anti-AQP4 Antibody Research Articles

Efficacy and Safety of Inebilizumab, an Anti-CD19 Monoclonal Antibody, for the Treatment of Neuromyelitis Optica Spectrum Disorder: Based on the N-MOmentum Trial

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune astrocytopathic disease of the central nervous system characterized by severe optic neuritis and transverse myelitis. The antibody against aquaporin 4 (AQP4), a water channel mainly expressed in astrocytes, is specific to NMOSD and may be detected in >70% of all cases. Inebilizumab is a humanized IgG1 monoclonal antibody against CD19. Anti-AQP4 antibodies are produced by CD19-positive plasmablasts, and inebilizumab administration significantly reduces the number of CD19-positive B cells and has therapeutic effects on NMOSD. The efficacy and safety of inebilizumab have been verified in the N-MOmentum trial, an international double-blind, placebo-controlled phase II/III study, in which Japanese patients also participated. Inebilizumab was approved for the treatment of NMOSD with AQP4-IgG in Japan in March 2021. In this review, we summarize the efficacy and safety of inebilizumab in the treatment of NMOSD and, focus on findings from the primary and additional analyses of the N-MOmentum trial. These results suggest that inebilizumab is effective and safe in preventing the recurrence of NMOSD in populations with different backgrounds and that long-term treatment with inebilizumab is beneficial.

Aquaporin-4 IgG Antibody Detection in Neuromyelitis Optic Spectrum Disorder

Objective: To develop a sensitive and reliable diagnostic approach for optic neuromyelitis (ONM), an overexpressing cell line capable of detecting aquaporin 4 (AQP4) antibodies was established. Subsequently, immunofluorescence was employed to detect AQP4 antibodies in serum and cerebrospinal fluid (CSF) samples from patients. Additionally, the clinical utility of AQP4 antibodies in the detection of ONM patients was analyzed. Methods: An aquaporin 4 expression plasmid was constructed and transfected into cell lines. Subsequently, indirect immunofluorescence was utilized to detect anti-AQP4 antibodies in serum and cerebrospinal fluid samples. Results: The indirect immunofluorescence detection system exhibited high sensitivity in the detection of 2241 clinical samples, with a positive rate of 16.8%. The positive proportion was in line with epidemiological data, and the positive situation was consistent with clinical symptoms. Conclusion: The engineered cell line exhibits superior detection performance for identifying antibodies present in serum and cerebrospinal fluid samples. The capability to detect anti-aquaporin 4 antibodies is pivotal for improving the efficiency of screening and diagnosing neuromyelitis optica, thereby possessing considerable potential for clinical application.

Clinical spectrum of demyelinating disease of central nervous system and frequency of anti AQP4 and anti MOG among them: one-year single-center retrospective study

Background: Inflammatory demyelinating diseases of the central nervous system (CNS) are autoimmune conditions leading to significant neurological disability in adults. Recent classifications include myelin oligodendrocyte glycoprotein antibody associated disease (MOGAD) and neuromyelitis optica spectrum disorder (NMOSD) which pose diagnostic challenges due to overlapping clinical and radiological features. This study aimed to assess the clinical spectrum among adults and children diagnosed with CNS demyelinating diseases and to find the proportion of MOG and/or aquaporin-4 (AQP4) autoantibodies amongst them. Methods: This single-center, retrospective study examined 20 patients diagnosed with CNS demyelinating disorders between March, 2023 and February, 2024. Data pertaining to demographics, disease types, CSF analysis, MRI findings, treatment modalities, and serological profiles for anti-AQP4 and anti-MOG antibodies were collected from hospital records and evaluated. Results: Among 20 patients [median age, 34 years (IQR, 18.75); males (n=10) and females (n=10)], acute transverse myelitis (TM) was the most common demyelinating disorder at onset (60%) followed by optic neuritis (ON) (20%). CSF analysis found elevated protein levels in 53% and pleocytosis in 33% of patients. MRI findings revealed longitudinal extensive involvement in 52% of patients, predominantly affecting the cervical and dorsal spine. Serological testing identified 15% positive for anti-AQP4 and 10% for anti-MOG antibodies. MOG+ patients were significantly younger than AQP4+ patients (mean age 16.5 vs. 36.66 years, p=0.016). Both MOG+ patients were male, with 50% presenting with acute TM and 50% with acute disseminated encephalomyelitis. Among AQP4+ patients, the male-to-female ratio was 1:2, with 66.66% presenting with acute TM and 33.33% with ON. Conclusion: CNS demyelinating disorders primarily affect younger individuals, with TM as the most common initial disorder and extensive spinal involvement in cervical and dorsal regions. Serological testing identified three patients with anti-AQP4 and two with anti-MOG antibodies, providing valuable insights into the clinical spectrum of these disorders through cell-based assays.

Pure spinal multiple sclerosis: A case series of a possible new entity

BackgroundRecent literature describes a condition similar to multiple sclerosis (MS) but with demyelinating lesions limited to the spinal cord. This condition, referred to as “pure spinal” MS, might benefit from disease-modifying treatment (DMT). MethodsWe screened the medical records of approximately 8000 patients with demyelinating diseases at the Isfahan MS clinic in Iran. Criteria for inclusion in the case series were adults with a demyelinating disease limited to the spinal cord, positive oligoclonal IgG bands in cerebrospinal fluid (CSF), and negative results for other potential diagnoses. ResultsSeven people with pure spinal MS were identified (all women, mean age [SD]: 40.14 [6.17] years at the first visit, mean follow-up duration [SD]: 98 [39.41] months). Two had a family history of conventional MS in their siblings. All patients exhibited lower limb weakness and tested negative for anti-MOG and anti-AQP4 antibodies. They experienced relapsing-remitting partial myelitis, with new spinal cord lesions on MRI but no extraspinal CNS lesions. DMT significantly reduced relapse rates in all patients, and two showed no increase in EDSS scores. ConclusionPure spinal MS might be an atypical form of MS. Those affected may benefit from DMT; therefore, further investigation and consideration in the upcoming revisions of the McDonald criteria are recommended.

Whole spinal transverse myelitis in neuromyelitis optica spectrum disorder

Background: Spinal cord is one of the prominent targets of autoimmune mechanisms in Neuromyelitis Optica Spectrum Disorder (NMOSD). Rarely, NMOSD causes damage to the entire length of the spinal cord, from cervical segments to conus medullaris, which has not been characterized in the existing literature.Material and method: We reviewed medical records, demographic information, and magnetic resonance imaging (MRI) sequences of 174 NMOSD patients from January 2011 to January 2023 who were admitted to Isfahan Multiple Sclerosis center to find patients with whole spinal transverse myelitis (TM).Results: Whole spinal TM was present in five patients (2.9 %). Three patients were seropositive for Aquaporin-4 (AQP4) antibody; Myelin Oligodendrocyte Glycoprotein antibody (MOG IgG) tested negative for all of them. Lower limb weakness was the most frequent clinical complaint. Two patients presented with optic neuritis; One patient reported having episodes of nausea and vomiting. These patients, overall, yielded a higher expanded disability status scale (EDSS) score than the other NMOSD patients.Conclusion: Whole spinal TM is a rare finding in NMOSD, which is strongly associated with a higher severity and a worse outcome of the disease. The role of anti-AQP4 antibodies in the extent of myelitis in NMOSD has yet to be investigated.

Stage-dependent immunity orchestrates AQP4 antibody-guided NMOSD pathology: a role for netting neutrophils with resident memory T cells in situ.

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune disease of the CNS characterized by the production of disease-specific autoantibodies against aquaporin-4 (AQP4) water channels. Animal model studies suggest that anti-AQP4 antibodies cause a loss of AQP4-expressing astrocytes, primarily via complement-dependent cytotoxicity. Nonetheless, several aspects of the disease remain unclear, including: how anti-AQP4 antibodies cross the blood-brain barrier from the periphery to the CNS; how NMOSD expands into longitudinally extensive transverse myelitis or optic neuritis; how multiphasic courses occur; and how to prevent attacks without depleting circulating anti-AQP4 antibodies, especially when employing B-cell-depleting therapies. To address these knowledge gaps, we conducted a comprehensive 'stage-dependent' investigation of immune cell elements in situ in human NMOSD lesions, based on neuropathological techniques for autopsied/biopsied CNS materials. The present study provided three major findings. First, activated or netting neutrophils and melanoma cell adhesion molecule-positive (MCAM+) helper T (TH) 17/cytotoxic T (TC) 17 cells are prominent, and the numbers of these correlate with the size of NMOSD lesions in the initial or early-active stages. Second, forkhead box P3-positive (FOXP3+) regulatory T (Treg) cells are recruited to NMOSD lesions during the initial, early-active or late-active stages, suggesting rapid suppression of proinflammatory autoimmune events in the active stages of NMOSD. Third, compartmentalized resident memory immune cells, including CD103+ tissue-resident memory T (TRM) cells with long-lasting inflammatory potential, are detected under "standby" conditions in all stages. Furthermore, CD103+ TRM cells express high levels of granzyme B/perforin-1 in the initial or early-active stages of NMOSD in situ. We infer that stage-dependent compartmentalized immune traits orchestrate the pathology of anti-AQP4 antibody-guided NMOSD in situ. Our work further suggests that targeting activated/netting neutrophils, MCAM+ TH17/TC17 cells, and CD103+ TRM cells, as well as promoting the expansion of FOXP3+ Treg cells, may be effective in treating and preventing relapses of NMOSD.

Establishment of novel cell lines that maintain the features of B cells derived from patients with neuromyelitis optica spectrum disorder

B cells that produce anti–aquaporin-4 (AQP4) antibodies play a crucial role in neuromyelitis optica spectrum disorder (NMOSD) pathogenesis. We previously reported that naïve B (NB) cells from patients with NMOSD, unlike those from healthy controls, exhibit transcriptional changes suggesting the adoption of an antibody-secreting cell (ASCs) phenotype. CD25+ NB cells, whose numbers are increased in NMOSD patients, have a greater capacity to differentiate into ASCs than do CD25- NB cells. Here, we attempted to establish novel B cell subset cell lines from patients with NMOSD to enable molecular analysis of their abnormalities. We generated Epstein-Barr virus–immortalized lymphoblastoid cell lines (LCLs) from CD25+ NB, CD25- NB, and switched memory B (SMB) cells. All LCLs largely maintained the features of the original cell type in terms of cell surface marker expression and could differentiate into ASCs. Notably, CD25+ NB–LCLs derived from patients with NMOSD exhibited a greater capacity to differentiate into SMB-LCLs than did CD25- NB–LCLs derived from patients with NMOSD, suggesting that the established LCLs maintained the characteristics of cells isolated from patients. The LCLs established in this study are likely to be useful for elucidating the mechanism by which cells that produce anti-AQP4 antibodies develop in NMOSD.

Clinical Research into Central Nervous System Inflammatory Demyelinating Diseases Related to COVID-19 Vaccines.

Various vaccines have been developed in response to the SARS-CoV-2 pandemic, and the safety of vaccines has become an important issue. COVID-19 vaccine-related central nervous system inflammatory demyelinating diseases (CNS IDDs) have been reported recently. We present one case of AstraZeneca vaccine-related myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease and a literature review of another 78 patients published from January 2020 to October 2022. Patients were divided into three vaccine types (viral vector, mRNA, and inactivated vaccines) for further analyses. Among 79 patients with COVID-19 vaccine-related CNS IDDs, 49 (62%) cases received viral vector vaccines, 20 (25.3%) received mRNA vaccines, and 10 (12.7%) received inactivated vaccines. Twenty-seven cases (34.2%) were confirmed with autoantibodies, including fifteen patients (19%) with anti-MOG, eleven (13.9%) with anti-aquaporin 4 (AQP4), and one (1.3%) with both antibodies. Significantly, more males developed CNS IDDs post viral vector vaccines compared to mRNA and inactivated vaccines. Patients receiving mRNA vaccines were older than those receiving other types. Furthermore, mRNA and inactivated vaccines correlated more with anti-AQP4 antibodies, while viral vector vaccines showed higher MOG positivity. This research suggests potential associations between COVID-19 vaccine-related CNS IDDs and gender, age, and autoantibodies, contingent on vaccine types. Protein sequence analysis implies similarities between the S protein and AQP4/MOG. Further studies may elucidate the mechanisms of CNS IDDs, aiding vaccine selection for specific types.

B cells orchestrate tolerance to the neuromyelitis optica autoantigen AQP4

Neuromyelitis optica is a paradigmatic autoimmune disease of the central nervous system, in which the water-channel protein AQP4 is the target antigen1. The immunopathology in neuromyelitis optica is largely driven by autoantibodies to AQP42. However, the T cell response that is required for the generation of these anti-AQP4 antibodies is not well understood. Here we show that B cells endogenously express AQP4 in response to activation with anti-CD40 and IL-21 and are able to present their endogenous AQP4 to T cells with an AQP4-specific T cell receptor (TCR). A population of thymic B cells emulates a CD40-stimulated B cell transcriptome, including AQP4 (in mice and humans), and efficiently purges the thymic TCR repertoire of AQP4-reactive clones. Genetic ablation of Aqp4 in B cells rescues AQP4-specific TCRs despite sufficient expression of AQP4 in medullary thymic epithelial cells, and B-cell-conditional AQP4-deficient mice are fully competent to raise AQP4-specific antibodies in productive germinal-centre responses. Thus, the negative selection of AQP4-specific thymocytes is dependent on the expression and presentation of AQP4 by thymic B cells. As AQP4 is expressed in B cells in a CD40-dependent (but not AIRE-dependent) manner, we propose that thymic B cells might tolerize against a group of germinal-centre-associated antigens, including disease-relevant autoantigens such as AQP4.

Infrequent patterns in cerebrospinal fluid isofocusing test: Clinical significance and contribution of IgG index and Reiber diagram to their interpretation

Cerebrospinal fluid (CSF) isoelectrofocusing (IEF) is considered as the gold standard for detecting an intrathecal synthesis of IgG, which is a hallmark of multiple sclerosis (MS). This corresponds to the presence of CSF-restricted IgG oligoclonal bands (OCB) (typically type 2 pattern). Moreover, this technique can also detect a systemic immune reaction with passive transfer of IgG (type 3 and 4 patterns) for which the clinical relevance is less understood. The aim of our study was to determine the frequency and disease associations of IEF type 3 and 4 patterns and to investigate the potential usefulness of including quantitative data (IgG index and Reiber Diagram) in interpreting such IEF profiles.Among 544 patients who underwent CSF IEF (Hydragel CSF isofocusing kit, Sebia®, France) in our Laboratory during a six-year-period, those who presented type 3 or 4 patterns were selected. Clinical data and results of other immunological tests were analyzed for 27 patients followed in the Neurological Department.Frequencies of type 3 and type 4 patterns were relatively low (2.3 % and 3.4 % respectively). Among patients with type 3 pattern included in our study (n = 10), 5 were diagnosed with MS. For the 5 other patients, the diagnosis was a clinically isolated syndrome (CIS) (2 cases), a probable auto-immune encephalitis (2 cases) and a possible genetic neurodegenerative disease (1 case). MS patients had an IgG index >0.7 and fell into area 4 of Reiber diagram while non-MS patients had an IgG index <0.7 and fell into area 1, except the last case. Regarding type 4 pattern (n = 17), the diagnoses were as follows: MS (3), CIS (4), Neuromyelitis optica spectrum disorders with positive anti-AQP4 antibodies (3) and anti-NMDAR autoimmune encephalitis (1). The remaining cases had central nervous system impairment related to vascular, metabolic or tumoral etiologies (3) or peripheral nervous system impairment (3). In this group (type 4 pattern), IgG index was <0.7 in 15/17 cases. Interpretation using Reiber diagram showed an abnormal blood-brain barrier for 8/17 patients.Type 3 and 4 IEF patterns are infrequently observed in routine neurology practice. It is important for the diagnostic laboratory professional as well as for the neurologist to understand their clinical relevance. Our findings highlight the contribution of quantitative evaluation of CSF (IgG index, Reiber diagram) for the interpretation of such situations. Despite the small size of our study population, our results emphasize the importance of reporting the exact type of IEF pattern and not only the positivity or not of OCB.

Peripheral memory B cells in multiple sclerosis vs. double negative B cells in neuromyelitis optica spectrum disorder: disease driving B cell subsets during CNS inflammation.

B cells are fundamental players in the pathophysiology of autoimmune diseases of the central nervous system, such as multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD). A deeper understanding of disease-specific B cell functions has led to the differentiation of both diseases and the development of different treatment strategies. While NMOSD is strongly associated with pathogenic anti-AQP4 IgG antibodies and proinflammatory cytokine pathways, no valid autoantibodies have been identified in MS yet, apart from certain antigen targets that require further evaluation. Although both diseases can be effectively treated with B cell depleting therapies, there are distinct differences in the peripheral B cell subsets that influence CNS inflammation. An increased peripheral blood double negative B cells (DN B cells) and plasmablast populations has been demonstrated in NMOSD, but not consistently in MS patients. Furthermore, DN B cells are also elevated in rheumatic diseases and other autoimmune entities such as myasthenia gravis and Guillain-Barré syndrome, providing indirect evidence for a possible involvement of DN B cells in other autoantibody-mediated diseases. In MS, the peripheral memory B cell pool is affected by many treatments, providing indirect evidence for the involvement of memory B cells in MS pathophysiology. Moreover, it must be considered that an important effector function of B cells in MS may be the presentation of antigens to peripheral immune cells, including T cells, since B cells have been shown to be able to recirculate in the periphery after encountering CNS antigens. In conclusion, there are clear differences in the composition of B cell populations in MS and NMOSD and treatment strategies differ, with the exception of broad B cell depletion. This review provides a detailed overview of the role of different B cell subsets in MS and NMOSD and their implications for treatment options. Specifically targeting DN B cells and plasmablasts in NMOSD as opposed to memory B cells in MS may result in more precise B cell therapies for both diseases.

Cancer-associated neuromyelitis optica spectrum disorder: a case report with literature review.

Neuromyelitis optica spectrum disorders (NMOSD) is one of autoimmune inflammatory diseases and is characterized by area postrema syndrome, brainstem syndrome, optic neuritis, and/or myelitis. Typical myelitis is longitudinally extended transverse myelitis (LETM) which extends over three vertebral bodies. Several previous case reports have suggested association between cancer and NMOSD. A 50-year-old woman had breast cancer and underwent mastectomy and, 10 months later, she had developed acutely progressive dysbasia. Spine MRI showed LETM in 13 vertebrae length and blood test revealed positive anti-aquaporin 4 (anti-AQP4) antibody based on enzyme-linked immunosorbent assay with index of over 40. She was treated by intravenous methylprednisolone, plasma exchange, and intravenous immunoglobulin, followed by oral prednisolone. The condition had mostly recovered after the treatment. A small population of NMOSD has the aspect of paraneoplastic neurological syndrome. The age of onset in patients with cancer-associated NMOSD tends to be higher than that in individuals with NMOSD due to any causes of NMOSD.

Chapter 12 - Hematopoietic stem cell transplantation for neuromyelitis optica spectrum disorder. Can immune tolerance be reestablished?

Neuromyelitis optica (NMO), which is also referred to as Devic's disease, was originally considered an aggressive subtype of multiple sclerosis (MS) presenting as optic neuritis and/or extensive transverse myelitis in which 50% of patients become blind or in a wheelchair within 5 years of onset. Subsequently, NMO was categorized as one of a spectrum of inflammatory and demyelinating autoimmune disorders that are distinct from multiple sclerosis and termed neuromyelitis optica spectrum disorder (NMOSD). NMOSD differs from multiple sclerosis by its clinical course, presentation, magnetic resonance imaging findings, clinical presentation, serum biomarker prognosis, and response to treatment. More recently, NMOSD has been subdivided according to auto-antibody status as aquaporin 4 (AQP4) seropositive NMO, myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD), and seronegative NMOSD. The only treatment to date that has resulted in treatment-free remissions, now lasting for more than 5-10 years with posttreatment disappearance of anti-AQP4 antibodies, is hematopoietic stem cell transplantation (HSCT) using either an allogeneic (matched sibling or unrelated) donor with a reduced toxicity conditioning regimen or an autologous stem cell source using a nonmyeloablative conditioning regimen of plasmapheresis (PLEX), cyclophosphamide (Cytoxan®), rabbit antithymocyte (ATG), and rituximab (Rituxan®). Post-HSCT long-term resolution of disease activity and disappearance of AQP4 antibodies is consistent with HSCT-induced immune tolerance.

B-101 Aquaporin 4 and Neuromyelitis Optica Spectrum Disorders

Abstract Background Neuromyelitis óptica (NMO) is a rare demyelinating inflammatory disease of the central nervous system, characterized by acute optic neuritis (ON) and transverse myelitis (TM). Previously, it was considered as a variant of multiple sclerosis (MS), however, there are now several clinical, laboratory, neuroimaging and pathological anatomical features that distinguish it from MS as the presence of a specific autoantibody in blood called IgG-NMO or anti-AQP4 that binds to water channels named aquaporin-4 (AQP4) expressed on astrocytes and plays a key role in the pathogenesis of this disease. Some patients remain seronegative for AQP4-IgG despite a definite diagnosis of NMO and the use of the finest methods for antibody detection. In anti-AQP4 seronegative forms, antibodies against myelin oligodendrocyte glycoprotein (MOG) may be identified. We have carried out a review of those patients with anti-AQP4-IgG detected in the autoimmunity laboratory during the last 3 years. Methods Each year we receive an average of 260 samples from patients with suspected demyelinating pathology with or without visual impairment. For the detection of antibodies against AQP-4 specifically HEK293 cells transfected were used as the standard substrate. Anti-MOG antibody can be detected in the same test. Measurement range: The dilution starting point for this measurement system is 1:10 (serum/plasma) and 1:1 (CSF, undiluted). Results A total of 5 patients were positive for anti AQP-4 antibody in serum samples, all women aged between 23 and 78 years. All patients except the youngest, who presented to the neurology department for loss of visual acuity, had other autoimmune diseases: systemic lupus erythematosus (SLE) in conjunction with rheumatoid arthritis, SLE in conjunction with Graves’ disease and hypothyroidism, the two oldest (59 and 78 years), respectively. The oldest patient was admitted to the internal medicine department for persistent nausea, vomiting and hiccups and was diagnosed as NMO spectrum disorder. In all cases, the oligoclonal immunoglobulin G bands study in CSF was negative. None of the CSF samples tested were positive for anti AQP-4 antibody. All patients were treated with methylprednisolone, but treatment with azathioprine or rituximab was necessary in 3 patients. Conclusion Titers of antibodies against AQP-4 are significantly higher in serum than in CSF, with serum being the most sensitive simple. NMO is more prevalent in women than men, with a female predominance usually higher than observed in MS. The median age of onset is also higher than MS, with a median of 35–45 years. Since the discovery of AQ-4 antibodies, there has been an increase in the number of clinical and radiological manifestations of NMO beyond involvement of the optic nerve and the spinal cord, including manifestations in the brain. It is important to recognise them in order to make an early diagnosis, to avoid unnecessary complementary tests and to establish the most suitable treatment. Persistent and intractable hiccups and nausea may occur in 17%–43% as in our oldest patient’s case. Associations with organ-specific autoimmune diseases such as autoimmune thyroiditis, and non-organ-specific diseases such as SLE and Sjögren’s syndrome have been described.

West syndrome and multiple sclerosis association

Introduction. West syndrome is a rare and severe infantile epileptic encephalopathy, beginning around the age of six months, characterized by a classic electro-clinical triad. This is a pathology totally different from multiple sclerosis (MS) which is a demyelinating disease of the central nervous system caused, affecting young adults, especially females. The association of these two pathologies has never been described. Observation. We report here an exceptional presentation of MS in a 14-year-old girl with a history of West syndrome. She had normal development until the age of six months, when she began to have flexion spasms. The diagnosis of West syndrome was made with a normal MRI. The infantile spasms disappeared after treatment with vigabatrin and adrenocorticotropic hormone (ACTH). It had generally progressed to Lennox Gastaut encephalopathy, with delayed psychomotor development and epileptic sequelae. At 14, she presented with left hemiparesis within a few days. A cerebral MRI showed multiple nodular hyperintensities of the supra and infratentorial white matter, with the presence of an active lesion, fulfilling the diagnostic criteria for multiple sclerosis. CSF analysis was normal. Anti-AQP4, anti-MOG, anti-NMDA and anti-GABA (AB) antibodies were absent in the blood. Antibodies against HIV and viral hepatitis were. Biotinidase activity and autoimmunity tests were correct. The patient received high doses of methylprednisolone IV (1g/day) for three days with remarkable clinical improvement after 15 days. Discussion. MS is a complex and heterogeneous central nervous system (CNS) demyelinating disease. It is not uncommon for epilepsy to be the first symptom of multiple sclerosis. Seizures, on the other hand, are more common after disease progression. Although the disease is characterized by inflammatory lesions of the white matter, various neuropathological and radiological studies have shown that the disease also affects the grey matter. Several studies have shown that seizures are three to six times more common in MS patients than in the general population. Even though MS can start with epilepsy and a seizure may be the only symptom of a relapse of MS, it is still not known whether the two diseases coexist or whether MS predisposes to seizures. Conclusion. The association of these two totally different pathologies can lead us to say that the mechanism of multiple sclerosis may begin in childhood and that the clinical signs appear in adulthood.

Contactin-associated protein-2 and anti-aquaporin-4 antibody positive autoimmune encephalitis secondary to herpes simplex encephalitis: A case report.

Recurrent herpes simplex encephalitis (HSE) can easily induce autoimmune encephalitis (AE). However, there are few reports of anti-contactin-associated protein-2 (CASPR2)-related encephalitis, especially with positive anti-aquaporin 4 (AQP4) antibodies. A 14-year-old boy was admitted to the Department of Neurology of the First Affiliated Hospital of Kunming Medical University for "headache, dizziness, and fever for four days" with positive anti-CASPR2 and anti-AQP4 antibodies in the cerebrospinal fluid. Cranial MRI showed lesions in the right hippocampus, amygdala, and insular lobe, with local sulcus enhancement in the right insular, temporal, and frontal lobes. The fluid-attenuated inversion recovery was significantly enhanced. Human herpes virus type I was detected by cerebrospinal fluid metagenomic testing. The patient was diagnosed with AE secondary to HSE, with positive anti-CASPR2 and anti-AQP4 antibodies. After 2 weeks of immunoglobulin and methylprednisolone immunomodulatory therapy, acyclovir antivirus, mannitol dehydration, reducing intracranial pressure, and other symptomatic support therapy. The patient's symptoms significantly improved, with no complaints of discomfort, and he was discharged for observation. The patient was followed up a month after discharge and had no complaints of discomfort. CASPR2 and anti-aquaporin-4 antibody-positive AE have not been reported to be positive. This case will raise awareness of CASPR2 and anti-aquaporin-4 antibody-positive AE secondary to HSE, strengthen diagnostic capacities, and provide advice to treat it.

Establishment of a comprehensive diagnostic model for neuromyelitis optica spectrum disorders based on the analysis of laboratory indicators and clinical data.

To establish a comprehensive diagnostic model for neuromyelitis optica spectrum disorders (NMOSDs) based on laboratory indicators and clinical data. A retrospective method was used to query the medical records of patients with NMOSD from January 2019 to December 2021. At the same time, clinical data of other neurological diseases were also collected for comparison. Clinical data of the NMOSD group and non-NMOSD group were analyzed, and the diagnostic model was established based on these data. In addition, the model was evaluated and verified by the receiver operating curve. A total of 73 patients with NMOSD were included, and the ratio of males to females was 1:3.06. The indicators that showed differences between the NMOSD group and non NMOSD group included neutrophils (P = 0.0438), PT (P = 0.0028), APTT (P < 0.0001), CK (P = 0.002), IBIL (P = 0.0181), DBIL (P < 0.0001), TG (P = 0.0078), TC (P = 0.0117), LDL-C (P = 0.0054), ApoA1 (P = 0.0123), ApoB (P = 0.0217), TPO antibody (P = 0.012), T3 (P = 0.0446), B lymphocyte subsets (P = 0.0437), urine sg (P = 0.0123), urine pH (P = 0.0462), anti-SS-A antibody (P = 0.0036), RO-52 (P = 0.0138), CSF simplex virus antibody I-IGG (P = 0.0103), anti-AQP4 antibody (P < 0.0001), and anti-MOG antibody (P = 0.0036). Logistic regression analysis showed that changes in ocular symptoms, anti-SSA antibody, anti-TPO antibody, B lymphocyte subsets, anti-AQP4 antibody, anti-MOG antibody, TG, LDL, ApoB, and APTT had a significant impact on diagnosis. The AUC of the combined analysis was 0.959. The AUC of the new ROC for AQP4- and MOG- antibody negative NMOSD was 0.862. A diagnostic model was successfully established, which can play an important role in differential diagnosis of NMOSD.

Cryoglobulinemia and Neuromyelitis optica: a case of progressive weakness and neurocognitive decline (P10-5.026)

<h3>Objective:</h3> Describe a case of a woman with mixed cryoglobulinemia who presented with progressive weakness and biopsy proven systemic vasculitis in the setting of Hepatitis C virus (HCV) negative serology. <h3>Background:</h3> The disease expression of mixed cryoglobulinemia vasculitis caused by HCV infection triggers the downstream B-cell arm of autoimmunity. <h3>Design/Methods:</h3> A 61 year old woman with a history of HCV infection, mixed cryoglobulinemia, mononeuritis multiplex secondary to nervous system vasculitis affecting peripheral nerves and hypertension presented with weakness that progressed to quadriparesis and neurocognitive decline over a period of eight months. <h3>Results:</h3> MRI examination of the brain showed bilateral ventral pontine lesions extending into the middle cerebellar peduncles, ventrolateral midbrain and cerebral peduncles as well as bilateral cortical frontal lobe lesions. Also present were intrinsic mixed intensity DWI/ADC lesions of undetermined etiology and extensive subcortical and periventricular white matter hyperintensities. CT angiography of her head and neck showed large vessel intracranial vasculopathy involving the bilateral MCA branches. Conventional angiogram, however, did not show any evidence of angiographic vasculitis. MRI spectroscopy was non-diagnostic. MRI of the neuroaxis showed a small focus of linear non-enhancing hyperintense lesion at the level of C3. EMG demonstrated severe generalized sensory-motor polyneuropathy with severe axonal loss. EEG showed mild to moderate diffuse slowing. CSF evaluation was negative, HCV viral load was undetectable, connective tissue markers (Anti-dsDNA, Anti-SCL70, Anti-CENTR, Anti-RNP, Anti-Smith, Anti-SSA/SSB, ANCA) were negative and the remaining serology was significant for elevated ESR, CRP, low C4 complements, positive anti-AQP4 antibodies titers (1:2560) and positive myelin basic protein. Brain biopsy showed perivascular lymphocytic inflammation, confirming vasculitis. Our patient completed courses of high dose steroids, IVIG and Rituximab with mild improvement in motor strength. <h3>Conclusions:</h3> Although an atypical feature of NMO, cryoglobulinemia with production of anti-AQP4 antibodies may, in part, contribute to development of a demyelinating process. <b>Disclosure:</b> Dr. Esechie has nothing to disclose. Dr. Harazeen has nothing to disclose. Dr. Rivera Vega has nothing to disclose. Dr. Thottempudi has nothing to disclose. Dr. Chhabra has stock in Pfizer. Dr. Chhabra has stock in Biogen. Dr. Chhabra has stock in Johnson and Johnson. Dr. Chhabra has stock in Medtronic. Dr. Shaltoni has nothing to disclose. Muhammad Zeeshan Memon, MD has nothing to disclose. Dr. Patel has nothing to disclose. Dr. Wu has nothing to disclose.

Diseases associated antibodies anti-MOG and double seronegative NMOsd during the COVID-19 pandemic. Interim analysis of a cohort study. (P13-5.012)

<h3>Objective:</h3> To describe the clinical and demographic findings of patients from the National Institute of Neurology and Neurosurgery anti-MOG validation cohort tested for anti-MOG and anti-AQP4. <h3>Background:</h3> Anti-MOG associated diseases (MOGAD) include demyelinating disease phenotypes such as optic neuritis, longitudinally extensive transverse myelitis, acute disseminated encephalomyelitis, Neuromyelitis Optica syndrome (NMOsd) among others. In our country, the incidence of this pathology is unknown, mainly due to the lack of diagnostic tools. <h3>Design/Methods:</h3> As part of the cohort of the National Institute of Neurology and Neurosurgery in Mexico, for the validation of a MOG CBA-assay, anti-AQP4 and MOG antibody tests were requested from those patients who met the Jarius 2018 criteria for MOGAD. Measurements of central tendency are made for each group and we analyze the MOG+ and double seronegative groups with Fisher’s exact and Mann Whitney. <h3>Results:</h3> Eighteen patients were analyzed. Seven patients were MOG+, 62% women. The mean age for patients with MOG was 40 years. Presentation was 100% atypical optic neuritis. The anterior segment was more affected in 42% of the patients. Five (71.4%) patients had a deficit &gt;200/100, 3 of them improved to 20/40 regardless of whether or not they received plasmapheresis (X2 0.833 p=0.361). Post-vaccination possibility was documented in 57%. There were no significant differences between patients with different sero-status. Four patients are maintained with Rituximab support treatment. <h3>Conclusions:</h3> MOG+ patients were mostly women, despite a severe initial deficit, an adequate visual recovery was documented regardless of the plasmapheresis time. A larger number of patients are required to perform a pairwise comparison with those with AQP4+. <b>Disclosure:</b> Dr. Rodriguez has nothing to disclose. Dr. Aguilar-Gonzalez has nothing to disclose. Veronica Rivas has nothing to disclose. Dr. Flores-Rivera has nothing to disclose. Teresita Corona Vazquez has nothing to disclose.

Neuromyelitis Optica Spectrum Disorder (NMOSD) Relapse Triggered by Secondary Syphilis: A Case Report (P10-5.021)

<h3>Objective:</h3> Not applicable <h3>Background:</h3> This report represents a case of post-infections NMOSD relapse due to syphilis. <h3>Design/Methods:</h3> Not applicable <h3>Results:</h3> A 25-year-old woman was admitted in the emergency room with an acute onset of paresthesia in the upper and lower limbs and an electric shock sensation irradiating to both arms during neck flexion (Lhermitte’s sign). She had round hyperchromic papular lesions in the palms and soles, which were painless, non-pruritic and appeared at the same time as the neurological picture. In the neurological examination, she presented sensory ataxic gait, positive Romberg maneuver, dysmetria in the finger-nose test with eyes closed, slight proximal and distal weakness in the left arm, hyperreflexia in all four limbs with bilateral Achilles clonus, apalesthesia with loss of proprioception in the hands, painful anesthesia in the right arm and painful hypoesthesia in the right foot and left leg. She had a previous history of systemic lupus erythematosus since the age of 14, and NMOSD with positive serum anti-AQP4 antibody diagnosed at the age of 23. In the current relapse, serum VDRL was 1:32, CSF was normal, and MRI showed an extensive area of increased signal in cervical cord suggesting longitudinally extensive myelitis. The diagnosis of an acute attack of NMOSD triggered by secondary syphilis (roseola syphilitic) was established. She received one dose of 2.4 million I.U. benzathine penicillin, and methylprednisolone treatment was initiated, with no positive results. Plasmapheresis was then performed, with improvement of the strength, sensibility, and coordination. <h3>Conclusions:</h3> The post-infectious acute attacks of NMOSD are represented in literature through few cases reported. The present case highlights the importance of seeking the specific etiology of an NMOSD relapse, allowing not only its treatment but also the identification and elimination of a possible underlying infectious agent. <b>Disclosure:</b> Dr. Lima has nothing to disclose. Dr. Schafascheck has nothing to disclose. Dr. Moura has nothing to disclose. Dr. Carvalho has nothing to disclose. Dr. Seide Cardoso has nothing to disclose. Dr. Colares Lessa has nothing to disclose. Miss Mageste has nothing to disclose. Dr. Gaudio has nothing to disclose. Dr. Braune has nothing to disclose.