MOG Antibody Disease: Nuances in Presentation, Diagnosis, and Management.

PURPOSE OF REVIEW: Myelin oligodendrocyte glycoprotein antibody disease (MOGAD) is a distinct neuroinflammatory condition characterized by attacks of optic neuritis, transverse myelitis, and other demyelinating events. Though it can mimic multiple sclerosis and neuromyelitis optica spectrum disorder, distinct clinical and radiologic features which can discriminate these conditions are now recognized. This review highlights recent advances in our understanding of clinical manifestations, diagnosis, and treatment of MOGAD. RECENT FINDINGS: Studies have identified subtleties of common clinical attacks and identified more rare phenotypes, including cerebral cortical encephalitis, which have broadened our understanding of the clinicoradiologic spectrum of MOGAD and culminated in the recent publication of proposed diagnostic criteria with a familiar construction to those diagnosing other neuroinflammatory conditions. These criteria, in combination with advances in antibody testing, should simultaneously lead to wider recognition and reduced incidence of misdiagnosis. In addition, recent observational studies have raised new questions about when to treat MOGAD chronically, and with which agent. MOGAD pathophysiology informs some of the relatively unique clinical and radiologic features which have come to define this condition, and similarly has implications for diagnosis and management. Further prospective studies and the first clinical trials of therapeutic options will answer several remaining questions about the peculiarities of this condition.

Moyamoya disease in a 5-year child secondary to MOG antibody-positive cerebral cortical encephalitis.

A 5-year-old girl presented with complaints of fever, left-sided hemiparesis, and left upper motor neuron facial nerve palsy following oral polio booster dose vaccination. She had a past history of fever with altered sensorium with complete resolution at 3 years of age. Cerebrospinal fluid evaluation and stool examination were inconclusive. MRI with MRA showed T2 hyperintensities of the right fronto-temporo-parietal cortex with diffusion restriction and occlusion of bilateral internal carotid arteries and collateral formation suggestive of Moyamoya disease with cerebral cortical encephalitis. Evaluation of encephalitis revealed positivity for anti-myelin oligodendrocyte (MOG) antibodies. She showed a good response to intravenous immunoglobulin and pulse steroids with resolution of encephalitis and facial nerve palsy and improvement in the power of the left side of the body. We presume that the Moyamoya disease in this case is possibly secondary to myelin oligodendrocyte antibody-associated disease.

Clinical and radiological spectrum of anti-myelin oligodendrocyte glycoprotein (MOG) antibody encephalitis: single-center observational study.

OBJECTIVE: The objective was to describe the clinical presentations, radiologic features, and outcomes of patients with autoimmune encephalitis associated with myelin oligodendrocyte glycoprotein antibody (MOG). BACKGROUND: During the past decade, the spectrum of the myelin oligodendrocyte glycoprotein antibody-associated diseases (MOGAD) has expanded. Recently, patients with MOG antibody encephalitis (MOG-E) who do not fulfill the criteria for ADEM have been reported. In this study, we aimed to describe the spectrum of MOG-E. METHODS: Sixty-four patients with MOGAD were screened for encephalitis-like presentation. We collected the clinical, radiological, laboratory, and outcome data of the patients who presented with encephalitis and compared it with the non-encephalitis group. RESULTS: We identified sixteen patients (nine males and seven females) with MOG-E. The median age of the encephalitis population was significantly lower than the non-encephalitis group (14.5 years (11.75-18) vs. 28 years (19.75-42), p = 0.0004). Twelve out of sixteen patients (75%) had fever at the time of encephalitis. Headache and seizure were present in 9/16 (56.2%) and 7/16 (43.75%) patients, respectively. FLAIR cortical hyperintensity was present in 10/16 (62.5%) patients. Supratentorial deep gray nuclei were involved in 10/16 (62.5%) patients. Three patients had tumefactive demyelination, and one patient had a leukodystrophy-like lesion. Twelve of 16 (75%) patients had a good clinical outcome. Patient with leukodystrophy pattern and other with generalized CNS atrophy showed a chronic progressive course. CONCLUSION: MOG-E can have heterogeneous radiological presentations. FLAIR cortical hyperintensity, tumefactive demyelination, and leukodystrophy-like presentations are novel radiological presentations associated with MOGAD. Though majority of MOG-E have a good clinical outcome, few patients can have chronic progressive disease even on immunosuppressive therapy.

Unilateral cerebral cortical encephalitis with epilepsy: a possible special phenotype of MOG antibody-associated disorders.

Myelin oligodendrocyte glycoprotein (MOG) antibody-related encephalomyelitis is an increasingly recognized entity with heterogeneity in phenotype. Among all clinical phenotypes, encephalitis restricted to cerebral cortex might be most easily ignored and under-estimated type. Here, we described two cases of cerebral cortical encephalitis with MOG seropositivity to facilitate the awareness of the manifestations of the disease. In case 1, the patient presented with headaches and fevers turned out to have elevated CSF cells and cerebral cortical FLAIR hyperintense lesions in brain MRI. He was treated as intracranial infection during his first and second admission and fully resolved when discharged. During the patient's third admission, the patient experienced a seizure, and we found cerebral cortical FLAIR hyperintensity again and MOG antibody was positive in the serum. Therefore, we considered the patient suffered from MOG antibody encephalitis. In case 2, the patient also had headache, fever, and experienced a seizure. MOG antibody was positive in the serum and brain MRI showed cortical hyperintense lesions. Both the patients were young man, response well to corticosteroids and recovered completely. The two cases suggested that encephalitis, especially benign recurrent unilateral cerebral cortical encephalitis with epilepsy, might be a special phenotype of MOG antibody-associated disorders.

[Absence of cortical lesions after the first seizure in a patient with anti-myelin oligodendrocyte glycoprotein-associated cortical encephalitis].

A 31-year-old man developed headache and generalized convulsions. At the time of the first seizure, there was no distinct MRI abnormality. He was admitted to the hospital with repeated seizures, left-sided hemiparesis, and left-sided neglect. He had a slight fever, elevated cerebrospinal fluid (CSF) pressure, and increased CSF cell count with predominance of mononuclear cells. A repeat MRI scan on day 8 after the recurrent seizure showed cortical edema in the right cerebral hemisphere on fluid-attenuated inversion recovery (FLAIR), abnormal high signal on DWI, and decreased apparent diffusion coefficient. The patient was diagnosed with aseptic meningoencephalitis and treated with antiviral drugs and methylprednisolone pulse therapy. Serum anti-myelin oligodendrocyte glycoprotein (MOG) antibody was subsequently detected, and prednisolone was added to treat the FLAIR-hyperintense lesions in anti-MOG antibody associated encephalitis with seizures (FLAMES). It is important to identify the clinical picture and typical images of FLAMES to allow early treatment.

Two case reports and a systematic review of the literature on adult cerebral cortical encephalitis with anti-myelin oligodendrocyte glycoprotein antibody.

Background and purpose: Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) has gained recognition in recent years as an immune-mediated inflammatory demyelinating disease of the central nervous system. The clinical features and prognosis of MOGAD adult cerebral cortical encephalitis (adult CCE) have not been fully elucidated. This study aims to further characterize the clinical symptoms, magnetic resonance imaging (MRI) findings, and prognosis of CCE with anti-MOG antibody. Methods: We present two adult cases of CCE with anti-MOG antibody and summarize the clinical symptoms, magnetic resonance imaging (MRI) findings, and prognosis of this phenotype as per a completed systematic review of the literature. Results: We found a total of 39 cases of MOGAD adult CCE (36% females; average age of onset of 29 years). Among them, 85% had seizure, 82% had headache, 64% had cortical symptoms, 64% had fever, 54% had changes of consciousness, and 38% had ocular symptoms. All cases demonstrated cerebral cortical T2 fluid-attenuated inversion recovery (FLAIR) lesions on MRI. Of the 25 patients (with seizure or not) who had EEG reports, 76% of patients showed abnormal EEG. Cerebrospinal fluid (CSF) white blood cell count of 90% of patients and CSF total protein of 67% of patients were elevated. In 16 patients with available CSF cytology data, 11 (69%) had abnormal cytology findings with monocytic predominance. In the 15 cases for which MOG antibody IgG was tested in both serum and CSF, 14 (93%) demonstrated a higher positive MOG IgG titer in serum than CSF. The majority of patients were treated with immunosuppressive therapy (97% corticosteroids, 15% mycophenolate mofetil, 13% IVIg, 5% azathioprine, and 5% other). The majority of patients had a favorable prognosis after treatment, as exemplified by improved clinical symptoms and imaging. Two patients relapsed. Conclusions: The clinical presentation and prognosis of adult CCE remain less understood in comparison to more common MOGAD phenotypes. It is important to consider MOGAD as an underlying etiology for adult CCE, as early detection and immunotherapy may improve outcomes.

[Cingulate seizure as a clinical manifestation of anti-myelin oligodendrocyte glycoprotein antibody-positive cerebral cortical encephalitis of two cases].

We report two male patients who had a sensory seizure, which evolved into a focal impaired awareness tonic seizure, and after that, focal to bilateral tonic-clonic seizure. The first case, a 20-year-old man had been treated with steroids for anti-myelin oligodendrocyte glycoprotein (MOG) antibody-positive optic neuritis. His seizure started with abnormal sensation in the little finger of the left hand, which spread to the left upper and then to the left lower limb. The seizure then evolved into tonic seizures of the upper and lower limbs and he finally lost awareness. The second case, a 19-year-old man experienced floating dizziness while walking, followed by numbness and a pain-like electrical shock in the right upper limb. The right arm somatosensory seizure evolved into a right upper and lower limb tonic seizure, which spread to the bilateral limbs, and finally he lost awareness. Symptoms of both patients improved after the treatment with steroids. Both patients shared a similar high-intensity FLAIR lesion in the posterior midcingulate cortex. Both patients were diagnosed with MOG antibody-positive cerebral cortical encephalitis because of a positive titer of anti-MOG antibody in the serum. Several reports showed involvement of the cingulate gyrus in MOG antibody-positive cerebral cortical encephalitis, but only a few reported seizure semiology in detail. The semiology reported here is consistent with that of cingulate epilepsy or the findings of electrical stimulation of the cingulate cortex, namely, somatosensory (electric shock or heat sensation), motor (tonic posture), and vestibular symptoms (dizziness). Cingulate seizures should be suspected when patients show somatosensory seizures or focal tonic seizures. MOG antibody-positive cerebral cortical encephalitis should be considered as one of the differential diagnoses when the young patient shows the unique symptoms of an acute symptomatic cingulate seizure.

Association of Myelin Oligodendrocyte Glycoprotein Antibody-associated Disease with Coronavirus Disease 2019 Vaccination and Infection: A Case Report of Cortical Encephalitis and Transverse Myelitis Relapse.

We herein report a case of myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) that occurred following coronavirus disease 2019 (COVID-19) vaccination and its subsequent relapse after COVID-19 infection. A 34-year-old woman developed cortical encephalitis in the right temporoparietal lobe one week after receiving the mRNA-1273 vaccine. The cerebrospinal fluid was positive for anti-MOG antibody. Her symptoms gradually improved after three courses of intravenous methylprednisolone therapy. Six months later, she experienced a relapse of transverse myelitis following COVID-19 infection. Despite treatment with plasma exchange, the patient remained paralyzed in both lower limbs. We herein review the relationship between MOGAD and COVID-19 vaccination/infection.

Unilateral Autoimmune Encephalitis: A Case Report on a Rare Manifestation of Myelin Oligodendrocyte Glycoprotein Antibody Disease.

Myelin oligodendrocyte glycoprotein (MOG)-associated disease (MOGAD) is a rare, antibody-mediated inflammatory demyelinating disorder of the central nervous system (CNS) that has varying phenotypes. FLAIR (fluid-attenuated inversion recovery)-hyperintense Lesions in Anti-MOG-associated Encephalitis with Seizures (FLAMES) is a much rarer manifestation of cortical encephalitis encountered in MOGAD. We report a rare case of a nine-year-old girl who presented with a drop in her academic performance and right-sided Epilepsia partialis continua. Magnetic resonance imaging (MRI) of the brain detected evidence for unilateral (left) cortical encephalitis with peri-ictal juxtacortical edema. An electroencephalogram revealed a hemi-generalized poly spike and wave discharges in the left hemisphere, several of which correlated with myoclonic jerks. The cerebrospinal fluid (CSF) analysis was normal. Autoimmune workup resulted in a positive serum MOG-immunoglobulin G (IgG), which confirmed the diagnosis of FLAMES. The child showed an excellent clinical response to intravenous methylprednisolone and intravenous immunoglobulins therapy.

Clinical analysis of adult MOG antibody-associated cortical encephalitis.

OBJECTIVE: To describe the clinical and neuroimaging features, treatment response and outcomes of adult myelin oligodendrocyte glycoprotein (MOG) antibody-associated cortical encephalitis. METHODS: In this retrospective study, adult patients fulling the criteria of encephalitis but not fulfilling those of ADEM and tested positive for serum MOG antibody were recruited from Xiangya Hospital, Central South University (2019-2021). Clinical symptoms, laboratory data, imaging, and outcomes were analyzed. RESULTS: Eleven MOG antibody-associated cortical encephalitis patients consisting of 4 female (36.4%) and 7 male (63.6%) were included with a median onset age of 27 years (ranging: 16-32 years). Fever (8/11), headache (9/11) and seizures (7/11) were the most common symptoms of adult MOG cortical encephalitis, and generalized seizure was the dominant seizure type (4/7). Increased intracranial pressure (5/10, median 280 mm H2O, ranging 240-380 mm H2O), CSF pleocytosis (5/10, median 48 cells/µL, ranging: 18-1800 cells/µL), and protein elevation (4/10, median 0.67 g/L, ranging: 0.46-1.92 g/L) were common. Serum MOG antibody was detected in all patients and the coexistence of CSF NMDAR antibody was found in one case. Imaging showed abnormal brain MRI in 10 patients (90.9%) and 10/10 had the cortical involvement. 8/10 had unilateral lesions while 2/10 had bilateral lesions. 2/10 had the juxta cortical white matter lesions and 2/10 had the corpus callosum lesions. No involvement of deep gray matter or other white matter structure was noted. 5/11 had leptomeningeal and/or lesional enhancements. 10/11 patients had favorable outcomes and 2/11 had clinical relapses with persisting MOG antibody positive during the median follow-up interval of 10 months (ranging: 3-23months). CONCLUSION: Atypical clinical features for demyelinating diseases including seizures, remarkably increased intracranial pressure, pleocytosis, and protein elevation are common in MOG cortical encephalitis. Involvement of the corpus callosum and cortex around the midline could be unique imaging features of MOG antibody-associated bilateral cortical encephalitis.

Clinical characteristic of myelin oligodendrocyte glycoprotein antibody associated cortical encephalitis in adults and outcomes following glucocorticoid therapy.

Objective: To describe the clinical and radiological features, as well as outcomes following glucocorticoid therapy and recurrence in adults suffering from cortical encephalitis associated with myelin oligodendrocyte glycoprotein (MOG) antibody. Methods: The clinical information of nine adult patients suffering from cortical encephalitis associated with MOG antibody admitted to the Affiliated Brain Hospital of Nanjing Medical University from 2020 to 2022 was systematically reviewed. The clinical symptoms, laboratory data, imaging results, outcomes following glucocorticoid therapy and recurrence were evaluated. Result: A total of 9 patients positive for MOG antibody and suffering from cortical encephalitis were included in our study (55.6% men, median age 29 years, 15-57 years). The most common clinical symptoms included headache (77.8%), fever (66.7%), and generalized seizures (55.6%). Some patients also experienced limb shaking (22.2%), leg numbness (22.2%), transient motor aphasia (11.1%), and vision loss (11.1%). The main features of cerebrospinal fluid () examination were increased intracranial pressure, pleocytosis, and elevated cerebrospinal fluid (CSF) protein. In addition, N-methyl-D-aspartate receptor (NMDAR) and MOG antibodies were found in the CSF of 3 patients, and NMDAR, MOG, and glial fibrillary acidic protein antibodies were found in the CSF of 1 patient. All patients were subjected to magnetic resonance imaging (MRI) and the images of eight of them showed T2 and/flair image hyperintense lesions, three showed meningeal or lesion enhancement and four showed white matter lesions, which were mostly located in the midline structures (75%). All patients received glucocorticoid therapy in the acute phase and in remission, and eight of them received an intravenous high dose of methylprednisolone, including one patient who received a simultaneous immunoglobulin therapy. One patient was treated with low-dose prednisolone tablets. Seven (77.8%) patients were wholly recovered at discharge, and 2 (22.2%) patients were left with slight symptoms. During the median 9-month follow-up (range: 2-36 months), 2 (22.2%) patients developed recurrence. Conclusion: The clinical manifestations of adult MOG antibody-associated cortical encephalitis were significantly different from those of the typical MOG antibody-associated disease (MOGAD). Patients in the acute phase of the disease were prone to show signs similar to central nervous system infection, requiring clinicians to have the ability to recognize the disease to avoid misdiagnosis. In addition, seizures were common in MOG antibody-related encephalitis, and the type of seizures was age-related. Brain MRI results showed that the distribution of cerebral cortex lesions was closely related to the classification of cortical encephalitis. Based on the patient's response to the treatment, glucocorticoid therapy was effective against MOG antibody-associated cortical encephalitis, which is consistent with the treatment response and clinical prognosis of MOGAD. Therefore, our opinion was that MOG antibody might be the "responsible antibody" in MOG antibody-associated cortical encephalitis, although further studies are needed to confirm this hypothesis.

A case of unilateral recurrent cerebral cortical encephalitis with anti-myelin oligodendrocyte glycoprotein antibodies.

Myelin oligodendrocyte glycoprotein (MOG)-antibody-associated disease (MOGAD) is an independent inflammatory demyelinating disease. A rare phenotype of MOGAD is cerebral cortical encephalitis (CCE). This case report presents unilateral recurrent cerebral cortical encephalitis (CCE) with positive anti-MOG antibodies from a 55 year old man who was admitted with headache, fever and aphasia. This case highlights the findings of hyperintense lesions in the cortex of the right temporal gyrus with slight swelling on T2 FLAIR and anti MOG antibodies in serum (1:20) and CSF (1:80) when the patient presented again to hospital after the initial improvement with IVIG and glucocorticoids. In addition, the patient was found to have atrophy of the whole brain, especially the right temporal lobe, after becoming symptom-free with glucocorticoids. In summary, anti-MOG-associated CCE can be diagnosed with headache, fever, and seizures associated with the presence of anti-MOG antibodies. Unilateral CCE is a special clinical feature of MOGAD and cerebral atrophy can be found. Steroid therapy remains to be the standard treatment.

Electroclinical features of seizures in myelin oligodendrocyte glycoprotein antibody-associated cerebral cortical encephalitis: A case report and literature review.

PURPOSE: Myelin oligodendrocyte glycoprotein (MOG) antibodies (Abs) are associated with various central nervous system demyelinating disorders. Recently, they were detected in cerebral cortical encephalitis (CCE), which often causes seizures. We performed a literature review to elucidate the electroclinical features of CCE. In addition to the published cases, we describe a new, illustrative case of MOG-Ab-associated CCE (MOG-CCE) with multifocal seizures documented by video electroencephalograph (EEG). METHODS: We searched PubMed with the keywords "[MOG] AND [encephalitis]" and reviewed relevant articles. The articles included reports of patients with CCE (as demonstrated by magnetic resonance imaging) and serum MOG Ab positivity. Cases were excluded if no epileptic seizures were reported or if details of the seizures were unavailable. RESULTS: Our literature review identified 34 patients with MOG-CCE. An analysis of these 34 cases and the new case showed that 20 patients were male (57.1%), and the median age at presentation was 23 years (range, 6 to 46 years). Focal to bilateral tonic-clonic seizure was the most common seizure type, followed by focal motor seizure in the face or an arm or leg. EEG findings were available for 26 patients. Interictal epileptiform discharges (IEDs) and ictal EEG patterns were seen in 10 (38.5%) and 5 (19.2%) patients, respectively. Focal EEG abnormalities, including slow waves and IEDs, were observed in the central, parietal, occipital, or posterior temporal region. CONCLUSION: MOG-CCE has distinctive electroclinical features that differ from those of other autoimmune encephalitides. Careful electroclinical analysis of seizures can be helpful for diagnosing MOG-CCE.

Meningo-cortical manifestations of myelin oligodendrocyte glycoprotein antibody-associated disease: Review of a novel clinico-radiographic spectrum.

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an inflammatory demyelinating disease that is distinct from multiple sclerosis. Initial manifestations of MOGAD that were reported in the literature included optic neuritis, myelitis, brainstem demyelination and encephalitis, with emphasis placed on acute disseminated encephalomyelitis (ADEM) as the primary encephalitic presentation. In 2017, however, Ogawa et al. described four patients with seizures, unilateral cortical hyperintensities on brain magnetic resonance imaging T2-fluid-attenuated inversion recovery sequences, and anti-MOG positivity, indicating a potentially novel form of encephalitis in MOGAD. In 2019, we systematically reviewed the literature to better characterize this unique syndrome, which we referred to as unilateral cortical FLAIR-hyperintense Lesions in Anti-MOG-associated Encephalitis with Seizures (FLAMES). Subsequently, anti-MOG positivity in patients with a variety of cortical and meningeal disease presentations has been reported, indicating a broader spectrum of meningo-cortical manifestations in MOGAD that we review herein.

A case of bilateral limbic and recurrent unilateral cortical encephalitis with anti-myelin oligodendrocyte glycoprotein antibody positivity.

BACKGROUND: Anti-myelin oligodendrocyte glycoprotein (MOG) antibody can be detected not only in acute disseminated encephalomyelitis or optic neuritis but also in limbic or cortical encephalitis. However, no previous reports have demonstrated a relapsing case of these two types of encephalitis. CASE REPORT: An 11-year-old girl presented with fever, headache, abnormal behavior, focal impaired awareness seizures (FIAS) on the left side, and MRI hyperintensities in the bilateral amygdala, hippocampus, and right posterior temporal cortex. The symptoms were alleviated with two courses of intravenous methylprednisolone (IVMP) and one course of immunoglobulin. At 16 years of age, the patient returned with left-sided headache and MRI hyperintensities in the left temporal, parietal, and insular cortices, which improved after 3 courses of IVMP. Oral prednisolone (PSL) was tapered over 6 months, when FIAS reappeared on the right side of the body. MRI showed recurrence in the same regions as in the second episode. She received 3 courses of IVMP, followed by gradually tapered PSL without relapse for 1.5 year. Anti-MOG antibodies were positive in both serum and the cerebrospinal fluid prior to treatment in all three episodes. CONCLUSION: Our results revealed that anti-MOG antibody-related bilateral limbic and unilateral cortical encephalitis can manifest with a variety of phenotypes over time in the same patient.

[An 11 year old woman with myelin-oligodendrocyte glycoprotein antibody showing various phenotypes of central nervous system disorders in one year].

An 11-year-old woman with myelin-oligodendrocyte glycoprotein (MOG) antibody developed cortical encephalitis twice, followed by acute disseminated encephalomyelitis (ADEM) and optic neuritis in one year. Although optic neuritis was refractory after corticosteroid therapy, plasma exchange was effective and complete remission was achieved. We considered that episodes of cortical encephalitis, ADEM and optic neuritis occurred in the present patient can be included in MOG IgG-associated disorders. Also, we recommend plasma exchange for refractory MOG IgG-associated optic neuritis, even in pediatric patient.

[Anti-myelin oligodendrocyte glycoprotein antibody-positive unilateral cerebral cortical encephalitis occurring first as general convulsion after meningitis symptoms and second after headache].

The case was a 30-year-old man. He had generalized convulsion after preceding meningitis symptoms and transferred to our emergency department. He was tentatively diagnosed with meningoencephalitis and Todd paralysis based on elevation of cell counts in cerebrospinal fluid and abnormal high signals in the right cerebral cortex on brain FLAIR-MRI, and admitted on the same day. After admission, treatment with antibiotics, dexamethasone, antiviral drug and anticonvulsants was started. Both his clinical symptoms and findings on MRI improved steadily, and then he was discharged on day 19. Subsequently, headache exacerbated again and an additional examination for his serum sample taken on first admission day revealed presence of anti myelin oligodendrocyte glycoprotein (MOG)-antibody, resulting in his diagnosis of anti-MOG antibody unilateral cerebral cortical encephalitis (MOG-UCCE) on day 42. Rehospitalization was planned for introduction of steroid therapy, but generalized convulsion recurred on day 44 and he was hospitalized again. MRI image revealed no FLAIR high signal and cerebrospinal fluid was almost normal, but his headache and mild hemiparesis and numbness on the left side deteriorated again. Therefore, he was treated with intravenous high dose methylprednisolone followed by oral steroids. His clinical symptoms gradually improved, and he was discharged with slight headache on day 71. After discharge, there has been no recurrence under continuation of low dose oral steroids for two years. This case shows the need to measure anti-MOG antibody and introduce steroid therapy in the early phase in a case of suspected MOG-UCCE in a young patient with meningoencephalitis accompanied by generalized convulsion and characteristic abnormal findings on FLAIR-MRI.

Autoimmune Encephalitis in Children.

Autoimmune encephalitis is a group of central nervous system (CNS) inflammatory disorders that most commonly affect young adults and children. These disorders are closely associated with antibodies against neuronal cell-surface proteins, receptors, and ion channels; however, some forms of the disorder have no known antibody at this time. In children, neurological manifestations such as seizure, movement disorders, and focal neurological deficits are more prominent at initial presentation than psychiatric or behavioral symptoms. When psychiatric symptoms do occur, they often manifest as temper tantrums, aggression, agitation, and rarely psychosis. Prompt diagnosis and early treatment can lead to improved outcomes and decreased relapses. First-line therapies include intravenous steroids, intravenous immunoglobulin, and plasmapheresis, whereas rituximab and cyclophosphamide are utilized for refractory or relapsing disease. This review highlights the different forms of this disorder, discusses approach to diagnosis and treatment, and reviews the outcome and prognosis of children diagnosed with different forms of autoimmune encephalitis.

MOG antibody-positive cerebral cortical encephalitis: Two case reports and literature review.

OBJECTIVE: To investigate the clinical and MRI features of myelin oligodendrocyte glycoprotein (MOG) antibody-positive cerebral cortical encephalitis. METHODS: To summarize the clinical manifestations, magnetic resonance imaging (MRI) features, and diagnosis and treatment of two children diagnosed with MOG antibody-positive cortical encephalitis in our hospital, and to analyze all of the literature on MOG antibody-positive associated cerebral cortical encephalitis published in the last 10 years. RESULTS: A total of 24 patients, 20 adults, and 4 children were included. The main symptoms of all observed patients were as follows: seizures 20/24 (83%), headache 18/24 (75%), fever 13/24 (54%), and increased cell number in cerebrospinal fluid 22/24 (92%). The main radiological sign was enhanced FLAIR signal in cortical 24/24 (100%), including enhanced fluid-attenuated inversion recovery (FLAIR) signal in unilateral cortical 20/24 (83%). CONCLUSIONS: The clinical manifestations of MOG antibody-positive cerebral cortical encephalitis are complex and varied, and long-term follow-up is needed to clarify the prognosis and recurrence, providing reference for the clinical treatment.

Case Report: Four Cases of Cortical/Brainstem Encephalitis Positive for Myelin Oligodendrocyte Glycoprotein Immunoglobulin G.

AIM: Despite a significant improvement in the number of studies on myelin oligodendrocyte glycoprotein (MOG)-immunoglobulin G (IgG)-associated disorder (MOGAD) over the past few years, MOG-IgG-associated cortical/brainstem encephalitis remains a relatively uncommon and less-reported presentation among the MOGAD spectrum. This study aimed to report the clinical course, imaging features, and therapeutic response of MOG-IgG-associated cortical/brainstem encephalitis. METHODS: Data of four patients who suffered from cortical encephalitis with epileptic seizures and/or brainstem encephalitis during the course of the disease were retrospectively collected and analyzed. RESULTS: In this study, three male patients and one female patient, with a median age of onset of 21 years (ranging 20-51 years) were enrolled. An epileptic seizure was the main symptom of cortical encephalitis in these patients, while the manifestations of brainstem encephalitis were diverse. Cranial MRI demonstrated abnormal signals in unilateral or bilateral cortical or brainstem. Cerebrospinal fluid studies showed normal or mildly elevated leukocyte counts and protein levels, and a cell-based assay detected positive MOG-IgG in the serum of all patients. Two patients were misdiagnosed at the first attack, and both experienced a relapse. All of them accepted the first-line immunotherapy after a confirmed diagnosis and had a good outcome. CONCLUSION: Early suspicion of MOG-IgG-associated encephalitis is necessary for any patient with sudden onset of seizures or symptoms of brainstem damage, especially with lesions on unilateral/bilateral cortical or brainstem on brain MRI.