Clinical outcomes and prognostic factors in patients with optic neuritis related to NMOSD and MOGAD in distinct ethnic groups from Latin America.

BACKGROUND: Optic neuritis (ON) can be an initial manifestation of neuromyelitis optica spectrum disorder (NMOSD) associated with aquaporin 4-antibody (AQP4-Ab) or myelin oligodendrocyte glycoprotein antibody (MOG-Ab)-associated disease (MOGAD). Additionally, both diseases may have overlapping paraclinical and radiological features. These diseases may have different outcomes and prognoses. We aimed to compare clinical outcomes and prognostic features of patients with NMOSD and MOGAD presenting ON as first attack, from different ethnic groups in Latin America. METHODS: We conducted a retrospective observational multicenter study in patients from Argentina (n = 61), Chile (n = 18), Ecuador (n = 27), Brazil (n = 30), Venezuela (n = 10) and Mexico (n = 49) with MOGAD or NMOSD related ON. Predictors of disability outcomes at last follow-up, namely visual disability (Visual Functional System Score ≥4), motor disability (permanent inability to walk further than 100 m unaided) and wheelchair dependence based on EDSS score were evaluated. RESULTS: After a mean disease duration of 42.7 (±40.2) months in NMOSD and 19.7 (±23.6) in MOGAD, 55% and 22% (p>0.001) experienced permanent severe visual disability (visual acuity from 20/100 to 20/200), 22% and 6% (p = 0.01) permanent motor disability and 11% and 0% (p = 0.04) had become wheelchair dependent, respectively. Older age at disease onset was a predictor of severe visual disability (OR=1,03 CI95%1.01-1.05, p = 0.03); older age at disease onset (OR=1,04 CI95%1.01-1.07, p = 0.01), higher number of relapses (OR=1,32 CI95%1.02-1.71, p = 0.03) and rituximab treatment (OR=0,36 CI95%0.14-0.90, p = 0.02) were predictors of permanent motor disability, whereas ON associated with myelitis at disease onset was a predictor of wheelchair dependency (OR=4,16, CI95%1.23-14.08, p = 0,02) in NMOSD patients. No differences were found when evaluating distinct ethnic groups (Mixed vs. Caucasian vs. Afro-descendant) CONCLUSIONS: NMOSD was associated with poorer clinical outcomes than MOGAD. Ethnicity was not associated with prognostic factors. Distinct predictors of permanent visual and motor disability and wheelchair dependency in NMOSD patients were found.

Therapeutic strategies in NMOSD and MOGAD patients: A multicenter cohort study in Latin America.

PURPOSE: This study describes the therapeutic strategies in NMOSD and MOGAD adopted by neurologists to treat both conditions in Latin America (LATAM) with main focus on rituximab (RTX) and the disease outcome. METHODS: retrospective study in a cohort of NMOSD and MOGAD patients followed in specialized MS/NMOSD centers from eight countries and 14 LATAM reference centers. Demographics and clinical characteristics were collected. RTX strategies on naïve (for rituximab) patients were summarized as follows: scheme A: two 1000 mg infusions 15 days apart and repeated every 6 months; scheme B: four 375 mg/m2 infusions every week for 4 weeks and repeated every 6 months; scheme C: one 1000 mg infusions and repeated every 6 months; scheme D: other scheme used. Relapse rate and adverse events during follow-up were analyzed considering the different RTX schemes. Poisson and logistic regression analysis were used to assess baseline aspects and disease activity during follow-up. RESULTS: A total of 217 patients were included. 197 were NMOSD patients (164, 83.2% AQP4-IgG seropositive and 16.7% seronegative) and 20 were MOGAD patients. The most frequent long-term treatment was RTX in both groups (48.2% and 65% for NMOSD and MOGAD patients, respectively). The most common RTX regimen used in 79 (83.1%) patients was two 1000 mg infusions 15 days apart and repeat every 6 months. Relapses under RTX treatment were observed in 21 (22.1%) patients. Relapses after RTX treatment were associated with higher EDSS (OR 1.75, 95%CI 1.44-2.34, p = 0.03) and higher ARR pre-RTX (OR = 2.17, 95% CI 1.72-3.12, p = 0.002) but not with RTX regimen (OR = 1.10, 95% CI 0.89-1.21, p = 0.60). CONCLUSION: the most strategy used in LATAM was RTX with two 1000 mg infusions 15 days apart. Relapses during follow up were not associated with RTX regimen used.

Chiasmatic lesions on conventional magnetic resonance imaging during the first event of optic neuritis in patients with neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein-associated disease in a Latin American cohort.

BACKGROUND AND PURPOSE: Optic neuritis (ON) is often the initial symptom of neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein-associated disease (MOGAD). We aimed to compare the frequency and pattern of chiasmatic lesions in MOGAD-related ON (MOGAD-ON) and NMOSD-related ON (NMOSD-ON) using conventional brain imaging (magnetic resonance imaging [MRI]) in Latin America (LATAM). METHODS: We reviewed the medical records and brain MRI (≤30 days from ON onset) of patients with a first event of MOGAD-ON and NMOSD-ON. Patients from Argentina (n = 72), Chile (n = 21), Ecuador (n = 31), Brazil (n = 30), Venezuela (n = 10) and Mexico (n = 82) were included. Antibody status was tested using a cell-based assay. Demographic, clinical, imaging and prognostic (as measured by the Visual Functional System Score [VFSS] of the Expanded Disability Status Scale) data were compared. RESULTS: A total of 246 patients (208 NMOSD and 38 MOGAD) were included. No differences were found in gender and ethnicity between the groups. We observed chiasmatic lesions in 66/208 (31.7%) NMOSD-ON and in 5/38 (13.1%) MOGAD-ON patients (p = 0.01). Of these patients with chiasmatic lesions, 54/66 (81.8%) and 4/5 had associated longitudinally extensive optic nerve lesions, 45/66 (68%) and 4/5 had bilateral lesions, and 31/66 (47%) and 4/5 showed gadolinium-enhancing chiasmatic lesions, respectively. A positive correlation was observed between VFSS and presence of bilateral (r = 0,28, p < 0.0001), chiasmatic (r = 0.27, p = 0.0001) and longitudinally extensive lesions (r = 0,25, p = 0.0009) in the NMOSD-ON group, but no correlations were observed in the MOGAD-ON group. CONCLUSIONS: Chiasmatic lesions were significantly more common in NMOSD than in MOGAD during an ON attack in this LATAM cohort. Further studies are needed to assess the generalizability of these results.

Perfil clínico y epidemiológico de los pacientes con diagnóstico de neuromielitis óptica / Clinical and epidemiological profile of patients with neuromyelitis optica diagnosis

INTRODUCCIÓN. El trastorno del espectro de neuromielitis óptica, enfermedad inflamatoria, desmielinizante, afecta al sistema nervioso central, frecuente en poblaciones no caucásicas como la ecuatoriana. El retraso en su diagnóstico y tratamiento provoca discapacidad que se puede prevenir. OBJETIVO. Determinar el perfil clínico y epidemiológico de los pacientes con diagnóstico de trastorno del espectro de neuromielitis óptica. MATERIALES Y MÉTODOS. Estudio descriptivo transversal. Población de 45 Historias Clínicas y una muestra de 41 de pacientes con diagnóstico de trastorno del espectro de neuromielitis óptica atendidos en la Unidad de Neurología del Hospital de Especialida-des Carlos Andrade Marín, período enero 2005 a diciembre 2019. Se realizó análisis univarial. Se aplicó el programa estadístico International Business Machines Statistical Package for the Social Sciences, versión 25. RESULTADOS. El 76,0% (31; 41) fueron mujeres. Datos promedios: edad 48,9 años; diagnóstico definitivo demoró 4,12 años, desde el inicio de los síntomas; tiempo de diagnóstico fue 3,17 años; 3,7 brotes en total; el 87,8% (36; 41) con un fenotipo recurrente. La media de duración de la enfermedad fue de 6,8 años. En el 70,7% (29; 41), se identificaron anticuerpos anti-AQP4 en suero mediante inmunofluorescencia directa, el 51,2% requirieron para la marcha apoyo uni o bilateral. El 43,9% (18; 41) debutó con neuritis óptica; el 31,7% (13; 41) presentaron mielitis como primer síntoma y el 24,4% (10; 41) la combinación de neuritis óptica y mielitis fueron los síntomas iniciales. CONCLUSIÓN. Se determinó el perfil clínico y epi-demiológico de los pacientes con diagnóstico de trastorno del espectro de neuromielitis óptica. Existió demora en el diagnóstico definitivo de los pacientes desde el inicio de los síntomas, lo que se tradujo en un aumento de la discapacidad.

INTRODUCTION. Neuromyelitis optica spectrum disorder, an inflammatory, demyelinating disease, affects the central nervous system, common in non-Caucasian popu-lations such as Ecuadorians. The delay in its diagnosis and treatment causes disabi-lity that can be prevented. OBJECTIVE. To determine the clinical and epidemiological profile of patients diagnosed with neuromyelitis optica spectrum disorder. MATERIALS AND METHODS. Cross-sectional descriptive study. Population of 45 Medical Records and a sample of 41 patients with a diagnosis of neuromyelitis optica spectrum disor-der seen at the Neurology Unit of the Carlos Andrade Marín Specialties Hospital, period from January 2005 to December 2019. Univariate analysis was performed. The statistical program International Business Machines Statistical Package for the Social Sciences, version 25 was used. RESULTS. 76,0% (31; 41) were women. Average data: age 48,9 years; definitive diagnosis took 4,12 years from the onset of symptoms; time to diagnosis was 3,17 years; 3,7 outbreaks in total; 87,8% (36; 41) with a recurrent phenotype. The average disease duration was 6,8 years. In 70,7% (29; 41), anti-AQP4 antibodies were identified in serum by direct immunofluorescence, 51,2% required uni- or bilateral su-pport for walking. Optic neuritis started in 43,9% (18; 41); 31,7% (13; 41) had myelitis as the first symptom and 24,4% (10; 41) the combination of optic neuritis and myelitis were the initial symptoms. CONCLUSION. The clinical and epidemiological profile of patients diagnosed with neuromyelitis optica spectrum disorder was determined. There was delay in the conclusive diagnosis of patients from the beginning of symptoms, which resulted in increased disability.