Neuromyelitis optica in childhood: case report with sequential MRI findings

Pediatric Neuromyelitis Optica Spectrum Disorder: Case Series and Literature Review

Neuromyelitis Optica Spectrum Disorder (NMOSD) is a central nervous system (CNS) inflammatory demyelinating disease characterized by recurrent inflammatory events that primarily involve optic nerves and the spinal cord, but also affect other regions of the CNS, including hypothalamus, area postrema and periaqueductal gray matter. The aquaporin-4 antibody (AQP4-IgG) is specific for NMOSD. Recently, myelin oligodendrocyte glycoprotein antibodies (MOG-IgG) have been found in a group of AQP4-IgG negative patients. NMOSD is rare among children and adolescents, but early diagnosis is important to start adequate therapy. In this report, we present cases of seven pediatric patients with NMOSD and we review the clinical and neuroimaging characteristics, diagnosis, and treatment of NMOSD in children.

The Fc Receptor-Like 3 Polymorphisms (rs7528684, rs945635, rs3761959 and rs2282284) and The Risk of Neuromyelitis Optica in A Chinese Population

Neuromyelitis optica (NMO) appears to be a severe inflammatory demyelinating disease occurring in the central nervous system. Furthermore, the Fc receptor-like 3 (FCRL3) gene was previously found to be susceptible for a certain inflammatory demyelinating diseases (such as multiple sclerosis). The present study, therefore, was aimed to explore the possible association of FCRL3 gene polymorphisms with susceptibility to NMO in a Chinese Han population. Seven single nucleotide polymorphisms (SNPs) of FCRL3 were, respectively, genotyped in 132 NMO patients and 264 healthy controls via PCR assay. Moreover, the t-test and the chi-square test were used to estimate the association between genetic mutations of FCRL3 and the risk of NMO with Statistical Analysis System (SAS) software (Version 9.0). It was demonstrated that FCRL3_3, 5, 6 and 8, SNPs were remarkably associated with susceptibility to NMO in both allelic [OR = 1.50 (95% CI: 1.11-2.03, P = 0.008), OR = 1.44 (1.07-1.94, P = 0.015), OR = 1.45 (1.08-1.95, P = 0.014), and OR = 2.01 (1.13-3.60, P = 0.016)] and homozygous models [OR = 2.19 (95% CI: 1.19-3.99, P = 0.010), OR = 2.09 (1.15-3.80, P = 0.014), OR = 2.04 (1.13-3.67, P = 0.016), and OR = 5.33 (1.02-27.9, P = 0.027)]. However, the other 4 SNPs, FCRL3_4, FCRL3_7, FCRL3_9, did not show the significant associations with NMO. Conclusions in the present study could be drawn that 4 SNPs in FCRL3 (FCRL3_3*C, 5*C, 6*A, 8*G) might account for increased risk of NMO in a Chinese-Han population. Nevertheless, further cohort studies are in demand to validate the association in the future.

New insights into neuromyelitis optica

Neuromyelitis optica (NMO) is an idiopathic inflammatory disorder of the central nervous system (CNS) that preferentially affects the optic nerves and spinal cord. In Asia, NMO has long been considered a subtype of multiple sclerosis (MS). However, recent clinical, pathological, immunological, and imaging studies have suggested that NMO is distinct from MS. This reconsideration of NMO was initially prompted by the discovery of a specific antibody for NMO (NMO-IgG) in 2004. NMO-IgG is an autoantibody that targets aquaporin-4 (AQP4), the most abundant water channel in the CNS; hence, it was named anti-AQP4 antibody. Since it demonstrated reasonable sensitivity and high specificity, anti-AQP4 antibody was incorporated into new diagnostic criteria for NMO.The spectrum of NMO is now known to be wider than was previously recognized and includes a proportion of patients with recurrent, isolated, longitudinally extensive myelitis or optic neuritis, and longitudinally extensive myelitis or optic neuritis associated with systemic autoimmune disease or with brain lesions typical of NMO. In this context, a new concept of "NMO spectrum disorders" was recently introduced. Furthermore, seropositivity for NMO-IgG predicts future relapses and is recognized as a prognostic marker for NMO spectrum disorders. Humoral immune mechanisms, including the activation of B-cells and the complement pathway, are considered to play important roles in NMO pathogenesis. This notion is supported by recent studies showing the potential pathogenic role of NMO-IgG as an initiator of NMO lesions. However, a demonstration of the involvement of NMO-IgG by the development of active immunization and passive transfer in animal models is still needed. This review focuses on the new concepts of NMO based on its pathophysiology and clinical characteristics. Potential management strategies for NMO in light of its pathomechanism are also discussed.

Neuromyelitis optica: a distinct demyelinating disease of the central nervous system

OBJECTIVES

We review and discuss the pathogenesis, epidemiology, diagnosis as well as recent advances in the treatment of NMO. We also highlight areas of future research.

METHODS

A review was carried out on reports drawn from MEDLINE until 2007.

RESULTS

Neuromyelitis optica (NMO) is a relative uncommon demyelinating disease of the central nervous system (CNS) that preferentially affects the optic nerves and spinal cord. NMO follows an unpredictable course, being either monophasic or relapsing. The relapsing form of NMO primarily affects women with onset varying from childhood to adults in their 40s or elderly. Until recently, NMO was considered to be a variant of multiple sclerosis. However, in contrast to multiple sclerosis, NMO attacks are not mediated by T cells but rather by B cells and NMO-immunoglobulin G antibodies that target aquaporin-4. Humoral immune mechanisms, including complement activation plays an important role in the pathogenesis of NMO. At present, parenteral corticosteroids are widely employed as first-line treatment of optic neuritis and myelitis attacks, whereas therapeutic plasmapheresis is applied in the case of corticosteroids failure. Various strategies for the prevention of NMO relapses have been employed in small case series with modest activity.

CONCLUSION

Recent advances in the clinical, neuroimaging, laboratory and pathological hallmarks have established that NMO is a distinct demyelinating disease of the CNS.

The spectrum of neuromyelitis optica

Neuromyelitis optica (also known as Devic's disease) is an idiopathic, severe, demyelinating disease of the central nervous system that preferentially affects the optic nerve and spinal cord. Neuromyelitis optica has a worldwide distribution, poor prognosis, and has long been thought of as a variant of multiple sclerosis; however, clinical, laboratory, immunological, and pathological characteristics that distinguish it from multiple sclerosis are now recognised. The presence of a highly specific serum autoantibody marker (NMO-IgG) further differentiates neuromyelitis optica from multiple sclerosis and has helped to define a neuromyelitis optica spectrum of disorders. NMO-IgG reacts with the water channel aquaporin 4. Data suggest that autoantibodies to aquaporin 4 derived from peripheral B cells cause the activation of complement, inflammatory demyelination, and necrosis that is seen in neuromyelitis optica. The knowledge gained from further assessment of the exact role of NMO-IgG in the pathogenesis of neuromyelitis optica will provide a foundation for rational therapeutic trials for this rapidly disabling disease.

Multiple sclerosis in children: clinical diagnosis, therapeutic strategies, and future directions

The onset of multiple sclerosis (MS) in childhood poses diagnostic and therapeutic challenges, particularly if the symptoms of the first demyelinating event resemble acute disseminated encephalomyelitis (ADEM). MRI is an invaluable diagnostic tool but it lacks the specificity to distinguish ADEM from the first attack of MS. Advanced MRI techniques might have the required specificity to reveal whether the loss of integrity in non-lesional tissue occurs as a fundamental feature of MS. Although the onset of MS in childhood typically predicts a favourable short-term prognosis, some children are severely disabled, either physically or cognitively, and more than 50% are predicted to enter the secondary-progressive phase of the disease by the age of 30 years. Immunomodulatory therapies for MS and their safe application in children can improve long-term prognosis. Genetic and environmental factors, such as viral infection, might be uniquely amenable to study in paediatric patients with MS. Understanding the immunological consequences of these putative exposures will shed light on the early pathological changes in MS.

MRI findings in acute idiopathic transverse myelopathy in children

OBJECTIVE

To describe the clinical and MRI findings in three children with acute idiopathic myelopathy (AIM).

MATERIALS AND METHODS

Retrospective review of the clinical presentation, MRI findings and outcome of three patients diagnosed with acute idiopathic transverse myelitis.

RESULTS

Of note was the swift onset of symptoms in all patients, without any preceding illness or history of vaccination in two of the patients, and the rapid resolution of symptoms on steroid therapy in all the patients. MRI showed T2-weighted hyperintensity and patchy enhancement with gadolinium, but the extensive cord involvement did not correlate with the severity of presentation or outcome.

CONCLUSIONS

Our findings do not support that MRI evidence alone of diffuse myelopathy is a predictor of poor outcome in childhood AIM.

Prospective study of multiple sclerosis with early onset

Fifty-four subjects (36 females and 18 males) affected by clinically definite multiple sclerosis (MS) and with onset of the disease at 15 years of age or before were prospectively studied in five Italian MS centres. Female/male ratio was 4.7 in subjects with age > or = 12 years, suggesting a role of hormonal changes in triggering MS onset The mean follow-up duration was 10.9+/-5.6 years. The functional systems more frequently involved at onset were the pyramidal and brainstem (both in 28% of cases). The onset was monosymptomatic in 31 subjects (57%). The course was relapsing-remitting in 39 subjects (72%) and relapsing-progressive in 15 (28%). Disability was assessed by the Expanded Disability Status Scale (EDSS): the mean score after 8 years of follow up was 3.5 (+/-2.5). The score was <4 in 68% of cases, between 4 and 6 in 8% of cases, >6 in 24% of cases. Disability after 8 years was highly predicted by disability in the first year (p=0.008). There was a tendency to a worse prognosis in relation to the number of relapses in the first 2 years (p=0.08). The outcome was not influenced by the characteristics of symptoms at onset age and gender.