal. Al paciente se le trató con plasmaféresis y corticoides, con buena evolución clínica y resolución casi completa de las anomalías en la neuroimagen. Conclusión. Se trata de un paciente con narcolepsia de tipo 1 con criterios de encefalitis autoinmune de comienzo subagudo. La infección por el SARS-CoV-2 o la vacunación, o ambas, constituyen un riesgo para desarrollar una o más enfermedades autoinmunes con la edad ­como sucede en este caso­, lo que permite comprender la implicación de procesos inmunomediados en la fisiopatología de estas enfermedades.

Predictors and Clinical Characteristics of Relapses in LGI1-Antibody Encephalitis.

BACKGROUND AND OBJECTIVES: Relapses occur in 15%-25% of patients with leucine-rich glioma-inactivated 1 antibody (LGI1-Ab) autoimmune encephalitis and may cause additional disability. In this study, we clinically characterized the relapses and identified factors predicting their occurrence. METHODS: This is a retrospective chart review of patients with LGI1-Ab encephalitis diagnosed at our center between 2005 and 2022. Relapse was defined as worsening of previous or appearance of new symptoms after at least 3 months of clinical stabilization. RESULTS: Among 210 patients, 30 (14%) experienced a total of 33 relapses. The median time to first relapse was 23.9 months (range: 4.9-110.1, interquartile range [IQR]: 17.8). The CSF was inflammatory in 11/25 (44%) relapses, while LGI1-Abs were found in the serum in 16/24 (67%) and in the CSF in 12/26 (46%); brain MRI was abnormal in 16/26 (62%) relapses. Compared with the initial episode, relapses manifested less frequently with 3 or more symptoms (4/30 patients, 13% vs 28/30, 93%; p < 0.001) and had lower maximal modified Rankin scale (mRS) score (median 3, range: 2-5, IQR: 1 vs 3, range: 2-5, IQR: 0; p = 0.001). The median mRS at last follow-up after relapse (2, range: 0-4, IQR: 2) was significantly higher than after the initial episode (1, range: 0-4, IQR: 1; p = 0.005). Relapsing patients did not differ in their initial clinical and diagnostic features from 85 patients without relapse. Nevertheless, residual cognitive dysfunction after the initial episode (hazard ratio:13.8, 95% confidence interval [1.5; 129.5]; p = 0.022) and no administration of corticosteroids at the initial episode (hazard ratio: 4.8, 95% confidence interval [1.1; 21.1]; p = 0.036) were significantly associated with an increased risk of relapse. DISCUSSION: Relapses may occur years after the initial encephalitis episode and are usually milder but cause additional disability. Corticosteroid treatment reduces the risk of future relapses, while patients with residual cognitive dysfunction after the initial episode have an increased relapse risk.

Neonatal brain inflammation enhances methamphetamine-induced reinstated behavioral sensitization in adult rats analyzed with explainable machine learning.

Neonatal brain inflammation produced by intraperitoneal (i.p.) injection of lipopolysaccharide (LPS) results in long-lasting brain dopaminergic injury and motor disturbances in adult rats. The goal of the present work is to investigate the effect of neonatal systemic LPS exposure (1 or 2 mg/kg, i.p. injection in postnatal day 5, P5, male rats)-induced dopaminergic injury to examine methamphetamine (METH)-induced behavioral sensitization as an indicator of drug addiction. On P70, subjects underwent a treatment schedule of 5 once daily subcutaneous (s.c.) administrations of METH (0.5 mg/kg) (P70-P74) to induce behavioral sensitization. Ninety-six hours following the 5th treatment of METH (P78), the rats received one dose of 0.5 mg/kg METH (s.c.) to reintroduce behavioral sensitization. Hyperlocomotion is a critical index caused by drug abuse, and METH administration has been shown to produce remarkable locomotor-enhancing effects. Therefore, a random forest model was used as the detector to extract the feature interaction patterns among the collected high-dimensional locomotor data. Our approaches identified neonatal systemic LPS exposure dose and METH-treated dates as features significantly associated with METH-induced behavioral sensitization, reinstated behavioral sensitization, and perinatal inflammation in this experimental model of drug addiction. Overall, the analysis suggests that the implementation of machine learning strategies is sensitive enough to detect interaction patterns in locomotor activity. Neonatal LPS exposure also enhanced METH-induced reduction of dopamine transporter expression and [3H]dopamine uptake, reduced mitochondrial complex I activity, and elevated interleukin-1ß and cyclooxygenase-2 concentrations in the P78 rat striatum. These results indicate that neonatal systemic LPS exposure produces a persistent dopaminergic lesion leading to a long-lasting change in the brain reward system as indicated by the enhanced METH-induced behavioral sensitization and reinstated behavioral sensitization later in life. These findings indicate that early-life brain inflammation may enhance susceptibility to drug addiction development later in life, which provides new insights for developing potential therapeutic treatments for drug addiction.