Recurrent transverse myelitis, myasthenia gravis, and autoantibodies

Clinical characteristics of autoimmune disorders in the central nervous system associated with myasthenia gravis

Myasthenia gravis (MG) is occasionally associated with autoimmune diseases in the central nervous system (CNS), such as neuromyelitis optica spectrum disorder (NMOSD), multiple sclerosis (MS), Morvan syndrome, and anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. Here, we report five original cases associated with autoimmune disorders in the CNS among 42 patients with MG in a single tertiary hospital in Japan (11.9%). In four of these five cases, the second disease developed when the preceding disease was unstable. Accurate diagnosis of the newly developing disease may be difficult in such cases, because some neurological symptoms can be seen in both disorders. This implies the great importance of recognizing the possible co-occurrence of MG and disorders in the CNS. In addition, a comprehensive review of the literature revealed distinct clinical characteristics depending on the associated disease in the CNS, including thymic pathology and temporal relationship between MG and associated CNS disorders. Notably, NMOSD usually develops after the onset of MG and thymectomy, in clear contrast to MS. Thymoma is highly prevalent among patients with Morvan syndrome, in contract to cases with NMOSD and MS. The analysis of clinical characteristics, representing the first such investigation to the best of our knowledge, suggests different pathogeneses of these autoimmune diseases in the CNS, and provides significant implications for clinical practice.

Myasthenia gravis and neuromyelitis opica: A causal link

Neuromyelitis Optica (NMO) and Myasthenia Gravis (MG) are rare antibody mediated disorders of the central nervous system (CNS) and neuromuscular junction (NMJ) respectively. Both diseases are predominantly mediated by IgG1 antibodies that activate complement. There have been increasing reports of patients who develop both disorders. Given the rarity of both diseases it would seem that these occurrences are not purely coincidental. There is heterogeneity between the cases described in the literature but common trends are observed in patients who develop both disorders. Most patients described are female. Typically the MG precedes the NMO and the majority of patients have undergone thymectomy. Generally, the symptoms of MG are mild but the NMO tends to follow a more aggressive clinical course. The pathogenesis of NMO in combination with MG is unknown, but thymectomy has been implicated in a subset of patients. We present the case of a female patient who developed NMO on a background of sero-positive MG and discuss the relevant literature.

Myasthenia gravis development and crisis subsequent to multiple sclerosis

During the last decade, sporadic combination of multiple sclerosis (MS) and myasthenia gravis (MG) has been reported repeatedly. Although these are anecdotal, they are important enough to raise concerns about co-occurrence of MG and MS. Here, we present a case of an MS patient who developed an MG crisis. She had received interferon for relapsing remitting MS. Interestingly, she developed an MG crisis 4 years after the diagnosis of MS. MS and MG have relatively the same distribution for age, corresponding to the younger peak of the bimodal age distribution in MG. They also share some HLA typing characteristics. Furthermore, some evidences support the role of systemic immune dysregulation due to a genetic susceptibility that is common to these two diseases. The association may be underdiagnosed because of the possible overlap of symptoms especially bulbar manifestations in which either MG or MS can mimic each other, leading to underestimating incidence of the combination. The evidence warrants physicians, especially neurologists, to always consider the possibility of the other disease when encountering any patients either with MS or MG. Anecdotal and sporadic reports of combination of multiple sclerosis (MS) and myasthenia gravis (MG) have been raised concerns about co-occurrence of them.

Demyelinating disease in patients with myasthenia gravis

Myasthenia gravis (MG) is an autoimmune disease characterized by fluctuating muscle weakness, caused by impaired neuromuscular transmission. Patients with MG can present other autoimmune diseases in association, commonly hypo or hyperthyroidism. The association of MG to demyelinating disease is rare and has been described before. We report on three Brazilian patients with MG that presented distinct demyelinating diseases, two monophasic and one recurrent neuromyelitis optica, several years after the diagnosis of MG, and discuss their clinical courses.

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 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.

Relapsing acute transverse myelitis: a specific entity

Acute transverse myelitis (ATM) not related to systemic disease may present in a relapsing manner. Data in the literature about this condition are scarce. We describe three patients suffering from relapsing myelitis in whom no association with systemic disease, i.e. infectious or connective tissue disease was found. Magnetic resonance imaging (MRI) findings were also distinctly different from multiple sclerosis and consistent with a necrotizing type of inflammation. Despite various treatment strategies, all patients became severely disabled. Relapsing ATM not related to systemic disease appears to be a specific entity which accounts for severe disability and currently lacks effective treatment.

Myélopathies aiguës transverses : myélopathie inflammatoire ou ischémique ?

The rapid development of paraparesis or tetraparesis combined with a bilateral sensory deficit that has a clearly defined rostral border and bladder dysfunction are the principal features of acute transverse myelopathy. Acute partial transverse myelopathy is far much more frequent: its symptoms are asymmetric, sometimes unilateral, and sensory deficit may predominate. An urgent MRI is required to exclude acute spinal cord compression. Diagnosis of ischemic acute transverse myelopathy includes the following elements: sudden onset, neurologic symptoms compatible with infarction in the anterior spinal artery area (by far the most frequent location for spinal cord infarction), and presence of a specific cause of spinal cord ischemia. In all other cases where it is difficult to distinguish spinal cord infarction from myelitis, analysis of the cerebrospinal fluid is essential. Most cases of inflammatory acute transverse myelopathy can be linked to a defined cause. Multiple sclerosis is a major cause of partial acute transverse myelopathy. MRI lesions are usually small, located in the lateral or posterior part of the spinal cord. Diagnostic elements include multiple lesions of multifocal demyelination on the cerebral MRI, oligoclonal bands in the cerebrospinal fluid, and the absence of clinical or laboratory abnormalities that suggest systemic disease. Neuromyelitis optica, also known as Devic's disease, has often been considered a variant form of multiple sclerosis. Recent immunologic studies confirm the hypothesis that it is a distinct entity. Infectious transverse acute myelitis is often of viral origin. It may result from direct viral stress but more frequently follows immunologically-mediated indirect stress. This acute parainfectious myelitis, like postvaccinal myelitis, may be considered as a spinal single-focus form of acute disseminated encephalomyelitis (ADEM). It is important to distinguish the latter from an initial episode of multiple sclerosis, because their prognosis and treatment differ.

A role for humoral mechanisms in the pathogenesis of Devic's neuromyelitis optica

Devic's disease [neuromyelitis optica (NMO)] is an idiopathic inflammatory demyelinating disease of the CNS, characterized by attacks of optic neuritis and myelitis. The mechanisms that result in selective localization of inflammatory demyelinating lesions to the optic nerves and spinal cord are unknown. Serological and clinical evidence of B cell autoimmunity has been observed in a high proportion of patients with NMO. The purpose of this study was to investigate the importance of humoral mechanisms, including complement activation, in producing the necrotizing demyelination seen in the spinal cord and optic nerves. Eighty-two lesions were examined from nine autopsy cases of clinically confirmed Devic's disease. Demyelinating activity in the lesions was immunocytochemically classified as early active (21 lesions), late active (18 lesions), inactive (35 lesions) or remyelinating (eight lesions) by examining the antigenic profile of myelin degradation products within macrophages. The pathology of the lesions was analysed using a broad spectrum of immunological and neurobiological markers, and lesions were defined on the basis of myelin protein loss, the geography and extension of plaques, the patterns of oligodendrocyte destruction and the immunopathological evidence of complement activation. The pathology was identical in all nine patients. Extensive demyelination was present across multiple spinal cord levels, associated with cavitation, necrosis and acute axonal pathology (spheroids), in both grey and white matter. There was a pronounced loss of oligodendrocytes within the lesions. The inflammatory infiltrates in active lesions were characterized by extensive macrophage infiltration associated with large numbers of perivascular granulocytes and eosinophils and rare CD3(+) and CD8(+) T cells. There was a pronounced perivascular deposition of immunoglobulins (mainly IgM) and complement C9neo antigen in active lesions associated with prominent vascular fibrosis and hyalinization in both active and inactive lesions. The extent of complement activation, eosinophilic infiltration and vascular fibrosis observed in the Devic NMO cases is more prominent compared with that in prototypic multiple sclerosis, and supports a role for humoral immunity in the pathogenesis of NMO. Based on this study, future therapeutic strategies designed to limit the deleterious effects of complement activation, eosinophil degranulation and neutrophil/macrophage/microglial activation are worthy of further investigation.

[Myelopathy revealing lupus. Two cases and review of the literature]

INTRODUCTION

Myelopathy is a rare manifestation of systemic lupus erythematosus, occurring most often during the course of the disease.

EXEGESIS

We report two cases of women with myelopathy as the first manifestation of systemic lupus erythematosus; both had an unusual course. We review the literature for previously reported cases.

CONCLUSION

The clinical presentation of myelitis is heterogeneous. Usually, neurologic deficits evolve within a few hours (typically acute transverse myelitis) and outcome is usually poor. However, chronic or recurrent transverse myelitis has also been reported, including relapsing myelitis that resolved spontaneously. Myelopathy can be the first manifestation of the disease and this might be more common than initially thought. Magnetic resonance imaging (MRI) findings depend on the timing of the examination and the stage of the disease; the MRI may therefore be normal. An association with optic neuritis is frequently reported in the literature and differential diagnosis with multiple sclerosis may be difficult. Overlapping features between both diseases have been termed "lupoid sclerosis" and are actually classified as demyelinating syndromes associated with lupus. Myelopathy does not appear to be consistently associated with antiphospholipid antibodies, as has been previously suggested. The best treatment protocol has not been determined; however, in recent years, pulses of methylprednisolone and cyclophosphamide have gained acceptance by most authors.

Recurrent myelitis

Three patients presented with acute complete transverse myelopathy which relapsed several times at the same site. These patients, two women and one man, had two to five attacks spanning three to seven years. All patients underwent detailed investigations including a complete myelogram and serial evoked potential studies. Oligoclonal bands were present in the CSF in one patient. Brain MRI was normal in two patients; MRI of the spinal cord was abnormal and showed cord oedema with multiple areas of hyperintense signals on T2 and proton density weighted scans and hypointense signals on T1 weighted images in areas corresponding to the clinical level, suggesting an inflammatory/demyelinating disorder. These patients may represent a relapsing demyelinating disorder restricted to the spinal cord, distinct from multiple sclerosis.

Myasthenia gravis, acute transverse myelitis, and HTLV-I

We present the unusual case of a 49-year-old female carrier of HTLV-I with myasthenia gravis who presented with acute transverse myelitis. Laboratory data suggested a recent infection with varicella zoster virus and demyelination by an autoimmune process in the central nervous system. Adult T-cell leukemia-like cells were observed in the cerebrospinal fluid. T-cell-mediated immune responses modulated by HTLV-I infection may be involved in the pathogenesis of myasthenia gravis and acute transverse myelitis in this case.

Immunogenetic heterogeneity and associated autoimmune disorders in myasthenia gravis: a population-based survey in the province of Ferrara, northern Italy

INTRODUCTION

The well-established relationship between myasthenia gravis (MG) and HLA antigens varies among different ethnic groups. In Caucasians B8 and/or DR3 alleles have been found associated with young MG women without thymoma and with high titres of acetylcholine-receptor antibody (AChR Ab). An increased frequency of haplotype HLA-A3, B7 and/or DR2 has been observed in older MG patients with low AChR Ab levels. So far, there is no convincing evidence for an association between a specific haplotype HLA and ocular MG or MG with thymoma. MG subjects often show other concurrent autoimmune disorders suggesting a more general inherited predisposition to autoimmunity. We performed a community-based study to verify the HLA-A, B, C, DR and DQ profile on ethnically homogeneous MG patients and with the aim to estimate the frequency of concurrent autoimmune diseases and to compare HLA phenotypes to autoimmune status in different MG patients groups.

METHODS

Forty-seven patients, living in the province of Ferrara, were followed-up in our neurologic department and typed for HLA Antigens. In addition a set of immunological laboratory tests was performed.

RESULTS

We found a trend towards an increased B8 and DR3 frequencies in total affected population; an association between B8 allele and early onset of generalized MG sustained by thymic hyperplasia. The DR3 allele is statistically associated with the presence of additional autoimmune disorders.

CONCLUSIONS

Our data support the hypothesis of a genetically-based heterogeneity of the disease and show an increased prevalence of associate autoimmune conditions in MG patients.

Recurrent opticomyelitis associated with anti-DNA antibody

Two patients had frequent attacks of acute myelitis and optic neuritis. One patient lacked any other organ involvement whereas the other developed systemic manifestations of systemic lupus erythematosus 14 years after the onset. Both patients developed antinuclear and antidouble strand DNA antibodies after the onset of neurological involvement. These patients, whose neurological manifestations were indistinguishable from multiple sclerosis, were thus considered to have systemic lupus erythematosus related collagen disease.