Clinical, CSF, and MRI findings in Devic's neuromyelitis optica

Acute inflammatory demyelinating optic neuritis: evidence-based visual and neurological considerations

BACKGROUND

Optic neuritis (ON) is an acute inflammatory demyelinating disorder of the optic nerve that occurs most often in young adults. It can be a monophasic or polyphasic disease isolated to the optic nerve(s) or can be associated with a more widespread demyelinating disorder of the central nervous system such as multiple sclerosis (MS) or neuromyelitis optica. Advances in therapeutics that modify the risk of progression to MS have emphasized accurate diagnosis and risk assessment of patients with ON.

REVIEW SUMMARY

ON usually presents with acute unilateral visual loss associated with ocular pain exacerbated by eye movements. Similar to results found in studies assessing corticosteroid used in MS relapses, intravenous methylprednisolone accelerates visual recovery from ON but has no impact on long-term visual outcome. A clinically isolated syndrome (CIS), such as ON, is a clinical demyelinating event that is often the initial attack of relapsing-remitting MS. Disease modifying drugs, in particular interferons-beta, have been shown to reduce the risk of MS conversion in high-risk patients presenting with a CIS. The exact timing and patient selection for the initiation of treatment remain controversial.

CONCLUSION

ON is the best studied CIS. The visual prognosis is excellent in most cases regardless of whether the patient is treated with corticosteroids or not. Three recently completed prospective, randomized, double-blinded, placebo-controlled studies have shown that starting a disease-modifying drug at the time of a CIS can reduce the rate of development of MS. However, better diagnostic tools are needed to precisely predict the conversion to MS and the factors influencing disease severity to determine the most appropriate therapeutic paradigm and avoid unnecessary treatment.

A prominent elevation of glial fibrillary acidic protein in the cerebrospinal fluid during relapse in neuromyelitis optica

Neuromyelitis optica (NMO) is a neurologic disease characterized by severe optic neuritis, longitudinally extended, transverse myelitis and serum aquaporin-4 (AQP4) antibody. Our recent neuropathological study revealed the extensive loss of AQP4 and glial fibrillary acidic protein (GFAP), an astrocyte-specific protein, in NMO lesions, but not in MS lesions, suggesting that severe astrocytic damage or dysfunction may be related to the pathogenesis of NMO. Here we report a patient of NMO, in which the cerebrospinal fluid (CSF) levels of GFAP were measured both during relapse of myelitis and after high-dose intravenous methylprednisolone (HIMP). The patient was a 34-year old woman with two previous episodes of optic neuritis. She developed myelitis longitudinally extending from C3 to T12 with contrast enhancement, and was AQP4 antibody-positive. In the acute phase, the GFAP level in the cerebrospinal fluid (CSF) was prominently elevated (18,966.7 ng/ml) as compared with controls (0.6 +/- 0.33 ng/ml). However, following HIMP, the clinical and MRI findings improved, and the CSF-GFAP level was near-normal (2.1 ng/ml). The CSF of myelin basic protein was also elevated in relapse (1,016.0 pg/ml), and became lower but still remained high (158.7 pg/ml) after HIMP compared with controls (3.36 +/- 3.83 pg/ml). The prominent elevation of the CSF-GFAP level in relapse of NMO, followed by its sharp decline after therapy, suggests severe astrocytic damage with a temporal profile distinct from that of the demyelinating process in NMO. CSF-GFAP may be useful as a biomarker of NMO.

Minor salivary gland inflammation in Devic’s disease and longitudinally extensive myelitis

Devic’s disease is often considered as a variant of multiple sclerosis (MS). However, evidence suggests that Devic’s disease may be distinct from MS. Devic’s disease can coexist with connective tissue diseases, particularly Sjögren’s disease, but this association is rare with MS. Diagnosis of Sjögren’s disease in patients with neurological symptoms is often difficult. During early stages of Sjögren’s disease, patients may not fulfill all criteria for Sjögren’s disease. A high percentage of patients with Sjögren’s disease have inflammatory infiltrates in minor salivary glands, and this may be a reliable indicator of early or subclinical disease. We show high prevalence (80%) of salivary gland inflammation in Devic’s disease and longitudinally extensive transverse myelitis (LETM). We diagnosed 16 patients with Devic’s disease, and 2 of these satisfied criteria for Sjögren’s disease as did 2 of 9 patients with LETM. Anti-SSA/B titers were infrequently elevated. Although most did not satisfy criteria for Sjögren’s disease. 9 of 12 Devic’s disease patients and 7 of 8 LETM patients had severe salivary gland inflammation. Thus: (1) patients with Devic’s disease or with LETM who have positive labial biopsies but do not satisfy criteria for Sjögren’s disease could have subclinical Sjögren’s diseases. Alternatively, (2) as patients with Devic’s disease have elevated titers of several autoantibodies, so there may exist a set of antibodies that react with antigens in minor salivary glands and cause inflammation. Minor salivary gland biopsy is more sensitive than anti-SSA/B serology in providing histological evidence for possible Sjögren’s disease with CNS lesions.

Rehabilitation of neuromyelitis optica (Devic syndrome): three case reports

We describe the inpatient clinical rehabilitation course of three patients with neuromyelitis optica (NMO; Devic syndrome). These patients had varying functional deficits. Each patient improved in several functional independence measures (FIM domains) but had minimal to no progress in other domains after acute rehabilitation stays between 1 and 1.5 mos. NMO is a severe central nervous system demyelinating syndrome distinct from MS, characterized by optic neuritis, myelitis, and at least two of three criteria: longitudinally extensive cord lesion, MRI nondiagnostic for multiple sclerosis, or NMO-IgG seropositivity. Persons with NMO may demonstrate improved function with rehabilitation efforts; though gains may be lost to relapse. Future immunomodulatory intervention may augment the benefits of rehabilitation.

Mechanisms of disease: aquaporin-4 antibodies in neuromyelitis optica

Neuromyelitis optica (NMO) is a rare CNS inflammatory disorder that predominantly affects the optic nerves and spinal cord. Recent serological findings strongly suggest that NMO is a distinct disease rather than a subtype of multiple sclerosis. In NMO, serum antibodies, collectively known as NMO-IgG, characteristically bind to cerebral microvessels, pia mater and Virchow-Robin spaces. The main target antigen for this immunoreactivity has been identified as aquaporin-4 (AQP4). The antibodies are highly specific for NMO, and they are also found in patients with longitudinally extensive transverse myelitis without optic neuritis, which is thought to be a precursor to NMO in some cases. An antibody-mediated pathogenesis for NMO is supported by several observations, including the characteristics of the AQP4 antibodies, the distinct NMO pathology--which includes IgG and complement deposition and loss of AQP4 from spinal cord lesions--and emerging evidence of the beneficial effects of B-cell depletion and plasma exchange. Many aspects of the pathogenesis, however, remain unclear.

Devic’s neuromyelitis optica: a critical review

Devic's neuromyelitis optica (NMO) is an idiopathic inflammatory demyelinating and necrotizing disease characterized by predominant involvement of the optic nerves and spinal cord. In Asian countries relapsing NMO has been known as opticospinal multiple sclerosis. It has long been debated if NMO is a variant of multiple sclerosis (MS) or a distinct disease. Recent studies have shown that NMO has more frequently a relapsing course, and results from attack to aquaporin-4 which is the dominant water channel in the central nervous system, located in foot processes of the astrocytes. Distinctive pathological features of NMO include perivascular deposition of IgG and complement in the perivascular space, granulocyte and eosinophil infiltrates and hyalinization of the vascular walls. These features distinguish NMO from other demyelinating diseases such as MS and acute demyelinating encephalomyelopathy. An IgG-antibody that binds to aquaporin-4, named NMO-IgG has high sensitivity and specificity. Magnetic resonance imaging (MRI) studies have revealed that more frequently there is a long spinal cord lesion that extends through three or more vertebral segments in length. Brain MRI lesions atypical for MS are found in the majority of cases. Treatment in the acute phase includes intravenous steroids and plasma exchange therapy. Immunosupressive agents are recommended for prophylaxis of relapses.

[Neuromyelitis optica]

Neuromyelitis optica (NMO, Devic syndrome) is a rare demyelinating disease of the central nervous system which mostly follows a relapsing course. Key features of this disorder include unilateral or bilateral optic neuritis and longitudinally extensive myelitis (> or = three segments). Brain lesions are rarely present at onset. They may however evolve during the course of disease but usually remain asymptomatic. The histopathology of NMO is suggestive of an underlying humoral autoimmune pathomechanism and indicates that NMO is a distinct entity rather than a variant of multiple sclerosis. The recent detection of NMO-specific serum autoantibodies against the water channel aquaporin-4 (Aqp4) is of significant diagnostic relevance and classifies NMO as the first inflammatory demyelinating disorder of the CNS with a defined autoantigen. More recent therapeutic strategies such as plasma exchange or pharmacological B-cell depletion are expected to improve long-term prognosis of NMO.

Neuromyelitis optica: clinical syndrome and the NMO-IgG autoantibody marker

Neuromyelitis optica (NMO) is a severe demyelinating disease of the CNS that preferentially affects the optic nerves and spinal cord, tends to relapse, and results in early permanent disability for most affected patients. A new autoantibody marker called neuromyelitis optica immunoglobulin G (NMO-IgG), which targets the water channel protein aquaporin-4, is highly specific for NMO. The marker has demonstrated that the NMO spectrum of disorders is wider than previously known and includes some patients with single-episode or recurrent longitudinally extensive myelitis, recurrent isolated optic neuritis, Asian optic-spinal multiple sclerosis, and patients with co-existing systemic autoimmune diseases such as lupus erythematosus or Sjögren's syndrome. We review the place of NMO within the nosology of CNS demyelinating diseases, the discovery of NMO-IgG and its impact on the definition of NMO and its spectrum, implications for understanding NMO pathogenesis, and informing treatment decisions.

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.

Devic's neuromyelitis optica in an infant case

Devic's neuromyelitis optica was orginally described as an acute severe monophasic syndrome characterised by myelitis and optic neuritis. The mean age at onset was reported to be around 40 years, with a wide range. However, Devic's neuromyelitis optica has also been seen in children. Prognosis of the syndrome was poor, and no satisfactory treatment was known. This article reports a 23-month-old boy with acute myelitis and optic neuritis who was diagnosed with Devic's neuromyelitis optica. The response of the patient to therapy was poor, and he developed severe sequelae.

Low-dose corticosteroids reduce relapses in neuromyelitis optica: a retrospective analysis

Neuromyelitis optica (NMO) is a relapsing neurologic disease characterized by severe optic neuritis and transverse myelitis. A disease-modifying therapy for NMO has not been established. We retrospectively analysed the effect of low-dose corticosteroid (CS) monotherapy on the annual relapse rate in nine patients with NMO. We divided the clinical course in each patient into two periods; the CS Period in which CS was administered, and the No CS Period in which CS was not administered. Periods related to other immunological therapies, such as high-dose methylprednisolone, immunosuppressants, interferon-beta, and plasma exchange, were excluded. As a result, the annual relapse rate during the CS Periods [median, 0.49 (range, 0—1.31)] was found to be significantly lower than that during the No CS Periods [1.48 (0.65—5.54)]. As for the dose of CS, relapses occurred significantly more frequently with `10 mg/day or less' than with `over 10 mg/day' (odds ratio: 8.75). The results of the present study suggest a beneficial effect of low-dose CS monotherapy in reducing relapses in NMO. Multiple Sclerosis 2007; 13: 968—974. http://msj.sagepub.com

Relapsing Neuromyelitis Optica and Relapsing-Remitting Multiple Sclerosis: Differentiation at Diffusion-Tensor MR Imaging of Corpus Callosum

PURPOSE

To prospectively assess sensitivity and specificity of diffusion indexes of the corpus callosum (CC) for differentiating relapsing neuromyelitis optica (RNMO) from relapsing-remitting multiple sclerosis (RRMS), by using final clinical diagnosis as the reference standard.

MATERIALS AND METHODS

Participants provided informed consent; the study was approved by the institutional review board. Forty-six consecutive patients with RRMS (18 men, 28 women; mean age, 37.7 years; range, 18-58 years) and 26 consecutive patients with RNMO (two men, 24 women; mean age, 38.6 years; range, 19-59 years) underwent diffusion-tensor magnetic resonance imaging. Mean diffusivity (MD) and fractional anisotropy (FA) of the region of interest (ROI) of the CC in the midsagittal plane were measured and used as discriminative indexes. Bayesian classification with leave-one-out cross-validation was used to determine diagnostic accuracy. Differences in diffusion indexes of ROIs among groups were evaluated by using the Kruskal-Wallis test, followed by the Mann-Whitney U test for multiple comparisons and Bonferroni correction.

RESULTS

Mean MD (8.48 x 10(-4) mm(2)/sec) and FA (0.729) of the ROI in patients with RNMO were significantly (P<.001) different from those (MD=10.64 x 10(-4) mm(2)/sec, FA=0.599) in patients with RRMS. Sensitivity and specificity for differentiation were 92.3% (24 of 26 patients with RNMO) and 93.5% (43 of 46 patients with RRMS) for FA and 88.5% (23 of 26 patients with RNMO) and 89.1% (41 of 46 patients with RRMS) for MD, respectively.

CONCLUSION

Measurement of diffusion indexes of the CC may be useful for distinguishing patients with RNMO from those with RRMS.

Sclérose en plaques : aspects cliniques, encéphalomyélites aiguës disséminées, neuromyélites optiques et variantes inflammatoires

Multiple sclerosis (MS) has been described for more than a century, but its cause remains unknown. Numerous reports were written concerning borderline forms of the disease. In the present review we present MS related disorders such as neuromyelitis optica and acute demyelinating encephalomyelitis.

Anti-aquaporin 4 antibody in selected Japanese multiple sclerosis patients with long spinal cord lesions

Multiple sclerosis (MS) in Asian populations is often characterized by the selective involvement of the optic nerve (ON) and spinal cord (SP) (OSMS) in contrast to classic MS (CMS), where frequent lesions are observed in the cerebrum, cerebellum or brainstem. In Western countries, inflammatory demyelinating disease preferentially involving the ON and SP is called neuromyelitis optica (NMO). Recently, Lennon et al. discovered that NMO-IgG, shown to bind to aquaporin 4 (AQP4), could be a specific marker of NMO and also of Japanese OSMS whose clinical features were identical to NMO having long spinal cord lesions extending over three vertebral segments (LCL). To examine this antibody in larger populations of Japanese OSMS patients in order to know its epidemiological and clinical spectra, we established an immunohistochemical detection system for the anti-AQP4 antibody (AQP4-Ab) using the AQP4-transfected human embryonic kidney cell line (HEK-293) and confirmed AQP4-Ab positivity together with the immunohistochemical staining pattern of NMO-IgG in approximately 60% of Japanese OSMS patients with LCL. Patients with OSMS without LCL and those with CMS were negative for this antibody. Our results accorded with those of Lennon et al. suggest that Japanese OSMS with LCL may have an underlying pathogenesis in common with NMO.

Revised diagnostic criteria for neuromyelitis optica (NMO)

We analyzed neuromyelitis optica (NMO) IgG in the serum or CSF samples from 46 patients with suspected NMO (28) and limited forms of NMO (18). One hundred and fifteen samples from multiple sclerosis (MS) patients were included as controls. The final clinical diagnosis after follow-up was 16 NMO, 12 MS, 11 transverse myelitis (TM) and seven recurrent optic neuritis (RON). NMO-IgG was detected in 62.5% of NMO, 50% of the recurrent longitudinally extensive TM, 14.3% of the RON but in none of the MS patients. The authors then compared the newly revised diagnostic criteria for NMO with the criteria published in 1999, in the 28 patients with suspected NMO. The revised criteria had higher specificity, and positive and negative predictive value (83.3% vs. 25%; 87.5% vs. 62.5; 83.3% vs. 75%), but slightly lower sensitivity (87.5% vs. 93.7%). Our study confirms NMO-IgG as a highly specific marker of NMO, and the usefulness of the revised diagnostic criteria in predicting a diagnosis of NMO.

Antibody to aquaporin 4 in the diagnosis of neuromyelitis optica

BACKGROUND

Neuromyelitis optica (NMO) is a demyelinating disease of the central nervous system (CNS) of putative autoimmune aetiology. Early discrimination between multiple sclerosis (MS) and NMO is important, as optimum treatment for both diseases may differ considerably. Recently, using indirect immunofluorescence analysis, a new serum autoantibody (NMO-IgG) has been detected in NMO patients. The binding sites of this autoantibody were reported to colocalize with aquaporin 4 (AQP4) water channels. Thus we hypothesized that AQP4 antibodies in fact characterize NMO patients.

METHODS AND FINDINGS

Based on these observations we cloned human water channel AQP4, expressed the protein in a eukaryotic transcription/translation system, and employed the recombinant AQP4 to establish a new radioimmunoprecipitation assay (RIPA). Indeed, application of this RIPA showed that antibodies against AQP4 exist in the majority of patients with NMO (n = 37; 21 positive) as well as in patients with isolated longitudinally extensive transverse myelitis (n = 6; six positive), corresponding to a sensitivity of 62.8% and a specificity of 98.3%. By contrast, AQP4 antibodies were virtually absent in 291 other participants, which included patients with MS (n = 144; four positive), patients with other inflammatory and noninflammatory neurological diseases (n = 73; one positive), patients with systemic autoimmune diseases (n = 45; 0 positive), and healthy participants (n = 29; 0 positive).

CONCLUSIONS

In the largest series reported so far to our knowledge, we quantified AQP4 antibodies in patients with NMO versus various other diseases, and showed that the aquaporin 4 water channel is a target antigen in a majority of patients with NMO. The newly developed assay represents a highly specific, observer-independent, and easily reproducible detection method facilitating clinically relevant discrimination between NMO, MS, and other inflammatory diseases.

Tuberculous encephalopathy: a reappraisal

Forty years ago Dastur and Udani described a form of diffuse cerebral damage in tuberculosis, which they called tuberculous encephalopathy. Their pathological and clinical observations led them to propose an immune pathogenesis. Although there have been no convincing independently reported series, the entity is now established in the tuberculosis literature. We review the literature on tuberculous encephalopathy, and suggest alternative aetiopathogenetic explanations for the appearances of the brain in these cases. We propose that tuberculosis is one of many infections which may be associated with a range of immune, drug-related, hypoxic-ischaemic and toxic diffuse brain pathologies.

Idiopathic inflammatory-demyelinating diseases of the central nervous system

Idiopathic inflammatory-demyelinating diseases (IIDDs) include a broad spectrum of central nervous system disorders that can usually be differentiated on the basis of clinical, imaging, laboratory and pathological findings. However, there can be a considerable overlap between at least some of these disorders, leading to misdiagnoses or diagnostic uncertainty. The relapsing-remitting and secondary progressive forms of multiple sclerosis (MS) are the most common IIDDs. Other MS phenotypes include those with a progressive course from onset (primary progressive and progressive relapsing) or with a benign course continuing for years after onset (benign MS). Uncommon forms of IIDDs can be classified clinically into: (1) fulminant or acute IIDDs, such as the Marburg variant of MS, Baló's concentric sclerosis, Schilder's disease, and acute disseminated encephalomyelitis; (2) monosymptomatic IIDDs, such as those involving the spinal cord (transverse myelitis), optic nerve (optic neuritis) or brainstem and cerebellum; and (3) IIDDs with a restricted topographical distribution, including Devic's neuromyelitis optica, recurrent optic neuritis and relapsing transverse myelitis. Other forms of IIDD, which are classified clinically and radiologically as pseudotumoral, can have different forms of presentation and clinical courses. Although some of these uncommon IIDDs are variants of MS, others probably correspond to different entities. MR imaging of the brain and spine is the imaging technique of choice for diagnosing these disorders, and together with the clinical and laboratory findings can accurately classify them. Precise classification of these disorders may have relevant prognostic and treatment implications, and might be helpful in distinguishing them from tumoral or infectious lesions, avoiding unnecessary aggressive diagnostic or therapeutic procedures.

Neuromyelitis optica with clinical and histopathological involvement of the brain

Diagnostic criteria for neuromyelitis optica (NMO) state that there should be no active disease outside the optic nerves and spinal cord. However, several cases have been described with symptomatic brain involvement. We describe an autopsy case of a patient with NMO and symptomatic involvement of the brain. The histopathology of the brain lesions is typical for NMO, with extensive macrophage infiltration, including perivascular accumulation of large numbers of eosinophils. This is the first case that clearly shows that in NMO, the histopathology of the brain lesions is identical to that of the lesions in the optic nerves and spinal cord.

A three-dimensional approach for understanding the spectrum of idiopathic inflammatory demyelinating disorders: importance of the 'attack-related severity' axis

Understanding the spectrum of idiopathic inflammatory demyelinating disorders (IIDD) of the central nervous system is an important issue for accurate diagnosis and advancing research on the pathogenesis as well as treatment strategies, but the nosology and the classification of the IIDD remains confusing. Until now, we have tried to apply each disorder within the spectrum to an adequate co-ordinate on a two-dimensional plane. One axis is clinical course and the other is lesion distribution. We reviewed some disorders of the IIDD spectrum, and our recent findings on the fulminant nature of each attack and the expansion of each lesion, which we called attack-related severity in Japanese multiple sclerosis (MS). From our findings and the literature, attack-related severity appears to be a third important factor, in addition to lesion distribution and clinical course. Introduction of the third axis produces a three-dimensional space for a better understanding of the heterogeneous characteristics of IIDD and 'MS' syndrome, and can advance treatment strategies for these disorders. As severe attacks seem to be relatively common in Asians but rare in the west, ethnic-related heterogeneity should be considered in understanding the spectrum of IIDD, and there is an urgent need to develop a common general concept of the spectrum, especially for MS.

Neuromyelitis Optica: New Findings on Pathogenesis

Neuromyelitis optica (NMO) is an idiopathic CNS demyelinating disorder that preferentially involves the optic nerve and spinal cord. Diverse sources of evidence support the hypothesis that NMO is distinct from classical multiple sclerosis (MS) and that the pathogenesis of NMO is dominated by humoral mechanisms. Such evidence includes clinical observations that systemic autoimmune diseases often coexist with NMO and that therapeutic plasmapheresis may provide meaningful rescue therapy for severe clinical attacks, immunopathologic studies that demonstrate prominent complement activation and immunoglobulin deposition, and the discovery of the serum autoantibody NMO-IgG, a potential NMO biomarker that targets aquaporin-4 (AQP4). The NMO-IgG marker is present in a majority of patients with "NMO-spectrum disorders," including isolated or recurrent longitudinally extensive transverse myelitis, recurrent optic neuritis with negative brain imaging, and the Asian optic-spinal form of MS. Preliminary experiments demonstrate that NMO-IgG can modulate AQP4 function and fix complement, characteristics that suggest it has the potential to be pathogenic in NMO. Other immunologic differences among NMO, NMO-spectrum disorders, and classical MS are reviewed.

Diagnosis and Treatment of Neuromyelitis Optica

BACKGROUND

Neuromyelitis optica (NMO) is an uncommon CNS demyelinating syndrome often mistaken for severe multiple sclerosis (MS). Several clinical, laboratory, and neuroimaging characteristics may accurately distinguish NMO from MS early in the disease course.

REVIEW SUMMARY

NMO is usually a relapsing disorder associated with early, severe, attack-related residual disability. It is associated with a highly specific antibody marker, NMO-IgG, which targets the water channel aquaporin-4. Revised NMO diagnostic criteria require optic neuritis, acute myelitis, and 2 of the following 3 characteristics: disease-onset brain magnetic resonance imaging (MRI) that is nondiagnostic for MS, contiguous spinal cord MRI lesion extending over 3 or more vertebral segments, and NMO-IgG seropositive status. Symptoms referable to central nervous system regions other than the optic nerve and spinal cord do not necessarily exclude the diagnosis of NMO, nor does the presence of brain MRI lesions. NMO-IgG has facilitated an appreciation that the spectrum of NMO is wider than previously recognized, and includes a proportion of patients with each of recurrent longitudinally extensive myelitis, recurrent isolated optic neuritis, and Japanese opticospinal MS. In contrast to typical MS, clinical experience and case series suggest that NMO requires long-term immunosuppressive therapy.

CONCLUSIONS

NMO can be reliably differentiated from MS at an early stage using validated diagnostic criteria. The spectrum of NMO is wider than previously appreciated. Accurate, early diagnosis is critical to facilitate initiation of immunosuppressive therapy for attack prevention.

Natural history of the visual impairment of relapsing neuromyelitis optica

PURPOSE

To describe the clinical features and natural history of the visual impairment of relapsing neuromyelitis optica.

DESIGN

Prospective observational case series.

PARTICIPANTS

Thirty patients of Afro-Caribbean origin with neuromyelitis optica and 47 patients with multiple sclerosis.

METHODS

A complete ophthalmologic examination was performed with each ocular attack and during a remission period at least 6 months after the last attack.

MAIN OUTCOME MEASURES

Incidence of unilateral and bilateral optic neuritis and incidence of unilateral and bilateral severe visual loss, defined as visual acuity (VA) < or = 20/200.

RESULTS

Twenty-eight patients (93%) with neuromyelitis optica were female and 2 (7%) were male. The mean age of onset was 30+/-10.5 years. Mean disease duration was 9.5+/-5.4 years. Neuromyelitis optica first manifested by an episode of optic neuritis in 23 cases (76.6%), bilateral in 4. The average number of ocular attacks per patient was 2.7+/-1.6. Twenty-one patients (70%) showed impairment in both eyes. Median times from onset to unilateral optic neuritis, bilateral optic neuritis, mono-ocular severe visual loss, and binocular severe visual loss were 0+/-0.08, 1+/-1.6, 2+/-0.8, and 13+/-3 years, respectively. Fifteen patients (50%) experienced severe visual loss in both eyes and 6 (20%) in one eye. Severe visual loss occurred in as few as 2 attacks.

CONCLUSION

This study is the largest series of relapsing neuromyelitis optica in a population of African descent. Neuromyelitis optica's visual impairment is very severe; it contrasts drastically with that typically observed in multiple sclerosis. We confirmed that the prognosis for optic neuritis in patients with neuromyelitis optica is worse than the prognosis in patients with multiple sclerosis.

[Devic disease]

Devic disease, also known as neuromyelitis optica, is a severe rare condition characterized clinically by one or more episodes of optical neuritis and myelitis. Pathologically, it is characterized by extensive demyelination associated with axon loss and deposits of complement and immunoglobulins (IgM) within the lesions. Specific antibodies for this disease (IgG NMO) were recently identified. Immunosuppressive treatment is currently the best option for preventing relapse.

Spontaneous opticospinal encephalomyelitis in a double-transgenic mouse model of autoimmune T cell/B cell cooperation

We describe a double-transgenic mouse strain (opticospinal EAE [OSE] mouse) that spontaneously develops an EAE-like neurological syndrome closely resembling a human variant of multiple sclerosis, Devic disease (also called neuromyelitis optica). Like in Devic disease, the inflammatory, demyelinating lesions were located in the optic nerve and spinal cord, sparing brain and cerebellum, and the murine lesions showed histological similarity with their human correlates. OSE mice have recombination-competent immune cells expressing a TCR-alphabeta specific for myelin oligodendrocyte glycoprotein (MOG) aa 35-55 peptide in the context of I-Ab along with an Ig J region replaced by the recombined heavy chain of a monoclonal antibody binding to a conformational epitope on MOG. OSE mouse B cells bound even high dilutions of recombinant MOG, but not MOG peptide, and processed and presented it to autologous T cells. In addition, in OSE mice, but not in single-transgenic parental mice, anti-MOG antibodies were switched from IgM to IgG1.

Spontaneous opticospinal encephalomyelitis in a double-transgenic mouse model of autoimmune T cell/B cell cooperation

We describe a double-transgenic mouse strain (opticospinal EAE [OSE] mouse) that spontaneously develops an EAE-like neurological syndrome closely resembling a human variant of multiple sclerosis, Devic disease (also called neuromyelitis optica). Like in Devic disease, the inflammatory, demyelinating lesions were located in the optic nerve and spinal cord, sparing brain and cerebellum, and the murine lesions showed histological similarity with their human correlates. OSE mice have recombination-competent immune cells expressing a TCR-alphabeta specific for myelin oligodendrocyte glycoprotein (MOG) aa 35-55 peptide in the context of I-Ab along with an Ig J region replaced by the recombined heavy chain of a monoclonal antibody binding to a conformational epitope on MOG. OSE mouse B cells bound even high dilutions of recombinant MOG, but not MOG peptide, and processed and presented it to autologous T cells. In addition, in OSE mice, but not in single-transgenic parental mice, anti-MOG antibodies were switched from IgM to IgG1.

MRI and the diagnosis of multiple sclerosis: expanding the concept of "no better explanation"

Although the diagnosis of multiple sclerosis relies on the demonstration of disease dissemination in space and time, the exclusion of other neurological disorders is also essential. The limited specificity of abnormalities disclosed by MRI may increase the likelihood of diagnosis of multiple sclerosis in patients affected by other disorders. The available criteria for diagnosis of multiple sclerosis have not taken advantage of the potential of MRI to detect features "not suggestive" of multiple sclerosis. Recognition of such features in the work-up of patients suspected of having multiple sclerosis may reduce the likelihood of a false positive diagnosis of the disorder in some, while suggesting the correct alternative diagnosis in other patients. On the basis of this, a workshop of the European MAGNIMS (Magnetic Resonance Network in Multiple Sclerosis) was held to define a series of MRI red flags in the setting of clinically suspected multiple sclerosis that is derived from evidence-based findings and educated guesses. The presence of such red flags should alert clinicians to reconsider the differential diagnosis more extensively. In this review we will report on the conclusions of this international consensus, which should represent a first step beyond the concept of "no better explanation", and inform future diagnostic criteria for multiple sclerosis.

Myélite aiguë transverse idiopathique : application des nouveaux critères diagnostiques à une cohorte de 17 patients

INTRODUCTION

Idiopathic Acute Transverse Myelitis (ATM) is an inflammatory and immune-mediated disorder, distinct from infectious ATM, ATM of systemic lupus erythematosus or Sjögren's syndrome, and medullary manifestation of multiple sclerosis. Prognosis is not well-known.

OBJECTIVE

To evaluate clinical, paraclinical and pronognosis data in patients selected with new diagnosis criteria, classically described in idiopathic ATM.

METHODS

Seventeen patients with diagnosis criteria were retrospectively (1996-2005) studied. A telephone investigation was conducted in 2005 to obtained data on the clinical course.

RESULTS

Seven men and 10 women, ranging in age from 15 to 75 years (mean: 39.8 years) met these new criteria. Our study showed that epidemiological and clinical findings as well as laboratory results were in agreement with those presented in the literature. Conversely, prognosis was better since 76p.cent of the patients could walk without assistance. The clinical presentation of some of our patients and/or their progression towards other multifocal inflammatory disorders, suggests there might be links between ATM, neuromyelitis optica (NMO) and Acute Dissemined Encephalomyelitis (ADEM).

CONCLUSION

Patients with idiopathic ATM, selected with new criteria, have a rather good prognosis. ATM seems to be part of a continuum of neuroimmunologic disorders including NMO or ADEM although reasons explaining distinct focal disorders remain unclear.

Neuromyelitis optica — Devic's syndrome, update

Neuromyelitis optica of Devic (NMO) is a syndrome which combines transverse myelitis and optic neuritis. For many years it was assumed that transverse myelitis and optic neuritis should be simultaneous, that optic neuritis should be bilateral, and that transverse myelitis must be complete. NMO was considered to be very rare. Through the 20th century there was a debate on whether NMO is a distinct nosologic entity or a form of MS. In 2005 it is now possible to distinguish NMO from MS on the basis of the clinical, imaging, serology and immunopathology profile. This distinction is necessary for the implementation of adequate treatments, as the relapsing form of the illness carries significant morbidity and mortality.

Inflammatory transverse myelitis: evolving concepts

PURPOSE OF REVIEW

Acute transverse myelitis is a pathogenetically heterogeneous inflammatory disorder of the spinal cord. Here we describe recent advances in inflammatory non-infectious transverse myelitis. Particular attention will be paid to the serum autoantibody marker NMO-IgG and its application to acute transverse myelitis.

RECENT FINDINGS

The recent identification of neuromyelitis optica-IgG, a novel marker of neuromyelitis optica spectrum disorders (including longitudinally extensive transverse myelitis), contributes to an evolving understanding of acute transverse myelitis. Other serological markers, such as collapsin response-mediator protein-5 -IgG and amphiphysin-IgG, predict specific cancers in the setting of a paraneoplastic acute transverse myelitis. Furthermore, novel inflammatory markers such as interleukin-6 or other proteins in their signaling pathways may represent markers of disease severity and potential therapeutic targets. Additional cerebrospinal fluid biomarkers, such as protein 14-3-3 and neuron-specific enolase, may be useful prognostic indicators in transverse myelitis. Acute transverse myelitis in children, in contrast to adults, is more likely to be longitudinally extensive, and has a better prognosis and lower likelihood of recurrence. Prognostic factors in pediatric transverse myelitis are reviewed.

SUMMARY

The recent identification of novel biomarkers associated with acute transverse myelitis has led to a better understanding of the spectrum of disorders associated with inflammatory transverse myelitis, as well as a greater appreciation of its diverse and complex pathogenetic basis.

Characterization of the T cell receptor repertoire in the Japanese neuromyelitis optica: T cell activity is up-regulated compared to multiple sclerosis

To characterize T cell immunity in Japanese neuromyelitis optica (NMO), we examined the T cell receptor (TCR) repertoire in NMO patients with complementarity-determining region 3 (CDR3) spectratyping and compared the results with those from multiple sclerosis (MS) patients and healthy subjects. Both NMO and MS patients had a larger number of clonally expanded Vbeta genes than healthy subjects. Moreover, NMO patients had a significantly larger number of expanded Vbetas than MS patients. The detailed analysis revealed that Vbeta1 and Vbeta13 were significantly activated in NMO than MS. These results reflected unique pathophysiology of Japanese NMO, which is distinguishable from that of MS. Furthermore, longitudinal examinations of the TCR repertoire demonstrated that the number of clonally expanded Vbetas in NMO correlates with the Kurtzke Expanded disability status scale (EDSS). Although the activation pattern of the TCR repertoire in relapsing-remitting MS (RRMS) was similar to that in NMO, secondary progressive MS (SPMS) patients with longer disease durations and higher EDSS scores consistently had a smaller number of clonally expanded Vbetas than RRMS patients. Detailed TCR investigations will provide useful information to evaluate the clinical and immunological status of NMO and MS and to develop effective immunotherapies.

Diffusion tensor imaging in the assessment of normal-appearing brain tissue damage in relapsing neuromyelitis optica

BACKGROUND AND PURPOSE

Normal-appearing brain tissue (NABT) damage was established in multiple sclerosis by histology, MR spectroscopy, magnetization transfer imaging and diffusion tensor imaging (DTI). However, whether this phenomenon can be detected in relapsing neuromyelitis optica (RNMO) remains unclear. The aim of this study was to use DTI to investigate the presence of NABT damage in RNMO patients and its possible mechanism.

METHODS

Conventional MR imaging and DTI scans were performed in 16 patients with RNMO without visible lesions on brain MR imaging and in 16 sex- and age-matched healthy control subjects. Histogram analysis of mean diffusivity (MD) and fractional anisotropy (FA) was performed in the entire brain tissue (BT), white matter (WM), and gray matter (GM). Region of interest (ROI) analysis of MD and FA was also performed in WM regions connected with the spinal white matter tracts or optic nerve (including medulla oblongata, cerebral peduncle, internal capsule, and optic radiation), in corpus callosum without direct connection with them, and in some GM regions.

RESULTS

From histogram analysis, we found the RNMO group had a higher average MD of the BT, WM, and GM, a lower average MD peak height and a higher average MD peak location of the GM, and a higher average FA peak height of the WM than did the control group. From ROI analysis, compared with control subjects, RNMO patients had a higher average MD and a lower average FA in ROIs of WM connected with the spinal white matter tracts or optic nerve and a normal average MD and FA in corpus callosum without direct connection with them. In addition, a high average MD was found in parietal GM in these patients.

CONCLUSIONS

Our findings confirm the presence of abnormal diffusion in brain tissue in patients with RNMO and suggest that secondary degeneration caused by lesions in the spinal cord and optic nerve might be an important mechanism for this abnormality.

La neuromyélite optique rémittente: données neuroradiologiques

INTRODUCTION

Neuromyelitis optica (NMO) is a rare inflammatory and demyelinating disorder of the central nervous system, restricted to optical nerves and spinal cord. The main neuroradiological aspects, now summarized into a complete set of diagnosis criteria, are a normal cerebral MRI at onset and longitudinal involvement of the spinal cord concerning more than 3 vertebral segments. The clinical course and frequency of typical lesions remain unknown.

OBJECTIVE

We here report neuroradiological data from patients suffering from NMO.

METHODS

Brain and spinal cord MRI were systematically reviewed for 32 afro-Caribbean patients.

RESULTS

A typical longitudinal spinal lesion was seen in 44.7 percent with or without edema; a lesion involving less than 3 vertebral segments in 26.3 percent and no lesion in 21.1 percent. Longitudinal study of a few bouts suggested a progressive normalisation of spinal cord appearance. Atrophy was negatively correlated with immunosuppressive treatment. Cerebral lesions usually absent at onset were correlated to the follow-up. In a non-recursive condition, patients completed diagnostic criteria for encephalic and spinal lesions in 82.8 percent and 48.1 percent.

CONCLUSION

Radiology of spinal bouts showed multiple aspects besides the typical form. The notion of multiple bouts must be added to the spinal criteria to achieve good sensitivity. A typical extensive spinal lesion is usual in the follow-up, but seen after less then half of the bouts. Requiring such a lesion would delay the diagnosis.

Antibody association with a novel model for primary progressive multiple sclerosis: induction of relapsing-remitting and progressive forms of EAE in H2s mouse strains

Multiple sclerosis (MS) can be divided into 4 clinical forms: relapsing-remitting (RR), primary progressive (PP), secondary progressive (SP), and progressive relapsing (PR). Since PP-MS is notably different from the other forms of MS, both clinically and pathologically, the question arises whether PP-MS is immunologically similar to the other forms. The pathogenesis of the PP-MS remains unclear, partly due to a lack of highly relevant animal models. Using an encephalitogenic peptide from myelin oligodendrocyte glycoprotein (MOG)92-106, we have established animal models that mimic different forms of MS in 2 strains of H-2s mice, SJL/J and A.SW. We induced experimental allergic encephalomyelitis (EAE) using MOG92-106 in the presence or absence of supplemental Bordetella pertussis (BP). Although, SJL/J mice developed RR-EAE whether BP was given or not, A.SW mice developed PP-EAE without BP and SP-EAE with BP. Histologically, SJL/J mice developed mild demyelinating disease with T cell infiltration, while A.SW mice developed large areas of plaque-like demyelination with immunoglobulin deposition and neutrophil infiltration, but with minimal T cell infiltration. In A.SW mice without BP, high titer serum anti-MOG antibody was detected and the anti-MOG IgG2a/IgG1 ratio correlated with survival times of mice. We hypothesized that, in A.SW mice, a Th2 response favors production of myelinotoxic antibodies, leading to progressive forms with early death. Our new models indicate that a single encephalitogen could induce either RR-, PP-, or SP- forms of demyelinating disease in hosts with immunologically different humoral immune responses.

Neuromyelitis optica IgG predicts relapse after longitudinally extensive transverse myelitis

OBJECTIVE

We investigated whether neuromyelitis optica (NMO) IgG seropositivity at the initial presentation of longitudinally extensive transverse myelitis (LETM) predicts relapse of myelitis or development of optic neuritis.

METHODS

Prospective study of patients with initial LETM who were tested for the presence of NMO-IgG.

RESULTS

Eleven of 29 patients (37.9%) were seropositive after a first attack of LETM spanning three or more vertebral segments on magnetic resonance imaging. Of 23 patients followed up for 1 year, none of 14 who were seronegative experienced a relapse or developed optic neuritis. Of 9 seropositive patients, 5 developed a second event: 4 of 9 (44%) developed recurrent transverse myelitis and 1 of 9 (11%) developed optic neuritis (p = 0.004).

INTERPRETATION

LETM represents an inaugural or limited form of NMO in a high proportion of patients. The 40% of patients who are seropositive for NMO-IgG are at high risk for relapse.

Formes frontières de la sclérose en plaques

Multiple sclerosis (MS) has been described for more than a century, but its cause remains unknown. Numerous reports have been written concerning borderline types of the disease. In the present paper we present the pseudo-tumoral variants of MS (so called Balo's, Marburg's and Schilder's forms), demographic variants (young and elderly onset of MS), related disorders (neuromyelitis optica and acute demyelinating encephalomyelitis). We also discuss the differential diagnosis with other auto-immune diseases.

La neuromyélite optique au Maroc

INTRODUCTION

Optic neuromyelitis or Devic's syndrome associates optic neuritis and myelitis. It can have a monophasic or relapsing course. The limits of this entity remain controversial.

METHODS

We analyzed the results of a retrospective series of Moroccan patients with Devic's syndrome defined on the basis of Wingerchuk's criteria.

RESULTS

Six women and three men were retained for study; average age was 39 years. Three patients presented with a monophasic form and six with relapsing disease. CSF analysis was abnormal in five. Brain MRI was normal in eight. Signal abnormalities extended over more than three vertebrae in eight patients. Infections were associated with neurological features in half of the patients.

DISCUSSION

Our results are in agreement with those of large series in the literature regarding the clinical, imaging, and laboratory findings and disease course. We also noted that infections were more frequently associated with Devic's syndrome in our patients.

CONCLUSION

Our study reports the results of the first North African series of Devic's syndrome patients. We suggest that this syndrome is particular in our context due to the high frequency and diversity of associated infections.

Successful high dose glucocorticoid treatment for subacute neuromyelitis optica with systemic lupus erythematosus

A 54-year-old Japanese woman with a 6-year history of systemic lupus erythematosus (SLE) was admitted to our hospital suffering from acute blindness in her right eye. Her condition recovered after steroid pulse therapy, however, 18 months later she suffered from nuchal pain for 2 weeks after which right hemiparesis with urinary incontinence developed. A spinal magnetic resonance imaging (MRI) revealed cord swelling from C2 to C7. She was diagnosed with neuromyelitis optica (NMO) and intravenous steroid administrations were immediately commenced. Her condition promptly improved. This case was unique because the steroid treatment was quite effective for this case of myelitis, which had passed the acute phase. We supposed that, because most of the lesion was not necrotic or demyelinated, but rather showed edematous change caused by vasculitis based on autoimmune pathogenesis, the symptoms progressed rather gradually and improved promptly in response to glucocorticoid treatment.

Activation of humoral immunity and eosinophils in neuromyelitis optica

OBJECTIVE

To study immunologic alterations in patients with neuromyelitis optica (NMO).

METHODS

The authors studied 8 patients with NMO together with 16 healthy subjects, 16 patients with relapsing remitting multiple sclerosis (RRMS), and 16 patients with secondary progressive MS (SPMS), matched for age and sex, as controls. Because recent histopathologic studies have demonstrated that active NMO lesions consist of perivascular immunoglobulin (Ig) deposition and eosinophil infiltration, IL-5, IL-6, IL-12, IgG, and IgM production by anti-myelin oligodendrocyte glycoprotein (MOG) mononuclear cells in peripheral blood and CSF were selected for study using ELISPOT. Eotaxin-2 (Eo-2) and eotaxin-3 (Eo-3) levels were also assessed using ELISA and eosinophil cationic protein (ECP) levels by radioimmunoassay.

RESULTS

MOG-specific responses in CSF showed significant increase in IL-5, IL-6, IgG, and IgM secreting cells in NMO patients compared with patients with RRMS, SPMS and healthy subjects. Interestingly, numbers of IgM secreting cells were significantly higher than identical specificity IgG secreting ones. Moreover, CSF Eo-2, Eo-3, and ECP levels were also significantly higher in NMO patients compared to all three control populations. Anti-MOG IL-12 secreting cells were increased in CSF and peripheral blood from NMO, RRMS, and SPMS patients when compared to healthy subjects.

CONCLUSIONS

These observations suggest that neuromyelitis optica is associated with a major humoral immune response (particularly anti-MOG IgM production) and eosinophil activation present exclusively in CSF.