Treatment of MOG-IgG associated disease in paediatric patients: A systematic review

Myelin Oligodendrocyte Glycoprotein-Antibody Associated Disease: An Updated Review of the Clinical Spectrum, Pathogenetic Mechanisms and Therapeutic Management

Clinical syndromes associated with antibodies against myelin oligodendrocyte glycoprotein (MOG) are now recognized as a distinct neurological disease entity, and are gaining increasing attention. The pathogenic mechanisms underlying MOG-antibody disease (MOGAD) remain incompletely understood. Case series, facilitated by registries, and observational studies over the past few years have shed increasing light on the clinical aspects and therapeutic approaches of MOGAD. MOGAD may manifest with a variety of clinical syndromes, including acute disseminated encephalomyelitis (ADEM), autoimmune encephalitis, optic neuritis (ON) and transverse myelitis (TM). MOGAD can be either monophasic or relapsing. This review aims to provide a comprehensive updated description of the clinical spectrum, paraclinical features, and prognosis of MOG-antibody disease, as well as summarize its therapeutic considerations. Randomized clinical trials, standardized diagnostic criteria and treatment guidelines are the steps forward.

Oral corticosteroid dosage and taper duration at onset in myelin oligodendrocyte glycoprotein antibody-associated disease influences time to first relapse

BACKGROUND

We sought to identify an optimal oral corticosteroid regimen at the onset of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), which would delay time to first relapse while minimising cumulative corticosteroid exposure.

METHODS

In a retrospective multicentre cohort study, Cox proportional hazards models examined the relationship between corticosteroid course as a time-varying covariate and time to first relapse. Simon-Makuch and Kaplan-Meier plots identified an optimal dosing strategy.

RESULTS

We evaluated 109 patients (62 female, 57%; 41 paediatric, 38%; median age at onset 26 years, (IQR 8-38); median follow-up 6.2 years (IQR 2.6-9.6)). 76/109 (70%) experienced a relapse (median time to first relapse 13.7 months; 95% CI 8.2 to 37.9). In a multivariable model, higher doses of oral prednisone delayed time to first relapse with an effect estimate of 3.7% (95% CI 0.8% to 6.6%; p=0.014) reduced hazard of relapse for every 1 mg/day dose increment. There was evidence of reduced hazard of relapse for patients dosed ≥12.5 mg/day (HR 0.21, 95% CI 0.07 to 0.6; p=0.0036), corresponding to a 79% reduction in relapse risk. There was evidence of reduced hazard of relapse for those dosed ≥12.5 mg/day for at least 3 months (HR 0.12, 95% CI 0.03 to 0.44; p=0.0012), corresponding to an 88% reduction in relapse risk compared with those never treated in this range. No patient with this recommended dosing at onset experienced a Common Terminology Criteria for Adverse Events grade >3 adverse effect.

CONCLUSIONS

The optimal dose of 12.5 mg of prednisone daily in adults (0.16 mg/kg/day for children) for a minimum of 3 months at the onset of MOGAD delays time to first relapse.

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.

Pediatric acute bilateral optic neuritis: A case report

With the improvement of diagnostic technology, the diagnosis of optic neuritis (ON) has become increasingly accurate. Due to the special characteristics of the pediatric population, there is currently a lack of large-scale studies and related guidelines on pediatric ON. This case report describes the complete diagnosis and treatment process of a 7-year-old male patient with bilateral acute ON, from onset to symptom relief. During the outpatient stage, the patient was suspected of having different types of ON by different departments, but the diagnosis was confirmed through antibody testing after hospitalization. The treatment plan for this case was based on the current plan for adults and the prognosis was better than that of adults with similar characteristics. This suggests that pediatric ON has its own features and requires more case reports and clinical research for further exploration and summary.

Anti-Inflammatory and Immunomodulatory Effect of High-Dose Immunoglobulins in Children: From Approved Indications to Off-Label Use

BACKGROUND

The large-scale utilization of immunoglobulins in patients with inborn errors of immunity (IEIs) since 1952 prompted the discovery of their key role at high doses as immunomodulatory and anti-inflammatory therapy, in the treatment of IEI-related immune dysregulation disorders, according to labelled and off-label indications. Recent years have been dominated by a progressive imbalance between the gradual but constant increase in the use of immunoglobulins and their availability, exacerbated by the SARS-CoV-2 pandemic.

OBJECTIVES

To provide pragmatic indications for a need-based application of high-dose immunoglobulins in the pediatric context.

SOURCES

A literature search was performed using PubMed, from inception until 1st August 2023, including the following keywords: anti-inflammatory; children; high dose gammaglobulin; high dose immunoglobulin; immune dysregulation; immunomodulation; immunomodulatory; inflammation; intravenous gammaglobulin; intravenous immunoglobulin; off-label; pediatric; subcutaneous gammaglobulin; subcutaneous immunoglobulin. All article types were considered.

IMPLICATIONS

In the light of the current imbalance between gammaglobulins' demand and availability, this review advocates the urgency of a more conscious utilization of this medical product, giving indications about benefits, risks, cost-effectiveness, and administration routes of high-dose immunoglobulins in children with hematologic, neurologic, and inflammatory immune dysregulation disorders, prompting further research towards a responsible employment of gammaglobulins and improving the therapeutical decisional process.

Myelin oligodendrocyte glycoprotein antibody-associated disease as a novel presentation of central nervous system autoimmunity in a pediatric patient with Wiskott-Aldrich syndrome

BACKGROUND

Wiskott-Aldrich syndrome (WAS) is an X-linked primary immunodeficiency caused by mutations in the WAS gene that leads to increased susceptibility to infections, thrombocytopenia, eczema, malignancies, and autoimmunity. Central nervous system (CNS) autoimmune manifestations are uncommon.

CASE PRESENTATION

We describe the case of a five-year-old boy with refractory thrombocytopenia and iron deficiency anemia who developed relapsing bilateral optic neuritis. Myelin oligodendrocyte glycoprotein antibody (MOG-IgG) via serum fluorescence-activated cell sorting assay was positive (titer 1:100), confirming a diagnosis of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). At age six, molecular panel testing for genes associated with primary immunodeficiency identified a missense WAS gene variant. He was subsequently found to have decreased WAS protein expression, consistent with a diagnosis of WAS.

CONCLUSIONS

This case expands the reported spectrum of CNS autoimmunity associated with WAS and may help to inform long-term therapeutic options.

Attack phenotypes and disease course in pediatric MOGAD

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an autoimmune demyelinating condition that affects children differently than adults. We performed a literature review to assess the presentation and clinical course of pediatric MOGAD. The most common initial phenotype is acute disseminated encephalomyelitis, especially among children younger than five years, followed by optic neuritis (ON) and/or transverse myelitis. Approximately one-quarter of children with MOGAD have at least one relapse that typically occurs within three years of disease onset and often includes ON, even if ON was not present at onset. Clinical risk factors for a relapsing course have not been elucidated.

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.

Childhood Small-Vessel Primary Angiitis of the Central Nervous System: Overlap With MOG-Associated Disease

BACKGROUND

Childhood (c) primary angiitis of the central nervous system (PACNS) is a rare condition that most often affects small vessels (SV), is nearly exclusively lymphocytic, and devoid of vessel necrosis. Diagnosis of cSV-PACNS is challenging. We noted possible histological overlap of cSV-PACNS with myelin oligodendrocyte glycoprotein disease (MOGAD) on biopsy, prompting a 10-year retrospective review of our experience.

MATERIALS AND METHODS

Database-search for brain biopsy cases, age <18 years, performed for an acquired neurological deficit with suspicion of vasculitis, with histological evidence of lymphocytic small-vessel inflammation.

RESULTS

We identified 7 patients; 2/7 were serum-positive for anti-MOG antibodies and 1/7 for anti-NMDA antibodies. The remaining 4/7 proved to be idiopathic lymphocytic vasculitis/cSV-PACNS. All 7 showed overlapping features of lymphocytes permeating parenchymal SV walls, vessel wall distortion without fibrinoid necrosis, and absence of microglial clusters or intravascular thrombi. Tissue infarction was confined to a single case of idiopathic lymphocytic vasculitis. Although demyelination was diligently sought, only subtle demyelination was identified in the 2 MOGAD cases and absent in the remainder.

CONCLUSION

There is considerable histological overlap between cSV-PACNS and at least some cases of MOGAD or anti-NMDA-encephalitis; at diagnosis, the differential should include cSV-PACNS but correct classification requires post-biopsy serological testing.

[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.

Pediatric acute disseminated encephalomyelitis associated with myelin oligodendrocyte glycoprotein antibodies

Introduction. Myelin oligodendrocyte glycoprotein antibody associated disorders (MOGAD) are immune-mediated inflammatory conditions of the central nervous system (CNS) with a wide clinical phenotypic variability. In order to further understand the possible phenotype of MOGAD here we report a pediatric case of acute disseminated encephalomyelitis (ADEM) associated with MOG antibodies. Case outline. A previously healthy four-month-old infant presented due to a 1-day history of fever up to 39?C and vomiting. On admission, she was encephalopathic. Repetitive and frequent stereotyped dystonic movements were observed. Cerebrospinal fluid (CSF) examination showed pleocytosis (lymphocytes were predominant) and proteinorachy. CSF culture and virology results were negative. Serum MOG antibodies were positive. A prolonged electroencephalography (EEG) showed continuous high-amplitude slow rhythmic activity with captured stereotyped movement. Epileptic discharges were not seen. Although magnetic resonance imaging showed signs of acute demyelinating encephalomyelitis, our patient did not have seizures, despite neuroimaging findings of cortical lesions. Acute treatment with the corticosteroids led to excellent response with full recovery. Conclusion. This case emphasizes the inclusion of the MOG antibodies testing in the initial work-up in children presenting with acute encephalopathy associated with demyelinating or encephalitic abnormalities on brain and/or spinal magnetic resonance imaging even when the clinical phenotype is unusual. The prompt diagnosis of MOGAD is relevant for accurate disease monitoring and treatment strategies.