Application of the 2015 diagnostic criteria for neuromyelitis optica spectrum disorders in a cohort of Latin American patients

Application and interpretation of core elements of the 2015 NMOSD diagnostic criteria in routine clinical practice

Background

We evaluated comprehension and application of the 2015 neuromyelitis optica spectrum disorder (NMOSD) criteria core elements by neurologists in Latin America (LATAM) who routinely diagnose and care for NMOSD patients by (i) identifying typical/suggestive NMOSD syndromes, (ii) detecting typical MRI NMOSD lesions and meeting MRI dissemination in space (DIS) criteria, and (iii) evaluating historical symptoms suggestive of NMOSD.

Methods

We conducted an anonymous, voluntary, self-administered web- and case-based survey cross-sectional study from October 2023 to January 2024 of neurologists identified through the LACTRIMS database. Questions were presented first through iterative clinical cases or imaging, followed by questions directly evaluating comprehension of definitions. "Correct" responses were based on the 2015 criteria and adjudicated by the consensus of the experts leading the project.

Results

A total of 106 neurologists (60.3% female; mean age: 46.6 ± 12.5 years) were included. Between 10.4% and 49.1% of neurologists inaccurately identified clinical or paraclinical aspects for DIS and 32.1% accurately identified the three non-cardinal (brainstem, diencephalic, and cerebral) syndromes for seronegative patients. Between 35.8% and 64.1% of neurologists identified the "optimal timing" of AQP4-IgG testing (e.g., during an attack or before receiving immunosuppressant treatments, among others); 56.6% considered live cell-based assay as the gold standard method for serological testing. Most neurologists accurately identified typical NMOSD MRI lesions, but periventricular, juxtacortical/cortical, fluffy infratentorial, corticospinal tract, and hypothalamic lesions were frequently misidentified.

Conclusion

Clinical scenarios were identified where the 2015 NMOSD criteria were susceptible to misinterpretation and misapplication by expert neurologists in LATAM. Implementing collaborative educational initiatives could improve NMOSD diagnosis and raise patient care standards.

[The diagnostic effectiveness of criteria for neuromyelitis optica spectrum disorders in the Russian clinical practice]

OBJECTIVE

To compare the diagnostic criteria of 2006 (DC 2006) and 2015 (DC 2015) in the Russian population of patients with suspected neuromyelitis optica spectrum disorders (NMOSD), with the calculation of their sensitivity, specificity, accuracy and predictive value.

MATERIAL AND METHODS

We reviewed medical records of suspected NMOSD patients who were therefore examined for the presence of serum autoantibodies targeting the aquaporin-4 water channel protein (AQP4-IgG) in 6 specialized Russian (Nizhny Novgorod and Moscow) medical centers. One hundred patients (78 female), aged 17 to 74 years (mean 38.1±13.3 years), were included. The follow-up period ranged from 4 to 108 months (mean 59.7±31.6 months).

RESULTS

During the follow-up the diagnosis of NMOSD was confirmed in 32 people, and 68 patients had diagnoses different from NMOSD. At the disease onset, 68.8% of patients were seropositive for AQP4-IgG. The mean time for confirming NMOSD diagnosis was 15.2±14.2 months. At the disease onset, 36% of patients fulfilled the DC 2015, the diagnosis was subsequently confirmed in 77.8% out of them. 26% of the patients fulfilled the DC 2006, the diagnosis was subsequently confirmed in 84.6% out of them. The sensitivity of DC 2006/DC 2015 was 69%/88%, specificity 94%/88%, accuracy 86%/88%, negative predictive value 85%/94%, positive predictive value 86%/78%.

CONCLUSION

The specificity, sensitivity and accuracy of modern diagnostic criteria for NMOSD In Russian patients is comparable to those obtained in foreign studies. DC 2015 helps to diagnose NMOSD earlier than DC 2006, but they have a lower specificity.

A comprehensive review of the advances in neuromyelitis optica spectrum disorder

Neuromyelitis optica spectrum disorder (NMOSD) is a rare relapsing neuroinflammatory autoimmune astrocytopathy, with a predilection for the optic nerves and spinal cord. Most cases are characterised by aquaporin-4-antibody positivity and have a relapsing disease course, which is associated with accrual of disability. Although the prognosis in NMOSD has improved markedly over the past few years owing to advances in diagnosis and therapeutics, it remains a severe disease. In this article, we review the evolution of our understanding of NMOSD, its pathogenesis, clinical features, disease course, treatment options and associated symptoms. We also address the gaps in knowledge and areas for future research focus.

Barriers to access and unmet needs to neuromyelitis optica spectrum disorders care in an Argentinean cohort

INTRODUCTION

Neuromyelitis optica spectrum disorder (NMOSD) is a rare but severe neuroimmunological condition associated with a significant financial burden. NMOSD is also associated with increased health care utilization, including neurology outpatient visits, magnetic resonance imaging (MRI) use, long-term medication, among others. We aimed to evaluate real-world patient experiences in access to care and NMOSD burden in an Argentinean cohort.

METHODS

This cross-sectional study used a self-administered survey and was conducted in Argentina (2022). Patients with NMOSD were divided into three groups: private health insurance (PHI), social health insurance (SHI), and public health insurance (PHI, Ministry of Public Health). Differences in access and health care barriers were assessed.

RESULTS

One hundred patients with NMOSD (74 women) with a mean age at diagnosis of 38.7 years were included. Their EDSS was 2.8 and they were followed for 5.2 years. Of them, 51%, 11%, and 13% were employed (full-time: 57.5%), currently unemployed and retired by NMOSD, respectively. 55% of them visited between 2-3 specialists before NMOSD diagnosis. Aquaporin-4-antibody and/or myelin oligodendrocyte glycoprotein-antibody testing was requested in 91% (health insurance covered this partially in 15.3% and 32.9% of the time the test was entirely paid by patient/family). Patients with NMOSD receiving private medical care reported greater access to MRI, outpatient visits, and fewer issues to obtain NMOSD medications compared to those treated at public institutions. A longer mean time to MRI and neurology visit was found in the PHI group when compared with the other two subgroups. Regression analysis showed that private insurance (OR=3.84, p=0.01) was the only independent factor associated with appropriate access to NMOSD medications in Argentina.

CONCLUSION

These findings suggest that barriers to access and utilization of NMOSD care services in Argentina are common. NMOSD patients experienced problems to receive NMOSD medication properly, especially those from the public sector.

Frequency of NMOSD misdiagnosis in a cohort from Latin America: Impact and evaluation of different contributors

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) misdiagnosis (i.e. the incorrect diagnosis of patients who truly have NMOSD) remains an issue in clinical practice. We determined the frequency and factors associated with NMOSD misdiagnosis in patients evaluated in a cohort from Latin America.

METHODS

We retrospectively reviewed the medical records of patients with NMOSD, according to the 2015 diagnostic criteria, from referral clinics in six Latin American countries (Argentina, Chile, Paraguay, Colombia, Ecuador, and Venezuela). Diagnoses prior to NMOSD and ultimate diagnoses, demographic, clinical and paraclinical data, and treatment schemes were evaluated.

RESULTS

A total of 469 patients presented with an established diagnosis of NMOSD (73.2% seropositive) and after evaluation, we determined that 56 (12%) patients had been initially misdiagnosed with a disease other than NMOSD. The most frequent alternative diagnoses were multiple sclerosis (MS; 66.1%), clinically isolated syndrome (17.9%), and cerebrovascular disease (3.6%). NMOSD misdiagnosis was determined by MS/NMOSD specialists in 33.9% of cases. An atypical MS syndrome was found in 86% of misdiagnosed patients, 50% had NMOSD red flags in brain and/or spinal magnetic resonance imaging (MRI), and 71.5% were prescribed disease-modifying drugs.

CONCLUSIONS

NMOSD misdiagnosis is relatively frequent in Latin America (12%). Misapplication and misinterpretation of clinical and neuroradiological findings are relevant factors associated with misdiagnosis.

Neuromyelitis Optica Spectrum Disorder in Central America and the Caribbean: A Multinational Clinical Characterization Study

Here, a study of NMOSD in Central America and the Caribbean with a multinational collaborative, multicentric and descriptive approach involving 25 institutions from 9 countries is presented. Demographics, clinical manifestations, expanded disability scale status (EDSS), brain and spinal cord MRI, serological anti-AQP4-IgG and anti-MOG-IgG antibodies, and cerebrospinal fluid (CSF) oligoclonal bands were included. A central serological repository utilized the cell-based assay. The specimens outside of this network employed diverse methodologies. Data were collected at the Gorgas Commemorative Institute of Health Studies (ICGES), Panama, and included 186 subjects, of which 84% were females (sex ratio of 5.6:1). Mestizos constituted 72% of the study group. The median age was 42.5 years (IQR: 32.0–52.0). Associated autoimmune diseases (8.1%) were myasthenia gravis, Sjögren’s syndrome and systemic lupus erythematosus. The most common manifestation was optic neuritis-transverse myelitis (42.5%). A relapsing course was described in 72.3% of cases. EDSS scores of 0–3.5 were reported in 57.2% of cases and higher than 7.0 in 14.5%. Positive anti-AQP4-IgG antibody occurred in 59.8% and anti-MOG-IgG antibody in 11.5% of individuals. Antibody testing was lacking for 13.4% of patients. The estimated crude prevalence of NMOSD from Panama and the Dominican Republic was 1.62/100,000 (incidence of 0.08–0.41) and 0.73/100,000 (incidence 0.02–0.14), respectively. This multinational study contributes additional insights and data on the understanding of NMOSD in this Latin American region.

Seasonal variation in attacks of neuromyelitis optica spectrum disorders and multiple sclerosis: Evaluation of 794 attacks from a nationwide registry in Argentina

BACKGROUND

Identification of triggers that potentially instigate attacks in neuromyelitis optica spectrum disorders (NMOSD) and multiple sclerosis (MS) has remained challenging. We aimed to analyze the seasonality of NMOSD and MS attacks in an Argentinean cohort seeking differences between the two disorders.

METHODS

A retrospective study was conducted in a cohort of NMOSD and MS patients followed in specialized centers from Argentina and enrolled in RelevarEM, a nationwide, longitudinal, observational, non-mandatory registry of MS/NMOSD patients. Patients with complete relapse data (date, month and year) at onset and during follow-up were included. Attack counts were analyzed by month using a Poisson regression model with the median monthly attack count used as reference.

RESULTS

A total of 551 patients (431 MS and 120 NMOSD), experiencing 236 NMOSD-related attacks and 558 MS-related attacks were enrolled. The mean age at disease onset in NMOSD was 39.5 ± 5.8 vs. 31.2 ± 9.6 years in MS (p < 0.01). Mean follow-up time was 6.1 ± 3.0 vs. 7.4 ± 2.4 years (p < 0.01), respectively. Most of the included patients were female in both groups (79% vs. 60%, p < 0.01). We found a peak of number of attacks in June (NMOSD: 28 attacks (11.8%) vs MS: 33 attacks (5.9%), incidence rate ratio 1.82, 95%CI 1.15-2.12, p = 0.03), but no differences were found across the months in both disorders when evaluated separately. Strikingly, we observed a significant difference in the incidence rate ratio of attacks during the winter season when comparing NMOSD vs. MS (NMOSD: 75 attacks (31.7%) vs MS: 96 attacks (17.2%), incidence rate ratio 1.82, 95%CI 1.21-2.01, p = 0.02) after applying Poisson regression model. Similar results were observed when comparing the seropositive NMOSD (n = 75) subgroup vs. MS.

CONCLUSIONS

Lack of seasonal variation in MS and NMOSD attacks was observed when evaluated separately. Future epidemiological studies about the effect of different environmental factors on MS and NMOSD attacks should be evaluated prospectively in Latin America population.

Randomized Controlled Trials for Neuromyelitis Optica Spectrum Disorder: A Review of Trial Architecture

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is a relapsing inflammatory disease that primarily affects the optic nerves and the spinal cord. Randomized controlled trials (RCTs) assessing treatments for NMOSD have only been performed in the past decade, and to date, there are 3 drugs approved by the US Food and Drug Administration (FDA) for antiaquaporin-4 immunoglobulin G seropositive NMOSD. This review assesses the characteristics and challenges of RCTs when evaluating treatments for NMOSD.

REVIEW SUMMARY

We conducted a review using the terms ("neuromyelitis optica" OR "NMO" OR "NMOSD") AND "clinical trial" in any language on March 28, 2021. Seven RCTs were included, and the trials' architecture was analyzed and synthesized. Overall, 794 subjects were randomized [monoclonal antibody intervention group, n= 493 (62.1%), placebo, n=196 (24.7%), and active control, n=105 (13.2%)]; 709 (89.3%) were females; and 658 (82.9%) were aquaporin-4 (AQP4) antibody seropositive. The primary outcome was time to relapse in 6/7 of the trials, and annualized relapse rate in the remaining one. Four RCTs used placebo in their design. Among the seven published RCTs, the trial design differed by the criteria used to define NMOSD relapse, selection of subjects, proportion of AQP4 immunoglobulin G seronegative patients, and baseline characteristics indicating NMO disease severity.

CONCLUSIONS

Ethical considerations for the use of placebo should change in light of the approval of 3 therapies for seropositive NMOSD. Remaining challenges for clinical trials in NMOSD include the assessment of long-term safety and efficacy, standardization of trial design and endpoints, and head-to-head study designs.

Comparisons of clinical phenotype, radiological and laboratory features, and therapy of neuromyelitis optica spectrum disorder by regions: update and challenges

Neuromyelitis optica spectrum disorder (NMOSD) is an inflammatory demyelinating disease of the central nervous system (CNS) associated with autoantibody (ab) to aquaporin-4 (AQP4). There is obvious variation between regions and countries in the epidemiology, clinical features and management in NMOSD. Based on published population-based observation and cohort studies, the different clinical pattern of NMOSD has been seen in several geographical regions and some of these patients with NMOSD-like features do not fully meet the current diagnostic criteria, which is needed to consider the value of recently revised diagnostic criteria. At present, all treatments applied in NMOSD have made great progress, however, these treatments failed in AQP4 ab negative and refractory patients. Therefore, it is necessary to turn into an innovative idea and to open a new era of NMOSD treatment to develop novel and diverse targets and effective therapeutic drugs in NMOSD and to conduct the trails in large clinical samples and case-control studies to confirm their therapeutic effects on NMOSD in the future, which still remain a challenge.

The costs of care from a US claims database in patients with neuromyelitis optica spectrum disorder

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune disease of the central nervous system that often leads to severe disability. Patients with highly active NMOSD have approximately a 10-times higher hospital inpatient admission rate compared with patients without NMOSD. Accurate assessments of the impact of NMOSD treatments on the burdens of illness require quantitative metrics of these burdens, including costs of care.

METHODS

This study evaluated claims data from the IBM MarketScan Commercial and Medicare Supplemental Databases between 2014 and 2018. Patients were included based on inpatient or outpatient claims meeting criteria defined for NMOSD. Non-NMOSD controls were matched 5:1 to patients with NMOSD. Total costs of healthcare services in consumer price index-adjusted 2019 US dollars during the 1-year postindex follow-up period were calculated for patients and controls.

RESULTS

Patients with NMOSD required more healthcare services and incurred significantly greater costs for inpatient hospitalizations (annual mean [SD] cost: $29,054 [$144,872] vs controls $1521 [$10,759]), outpatient services ($24,881 [$35,463] vs $4761 [$26,447]), and emergency department (ED) visits ($2400 [$7771] vs $408 [$2579]). Almost 12% of patients with NMOSD were further burdened with plasma exchange or intravenous immunoglobulin G treatments, costing an annual median (interquartile range) of $1684 ($566-$3817) and $24,353 ($5425-$42,975), respectively.

CONCLUSIONS

Compared with controls, patients with NMOSD had significantly higher costs associated with hospitalizations, ED visits, and prescriptions. These results highlight the considerable economic burden of NMOSD, which may be favorably impacted by disease-modifying therapies that are regulatory-approved to be safe and effective.

Status of the neuromyelitis optica spectrum disorder in Latin America

BACKGROUND

Neuromyelitis optica spectrum disorders (NMOSD) is an increasing diagnostic and therapeutic challenge in Latin America (LATAM). Despite the heterogeneity of this population, ethnic and socioeconomic commonalities exist, and epidemiologic studies from the region have had a limited geographic and population outreach. Identification of some aspects from the entire region are lacking.

OBJECTIVES

To determine ethnic, clinical characteristics, and utilization of diagnostic tools and types of therapy for patients with NMOSD in the entire Latin American region.

METHODS

The Latin American Committee for Treatment and Research in MS (LACTRIMS) created an exploratory investigational survey addressed by Invitation to NMOSD Latin American experts identified through diverse sources. Data input closed after 30 days from the initial invitation. The questionnaire allowed use of absolute numbers or percentages. Multiple option responses covering 25 themes included definition of type of practice; number of NMOSD cases; ethnicity; utilization of the 2015 International Panel criteria for the diagnosis of Neuromyelitis optica (IPDN); clinical phenotypes; methodology utilized for determination of anti-Aquaporin-4 (anti- AQP4) antibodies serological testing, and if this was performed locally or processed abroad; treatment of relapses, and long-term management were surveyed.

RESULTS

We identified 62 investigators from 21 countries reporting information from 2154 patients (utilizing the IPDN criteria in 93.9% of cases), which were categorized in two geographical regions: North-Central, including the Caribbean (NCC), and South America (SA). Ethnic identification disclosed Mestizos 61.4% as the main group. The most common presenting symptoms were concomitant presence of optic neuritis and transverse myelitis in 31.8% (p=0.95); only optic neuritis in 31.4% (more common in SA), p<0.001); involvement of the area postrema occurred in 21.5% and brain stem in 8.3%, both were more frequent in the South American cases (p<0.001). Anti-AQP4 antibodies were positive in 63.9% and anti-Myelin Oligodendrocyte Glycoprotein (MOG) antibodies in 4.8% of total cases. The specific laboratorial method employed was not known by 23.8% of the investigators. Acute relapses were identified in 81.6% of cases, and were treated in 93.9% of them with intravenous steroids (IVS); 62.1% with plasma exchange (PE), and 40.9% with intravenous immunoglobulin-G (IVIG). Therapy was escalated in some cases due to suboptimal initial response. Respondents favored Rituximab as long-term therapy (86.3%), whereas azathioprine was also utilized on 81.8% of the cases, either agent used indistinctly by the investigators according to treatment accessibility or clinical judgement. There were no differences among the geographic regions.

CONCLUSIONS

This is the first study including all countries of LATAM and the largest cohort reported from a multinational specific world area. Ethnic distributions and phenotypic features of the disease in the region, challenges in access to diagnostic tools and therapy were identified. The Latin American neurological community should play a determinant role encouraging and advising local institutions and health officials in the availability of more sensitive and modern diagnostic methodology, in facilitating the the access to licensed medications for NMOSD, and addressing concerns on education, diagnosis and management of the disease in the community.

What percentage of AQP4-ab-negative NMOSD patients are MOG-ab positive? A study from the Argentinean multiple sclerosis registry (RelevarEM)

BACKGROUND

Myelin oligodendrocyte glycoprotein antibodies (MOG-ab) have been described in aquaporin-4-antibodies(AQP4-ab)-negative neuromyelitis optica spectrum disorder (NMOSD) patients. We aimed to evaluate the percentage of AQP4-ab-negative NMOSD patients who are positive for MOG-ab in a cohort of Argentinean patients included in RelevarEM (Clinical Trials registry number NCT03375177).

METHODS

RelevarEM is a longitudinal, strictly observational multiple sclerosis (MS) and NMOSD registry in Argentina. Of 3031 consecutive patients (until March 2020), 165 patients with phenotype of suspected NMOSD, whose relevant data for the purpose of this study were available, were included. Data on demographic, clinical, paraclinical and treatment in AQP4-ab (positive, negative and unknown) and MOG-ab (positive and negative) patients were evaluated.

RESULTS

A total of 165 patients (79 AQP4-Ab positive, 67 AQP4-Ab negative and 19 unknown) were included. Of these, 155 patients fulfilled the 2015 NMOSD diagnostic criteria. Of 67 AQP4-Ab-negative patients, 36 (53.7%) were tested for MOG-Ab and 10 of them (27.7%) tested positive. Serum AQP4-ab levels were tested by means of cell-based assay (CBA) in 48 (35.2%), based on tissue-based indirect immunofluorescence assays in 58 (42.6%) and enzyme-linked immunosorbent assay in 4 (2.9%). All MOG-ab were tested by CBA. Optic neuritis (90%) was the most frequent symptom at presentation and optic nerve lesions the most frequent finding (80%) in neuroimaging of MOG-ab-associated disease. Of these, six (60%) patients were under immunosuppressant treatments at latest follow-up.

CONCLUSION

We observed that 27.7% (10/36) of the AQP4-ab-negative patients tested for MOG-ab were positive for this antibody, in line with results from other world regions.

Application of the 2015 neuromyelitis optica spectrum disorders diagnostic criteria in a cohort of Chinese patients

BACKGROUND

There is no validation study evaluating 2015 International Panel for neuromyelitis optica (NMO) spectrum disorders (NMOSD) diagnosis (IPND) criteria in Chinese population. The association of myelin oligodendrocyte glycoprotein-immunoglobulin-G (MOG-IgG) with NMOSD was also not investigated in previous validation studies. Hence, we aimed to validate the 2015 NMOSD criteria in a cohort of Chinese patients, and to assess the association between MOG-IgG and NMOSD.

METHODS

We applied both the 2006 NMO and the 2015 NMOSD diagnostic criteria to all suspected NMOSD inpatients at the Department of Neurology of Chinese PLA general hospital diagnosed between 2016 and 2019. Demographics, core clinical features, AQP4-IgG and MOG-IgG status were retrieved and analyzed.

RESULTS

A total of 185 patients fulfilling the 2015 NMOSD criteria (154 AQP4-IgG positive, 23 AQP4-IgG negative, 8 AQP4-IgG status unknown) were included, whereas only 43.2% (80/185) fulfilled the 2006 NMO criteria. After assuming all the NMOSD patients with unknown AQP4-IgG status, 69.7% (129/185) still fulfilled the 2015 NMOSD criteria, whereas only 39.5% (73/185) met the 2006 NMO diagnostic criteria (p < 0.001). Most NMOSD patients (n = 55, 29.7%) disqualified because of not meeting the criterion of dissemination in space. The median time to diagnosis was 3 months (129 patients, range: 1-145 months) by the 2015 NMOSD criteria and 10 months (73 patients, range: 1-185 months) by the 2006 NMO criteria (log rank test: p = 0.002). Positive MOG-IgG was found in 28.6% (4/14) of the AQP4-IgG negative and 2.8% (1/36) of the AQP4-IgG positive NMOSD patients (p = 0.006). NMOSD with MOG-IgG was more frequently in male (3/1 vs. 2/33, p = 0.004) and with younger onset age (24.8 vs. 41.4, p = 0.045), in comparison with NMOSD with AQP4-IgG.

CONCLUSION

The 2015 NMOSD criteria markedly improved the diagnostic rate and reduced the time taken to diagnosis in a cohort of Chinese patients, even with unknown AQP4-IgG status, in comparison with the 2006 NMO criteria. Not meeting the criterion of dissemination in space, that is, having isolated core clinical feature, was the main factor precluding NMOSD diagnosis under assumption of unknown AQP4-IgG status. NMOSD with MOG-IgG was not uncommon in NMOSD without AQP4-IgG and had unique features regarding gender predominance and onset age.

The 2015 IPND Criteria Increases the Yield in Diagnosis of Neuromyelitis Optica Spectrum Disorder in Thai Patients Compared to the 2006 Diagnostic Criteria

BACKGROUND

The 2015 International Panel for Neuromyelitis Optica (NMO) Diagnosis (IPND) criteria was revised using systematic literature reviews and consensus from the experts. It facilitates NMOSD diagnosis and is applicable in an Asian population.

OBJECTIVE

To compare the utility of the 2015 IPND criteria and the 2006 NMO diagnostic criteria for the diagnosis of NMO/SD.

METHODS

We retrospectively reviewed the electronic medical records 5 of patients with NMOSD who attended Multiple Sclerosis and Related Disorders Clinic between January 2010 and December 2016. Two independent investigators applied the 2006 revised diagnostic criteria for NMO in patients who fulfilled the 2015 IPND criteria.

RESULTS

Of all 70 cases who had an NMOSD diagnosis according to 2015 criteria, 56 cases (80.0%) were positive for aquaporin-4 immunoglobulin (AQP4-IgG). Nineteen patients (27.1%) fulfilled the 2006 NMO diagnostic criteria. The 2015 IPND criteria identified 51 more NMOSD cases, increasing the diagnostic yield by 268%, compared to the 2006 criteria. The median time from onset to diagnosis by using the 2015 IPND criteria was shorter than those identified by the 2006 criteria (128 vs. 547 days, p=0.002). The 2015 IPND also provides for lesser attacks occurring before achieving diagnosis (1.7 vs. 2.7, p<0.001). In the absence of known AQP4-IgG serostatus, the 2015 criteria still indicated NMOSD patients by a 124% increase in detection rate (p<0.001); however, time to diagnosis was not statistically significant between the two criteria (258 vs. 604 days, p=0.081).

CONCLUSIONS

Compared to the 2006 criteria, the 2015 IPND criteria increased diagnostic yield for NMOSD regardless of AQP4-IgG status and shortened the time from onset to diagnosis in patients with NMOSD with known AQP4-IgG serostatus.

Clinical and radiological profile of neuromyelitis optica spectrum disorders in an Ecuadorian cohort

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is a complex disease characterized by a severe inflammation of the central nervous system (CNS). This disease typically manifests with recurrent optic neuritis (ON) and acute transverse myelitis (ATM). The clinical and radiological spectrum of NMOSD is little known in Latin America (LATAM) and few reports have been published in the literature so far. In Ecuador, no reports on NMOSD have been published. For this reason we aimed to assess the demographic, clinical and imaging characteristics of patients with NMOSD from third level hospitals from Ecuador.

METHODS

This is a descriptive study in which we assessed medical reports of patients with inflammatory demyelinating diseases who were attended in third level hospitals from Ecuador in 2017. Then we applied the 2015 diagnostic criteria, those patients who met the new NMOSD diagnostic criteria were selected and analyzed. Additionally, exploratory sub-analyses were subsequently carried out.

RESULTS

We identified 59 patients with NMOSD, the relative frequency of NMOSD was 15.9%. The multiple sclerosis (MS) /NMOSD ratio was 5.2:1. Twenty four percent of patients were newly defined as having NMOSD when 2015 criteria was applied. The median time to diagnoses was shorter by the 2015 criteria than 2006 criteria (p<0.001). NMOSD was more prevalent in women (female/male ratio 4.4:1). The disease onset was more frequent at the fourth decade of life. The most common symptoms at the disease onset were ON and the association of ON with ATM. The mean of expanded disability status scale (EDSS) was 4.8 (SD±1.8). Concomitant autoimmune diseases were infrequent in this population (11.9%). The brain magnetic resonance imaging (MRI) abnormalities were present in 25.7% of patients at disease onset. Spinal cord MRI showed longitudinally extensive transverse myelitis (LETM) in 91.5% of cases. Recurrent NMOSD was frequent in this cohort (88%). Positivity for antibodies against aquaporin-4 (AQP4-IgG) which was measured through indirect immunofluorescence assay (IIF) was identified in 81% of the patients tested. Patients with seronegative AQP4-IgG had higher grade of disability than seropositive patients (p<0.05). Ninety eight percent of patients received treatment with immunosuppressive drugs. Three patients died due to gastric cancer (1 patient) and infectious diseases (2 patients).

CONCLUSIONS

This is the first descriptive study in an Ecuadorian cohort of patients with NMOSD. We show a wide epidemiological, clinical and radiological spectrum of NMOSD.

Late Onset of Neuromyelitis Optica Spectrum Disorders

INTRODUCTION

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune demyelinating disease of the central nervous system. NMOSD starting after the age of 50 years is considered a "late onset" (LO-NMOSD) and seems to be particularly aggressive. The objective of this paper is to present a series of 37 Brazilian patients with LO-NMOSD.

METHODS

Retrospective data collection from medical records of patients with LO-NMOSD seen at 14 Brazilian specialized units.

RESULTS

The ratio of women to men in the sample was 4.3 to 1. The patients were followed up for a median period of 4 years. Sex, age at disease onset, and ethnic background were not associated with the number of relapses or disability outcomes. Extensive longitudinal myelitis affected 86% of patients, while optic neuritis affected 70%, and brainstem syndromes were present in only 16% of these patients. Six patients are currently using some type of support for walking or are wheelchair-bound. Three have died. Therapeutic options for NMOSD were particularly complicated for these elderly patients, since medications for controlling NMOSD are, in essence, immunosuppressive. Long-term use of corticosteroids can be an issue when the patients have high blood pressure, diabetes mellitus, or dyslipidemia (conditions often seen in elderly individuals).

CONCLUSION

This series of LO-NMOSD cases highlights the importance of prompt diagnosis and treatment for these patients.

Brain and spinal MRI features distinguishing MS from different AQP4 antibody serostatus NMOSD at disease onset in a cohort of Latin American patients

OBJECTIVE

We aimed to evaluate magnetic resonance imaging (MRI) previously used criteria (Matthews's criteria, MC) for differentiating multiple sclerosis (MS) from neuromyelitis optica spectrum disorders (NMOSD) in Caucasian and non-Caucasian populations (Argentina, Brazil and Venezuela) with positive (P-NMOSD), negative (N-NMOSD), and unknown (U-NMOSD) aquaporin-4 antibody serostatus at disease onset and to assess the added diagnostic value of spinal cord MRI in these populations.

METHODS

We reviewed medical records, and MRIs were assessed by two blinded evaluators and were scored using MC. Short-segment transverse myelitis (STM) was added as a new criterion. MC sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were determined.

RESULTS

We included 282 patients (MS = 188 and NMOSD = 94). MC applied to the entire cohort showed 97.8% sensitivity, 82.9% specificity, 92.0% PPV, and 95.1% NPV for differentiating MS from NMOSD. A subanalysis applied only to non-Caucasian (MS = 89 and NMOSD = 47) showed 100% sensitivity, 80.8% specificity, 90.8% PPV, and 100% NPV. Similar sensitivity, specificity, PPV, and NPV of MC for MS versus P-NMOSD (n = 55), N-NMOSD (n = 28), and U-NMOSD (n = 21) were observed.

CONCLUSION

MC distinguished MS from NMOSD of all serostatus in a Latin American cohort that included non-Caucasian populations. Addition of STM to MC did not raise the accuracy significantly.

Clinical characteristics of 153 Brazilian patients with neuromyelitis optica spectrum disorder (NMOSD)

BACKGROUND

The 2015 criteria for diagnosing neuromyelitis optica spectrum disorder (NMOSD) have encouraged several groups across the world to report on their patients using these criteria. The disease typically manifests with severe relapses of optic neuritis, longitudinally extensive myelitis and/or brainstem syndromes, often leading to severe disability. Some patients are seropositive for antibodies against aquaporin-4 (AQP4), others are positive for anti-myelin oligodendrocyte glycoprotein (MOG), while a few are negative for both biomarkers. The disease is complex, and only now are specific therapeutic clinical trials being carried out. The present study adds to the literature through detailed clinical data from 153 medical records of Brazilian patients.

METHODS

Retrospective assessment of medical records from nine specialized units in Brazil.

RESULTS

NMOSD was more prevalent in females (4.1:1), who had significantly fewer relapses than males (p = 0.007) but presented similar levels of disability over time. African ancestry was associated with higher levels of disability throughout the disease course (p < 0.001), although the number of relapses was similar to that observed in white patients. Concomitant autoimmune diseases were relatively rare in this population (6.5%). Positivity for anti-AQP4 antibodies was identified in 62% of the patients tested, while 3% presented anti-MOG antibodies. Anti-AQP4 antibodies were not associated to worse disease course. The last medical record showed that six patients had died and 13 were wheelchair-bound. Seventy percent of the patients did not respond to first-line therapy (azathioprine and/or corticosteroids), and five patients continued to relapse even after four different courses of treatment.

CONCLUSION

The present study adds to the reports from other countries presenting original data on Brazilian patients diagnosed with NMOSD according to the 2015 criteria.