E.U. paediatric MOG consortium consensus: Part 4 - Outcome of paediatric myelin oligodendrocyte glycoprotein antibody-associated disorders.

There is increasing knowledge on the role of antibodies against myelin oligodendrocyte glycoprotein (MOG-abs) in acquired demyelinating syndromes and autoimmune encephalitis in children. Better understanding and prediction of outcome is essential to guide treatment protocol decisions. Therefore, this part of the Paediatric European Collaborative Consensus provides an oversight of existing knowledge of clinical outcome assessment in paediatric MOG-ab-associated disorders (MOGAD). The large heterogeneity in disease phenotype, disease course, treatment and follow-up protocols is a major obstacle for reliable prediction of outcome. However, the clinical phenotype of MOGAD appears to be the main determinant of outcome. Patients with a transverse myelitis phenotype in particular are at high risk of accruing neurological disability (motor and autonomic), which is frequently severe. In contrast, having a single episode of optic neuritis any time during disease course is broadly associated with a lower risk of persistent disability. Furthermore, MOG-ab-associated optic neuritis often results in good functional visual recovery, although retinal axonal loss may be severe. The field of cognitive and behavioural outcome and epilepsy following demyelinating episodes has not been extensively explored, but in recent studies acute disseminated encephalomyelitis (-like) phenotype in the young children was associated with cognitive problems and epilepsy in long-term follow-up. In conclusion, main domains of importance in determining clinical outcome in paediatric MOGAD are visual, motor, autonomic and cognitive function. A standardised evaluation of these outcome domains in all children is of importance to allow adequate rehabilitation and follow-up.

E.U. paediatric MOG consortium consensus: Part 1 - Classification of clinical phenotypes of paediatric myelin oligodendrocyte glycoprotein antibody-associated disorders.

Over the past few years, increasing interest in the role of autoantibodies against myelin oligodendrocyte glycoprotein (MOG-abs) as a new candidate biomarker in demyelinating central nervous system diseases has arisen. MOG-abs have now consistently been identified in a variety of demyelinating syndromes, with a predominance in paediatric patients. The clinical spectrum of these MOG-ab-associated disorders (MOGAD) is still expanding and differs between paediatric and adult patients. This first part of the Paediatric European Collaborative Consensus emphasises the diversity in clinical phenotypes associated with MOG-abs in paediatric patients and discusses these associated clinical phenotypes in detail. Typical MOGAD presentations consist of demyelinating syndromes, including acute disseminated encephalomyelitis (ADEM) in younger, and optic neuritis (ON) and/or transverse myelitis (TM) in older children. A proportion of patients experience a relapsing disease course, presenting as ADEM followed by one or multiple episode(s) of ON (ADEM-ON), multiphasic disseminated encephalomyelitis (MDEM), relapsing ON (RON) or relapsing neuromyelitis optica spectrum disorders (NMOSD)-like syndromes. More recently, the disease spectrum has been expanded with clinical and radiological phenotypes including encephalitis-like, leukodystrophy-like, and other non-classifiable presentations. This review concludes with recommendations following expert consensus on serologic testing for MOG-abs in paediatric patients, the presence of which has consequences for long-term monitoring, relapse risk, treatments, and for counselling of patient and families. Furthermore, we propose a clinical classification of paediatric MOGAD with clinical definitions and key features. These are operational and need to be tested, however essential for future paediatric MOGAD studies.

Treatment of MOG antibody associated disorders: results of an international survey.

INTRODUCTION: While monophasic and relapsing forms of myelin oligodendrocyte glycoprotein antibody associated disorders (MOGAD) are increasingly diagnosed world-wide, consensus on management is yet to be developed. OBJECTIVE: To survey the current global clinical practice of clinicians treating MOGAD. METHOD: Neurologists worldwide with expertise in treating MOGAD participated in an online survey (February-April 2019). RESULTS: Fifty-two responses were received (response rate 60.5%) from 86 invited experts, comprising adult (78.8%, 41/52) and paediatric (21.2%, 11/52) neurologists in 22 countries. All treat acute attacks with high dose corticosteroids. If recovery is incomplete, 71.2% (37/52) proceed next to plasma exchange (PE). 45.5% (5/11) of paediatric neurologists use IV immunoglobulin (IVIg) in preference to PE. Following an acute attack, 55.8% (29/52) of respondents typically continue corticosteroids for ≥ 3 months; though less commonly when treating children. After an index event, 60% (31/51) usually start steroid-sparing maintenance therapy (MT); after ≥ 2 attacks 92.3% (48/52) would start MT. Repeat MOG antibody status is used by 52.9% (27/51) to help decide on MT initiation. Commonly used first line MTs in adults are azathioprine (30.8%, 16/52), mycophenolate mofetil (25.0%, 13/52) and rituximab (17.3%, 9/52). In children, IVIg is the preferred first line MT (54.5%; 6/11). Treatment response is monitored by MRI (53.8%; 28/52), optical coherence tomography (23.1%; 12/52) and MOG antibody titres (36.5%; 19/52). Regardless of monitoring results, 25.0% (13/52) would not stop MT. CONCLUSION: Current treatment of MOGAD is highly variable, indicating a need for consensus-based treatment guidelines, while awaiting definitive clinical trials.

Aquaporin-4 IgG antibody-related disorders in patients with juvenile systemic lupus erythematosus.

OBJECTIVE: The aim of this study was to: (a) screen a large group of unselected patients with juvenile systemic lupus erythematosus for anti-aquaporin 4 antibodies (AQP4-Ab); (b) identify clinical and laboratory predictors of the presence of AQP4-Ab positivity in juvenile systemic lupus erythematosus. METHODS: Sera from 90 patients with juvenile systemic lupus erythematosus were tested for the presence of AQP4-Ab using a cell-based assay. Demographics, clinical and immunological features, treatment received were summarized. Fisher's exact test was used to identify clinical predictors of positivity for AQP4-Ab. RESULTS: Five of 90 (5.5%) patients tested positive for AQP4-Ab, all of which had neurological involvement, mainly transverse myelitis and optic neuritis. AQP4-Ab-positive patients were more likely to have neurological symptoms (P = 0.002), less likely to experience dermatological manifestations (P = 0.045), and less likely to have detectable anti-dsDNA antibodies (P = 0.022). These patients were also more likely to have received anti-epileptic (P = 0.023) and anti-coagulant (P = 0.007) drugs. CONCLUSIONS: The findings of this study indicate that some patients with juvenile systemic lupus erythematosus develop antibodies against aquaporin-4 and may be at risk of developing a neurological clinical phenotype. We suggest that all juvenile systemic lupus erythematosus patients should be systematically screened for the presence of AQP4-Ab and this may help identify a high risk for neurological involvement in juvenile systemic lupus erythematosus.

Paediatric acute disseminated encephalomyelitis followed by optic neuritis: disease course, treatment response and outcome.

BACKGROUND AND PURPOSE: Acute disseminated encephalomyelitis followed by optic neuritis (ADEM-ON) is a rare demyelinating syndrome that is different from multiple sclerosis and neuromyelitis optica spectrum disorder. The aim of this study was to describe the disease course, treatment response and outcome of children with ADEM-ON. METHODS: Children of <18 years of age were identified from six countries of the EU Paediatric Demyelinating Disease Consortium. Patients fulfilled the diagnostic criteria for ADEM followed by at least one ON. Anti-myelin oligodendrocyte glycoprotein (MOG) antibodies were tested in all patients. RESULTS: In this study of 17 patients (nine boys) with ADEM-ON, anti-myelin oligodendrocyte glycoprotein (MOG) antibodies were identified in 16 patients. Age at onset was 6.1 years (interquartile range, 5.1-9.2 years). Twelve patients received oral prednisolone and 10 received maintenance immunosuppression (e.g. azathioprine, intravenous immunoglobulins, Rituximab). During a follow-up of 5.3 years (interquartile range, 1.8-10.2 years), 54 relapses occurred with a median of 3 relapses per patient (range, 1-9 per patient). Patients relapsed on all treatments but no relapses occurred on a prednisolone dose >10 mg/day. Visual and cognitive residual deficits were common in this group. CONCLUSIONS: Acute disseminated encephalomyelitis followed by optic neuritis is an anti-MOG antibody-associated relapsing disorder that can have a heterogeneous disease course. Patients were refractory for maintenance immunosuppression and appeared to be corticosteroid-dependent. Further international collaborations are now required to unify guidelines in this difficult-to-manage group of patients.