Sex bias in multiple sclerosis and neuromyelitis optica spectrum disorders: How it influences clinical course, MRI parameters and prognosis

This review is a condensed summary of representative articles addressing the sex/gender bias in multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD). The strong effects of sex on the incidence and possibly also the activity and progression of these disorders should be implemented in the evaluation of any phase of clinical research and also in treatment choice consideration in clinical practice and evaluation of MRI parameters. Some relationships between clinical variables and gender still remain elusive but with further understanding of sex/gender-related differences, we should be able to provide appropriate patient-centered care and research.

Neuropsychiatric Manifestations of Antiphospholipid Syndrome—A Narrative Review

Antiphospholipid syndrome (APS) is a common autoimmune pro-thrombotic condition characterised by thrombosis and pregnancy morbidity. There are a broad range of neuropsychiatric manifestations associated with APS, from focal symptoms to more global dysfunction. Patients commonly present with transient ischaemic attacks and ischaemic strokes, with identifiable lesions on brain imaging. However, the underlying pathogenesis remains uncertain in other manifestations, such as cognitive dysfunction, seizures, headache and chorea. The aim is to provide a comprehensive review of the various neuropsychiatric manifestations associated with APS. A detailed literature search was applied to PubMed, including citations from 1983 to December 2021.

Autoimmune diseases associated with Neuromyelitis Optica Spectrum Disorders: A literature review

INTRODUCTION

Neuromyelitis Optica (NMO) is an autoimmune inflammatory demyelinating disease of the central nervous system (CNS) which predominantly involves optic nerves and spinal cord. Since the introduction of Neuromyelitis Optica Spectrum Disorders (NMOSD) as a separate entity, there have been many reports on its association with other disorders including systemic and organ-specific autoimmune diseases. Here, we reviewed other immune-mediated diseases associated with NMOSD and tried to categorize them.

METHODS

The present review was conducted using the PUBMED database based on papers from 1976 (i.e., since the first NMO comorbidity with SLE was reported) to 2017. We included all articles published in English. The keywords utilized included Neuromyelitis optica, Neuromyelitis Optica Spectrum Disorders, Devic's disease, in combination with comorbidity or comorbidities.

RESULTS

Diseases with immune-based pathogenesis are the most frequently reported co-morbidities associated with NMOSD, most of which are antibody-mediated diseases. According to literature, Sjogren's Syndrome (SS) and Systemic Lupus Erythematosus (SLE) are the most frequently reported diseases associated with NMOSD among systemic autoimmune diseases. Further, myasthenia gravis in neurological and autoimmune thyroid diseases in non-neurological organ-specific autoimmune diseases are the most reported comorbidities associated with NMOSD in the literature.

CONCLUSIONS

NMOSD may be associated with a variety of different types of autoimmune diseases. Therefore, systemic or laboratory signs which are not typical for NMOSD should be properly investigated to exclude other associated comorbidities. These comorbidities may affect the treatment strategy and may improve the patients' care and management.

Aquaporin-4-autoimmunity in patients with systemic lupus erythematosus: A predominantly population-based study

BACKGROUND

Serum immunoglobulin G targeting the astrocyte water channel aquaporin-4 (AQP4) in the central nervous system (CNS) is a biomarker for neuromyelitis optica spectrum disease (NMOSD). Co-existence of NMOSD with systemic lupus erythematosus (SLE) putatively suggests susceptibility to antibody-mediated autoimmune disease.

OBJECTIVE

To estimate the prevalence of NMOSD in SLE and investigate the immunogenetic background for an association of NMOSD and SLE.

METHODS

The study included a predominantly population-based cohort with clinical and serological investigations of 208 patients with SLE, followed prospectively since 1995. All patients received immunosuppressive treatment. NMOSD was evaluated retrospectively based on the 2015 International Panel for NMOSD Diagnosis (IPND) criteria. Polymorphisms in programmed cell death protein 1 (PDCD-1) PD-1.3 G/A were genotyped. AGP4-IgG and other autoantibodies, including myelin oligodendrocyte glycoprotein (MOG), was determined blinded to clinical diagnosis.

RESULTS

Of 208 patients with SLE, 45(22%) had neuropsychiatric (NP) SLE, and CNS involvement predominated in 30 of 45 (67%) patients. Serum AQP4-IgG was detected in 2 of 30 (6.7%) neuropsychiatric SLE (NPSLE) patients both of whom had myelitis and antiphospholipid syndrome; one patient also had myasthenia gravis. None had MOG-IgG. PD-1.3A allele was not associated with SLE nor with NPSLE.

CONCLUSION

AQP4-IgG autoimmune syndrome may rarely co-exist with SLE, and such patients have other NMOSD-typical syndromes such as myelitis.

Th17 cells in neuromyelitis optica spectrum disorder: a review

Neuromyelitis optica spectrum disorder (NMOSD) has been identified as a central nervous system (CNS) autoimmune inflammatory disorder, which has been recognized as a B cell-mediated humoral immune disease. However, cases have been reported indicating that some of the neuromyelitis optica (NMO) patients have been resistant to B cell-related treatments. Recently, more and more evidence has shown that T cell-mediated immunity may take part in the pathogenesis of NMOSD, especially in the Th17 phenotype. In our PUBMED search, we used the following keywords: Th17 cell, Th17 cell-related cytokines, T cells, B cells, B cell-related productions, NMO, NMOSD, recurrent/bilateral optic neuritis, recurrent transverse myelitis and longitudinally extensive transverse myelitis. We systemically reviewed the role of Th17 cells and Th17 cell-related cytokines in NMOSD. We found that Th17 cells and Th17-related cytokines, such as IL-6, IL-1β, IL-17, IL-21, IL-22, IL-23 and TGF-β, are not only directly involved in the pathogenesis but also collaborated with B cells and B cell-related antibody production to induce CNS lesions. Th17 cell-related therapy has also been reviewed in this article, and the data suggested that Th17 may be a new therapeutic target of NMOSD.

[Contribution of spinal cord biopsy to the differential diagnosis of longitudinal extensive transverse myelitis]

BACKGROUND

Neuromyelitis optica spectrum disorders (NMOSD) are characterized by recurrent optic neuritis (ON) and longitudinally extensive transverse myelitis (LETM) as well as the serological detection of antibodies to aquaporin-4 (AQP4-ab). However, longitudinal extensive spinal cord lesions are not pathognomonic for NMOSD as they can also occur in systemic autoimmune diseases or mimic spinal cord tumors.

OBJECTIVES/METHODS

We report a female patient who initially presented with a subacute spinal syndrome and a longitudinal spinal cord lesion on magnetic resonance imaging (MRI). As the brain MRI showed only unspecific white matter lesions and the cerebrospinal fluid was normal, a spinal cord biopsy was performed to exclude malignancies and revealed inflammatory demyelinating changes. In addition, after several deep vein thromboses and the detection of antiphospholipid antibodies, an antiphospholipid syndrome (APS) was diagnosed. Many years after the spinal cord biopsy, AQP4-ab were tested and found to be positive. We discuss the important differential diagnoses of LETM, give an overview of previously reported NMOSD cases in which a spinal cord biopsy was performed and highlight the crucial role of AQP4-ab testing for the differential diagnosis of longitudinal spinal cord lesions.

RESULTS/CONCLUSIONS

Considering possible serious sequelae of spinal biopsy procedures, testing for AQP4-ab is mandatory in patients with unclear longitudinally extensive spinal cord lesions and should be performed preoperatively in all cases. In light of the heterogeneity of available assays, different detection methods should be used in doubtful cases. The relationship between NMO and APS needs further clarification; however, AQP4 IgG testing is recommended in patients presenting with APS and myelitis, optic neuritis or brainstem encephalitis.

An approach to differential diagnosis of antiphospholipid antibody syndrome and related conditions

The antiphospholipid antibody syndrome is a systemic, acquired, immune-mediated disorder characterized by episodes of venous, arterial, or microcirculation thrombosis and/or pregnancy abnormalities, associated with the persistent presence of autoantibodies, confirmed at least in two occasions 12 weeks apart, directed to molecular complexes consisting of phospholipids and proteins. Antiphospholipid antibody syndrome should always be considered as a potential diagnosis especially for young patients presenting with a history of thrombotic events, in particular when they occur without any obvious external trigger or any inherited thrombophilic mutation (even if 2006 criteria do not exclude antiphospholipid antibody syndrome in patients with other inherited or acquired prothrombotic conditions), or for women with recurrent pregnancy losses or later fetal deaths. Many other disorders are able to mimic antiphospholipid antibody syndrome, so a broad range of alternative diagnoses should be investigated and ruled out during clinical workup.

Semiquantitative measurement of aquaporin-4 antibodies as a possible surrogate marker of neuromyelitis optica spectrum disorders with systemic autoimmune diseases

OBJECTIVES

To assess the association between serum aquaporin-4 (AQP4) autoantibodies and neuromyelitis optica spectrum disorders (NMOSDs) associated with systemic autoimmune diseases.

METHODS

We retrospectively studied 626 hospitalized patients with systemic lupus erythematosus (SLE) or Sjögren's syndrome (SS). We collected serum samples from those patients with suspected NMOSDs (i.e., myelitis or optic neuritis) at the time of onset and thereafter. AQP4 antibodies were measured by a cell-based indirect immunofluorescence assay using AQP4-transfected HEK-293 cells in a semi-quantitative manner.

RESULTS

Sera from 6 patients with suspected NMOSDs and SLE (n = 3) or SS (n = 3) were evaluated. Among these, 2 patients' sera samples, i.e., 1 with SLE and 1 with SS, were positive for AQP4 antibodies. There was an inverse relationship between disease amelioration and antibody titer in one NMOSD patient, whereas the antibody titer remained high in the other NMOSD patient, whose clinical manifestations of NMOSDs did not improve despite intensive immunosuppressive treatments.

CONCLUSIONS

These results indicate that serum AQP4 antibodies are present in some SLE/SS patients with myelitis/optic neuritis and might be associated with clinical outcomes. The semi-quantitative measurement of the AQP4 antibody might be a possible surrogate marker in patients with NMOSDs associated with systemic autoimmune diseases.

Devic's syndrome and SLE: challenges in diagnosis and therapeutic possibilities based on two overlapping cases

Neuromyelitis optica (NMO, Devic's disease), an uncommon demyelinating neuro-immunological disease, can be associated with autoimmune diseases. In SLE associated forms anti-aquaporin-4 antibody positivity can help differentiating between SLE nerve system manifestation and NMO. In the literature rituximab, or immunoablative dose cyclophosphamide (CYC) was effective for the therapy resistant forms. Authors present 2 SLE overlapping NMO cases, one of them with SLE associated interstitial lung disease (ILD). In both cases neurological manifestations anticipated other SLE symptoms. Patients previously were treated with high dose corticosteroid therapy, plasmapheresis, and one of them with azathioprine, and the other one with oral CYC (which could not prevent flares). 0.5 g/m² body-surface monthly parenteral inductive CYC therapy was administered, in one patient followed by quarterly maintenance therapy. This patient completed her 18 month maintenance treatment and has been in neurological remission, but required steroid pulse and plasmapheresis for lung symptoms. The second patient had urogenital infection after the induction phase, followed by an exacerbation, requiring plasmapheresis and high dose parenteral corticosteroid treatment. After it he refused CYC therapy and has been taking azathioprine. He has no new symptoms, only residual ones. In our two patients conventional dose CYC therapy proved to be effective for NMO/SLE overlap, required only transient supportive therapy.