Autoimmune diseases and cancers overlapping with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD): A systematic review

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.

Protocol of a prospective multicenter study on comorbidity impact on multiple sclerosis and antibody-mediated diseases of the central nervous system (COMMIT)

Comorbidities in patients with multiple sclerosis (MS) and antibody-mediated diseases of the central nervous system (CNS) including neuromyelitis optica spectrum disorder (NMOSD), and myelin oligodendrocyte glycoprotein (MOG)-antibody-associated disease (MOGAD) are common and may influence the course of their neurological disease. Comorbidity may contribute to neuronal injury and therefore limit recovery from attacks, accelerate disease progression, and increase disability. This study aims to explore the impact of comorbidity, particularly vascular comorbidity, and related risk factors on clinical and paraclinical parameters of MS, NMOSD and MOGAD. We propose COMMIT, a prospective multicenter study with longitudinal follow-up of patients with MS, NMOSD, and MOGAD, with or without comorbidities, as well as healthy subjects as controls. Subjects will be stratified by age, sex and ethnicity. In consecutive samples we will analyze levels of inflammation and neurodegeneration markers in both fluid and cellular compartments of the peripheral blood and cerebrospinal fluid (CSF) using multiple state-of-the-art technologies, including untargeted proteomics and targeted ultrasensitive ELISA assays and quantitative reverse transcription polymerase chain reaction (RT-qPCR) as well as high-dimensional single-cell technologies i.e., mass cytometry and single-cell RNA sequencing. Algorithm-based data analyses will be used to unravel the relationship between these markers, optical coherence tomography (OCT) and magnetic resonance imaging (MRI), and clinical outcomes including frequency and severity of relapses, long-term disability, and quality of life. The goal is to evaluate the impact of comorbidities on MS, NMOSD, and MOGAD which may lead to development of treatment approaches to improve outcomes of inflammatory demyelinating diseases of the CNS.

MOG Antibody-Associated Disease in the Setting of Metastatic Melanoma Complicated by Immune Checkpoint Inhibitor Use

OBJECTIVES

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an autoimmune demyelinating disease rarely associated with malignancy. We report the clinical, MRI, immunopathology, and treatment response in a person with MOGAD and melanoma.

METHODS

This is a case report of a person with a multidisciplinary evaluation at a tertiary referral center.

RESULTS

A 52-year-old man presented with progressive encephalomyelitis that led to identification of metastatic melanoma. Investigations revealed positive MOG-IgG at high titers in serum (1:1,000; normal, <1:20) and CSF (1:4,096; normal, <1:2). MRI demonstrated multifocal T2 lesions with enhancement in the brain and spine. Brain biopsy showed demyelination and inflammation. MOG immunostaining was not present in the tumor tissue. He initially improved with methylprednisolone, plasmapheresis, prolonged oral steroid taper, and cancer-directed treatment with BRAF and MEK 1/2 inhibitors, but then developed bilateral optic neuritis. IV immunoglobulin (IVIG) was initiated. Five months later, he developed metastases and immune checkpoint inhibitor (ICI) treatment was started, which precipitated optic neuritis and myelitis despite IVIG and prednisone. Tocilizumab, an interleukin-6 receptor blocker, was started with excellent and sustained clinical and radiologic response.

DISCUSSION

This case revealed a presentation of MOGAD concurrent with melanoma without tumor MOG immunostaining. We highlight tocilizumab as a dual-purpose treatment of MOGAD and the neurologic immune-related adverse effect of ICI.

MOG antibody-associated optic neuritis

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is a demyelinating disorder, distinct from multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD). MOGAD most frequently presents with optic neuritis (MOG-ON), often with characteristic clinical and radiological features. Bilateral involvement, disc swelling clinically and radiologically, and longitudinally extensive optic nerve hyperintensity with associated optic perineuritis on MRI are key characteristics that can help distinguish MOG-ON from optic neuritis due to other aetiologies. The detection of serum MOG immunoglobulin G utilising a live cell-based assay in a patient with a compatible clinical phenotype is highly specific for the diagnosis of MOGAD. This review will highlight the key clinical and radiological features which expedite diagnosis, as well as ancillary investigations such as visual fields, visual evoked potentials and cerebrospinal fluid analysis, which may be less discriminatory. Optical coherence tomography can identify optic nerve swelling acutely, and atrophy chronically, and may transpire to have utility as a diagnostic and prognostic biomarker. MOG-ON appears to be largely responsive to corticosteroids, which are often the mainstay of acute management. However, relapses are common in patients in whom follow-up is prolonged, often in the context of early or rapid corticosteroid tapering. Establishing optimal acute therapy, the role of maintenance steroid-sparing immunotherapy for long-term relapse prevention, and identifying predictors of relapsing disease remain key research priorities in MOG-ON.

Unravelling the Complexity of Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a rare autoimmune disorder characterized by recurrent episodes of demyelination affecting the central nervous system. The following case report showcases a thorough analysis of a 21-year-old female patient presenting with MOGAD, outlining her clinical presentation, diagnostic workup, treatment protocol, and long-term management outcomes. Through a multidisciplinary approach, we aim to augment the understanding of this complex neurological entity and steer optimal therapeutic interventions.

Immune-Mediated Myelopathies

OBJECTIVE

Immune-mediated myelopathies are conditions in which the immune system attacks the spinal cord. This article describes the distinguishing characteristics of immune-mediated myelopathies and treatment strategies for patients affected by these disorders.

LATEST DEVELOPMENTS

New biomarkers, such as aquaporin 4 and myelin oligodendrocyte glycoprotein antibodies, in the blood and spinal fluid have led to the identification of antigen-specific immune-mediated myelopathies and approved therapies to prevent disease progression.

ESSENTIAL POINTS

The first step in the diagnosis of an immune-mediated myelopathy is confirming that the immune system is the cause of the attack by excluding non-immune-mediated causes. The second step is to narrow the differential diagnosis based on objective biomarkers such as serology and MRI patterns. The third step is to treat the specific immune-mediated myelopathy by using evidence-based medicine.

Myelin oligodendrocyte glycoprotein antibody and N-methyl-d-aspartate receptor antibody overlapping syndrome: insights from the recent case reports

The overlapping of two or more types of neural autoantibodies in one patient has increasingly been documented in recent years. The coexistence of myelin oligodendrocyte glycoprotein (MOG) and N-methyl-d-aspartate receptor (NMDAR) antibodies is most common, which leads to a unique condition known as the MOG antibody and NMDAR antibody overlapping syndrome (MNOS). Here, we have reviewed the pathogenesis, clinical manifestations, paraclinical features, and treatment of MNOS. Forty-nine patients with MNOS were included in this study. They were young males with a median onset age of 23 years. No tumors were observed in the patients, and 24 of them reported prodromal symptoms. The most common clinical presentations were psychiatric symptoms (35/49) and seizures (25/49). Abnormalities on magnetic resonance imaging involved the brainstem (11/49), cerebellum (9/49), and parietal lobe (9/49). Most patients mostly responded to immunotherapy and had a good long-term prognosis. However, the overall recurrence rate of MNOS was higher than that of mono antibody-positive diseases. The existence of concurrent NMDAR antibodies should be suspected in patients with MOG antibody-associated disease having psychiatric symptoms, seizures, movement disorders, or autonomic dysfunction. Similarly, serum MOG antibody testing should be performed when patients with anti-NMDAR encephalitis present with atypical clinical manifestations, such as visual impairment and limb weakness, and neuroradiological findings, such as optic nerve, spinal cord, or infratentorial involvement or meningeal enhancement. Early detection of the syndrome and prompt treatment can be beneficial for these patients, and maintenance immunosuppressive therapy is recommended due to the high overall recurrence rate of the syndrome.

Paraneoplastic Neurologic Syndromes

OBJECTIVE

Progress is ongoing in understanding paraneoplastic neurologic disorders, with new syndromes and antibodies being described and more detailed evidence available to guide workup for diagnosis and treatment to improve outcomes. Many excellent reviews have summarized the molecular features of different antibodies, but this article emphasizes the clinical features of each syndrome that may help guide initial diagnosis and treatment, which often should occur before an antibody or cancer is found to confirm the diagnosis.

LATEST DEVELOPMENTS

Recent findings include updated diagnostic criteria with validated sensitivity and specificity, discovery of novel antibodies, and clinical findings that increase the likelihood of an underlying paraneoplastic disorder. Suggestive syndromes that have been recently identified include faciobrachial dystonic seizures and pilomotor auras in anti-leucine-rich glioma inactivated protein 1 encephalitis, extreme delta brush on EEG in N-methyl-d-aspartate (NMDA)-receptor encephalitis, déjà vu aura in anti-glutamic acid decarboxylase 65 (GAD65) encephalitis, and sleep disturbances in several disorders. In addition, there is confirmed utility of brain positron emission tomography (PET) and CSF markers, including carcinoembryonic antigen and oligoclonal bands, as well as improved tests for the presence of leptomeningeal cancer cells in CSF. Associations of cancer immunotherapies with paraneoplastic syndromes and herpes simplex virus encephalitis (and COVID-19) with NMDA-receptor encephalitis have been described.

ESSENTIAL POINTS

All neurologists should be aware of advances regarding paraneoplastic neurologic syndromes, as patients can present with a wide variety of neurologic symptoms and earlier diagnosis and treatment can improve outcomes.

Epidemiology of myelin oligodendrocyte glycoprotein antibody-associated disease: a review of prevalence and incidence worldwide

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is an inflammatory demyelinating disease of the central nervous system (CNS) with the presence of conformation-sensitive antibodies against MOG. The spectrum of MOGAD includes monophasic/relapsing optic neuritis, myelitis, neuromyelitis optica spectrum disorder (NMOSD) phenotype without aquaporin 4 (AQP4) antibodies, acute/multiphasic demyelinating encephalomyelitis (ADEM/MDEM)-like presentation, and brainstem and cerebral cortical encephalitis. There is no apparent female preponderance in MOGAD, and MOGAD can onset in all age groups (age at onset is approximately 30 years on average, and approximately 30% of cases are in the pediatric age group). While prevalence and incidence data have been available for AQP4+ NMOSD globally, such data are only beginning to accumulate for MOGAD. We reviewed the currently available data from population-based MOGAD studies conducted around the world: three studies in Europe, three in Asia, and one joint study in the Americas. The prevalence of MOGAD is approximately 1.3-2.5/100,000, and the annual incidence is approximately 3.4-4.8 per million. Among White people, the prevalence of MOGAD appears to be slightly higher than that of AQP4+ NMOSD. No obvious latitude gradient was observed in the Japanese nationwide survey. The data available so far showed no obvious racial preponderance or strong HLA associations in MOGAD. However, precedent infection was reported in approximately 20-40% of MOGAD cases, and this is worthy of further investigation. Co-existing autoimmune disorders are less common in MOGAD than in AQP4+ NMOSD, but NMDAR antibodies may occasionally be positive in patients with MOGAD. More population-based studies in different populations and regions are useful to further inform the epidemiology of this disease.

Investigating the association between neoplasms and MOG antibody-associated disease

Introduction

The association of myelin oligodendrocyte glycoprotein (MOG) antibody associated disease (MOGAD) and tumors has seldom been reported. We aim to investigate the occurrence of tumors in a cohort of patients with MOGAD and to describe their clinical features, in addition to previously reported cases.

Methods

We retrospectively identified patients with MOGAD (i.e., compatible clinical phenotype and positive MOG antibodies analysed with a live cell-based assay) from 1/1/2015 to 1/1/2023 who had a neoplasm diagnosed within 2  years from MOGAD onset. Furthermore, we performed systematic review of literature to identify previously reported cases. Clinical, paraclinical and oncological findings were collected and reported as median (range) or number (percentage).

Results

Two of 150 MOGAD patients (1%) had a concomitant neoplasm in our cohort. Fifteen additional cases were retrieved from literature. Median age was 39 (16-73) years-old, 12 patients were female. ADEM (n = 4;23.5%), encephalomyelitis (n = 3;17.6%), and monolateral optic neuritis (n = 2;11.8%) were the most frequent phenotypes. Median number of treatments was 1 (range 1-4), improvement was reported in 14/17 cases (82.4%). Oncological accompaniments were teratoma (n = 4), CNS (n = 3), melanoma (n = 2), lung (n = 2), hematological (n = 2), ovary (n = 1), breast (n = 1), gastrointestinal (n = 1), and thymic (n = 1) neoplasms. Median time from tumor diagnosis to MOGAD onset was 0 (range - 60 to 20) months. MOG expression in neoplastic tissue was reported in 2/4 patients. Median PNS-CARE score was 3 (range 0-7): 11 patients were classified as "non-PNS," 5 as "possible PNS," and 1 as "probable PNS."

Discussion

Our study confirms that MOG is a low-risk antibody for paraneoplastic neurological syndromes and that the clinical presentation and oncological accompaniments are extremely variable. Most of these patients were classified as non-PNS, whereas only a minority was diagnosed with possible/probable PNS, frequently in association with ovarian teratoma. These findings support the notion that MOGAD is not a paraneoplastic disease.

Myelin Oligodendrocyte Glycoprotein Antibody-associated Disease and an Incidental Thyroid Nodule

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a rare, immune-mediated demyelinating disease of the central nervous system (CNS) that has a predilection for children. Its association with malignancy or other autoimmune diseases is unclear. We present a case of MOGAD in a teenager with a coincidental thyroid malignancy and elevated intracranial pressure.