Oligoclonal IgM bands in the cerebrospinal fluid of patients with relapsing MS to inform long-term MS disability.

BACKGROUND: Prognostic markers are needed to guide multiple sclerosis (MS) management in the context of large availability of disease-modifying drugs (DMDs). OBJECTIVE: To investigate the role of cerebrospinal fluid (CSF) markers to inform long-term MS outcomes. METHODS: Demographic features, IgM index, oligoclonal IgM bands (OCMB), lipid-specific OCMB, CSF neurofilament light chain protein levels, expanded disability status scale (EDSS), relapses and DMD use over the study period and peripapillary retinal nerve fiber layer (pRNFL) and ganglion cell plus inner plexiform layer (GCIPL) thicknesses in non-optic neuritis eyes (end of follow-up) were collected from relapsing MS (RMS) patients with CSF obtained ⩽2 years after MS onset prospectively followed at the Hospital Clinic of Barcelona. We assessed associations between CSF markers and MS outcomes using multivariable models. RESULTS: A total of 89 patients (71 females; median 32.9 years of age) followed over a median of 9.6 years were included. OCMB were associated with a 33% increase in the annualized relapse rate (ARR; p = 0.06), higher odds for high-efficacy DMDs use (OR = 4.8; 95% CI = (1.5, 16.1)), thinner pRNFL (ß = -4.4; 95% CI = (-8.6, -0.2)) and GCIPL (ß = -2.9; 95% CI = (-5.9, +0.05)), and higher rates to EDSS ⩾ 3.0 (HR = 4.4; 95% CI = (1.6, 11.8)) and EDSS ⩾ 4.0 (HR = 5.4; 95% CI = (1.1, 27.1)). No overall associations were found for other CSF markers. CONCLUSION: The presence of OCMB was associated with unfavorable long-term outcomes. OCMB should be determined in RMS to inform long-term prognosis.

Incidence and Impact of COVID-19 in MS: A Survey From a Barcelona MS Unit.

OBJECTIVE: To investigate the incidence of coronavirus disease 2019 (COVID-19) in a single-center cohort of patients with MS and to explore the contribution of their comorbidities and therapies to the outcome. METHODS: A cross-sectional mixed-method study was conducted involving an email-based, self-administered questionnaire sent on May 21, 2020, to 586 patients with MS followed at the MS Unit of Hospital Clinic, University of Barcelona, along with telephone interview, and review of electronic medical records until June 18, 2020. The cumulative incidence of confirmed COVID-19 (positive PCR or antibody test) and all COVID-19 cases (confirmed and suspected) from the start of the pandemic was compared with the population estimates for Barcelona. RESULTS: A total of 407 patients (69.5%) completed the survey. Most of the responders (67%) were female. The responders had a median age of 48 years (range 19-86), relapsing-remitting disease (84%), at least 1 comorbidity (45%), and were on disease-modifying therapy (DMT; 74.7%). COVID-19 was confirmed in 5 patients (1.2%) and suspected in 46 (11.3%). The cumulative incidence of confirmed COVID-19 cases was similar to that of the general population but was almost 2-fold higher when all cases were considered (p < 0.001). Six patients (11.7%) were hospitalized, of which 5 had good recovery and 1 died. Hospitalized patients were more frequently male, had diabetes and had progressive forms of MS (p < 0.05). DMT was not associated with the risk of infection or the outcome. CONCLUSIONS: In the studied MS cohort, the incidence of COVID-19 was higher than that of the general population; however, most patients did not require hospitalization and had a good outcome despite the frequent presence of comorbidities and treatment with DMT.

Regional grey matter microstructural changes and volume loss according to disease duration in multiple sclerosis patients.

The spatio-temporal characteristics of grey matter (GM) impairment in multiple sclerosis (MS) are poorly understood. We used a new surface-based diffusion MRI processing tool to investigate regional modifications of microstructure, and we quantified volume loss in GM in a cohort of patients with MS classified into three groups according to disease duration. Additionally, we investigated the relationship between GM changes with disease severity. We studied 54 healthy controls and 247 MS patients classified regarding disease duration: MS1 (less than 5 years, n = 67); MS2 (5-15 years, n = 107); and MS3 (more than15 years, n = 73). We compared GM mean diffusivity (MD), fractional anisotropy (FA) and volume between groups, and estimated their clinical associations. Regional modifications in diffusion measures (MD and FA) and volume did not overlap early in the disease, and became widespread in later phases. We found higher MD in MS1 group, mainly in the temporal cortex, and volume reduction in deep GM and left precuneus. Additional MD changes were evident in cingulate and occipital cortices in the MS2 group, coupled to volume reductions in deep GM and parietal and frontal poles. Changes in MD and volume extended to more than 80% of regions in MS3 group. Conversely, increments in FA, with very low effect size, were observed in the parietal cortex and thalamus in MS1 and MS2 groups, and extended to the frontal lobe in the later group. MD and GM changes were associated with white matter lesion load and with physical and cognitive disability. Microstructural integrity loss and atrophy present differential spatial predominance early in MS and accrual over time, probably due to distinct pathogenic mechanisms that underlie tissue damage.

Dynamics and Predictors of Cognitive Impairment along the Disease Course in Multiple Sclerosis.

(1) Background: The evolution and predictors of cognitive impairment (CI) in multiple sclerosis (MS) are poorly understood. We aimed to define the temporal dynamics of cognition throughout the disease course and identify clinical and neuroimaging measures that predict CI. (2) Methods: This paper features a longitudinal study with 212 patients who underwent several cognitive examinations at different time points. Dynamics of cognition were assessed using mixed-effects linear spline models. Machine learning techniques were used to identify which baseline demographic, clinical, and neuroimaging measures best predicted CI. (3) Results: In the first 5 years of MS, we detected an increase in the z-scores of global cognition, verbal memory, and information processing speed, which was followed by a decline in global cognition and memory (p < 0.05) between years 5 and 15. From 15 to 30 years of disease onset, cognitive decline continued, affecting global cognition and verbal memory. The baseline measures that best predicted CI were education, disease severity, lesion burden, and hippocampus and anterior cingulate cortex volume. (4) Conclusions: In MS, cognition deteriorates 5 years after disease onset, declining steadily over the next 25 years and more markedly affecting verbal memory. Education, disease severity, lesion burden, and volume of limbic structures predict future CI and may be helpful when identifying at-risk patients.

Benefit from mechanical thrombectomy in acute ischemic stroke with fast and slow progression.

OBJECTIVE: The rate of progression of the ischemic lesion is variable in patients with stroke. We tested the hypothesis that the tissue saving effect of mechanical thrombectomy (MT) is greater in fast progressors. METHODS: A single-center cohort of consecutive patients (n=242) with occlusions of the terminal internal carotid or M1 segment of the middle cerebral artery treated with MT (n=195) or best medical treatment (n=47), known time from onset, and full imaging (baseline CT perfusion and follow-up MRI) available was studied. The estimated infarct progression rate (eIPR) was calculated at baseline and patients were categorized as fast/slow progressors according to the median eIPR of 4.8 mL/hour. The primary outcome measure was the interaction between eIPR category and MT on infarct growth. The secondary outcomes assessed the effect of MT on final infarct volume and functional status in relation to the eIPR category. The safety outcomes were mortality and symptomatic intracranial hemorrhage. RESULTS: The eIPR category had a modifying effect (Pi=0.017) of MT on infarct growth that was significantly reduced with MT only in fast progressors (median (IQR) 3.8 mL (-11-55) vs 41 mL (11-107) with medical treatment; p=0.009, adjusted p=0.045). There was also a significant interaction on final infarct volume (Pi=0.005), with a greater reduction after MT in fast progressors. The functional status improved with MT both in fast and slow progressors, with no significant modifying effect of eIPR category (Pi=0.201). There were also no significant interactions on safety outcomes. CONCLUSION: MT in stroke patients with large vessel occlusion limits infarct growth more significantly in fast progressors.

Rebound of multiple sclerosis activity after fingolimod withdrawal due to planning pregnancy: Analysis of predisposing factors.

BACKGROUND: Rebound of multiple sclerosis (MS) activity has been described after the withdrawal of high-efficacy drugs, but its impact during pregnancy is less known. We describe a series of cases of rebound syndrome after the cessation of fingolimod due to pregnancy planning. METHODS: The clinical and radiological data of 7 MS patients who discontinued fingolimod therapy between May 2012 and March 2018 to plan a pregnancy was analysed. RESULTS: Three (42.8%) of the 7 patients experienced a rebound effect, all of whom became pregnant. During pregnancy, the 3 patients had a mean (SD) of 5.3 (1.3) relapses, and 13 of the 15 relapses were treated with intravenous steroids and/or immunoglobulin. These patients experienced a median increase of 3 points in the Expanded Disability Status Scale (range, 2-4), as well as a median increase of 27 new gadolinium-enhancing lesions (range, 9-40) and 38 new T2 lesions in a post-partum MRI (range, 21-70). The 3 pregnancies resulted in the delivery of healthy babies. A strong correlation was found between the lymphocyte count at fingolimod onset and the annual relapse rate in the period without therapy (r= -0.84, p = 0.005). The time to first relapse was shorter in patients who had <300/µl lymphocytes at fingolimod onset (median time 46 vs 426 days, p = 0.010). CONCLUSION: Rebound activity after fingolimod suspension represents a severe long-lasting inflammatory syndrome that may affect up to 40% of female MS patient who discontinue therapy due to pregnancy planning. Lymphopenia (<300/µl) in the first 3 months of fingolimod onset may predispose patients to suffer earlier and higher disease activity upon cessation.

Impact of Cognitive Reserve and Structural Connectivity on Cognitive Performance in Multiple Sclerosis.

Background: Cognitive reserve (CR) could attenuate the impact of the brain burden on the cognition in people with multiple sclerosis (PwMS). Objective: To explore the relationship between CR and structural brain connectivity and investigate their role on cognition in PwMS cognitively impaired (PwMS-CI) and cognitively preserved (PwMS-CP). Methods: In this study, 181 PwMS (71% female; 42.9 ± 10.0 years) were evaluated using the Cognitive Reserve Questionnaire (CRQ), Brief Repeatable Battery of Neuropsychological tests, and MRI. Brain lesion and gray matter volumes were quantified, as was the structural network connectivity. Patients were classified as PwMS-CI (z scores = -1.5 SD in at least two tests) or PwMS-CP. Linear and multiple regression analyses were run to evaluate the association of CRQ and structural connectivity with cognition in each group. Hedges's effect size was used to compute the strength of associations. Results: We found a very low association between CRQ scores and connectivity metrics in PwMS-CP, while in PwMS-CI, this relation was low to moderate. The multiple regression model, adjusted for age, gender, mood, lesion volume, and graph metrics (local and global efficiency, and transitivity), indicated that the CRQ (ß = 0.26, 95% CI: 0.17-0.35) was associated with cognition (adj R 2 = 0.34) in PwMS-CP (55%). In PwMS-CI, CRQ (ß = 0.18, 95% CI: 0.07-0.29), age, and network global efficiency were independently associated with cognition (adj R 2 = 0.55). The age- and gender-adjusted association between CRQ score and global efficiency on having an impaired cognitive status was -0.338 (OR: 0.71, p = 0.036) and -0.531 (OR: 0.59, p = 0.002), respectively. Conclusions: CR seems to have a marginally significant effect on brain structural connectivity, observed in patients with more severe clinical impairment. It protects PwMS from cognitive decline regardless of their cognitive status, yet once cognitive impairment has set in, brain damage and aging are also influencing cognitive performance.

Characterization of multiple sclerosis lesions with distinct clinical correlates through quantitative diffusion MRI.

Diffusion magnetic resonance imaging can reveal quantitative information about the tissue changes in multiple sclerosis. The recently developed multi-compartment spherical mean technique can map different microscopic properties based only on local diffusion signals, and it may provide specific information on the underlying microstructural modifications that arise in multiple sclerosis. Given that the lesions in multiple sclerosis may reflect different degrees of damage, we hypothesized that quantitative diffusion maps may help characterize the severity of lesions "in vivo" and correlate these to an individual's clinical profile. We evaluated this in a cohort of 59 multiple sclerosis patients (62% female, mean age 44.7 years), for whom demographic and disease information was obtained, and who underwent a comprehensive physical and cognitive evaluation. The magnetic resonance imaging protocol included conventional sequences to define focal lesions, and multi-shell diffusion imaging was used with b-values of 1000, 2000 and 3000 s/mm2 in 180 encoding directions. Quantitative diffusion properties on a macro- and micro-scale were used to discriminate distinct types of lesions through a k-means clustering algorithm, and the number and volume of those lesion types were correlated with parameters of the disease. The combination of diffusion tensor imaging metrics (fractional anisotropy and radial diffusivity) and multi-compartment spherical mean technique values (microscopic fractional anisotropy and intra-neurite volume fraction) differentiated two type of lesions, with a prediction strength of 0.931. The B-type lesions had larger diffusion changes compared to the A-type lesions, irrespective of their location (P < 0.001). The number of A and B type lesions was similar, although in juxtacortical areas B-type lesions predominated (60%, P < 0.001). Also, the percentage of B-type lesion volume was higher (64%, P < 0.001), indicating that these lesions were larger. The number and volume of B-type lesions was related to the severity of disease evolution, clinical disability and cognitive decline (P = 0.004, Bonferroni correction). Specifically, more and larger B-type lesions were correlated with a worse Multiple Sclerosis Severity Score, cerebellar function and cognitive performance. Thus, by combining several microscopic and macroscopic diffusion properties, the severity of damage within focal lesions can be characterized, further contributing to our understanding of the mechanisms that drive disease evolution. Accordingly, the classification of lesion types has the potential to permit more specific and better-targeted treatment of patients with multiple sclerosis.

Acute lumbar polyradiculoneuropathy as early sign of methotrexate intrathecal neurotoxicity: Case report and literature review.

Acute paraplegia after treatment with intrathecal methotrexate requires a complete spinal cord neuroimaging as well as electrodiagnostic examination. The absence of lumbosacral F waves motor responses without demyelinating findings may indicate early direct root toxicity. Early electromyography (EMG) screening could be a valuable tool for detecting peripheral neurotoxicity.

Greater infarct growth limiting effect of mechanical thrombectomy in stroke patients with poor collaterals.

OBJECTIVE: Stroke patients with good collateral circulation achieve the best recovery after mechanical thrombectomy (MT) but strict imaging selection may result in untreated patients that could benefit from MT. We assessed whether the extent of collaterals had modifying effects on the amount of ischemic tissue saved from infarction with MT over best medical treatment (BMT). METHODS: This was a single center cohort of consecutive patients (n=339) with proximal occlusions in the carotid territory. Patients were categorized according to a four point category scale on CT angiography as having good (scores 2-3) or poor (scores 0-1) collaterals. The primary outcome measure was the interaction between collaterals and MT on infarct growth. The secondary outcome assessed the treatment effect of MT over BMT on functional status in relation to collateral status. Safety outcomes were mortality and symptomatic intracranial hemorrhage. RESULTS: Collaterals had a modifying effect of MT on infarct growth (P=0.004), with a greater reduction in 96 patients with poor collaterals (38.8 mL) than in 243 patients with good collaterals (1.9 mL). There was also a significant (P<0.001) interaction between the effect of MT and functional outcome in relation to collateral status, with more benefits of MT in patients with poor collaterals. MT was associated with lower mortality than BMT in patients with poor collaterals only. CONCLUSION: Compared with BMT, the use of MT in the early time window in large vessel stroke results in a more substantial limitation of infarct growth in patients with poor collaterals.

Modified connectivity of vulnerable brain nodes in multiple sclerosis, their impact on cognition and their discriminative value.

Brain structural network modifications in multiple sclerosis (MS) seem to be clinically relevant. The discriminative ability of those changes to identify MS patients or their cognitive status remains unknown. Therefore, this study aimed to investigate connectivity changes in MS patients related to their cognitive status, and to define an automatic classification method to classify subjects as patients and healthy volunteers (HV) or as cognitively preserved (CP) and impaired (CI) patients. We analysed structural brain connectivity in 45 HV and 188 MS patients (104 CP and 84 CI). A support vector machine with k-fold cross-validation was built using the graph metrics features that best differentiate the groups (p < 0.05). Local efficiency (LE) and node strength (NS) network properties showed the largest differences: 100% and 69.7% of nodes had reduced LE and NS in CP patients compared to HV. Moreover, 55.3% and 57.9% of nodes had decreased LE and NS in CI compared to CP patients, in associative multimodal areas. The classification method achieved an accuracy of 74.8-77.2% to differentiate patients from HV, and 59.9-60.8% to discriminate CI from CP patients. Structural network integrity is widely reduced and worsens as cognitive function declines. Central network properties of vulnerable nodes can be useful to classify MS patients.

Late-onset neuromyelitis optica spectrum disorder: The importance of autoantibody serostatus.

OBJECTIVE: To describe the clinical features of late-onset (≥50 years) neuromyelitis optica spectrum disorder (LO-NMOSD), to compare the outcome with that of early-onset (EO-NMOSD), and to identify predictors of disability. METHODS: A retrospective, multicenter study of 238 patients with NMOSD identified by the 2015 criteria. Clinical and immunologic features of patients with LO-NMOSD were compared with those with EO-NMOSD. All patients were evaluated for aquaporin-4 (AQP4-IgG) and myelin oligodendrocyte glycoprotein (MOG-IgG) antibodies. RESULTS: Sixty-nine (29%) patients had LO-NMOSD. Demographic features, initial disease presentation, annualized relapse rate, and frequency of AQP4-IgG and MOG-IgG did not differ between patients with LO-NMOSD and EO-NMOSD. Among patients with AQP4-IgG or double seronegativity, those with LO-NMOSD had a higher risk to require a cane to walk (hazard ratio [HR], 2.10, 95% CI 1.3-3.54, p = 0.003 for AQP4-IgG, and HR, 13.0, 95% CI 2.8-59.7, p = 0.001, for double seronegative). No differences in outcome were observed between patients with MOG-IgG and LO-NMOSD or EO-NMOSD. Older age at onset (for every 10-year increase, HR 1.63, 95% CI 1.35-1.92 p < 0.001) in NMOSD, and higher disability after the first attack (HR 1.68, 95% CI 1.32-2.14, p < 0.001), and double seronegativity (HR 3.74, 95% CI 1.03-13.6, p = 0.045) in LO-NMOSD were the main independent predictors of worse outcome. CONCLUSIONS: Patients with LO-NMOSD have similar clinical presentation but worse outcome than EO-NMOSD when they are double seronegative or AQP4-IgG positive. Serostatus and residual disability after first attack are the main predictors of LO-NMOSD outcome.

Combined walking outcome measures identify clinically meaningful response to prolonged-release fampridine.

BACKGROUND: Gait impairment is common in multiple sclerosis (MS) and negatively impacts patients' health-related quality of life (HRQoL). Prolonged-release fampridine (PR-fam) improves walking speed, but it is unclear which walking measures are the most suitable for identifying treatment response. Our aim was to assess the effect of PR-fam and the outcome measures that best identify short- and long-term clinically meaningful response. METHODS: We conducted a prospective study in 32 MS patients treated with PR-fam for a year. The assessments at 2 weeks, 3, 6 and 12 months included: timed 25-foot walk (T25FW), 6-minute walk test (6MWT), MS Walking Scale-12 (MSWS-12), a five-level version of the EuroQoL-5 dimensions, and accelerometry. PR-fam response was defined as an improvement in T25FW ⩾20%. RESULTS: Twenty-five (78%) patients were considered responders after 2 weeks of PR-fam and improved significantly in all measures. Responders to T25FW and MSWS-12 (n = 19) showed a significant improvement in HRQoL and accelerometer data compared with responders only to T25FW (n = 6). At 1 year, 15/20 (75%) patients remained responders, but only those with permanent response to T25FW and MSWS-12 (n = 8; 53%) showed a significant improvement in 6MWT and HRQoL. CONCLUSION: The combination of T25FW and MSWS-12 identify better those patients with a clinically significant benefit of PR-fam.

Frequency, symptoms, risk factors, and outcomes of autoimmune encephalitis after herpes simplex encephalitis: a prospective observational study and retrospective analysis.

BACKGROUND: Herpes simplex encephalitis can trigger autoimmune encephalitis that leads to neurological worsening. We aimed to assess the frequency, symptoms, risk factors, and outcomes of this complication. METHODS: We did a prospective observational study and retrospective analysis. In the prospective observational part of this study, we included patients with herpes simplex encephalitis diagnosed by neurologists, paediatricians, or infectious disease specialists in 19 secondary and tertiary Spanish centres (Cohort A). Outpatient follow-up was at 2, 6, and 12 months from onset of herpes simplex encephalitis. We studied another group of patients retrospectively, when they developed autoimmune encephalitis after herpes simplex encephalitis (Cohort B). We compared demographics and clinical features of patients who developed autoimmune encephalitis with those who did not, and in patients who developed autoimmune encephalitis we compared these features by age group (patients ≤4 years compared with patients >4 years). We also used multivariable binary logistic regression models to assess risk factors for autoimmune encephalitis after herpes simplex encephalitis. FINDINGS: Between Jan 1, 2014, and Oct 31, 2017, 54 patients with herpes simplex encephalitis were recruited to Cohort A, and 51 were included in the analysis (median age 50 years [IQR 5-68]). At onset of herpes simplex encephalitis, none of the 51 patients had antibodies to neuronal antigens; during follow-up, 14 (27%) patients developed autoimmune encephalitis and all 14 (100%) had neuronal antibodies (nine [64%] had NMDA receptor [NMDAR] antibodies and five [36%] had other antibodies) at or before onset of symptoms. The other 37 patients did not develop autoimmune encephalitis, although 11 (30%) developed antibodies (n=3 to NMDAR, n=8 to unknown antigens; p<0·001). Antibody detection within 3 weeks of herpes simplex encephalitis was a risk factor for autoimmune encephalitis (odds ratio [OR] 11·5, 95% CI 2·7-48·8; p<0·001). Between Oct 7, 2011, and Oct 31, 2017, there were 48 patients in Cohort B with new-onset or worsening neurological symptoms not caused by herpes simplex virus reactivation (median age 8·8 years [IQR 1·1-44·2]; n=27 male); 44 (92%) patients had antibody-confirmed autoimmune encephalitis (34 had NMDAR antibodies and ten had other antibodies). In both cohorts (n=58 patients with antibody-confirmed autoimmune encephalitis), patients older than 4 years frequently presented with psychosis (18 [58%] of 31; younger children not assessable). Compared with patients older than 4 years, patients aged 4 years or younger (n=27) were more likely to have shorter intervals between onset of herpes simplex encephalitis and onset of autoimmune encephalitis (median 26 days [IQR 24-32] vs 43 days [25-54]; p=0·0073), choreoathetosis (27 [100%] of 27 vs 0 of 31; p<0·001), decreased level of consciousness (26 [96%] of 27 vs seven [23%] of 31; p<0·001), NMDAR antibodies (24 [89%] of 27 vs 19 [61%] of 31; p=0·033), and worse outcome at 1 year (median modified Rankin Scale 4 [IQR 4-4] vs 2 [2-3]; p<0·0010; seizures 12 [63%] of 19 vs three [13%] of 23; p=0·001). INTERPRETATION: The results of our prospective study show that autoimmune encephalitis occurred in 27% of patients with herpes simplex encephalitis. It was associated with development of neuronal antibodies and usually presented within 2 months after treatment of herpes simplex encephalitis; the symptoms were age-dependent, and the neurological outcome was worse in young children. Prompt diagnosis is important because patients, primarily those older than 4 years, can respond to immunotherapy. FUNDING: Mutua Madrileña Foundation, Fondation de l'Université de Lausanne et Centre Hospitalier Universitaire Vaudois, Instituto Carlos III, CIBERER, National Institutes of Health, Generalitat de Catalunya, Fundació CELLEX.