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.

Impact of rituximab in Mexican patients with Multiple Sclerosis-A single-center retrospective study.

BACKGROUND: Multiple Sclerosis (MS) is a chronic autoimmune disease of the central nervous system (CNS). B cells have an essential role in the disease pathogenesis and therefore selective B-cell depletion are commonly used to treat the disease. Rituximab (RTX), a chimeric anti-CD20 monoclonal antibody had demonstrated reduced inflammatory activity and radiological activity in MS patients. Due to economic constrains and treatment access limitations, RTX is often used as a treatment alternative in these patients. Here, we described our center experience in RTX -treated MS patients. METHODS: A single-center observational retrospective study was conducted in a Mexican cohort MS during 2010 to 2020. All patients had a confirmed MS diagnosis.All patients received fixed scheme involving induction with 1 g on day one and day 15, followed by 500 mg-1 g every six months for maintenance. Annual Relapse Rate (ARR), Progression index (PI), Expanded Disability Status Scale (EDSS) and MRI activity of the disease were evaluated. Comparison between naïve and non-naïve patients was also conducted. RESULTS: A total of 85 patients were included. The mean age at diagnosis was 33.13 (±8.90) years with 73 (85.9%) being RRMS. 39 (34.1%) were treatment-naïve. While treated with RTX, 62(72.9%) patients reached a free-of-relapse status, with statistically significant decrease in the mean ARR from 0.82 to 0.36 [0.14 (95%CI: 0.09-0.20), p = 0.0001 and EDSS [0.25 CI 0-0.5 (p = 0.034)] and a decrease in their T1 Gd-enhancing MRI lesions (1.64 vs. 0.12 CI 0.70-2.30, p = 0.004. 29 (29.4%) patients achieved NEDA-3. Among all patients, only 2 (2.4%) experienced infusion-related mild adverse events. No serious adverse events were reported. CONCLUSION: We found significant clinical and radiological improvement in naïve and non-naïve MS patients treated with RTX.

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.

Increased non-attendance at epilepsy clinic in patients with neuropsychiatric comorbidities: A prospective study.

BACKGROUND: In patients with epilepsy, regular follow-up is vital for adequate seizure control, antiseizure drugs' (ASDs) side effects, psychiatric comorbidities, and planning for epilepsy surgery. Non-attendance creates barriers to adequate patient care, inefficient allocation of resources, loss of income, and unnecessary emergency department visits due to lack of seizure control. This study aimed to determine the causes and sociodemographic characteristics of the non-attendant population at the Epilepsy Clinic. METHODS: A prospective and observational study was carried out on patients treated at the Epilepsy Clinic of the National Institute of Neurology and Neurosurgery (NINN) in Mexico from August 2015 to June 2016. A phone interview was made with all those patients who did not attend the epilepsy consultation. This call incorporated ad hoc questions to meet the objectives of this study. RESULTS: During the study period, 1299 patients had an appointment at the epilepsy clinic, where 233 (17.9%) patients missed their consultation, 123 (52.8%) were male, mean age was 35.9 ±â€¯14.42 years. The most frequent cause of non-attendance was forgetfulness of the appointment in 62 patients (26.6%). Two patients died; no patient was reported to have experienced SUDEP. Non-attendant patients showed statistically significant overall prevalence of psychiatric comorbidities (41.6%), particularly depression, anxiety, and interictal psychosis. CONCLUSION: Information on non-attendance at various specialist consultations is scarce, and to our knowledge, this is the first study to address non-attendance in patients with epilepsy in Latin America. Improving hospital protocols to reduce non-attendance can increase patient adherence to follow-up, ultimately improving the quality of care in the epilepsy clinic.

Clinical experience of plasmapheresis for neuromyelitis optica patients in Mexico.

BACKGROUND: Neuromyelitis optica spectrum disorders (NMOSDs) are a group of chronic immune-mediated demyelinating diseases of the central nervous system. Their pathophysiology dependent on humoral mediated responses caused by autoreactive IgG antibodies against aquaporin-4 water channels (AQP4-IgG) or myelin oligodendrocyte glycoprotein (MOG-IgG). Plasma exchange (PLEX) has proved to be a beneficial therapy in patients with severe relapses. We present the largest series of Latin American patients treated with PLEX for acute NMOSDs relapses. METHODS: A retrospective study was conducted. Selection included patients diagnosed with NMOSDs who received PLEX between 2010-2019, irrespective of their AQP4-IgG serostatus. All patients received 5 grams of IV methylprednisolone. PLEX therapy could be initiated simultaneously or after IV steroids. Baseline and post-PLEX therapy Expanded Disability Status Scale (EDSS) was measured to identify acute response to therapy. Comparison between responders and non-responders was also conducted. Subgroup analysis stratified response by serostatus, type of clinical relapse and time to PLEX. RESULTS: A total of 89 patients were included. Mean age at onset was 38 ± 12.97 years. 49 (55.1%) patients were AQP4-IgG seropositive. Most patients had unilateral optic neuritis (34.8%) or longitudinally extensive transverse myelitis (33.7%). Mean time from onset to PLEX initiation was 20.9 ± 18.1 days. Response rate was 39.3% and mean decline in EDSS was 0.7 ± 0.9 (p <0.001). Decline in EDSS and response rate were independent of serostatus, type of clinical relapse or time to PLEX initiation. CONCLUSION: PLEX appears to be an effective therapy for NMOSDs relapses even in limited resources setting where treatment initiation may be delayed. The benefit seems to be independent of the type of clinical relapse and AQP4 IgG serostatus.

A comparison of waiting times for assessment and epilepsy surgery between a Canadian and a Mexican referral center.

Objective: To provide a comprehensive transnational overview of wait times for epilepsy surgery in Canada and Mexico. Methods: We reviewed all cases referred for epilepsy surgery between 2007 and 2015 at the Saskatchewan Epilepsy Program Royal University Hospital (SEP) (n = 70; Saskatoon, Canada) and the National Institute of Neurology and Neurosurgery (NINN) (n = 76; Mexico City, Mexico) and compared wait times, calculated as the time from diagnosis of epilepsy on assessment at an epilepsy center to epilepsy surgery. Results: Mean wait times were similar across centers. Mean patient age was 37.4 ± 9 years (NINN) and 36.7 ± 13.2 years (SEP). The mean time from epilepsy diagnosis to referral was 18.9 (NINN) and 16.9 years (SEP), p = 0.30; first consult with the epileptologist, 19.7 (NINN) and 17.4 years (p = 0.23); neuropsychology consult, 21.4 (NINN) and 17.9 years (SEP); video electroencephalogram (video-EEG) telemetry, 21.1 (NINN) and 18.6 months (SEP); initial neurosurgical consult, 21.9 (NINN) and 19.1 years (SEP) (p = 0.35); and epilepsy surgery, 19.7 (NINN) and 19.6 years (SEP) (p = 0.29). Significance: This is the first study to compare wait times between Canada and Mexico. Despite disparity in their health delivery systems and financial resources, surgical wait times appeared to be protracted in both nations, confirming that delayed treatment is a universal problem that requires collaborative scrutiny.