Lymphocytes in autoimmune encephalitis: Pathogenesis and therapeutic target.

Autoimmune encephalitis (AE) is an inflammatory disease of the central nervous system characterized by the production of various autoimmune antibodies targeting neuronal proteins. The pathogenesis of AE remains elusive. Accumulating evidence suggests that lymphocytes, particularly B and T lymphocytes, play an integral role in the development of AE. In the last two decades, autoimmune neural antibodies have taken center stage in diagnosing AE. Recently, increasing evidence has highlighted the importance of T lymphocytes in the onset of AE. CD4+ T cells are thought to influence disease progression by secreting associated cytokines, whereas CD8+ T cells exert a cytotoxic role, causing irreversible damage to neurons mainly in patients with paraneoplastic AE. Conventionally, the first-line treatments for AE include intravenous steroids, intravenous immunoglobulin, and plasma exchange to remove pathogenic autoantibodies. However, a minority of patients are insensitive to conventional first-line treatment protocols and suffer from disease relapse, a condition referred to as refractory AE. In recent years, new treatments, such as rituximab or CAAR-T, which target pathogenic lymphocytes in patients with AE, have offered new therapeutic options for refractory AE. This review aims to describe the current knowledge about the function of B and T lymphocytes in the pathophysiology of AE and to summarize and update the immunotherapy options for treating this disease.

New insights into neuropathology and pathogenesis of autoimmune glial fibrillary acidic protein meningoencephalomyelitis.

Anti-glial fibrillary acidic protein (GFAP) meningoencephalomyelitis (autoimmune GFAP astrocytopathy) is a new autoimmune central nervous system (CNS) disease diagnosable by the presence of anti-GFAP autoantibodies in the cerebrospinal fluid and presents as meningoencephalomyelitis in the majority of patients. Only few neuropathological reports are available and little is known about the pathogenic mechanisms. We performed a histopathological study of two autopsies and nine CNS biopsies of patients with anti-GFAP autoantibodies and found predominantly a lymphocytic and in one autopsy case a granulomatous inflammatory phenotype. Inflammatory infiltrates were composed of B and T cells, including tissue-resident memory T cells. Although obvious astrocytic damage was absent in the GFAP-staining, we found cytotoxic T cell-mediated reactions reflected by the presence of CD8+/perforin+/granzyme A/B+ cells, polarized towards astrocytes. MHC-class-I was upregulated in reactive astrocytes of all biopsies and two autopsies but not in healthy controls. Importantly, we observed a prominent immunoreactivity of astrocytes with the complement factor C4d. Finally, we provided insight into an early phase of GFAP autoimmunity in an autopsy of a pug dog encephalitis that was characterized by marked meningoencephalitis with selective astrocytic damage with loss of GFAP and AQP4 in the lesions.Our histopathological findings indicate that a cytotoxic T cell-mediated immune reaction is present in GFAP autoimmunity. Complement C4d deposition on astrocytes could either represent the cause or consequence of astrocytic reactivity. Selective astrocytic damage is prominent in the early phase of GFAP autoimmunity in a canine autopsy case, but mild or absent in subacute and chronic stages in human disease, probably due to the high regeneration potential of astrocytes. The lymphocytic and granulomatous phenotypes might reflect different stages of lesion development or patient-specific modifications of the immune response. Future studies will be necessary to investigate possible implications of pathological subtypes for clinical disease course and therapeutic strategies.

Autoimmune and inflammatory neurological disorders in the intensive care unit.

PURPOSE OF REVIEW: The present review summarizes the diagnostic approach to autoimmune encephalitis (AE) in the intensive care unit (ICU) and provides practical guidance on therapeutic management. RECENT FINDINGS: Autoimmune encephalitis represents a group of immune-mediated brain diseases associated with antibodies that are pathogenic against central nervous system proteins. Recent findings suggests that the diagnosis of AE requires a multidisciplinary approach including appropriate recognition of common clinical syndromes, brain imaging and electroencephalography to confirm focal pathology, and cerebrospinal fluid and serum tests to rule out common brain infections, and to detect autoantibodies. ICU admission may be necessary at AE onset because of altered mental status, refractory seizures, and/or dysautonomia. Early management in ICU includes prompt initiation of immunotherapy, detection and treatment of seizures, and supportive care with neuromonitoring. In parallel, screening for neoplasm should be systematically performed. Despite severe presentation, epidemiological studies suggest that functional recovery is likely under appropriate therapy, even after prolonged ICU stays. CONCLUSION: AE and related disorders are increasingly recognized in the ICU population. Critical care physicians should be aware of these conditions and consider them early in the differential diagnosis of patients presenting with unexplained encephalopathy. A multidisciplinary approach is mandatory for diagnosis, ICU management, specific therapy, and prognostication.

What is autoimmune encephalitis-associated epilepsy? Proposal of a practical definition.

Seizures resulting from cerebral autoimmunity are either acutely symptomatic in the context of autoimmune encephalitis (AIE) with neural surface antibodies, or they are indicative of an enduring predisposition to seizures, that is, epilepsy. Here, we propose a practical definition for autoimmune encephalitis-associated epilepsy (AEAE): Seizures associated with antibodies against glutamic acid decarboxylase, paraneoplastic syndromes, or Rasmussen encephalitis are classified as AEAE. AEAE secondary to AIE with antibodies against the N-methyl-D-aspartate receptor, leucine-rich glioma inactivated protein 1, contactin-associated protein-2, or γ-aminobutyric acid-B receptor can be diagnosed if the following criteria are met: seizures persist for at least 2 years after immunotherapy initiation; no signs of encephalitis on magnetic resonance imaging and no fluorodeoxyglucose positron emission tomography hypermetabolism; normal cerebrospinal fluid cell count; and a substantial decrease in antibody titers. This classification corresponds to different disease mechanisms. While AIE results from the pathogenic effects of neural antibodies, AEAE is probably the consequence of encephalitis-related tissue damage and thereby mainly structurally mediated. The distinction between AIE and AEAE also has practical consequences: In AIE, immunotherapy is usually highly beneficial, whereas anti-seizure medication has little effect. In AEAE, immunotherapy is less promising and the usual anti-seizure interventions are preferable. In addition, the diagnosis of AEAE has social consequences in terms of driving and professional limitations.

An updated review of pediatric autoimmune neuropsychiatric disorders associated with Streptococcus/pediatric acute-onset neuropsychiatric syndrome, also known as idiopathic autoimmune encephalitis: What the allergist should know.

BACKGROUND: Pediatric acute-onset neuropsychiatric syndrome, further subcategorized as pediatric autoimmune neuropsychiatric disorders associated with streptococcus, is a form of idiopathic autoimmune encephalitis (IAE). Poststreptococcal autoimmunity seen in Idiopathic autoimmune encephalitis manifests as various neuropsychiatric symptoms such as obsessive rituals, tics, anxiety, depression, and many others. Idiopathic autoimmune encephalitis has clinically heterogeneous phenotypes that make accurate diagnosing difficult, although diagnostic testing such as the Cunningham Panel increases the likelihood of finding effective treatments. Current recommended treatments include psychiatric medication, behavioral intervention, antibiotics, anti-inflammatory therapy, and immunomodulating therapy. OBJECTIVE: To provide an updated review on the diagnosis, management, and treatment of pediatric autoimmune neuropsychiatric disorder associated with streptococcus and pediatric autoimmune neuropsychiatric syndrome, also referred to as IAE. RESULTS: Information from 47 sources was used to outline current knowledge of IAE pathophysiology, clinical manifestations, and epidemiology, and to outline diagnostic recommendations and current treatment guidelines. Gaps in knowledge, in addition to current controversy, were also outlined to provide a thorough background of this condition and future needs for IAE research. CONCLUSION: Owing to the complexity and variability in ways patients with IAE may present to the allergist/immunologist office, an interdisciplinary approach is imperative to provide patients with the best medical care. Still, more research is needed to further elucidate the mechanism(s) and optimal treatment algorithm for IAE to facilitate broader recognition and acceptance of this condition by the medical community.

Clinical characteristics of Leucine-rich glioma-inactivated protein 1 antibody-mediated autoimmune encephalitis in a 6-year-old girl: case report and literature reviews.

BACKGROUND: Autoimmune encephalitis related to the leucine-rich glioma-inactivated protein 1(LGI1) antibody is the most prevalent in older adults, manifesting as seizures, faciobrachial dystonic seizures (FBDS), cognitive impairment, memory disturbance, hyponatremia and neuropsychiatric disorders. However the data pertaining to children affected by the disease is still limited. CASE PRESENTATION AND LITERATURE REVIEWS: This study presents a detailed report of a 6-year-old Chinese girl who experienced nose aches and faciobrachial dystonic seizures (FBDS). Electrolyte testing revealed that she had hyponatremia and brain MRI showed an abnormality in the left temporal pole. Additionally, anti-LGI1 antibodies were detected in both her serum (1:100) and CSF (1:30). The patient was treated with immunotherapy and symptom management, which proved effective. Furthermore, we provide a summary of 25 pediatric cases of anti-LGI1 encephalitis. Pediatric patients rarely exhibited FBDS and hyponatremia, and some cases presented with isolated syndromes. But the therapeutic outcomes of pediatric patients were generally good. CONCLUSIONS: In this report, we describe a patient who developed a rare symptom of nose aches possibly as one of symptoms of anti-LGI1 encephalitis, which highlights the possibility of atypical symptoms in children that may be misdiagnosed. Reviewing the literature, the clinical features differed between pediatric and adult cases. Therefore, it is crucial to collect and analyze data from more cases to promote accurate diagnosis and timely treatment.

Facilities, selection, outcome measurement, and limitations of therapeutic plasma exchange for neuroimmunological disorders: The South East Asian survey study.

INTRODUCTION: Therapeutic plasma exchange (TPE) for neuroimmunological disorders has played an important role in the Southeast Asian region. This study investigates the challenges of performing TPE within the region. METHOD: A questionnaire-based survey was conducted and launched to 15 South East Asian Therapeutic Plasma Exchange Consortium (SEATPEC) members from seven countries in January 2021. It included demographics, TPE techniques, indications, challenges, timing, outcome measurement, and access to laboratory testing in each local center. RESULTS: A total of 15 neurologists from 12 participating centers were included. They usually perform five sessions of TPE (100.0%), with 1 to 1.5 plasma volume (93.3%), and exchanges via the central catheter (100.0%). Acute relapses of neuromyelitis optica spectrum disorder and myasthenia gravis are the most common indications. They used a combination of normal saline and 5% albumin (60.0%) as replacement fluid. Most (66.7%) used TPE as an add-on treatment in steroid-refractory cases or as first-line treatment for severe attacks. They suggested assessing the TPE efficacy of TPE by the interval to the next attack, post-TPE relapse rates, and TPE-related complications. The major challenges within our region are expense, reimbursibility, and access to TPE. CONCLUSION: Although countrywise differences exist, all share similarities regarding methods, indications, timing, obstacles, and challenges of TPE for neuroimmunological conditions. Regional collaboration will be essential to identify strategies to reduce these barriers to access to TPE in the future.

Parainfectious autoimmune encephalitis related to SARS-CoV-2 infection, presenting with catatonia.

OBJECTIVE: SARS-CoV-2 infection commonly affects both the central and peripheral nervous systems, resulting in a variety of neurological and psychiatric symptoms. Whereas the effects of SARS-CoV-2 on neuronal structures in the short and long-term are still controversial, neurological involvement secondary to SARS-CoV- 2 is heterogeneous in terms of clinical presentation, treatment response, and prognosis. METHOD: A case of autoimmune encephalitis developing after SARS-CoV-2 is described in this article. RESULTS: The patient was admitted to the clinic with classical signs of catatonia and encephalopathy. The emergence of neuropsychiatric problems after the relief of SARS-CoV-2 symptoms suggests that symptoms were primarily related to immune processes. This patient demonstrated a good clinical response to symptomatic catatonia treatment and immune-modulatory agents and recovered both physically and cognitively without sequelae. CONCLUSION: SARS-CoV-2 infection may involve encephalitic involvement and psychological symptoms (including catatonia) after the infection by triggering autoimmune pathways.

[Autoimmune encephalitis-Challenges and management in intensive medical care]. / Autoimmunenzephalitis ­ intensivmedizinische Herausforderungen und Management.

Despite relevant improvements in the diagnostics and treatment of autoimmune encephalitis (AE), severely affected patients still need treatment on the intensive care unit (ICU). Such complex disease states are sometimes difficult to bring under control and ICU complications have a negative influence on the outcome of treatment. A rapid diagnosis and timely initiation of immunotherapy are crucial to minimize ICU treatment and to avoid potentially severe complications. This article outlines the ICU treatment of autoimmune encephalitis and describes the most common challenges and complications of (neuro)intensive medical care and their management.

[Autoimmune encephalitis-An update]. / Autoimmunenzephalitis ­ ein Update.

Detection of autoantibodies against neurons and glia cells has brought about the early and specific diagnosis of autoimmune encephalitis in patients with variable neurological and psychiatric symptoms. Growing knowledge not only resulted in profound changes in treatment algorithms including immunotherapy but also in the understanding of disease mechanisms and etiological factors. The still increasing numbers of new autoantibodies calls for continuous updates on the state of the art in antibody diagnostics, frequencies of associated tumors and the clinical spectrum linked to each antibody, which can range from mood changes, cognitive impairment and epileptic seizures to abnormal movements, autonomic dysfunction and impaired levels of consciousness. This article summarizes the recent developments in the predominant clinical presentations of autoimmune encephalitis patients in imaging and cerebrospinal fluid diagnostics and also in prognostic markers, in the establishment of innovative immunotherapies, in the use of diagnostic pathways even before the results of the antibody tests are available and the understanding of the autoimmune etiology.

Multimodal Biomarkers Quantify Recovery in Autoimmune Autonomic Ganglionopathy.

OBJECTIVE: The objective of this study was to evaluate patients with ganglionic acetylcholine receptor antibody (gAChR-Ab) positive autoimmune autonomic ganglionopathy using a multimodal testing protocol to characterize their full clinical phenotype and explore biomarkers to quantify immunotherapy response. METHODS: We conducted a cohort study of 13 individuals (7 women, 21-69 years of age) with autonomic failure and gAChR-Ab >100 pM identified between 2005 and 2019. From 2018, all patients were longitudinally assessed with cardiovascular, pupillary, urinary, sudomotor, lacrimal and salivary testing, and Composite Autonomic Symptom Score (COMPASS-31) autonomic symptom questionnaires. The orthostatic intolerance ratio was calculated by dividing change in systolic blood pressure over time tolerated on head-up tilt. Eleven patients received immunotherapy. RESULTS: At first assessment, all 13 patients had cardiovascular and pupillary impairments, 7 of 8 had postganglionic sudomotor dysfunction, 9 of 11 had urinary retention and xeropthalmia, and 6 of 8 had xerostomia. After immunotherapy, there were significant improvements in orthostatic intolerance ratio (33.3 [17.8-61.3] to 5.2 [1.4-8.2], p = 0.007), heart rate response to deep breathing (1.5 [0.0-3.3] to 4.5 [3.0-6.3], p = 0.02), pupillary constriction to light (12.0 [5.5-18.0] to 19.0 [10.6-23.8]%, p = 0.02), saliva production (0.01 [0.01-0.05] to 0.08 [0.02-0.20] g/min, p = 0.03), and COMPASS-31 scores (52 to 17, p = 0.03). Orthostatic intolerance ratio correlated with autonomic symptoms at baseline (r = 0.841, p = 0.01) and following immunotherapy (r = 0.889, p = 0.02). Immunofluorescence analyses of skin samples from a patient 32 years after disease onset showed loss of nerve fibers supplying the dermal autonomic adnexa and epidermis, with clear improvements following immunotherapy. INTERPRETATION: Patients with autoimmune autonomic ganglionopathy demonstrated objective evidence of widespread sympathetic and parasympathetic autonomic failure, with significant improvements after immunotherapy. Quantitative autonomic biomarkers should be used to define initial deficits, guide therapeutic decisions, and document treatment response. ANN NEUROL 2021;89:753-768.

Pathophysiology and Clinical Management of Autoimmune Encephalitis-Associated Seizures.

Seizures are a very common manifestation of autoimmune encephalitis (AE), ranging from 33% to 100% depending on the antigen, most often accompanied by other clinical features such as behavioral changes, movement disorders, memory deficits, autoimmune disturbances, and altered levels of consciousness. Unusual seizure frequency, resistance to antiepileptic treatment, and often, definitive response to immunotherapy emphasize the importance for neurologists to consider the probable etiology of immune disorders. Studies on pathogenic mechanisms of autoantibodies have improved the understanding of different pathophysiologies and clinical characteristics of different AE groups. In encephalitis with antibodies to neuronal extracellular antigens, autoantibodies play a direct role in disease pathogenesis. They have access to target antigens and can potentially alter the structure and function of antigens but induce relatively little neuronal death. Prompt immunotherapy is usually very effective, and long-term antiepileptic treatment may not be needed. In contrast, in encephalitis with antibodies against intracellular antigens, autoantibodies may not be directly pathogenic but serve as tumor markers. These autoantibodies cannot reach intracellular target antigens and are considered to result from a T-cell-mediated immune response against antigens released by apoptotic tumor cells, which contain nerve tissue or express neuronal proteins. Neuronal loss is frequently described and predominantly induced through cytotoxic T-cell mechanisms. They often exhibit an inadequate response to immunotherapy and require early tumor treatment. Long-term antiepileptic treatment is usually needed. In conclusion, each neural autoantibody can specifically precipitate seizures. Early proper management of these cases may help prevent neurological deterioration and manage the occurrence of seizures. Consequently, confirmation of the presence of neuronal autoantibodies is strongly recommended even in patients with confirmed AE, as they are not only essential in achieving a good outcome but also may provide evidence for underlying neoplasia.

Immunoadsorption and plasma exchange-Efficient treatment options for neurological autoimmune diseases.

BACKGROUND: Therapeutic plasma exchange (TPE) and immunoadsorption (IA) are first or second line treatment options in patients with neurological autoimmune diseases, including multiple sclerosis, neuromyelitis optica spectrum disorders (NMSOD), chronic inflammatory demyelinating polyneuropathy, acute inflammatory demyelinating polyradiculoneuropathy (Guillain-Barré syndrome), and autoimmune encephalitis. METHODS: In this prospective randomized controlled monocentric study, we assessed safety and efficacy of therapy with IA or TPE in patients with neurological autoimmune diseases. Treatment response was assessed using various neurological scores as well by measuring immunoglobulin and cytokine concentrations. Clinical outcome was evaluated by application of specific scores for the underlying diseases. RESULTS: A total of 32 patients were analyzed. Among these, 19 patients were treated with TPE and 13 patients with IA. IA and TPE therapy showed a comparable significant treatment response. In patients with MS and NMOSD, mean EDSS before and after treatment showed a significant reduction after treatment with IA. We observed a significant reduction of the pro-inflammatory cytokines IL-12, lL-17, IL-6, INF-γ, and tumor necrosis factor alpha during IA treatment, whereas this reduction was not seen in patients treated with TPE. CONCLUSIONS: In summary, both IA and TPE were effective and safe procedures for treating neurological autoimmune diseases. However, there was a trend towards longer therapy response in patients treated with IA compared to TPE, possibly related to a reduction in plasma levels of pro-inflammatory cytokines seen only in the IA-treated group.

Autonomic neuropathies.

Autonomic neuropathies represent a complex group of disorders that preferentially target autonomic fibers and can be classified as either acute/subacute or chronic in onset. Acute-onset autonomic neuropathies manifest with such conditions as paraneoplastic syndromes, Guillain-Barre syndrome, Sjögren syndrome, infection, or toxins/chemotherapy. When the presentation is acute, immune-mediated, and without a secondary cause, autoimmune autonomic ganglionopathy is likely, and should be considered for immunotherapy. Of the chronic-onset forms, diabetes is the most widespread and disabling, with autonomic impairment portending increased mortality and cardiac wall remodeling risk. Acquired light chain (AL) and transthyretin (TTR) amyloidosis represent two other key etiologies, with TTR amyloidosis now amenable to newly-approved gene-modifying therapies. The COMPASS-31 questionnaire is a validated outcome measure that can be used to monitor autonomic severity and track treatment response. Symptomatic treatments targeting orthostatic hypotension, among other symptoms, should be individualized and complement disease-modifying therapy, when possible.

Cells to the Rescue: Emerging Cell-Based Treatment Approaches for NMOSD and MOGAD.

Cell-based therapies are gaining momentum as promising treatments for rare neurological autoimmune diseases, including neuromyelitis optica spectrum disorders and myelin oligodendrocyte glycoprotein antibody-associated disease. The development of targeted cell therapies is hampered by the lack of adequate animal models that mirror the human disease. Most cell-based treatments, including HSCT, CAR-T cell, tolerogenic dendritic cell and mesenchymal stem cell treatment have entered early stage clinical trials or have been used as rescue treatment in treatment-refractory cases. The development of antigen-specific cell-based immunotherapies for autoimmune diseases is slowed down by the rarity of the diseases, the lack of surrogate outcomes and biomarkers that are able to predict long-term outcomes and/or therapy effectiveness as well as challenges in the manufacturing of cellular products. These challenges are likely to be overcome by future research.

Complex syndromes of chronic pain, fatigue and cognitive impairment linked to autoimmune dysautonomia and small fiber neuropathy.

Chronic fatigue syndrome, postural orthostatic tachycardia syndrome, complex regional pain syndrome and silicone implant incompatibility syndrome are a subject of debate among clinicians and researchers. Both the pathogenesis and treatment of these disorders require further study. In this paper we summarize the evidence regarding the role of autoimmunity in these four syndromes with respect to immunogenetics, autoimmune co-morbidities, alteration in immune cell subsets, production of autoantibodies and presentation in animal models. These syndromes could be incorporated in a new concept of autoimmune neurosensory dysautonomia with the common denominators of autoantibodies against G-protein coupled receptors and small fiber neuropathy. Sjogren's syndrome, which is a classical autoimmune disease, could serve as a disease model, illustrating the concept. Development of this concept aims to identify an apparently autoimmune subgroup of the disputable disorders, addressed in the review, which may most benefit from the immunotherapy.

Management challenges for chronic dysimmune neuropathies during the COVID-19 pandemic.

Since March 2020, the COVID-19 pandemic has led to the need to re-think the delivery of services to patients with chronic dysimmune neuropathies. Telephone/video consultations have become widespread but have compounded concerns about objective evaluation. Therapeutic decisions need, more than ever before, to be considered in the best interests of both patients, and society, while not denying function-preserving/restoring treatment. Immunoglobulin therapy and plasma exchange, for those treated outside of the home, expose patients to the hazards of hospital or outpatient infusion centers. Steroid therapy initiation and continuation pose increased infectious risk. Immunosuppressant therapy similarly becomes highly problematic, with the risks of treatment continuation enhanced by uncertainties regarding duration of the pandemic. The required processes necessitate considerable time and effort especially as resources and staff are re-deployed to face the pandemic, but are essential for protecting this group of patients and as an integral part of wider public health actions.

Immunologic Treatments of Seizures and Status Epilepticus.

An autoimmune etiology for seizures, epilepsy, and status epilepticus is becoming increasingly recognized. The role of autoimmunity in epilepsy has been highlighted in the literature and the International League Against Epilepsy now recognizes autoimmune epilepsy as a distinct entity. An appropriate and thorough work-up of all new-onset seizures and status epilepticus is paramount in determining the likely efficacy of immunotherapeutic agents in treating seizures and status epilepticus. Criteria for the clinical diagnosis of autoimmune mediated epilepsy and encephalitis have been published by expert consensus and validated models to predict response to immunotherapy exist. These guidelines should guide clinicians about when to promptly start immunotherapy. Immunotherapy has been shown to improve outcomes and may reduce relapse rates in autoimmune encephalitis. Treatment algorithms with immunotherapeutic agents have been established by expert opinion and multiple observational retrospective trials in the past 10 years. However, future prospective randomized controlled trials are still needed to better understand the optimal regimen, dosing schedule, and duration of treatment with immunotherapeutic agents.

Understanding Pediatric Neuroimmune Disorder Conflicts: A Neuroradiologic Approach in the Molecular Era.

Neuroimmune disorders in children are a complex group of inflammatory conditions of the central nervous system with diverse pathophysiologic mechanisms and clinical manifestations. Improvements in antibody analysis, genetics, neuroradiology, and different clinical phenotyping have expanded knowledge of the different neuroimmune disorders. The authors focus on pediatric-onset myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease, which is a new entity in the spectrum of inflammatory demyelinating diseases, distinct from both multiple sclerosis (MS) and anti-aquaporin-4 (AQP4) antibody neuromyelitis optica spectrum disorders (NMOSDs). The authors review the importance of an optimized antibody-detection assay, the frequency of MOG antibodies in children with acquired demyelinating syndrome (ADS), the disease course, the clinical spectrum, proposed diagnostic criteria, and neuroimaging of MOG antibody-associated disease. Also, they outline differential diagnosis from other neuroimmune disorders in children according to the putative primary immune mechanism. Finally, they recommend a diagnostic algorithm for the first manifestation of ADS or relapsing ADS that leads to four demyelinating syndromes: MOG antibody-associated disease, AQP4 antibody NMOSDs, MS, and seronegative relapsing ADS. This diagnostic approach provides a framework for the strategic role of neuroradiology in diagnosis of ADS and decision making, to optimize patient care and treatment outcome in concert with clinicians. Online supplemental material is available for this article. ©RSNA, 2020.

Treatments in Aicardi-Goutières syndrome.

Comprehensive reviews of the clinical characteristics and pathogenesis of Aicardi-Goutières syndrome (AGS), particularly its contextualization within a putative type I interferonopathy framework, already exist. However, recent reports of attempts at treatment suggest that an assessment of the field from a therapeutic perspective is warranted at this time. Here, we briefly summarize the neurological phenotypes associated with mutations in the seven genes so far associated with AGS, rehearse current knowledge of the pathology as it relates to possible treatment approaches, critically appraise the potential utility of therapies, and discuss the challenges in assessing clinical efficacy. WHAT THIS PAPER ADDS: Progress in understanding AGS disease pathogenesis has led to the first attempts at targeted treatment. Further rational therapies are expected to become available in the short- to medium-term.