Immunosuppressive therapy in elderly patients with neuromyelitis optica spectrum disorder: a retrospective multicentre study.

BACKGROUND: The risk-benefit relationship of immunosuppressive therapies (ISTs) for elderly patients with neuromyelitis optica spectrum disorder (NMOSD) is not well established. This study aimed to investigate the safety and efficacy of IST in elderly patients with NMOSD. METHODS: This retrospective study analysed IST efficacy and safety in 101 patients with aquaporin-4 antibody-positive NMOSD aged over 65 years, treated for at least 6 months at five Korean referral centres, focusing on relapse rates, infection events and discontinuation due to adverse outcomes. RESULTS: The mean age at disease onset was 59.8 years, and female-to-male ratio was 4:1. Concomitant comorbidities at NMOSD diagnosis were found in 87 patients (86%). The median Expanded Disability Status Scale score at the initiation of IST was 3.5. The administered ISTs included azathioprine (n=61, 60%), mycophenolate mofetil (MMF) (n=48, 48%) and rituximab (n=41, 41%). Over a median of 5.8 years of IST, 58% of patients were relapse-free. The median annualised relapse rate decreased from 0.76 to 0 (p<0.001), and 81% experienced improved or stabilised disability. Patients treated with rituximab had a higher relapse-free rate than those treated with azathioprine or MMF (p=0.022). During IST, 21 patients experienced 25 severe infection events (SIEs) over the age of 65 years, and 3 died from pneumonia. 14 patients (14%) experienced 17 adverse events that led to switching or discontinuation of IST. When comparing the incidence rates of SIEs and adverse events, no differences were observed among patients receiving azathioprine, MMF and rituximab. CONCLUSION: In elderly patients with NMOSD, IST offers potential benefits in reducing relapse rates alongside a tolerable risk of adverse events.

Blood Neurofilament Light Chain and Glial Fibrillary Acidic Protein as Promising Screening Biomarkers for Brain Metastases in Patients with Lung Cancer.

The diagnosis of brain metastases (BMs) in patients with lung cancer (LC) predominantly relies on magnetic resonance imaging (MRI), a method that is constrained by high costs and limited accessibility. This study explores the potential of serum neurofilament light chain (sNfL) and serum glial fibrillary acidic protein (sGFAP) as screening biomarkers for BMs in LC patients. We conducted a retrospective analysis of 700 LC cases at the National Cancer Center, Korea, from July 2020 to June 2022, measuring sNfL and sGFAP levels at initial LC diagnosis. The likelihood of BM was evaluated using multivariate analysis and a predictive nomogram. Additionally, we prospectively monitored 177 samples from 46 LC patients initially without BM. Patients with BMs (n= 135) had significantly higher median sNfL (52.5 pg/mL) and sGFAP (239.2 pg/mL) levels compared to those without BMs (n = 565), with medians of 17.8 pg/mL and 141.1 pg/mL, respectively (p < 0.001 for both). The nomogram, incorporating age, sNfL, and sGFAP, predicted BM with an area under the curve (AUC) of 0.877 (95% CI 0.84-0.914), showing 74.8% sensitivity and 83.5% specificity. Over nine months, 93% of samples from patients without BM remained below the cutoff, while all patients developing BMs showed increased levels at detection. A nomogram incorporating age, sNfL, and sGFAP provides a valuable tool for identifying LC patients at high risk for BM, thereby enabling targeted MRI screenings and enhancing diagnostic efficiency.

Validation of the International MOGAD Panel proposed criteria.

With the increased clinical interest in myelin-oligodendrocyte glycoprotein-antibody-associated disease (MOGAD), the international MOGAD panel's proposed criteria were recently released. To evaluate its diagnostic performance, the criteria were applied to a single-center cohort. Among the enrolled 100 patients, 93 fulfilled the criteria throughout the median 24 months of follow-up. All 36 patients with a clear-positive MOG-immunoglobulin G (IgG) satisfied the supporting features, except one who did not undergo magnetic resonance imaging (MRI) scan at disease onset. The criteria also contributed significantly to the confirmation of MOGAD in 57 of 64 patients without clear-positive MOG-IgG. When limited to the first attack, 51 of 61 patients (84%) satisfied the criteria, 4 of whom were initially negative for MOG-IgG. These results support the diagnostic utility of the International MOGAD Panel criteria.

CSF GFAP levels in double seronegative neuromyelitis optica spectrum disorder: no evidence of astrocyte damage.

BACKGROUND: Despite rigorous confirmation with reliable assays, some individuals showing the neuromyelitis optica spectrum disorder (NMOSD) phenotype remain negative for both aquaporin-4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) antibodies. OBJECTIVE: We aimed to investigate whether double seronegative NMOSD (DN-NMOSD) and NMOSD with AQP4 antibody (AQP4-NMOSD) share the same pathophysiological basis, astrocytopathy, by measurement of cerebrospinal fluid (CSF) glial fibrillary acidic protein (GFAP) levels as a marker of astrocyte damage. METHODS: Seventeen participants who (1) satisfied the 2015 diagnostic criteria for NMOSD, and (2) tested negative for AQP4 and MOG antibodies confirmed with repeated cell-based assays, and (3) had available CSF samples obtained at the point of clinical attacks, were enrolled from 4 medical centers (South Korea, Germany, Thailand, and Denmark). Thirty age-matched participants with AQP4-NMOSD, 17 participants with MOG antibody associated disease (MOGAD), and 15 participants with other neurological disorders (OND) were included as controls. The concentration of CSF GFAP was measured using enzyme-linked immunosorbent assay. RESULTS: CSF GFAP levels in the DN-NMOSD group were significantly lower than those in the AQP4-NMOSD group (median: 0.49 versus 102.9 ng/mL; p < 0.001), but similar to those in the OND (0.25 ng/mL) and MOGAD (0.39 ng/mL) control groups. The majority (90% (27/30)) of participants in the AQP4-NMOSD group showed significantly higher CSF GFAP levels than the highest level measured in the OND group, while no participant in the DN-NMOSD and MOGAD groups did. CONCLUSIONS: These results suggest that DN-NMOSD has a different underlying pathogenesis other than astrocytopathy, distinct from AQP4-NMOSD.

Astrocytic outer retinal layer thinning is not a feature in AQP4-IgG seropositive neuromyelitis optica spectrum disorders.

BACKGROUND: Patients with anti-aquaporin-4 antibody seropositive (AQP4-IgG+) neuromyelitis optica spectrum disorders (NMOSDs) frequently suffer from optic neuritis (ON) leading to severe retinal neuroaxonal damage. Further, the relationship of this retinal damage to a primary astrocytopathy in NMOSD is uncertain. Primary astrocytopathy has been suggested to cause ON-independent retinal damage and contribute to changes particularly in the outer plexiform layer (OPL) and outer nuclear layer (ONL), as reported in some earlier studies. However, these were limited in their sample size and contradictory as to the localisation. This study assesses outer retinal layer changes using optical coherence tomography (OCT) in a multicentre cross-sectional cohort. METHOD: 197 patients who were AQP4-IgG+ and 32 myelin-oligodendrocyte-glycoprotein antibody seropositive (MOG-IgG+) patients were enrolled in this study along with 75 healthy controls. Participants underwent neurological examination and OCT with central postprocessing conducted at a single site. RESULTS: No significant thinning of OPL (25.02±2.03 µm) or ONL (61.63±7.04 µm) were observed in patients who were AQP4-IgG+ compared with patients who were MOG-IgG+ with comparable neuroaxonal damage (OPL: 25.10±2.00 µm; ONL: 64.71±7.87 µm) or healthy controls (OPL: 24.58±1.64 µm; ONL: 63.59±5.78 µm). Eyes of patients who were AQP4-IgG+ (19.84±5.09 µm, p=0.027) and MOG-IgG+ (19.82±4.78 µm, p=0.004) with a history of ON showed parafoveal OPL thinning compared with healthy controls (20.99±5.14 µm); this was not observed elsewhere. CONCLUSION: The results suggest that outer retinal layer loss is not a consistent component of retinal astrocytic damage in AQP4-IgG+ NMOSD. Longitudinal studies are necessary to determine if OPL and ONL are damaged in late disease due to retrograde trans-synaptic axonal degeneration and whether outer retinal dysfunction occurs despite any measurable structural correlates.

Reappraisal of CSF-specific oligoclonal bands in Asia.

The prevalence of cerebrospinal fluid-specific oligoclonal bands (CSF-OCBs) was reported to be low in Asian people with multiple sclerosis (pwMS) compared to that in Western pwMS. It is yet to be determined whether it is a genuine feature of Asian pwMS or a misapprehension owing to past mis-classification of MS-mimicking diseases as MS. We aimed to reappraise the prevalence of CSF-OCBs in Korean pwMS after carefully excluding other central nervous system-inflammatory demyelinating diseases since 2017. Among 88 subjects, 78 (88.6%) were positive for CSF-OCBs, which suggests the prevalence of CSF-OCBs is not different between Korean and Western pwMS.

Absence of attack-independent neuroaxonal injury in MOG antibody-associated disease: Longitudinal assessment of serum neurofilament light chain.

To evaluate the occurrence of attack-independent neuroaxonal and astrocytic damage in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), serum neurofilament light chain (sNfL) and serum glial fibrillary acidic protein (sGFAP) levels were longitudinally measured in 102 sera using a single-molecule array assay. Sera from 15 adults with relapsing MOGAD with available longitudinal samples for the median 24-month follow-up and 26 age-/sex-matched healthy controls were analyzed. sNfL levels were significantly elevated in all clinical attacks, where the levels decreased below or close to cut-off value within 6 months after attacks. sNfL levels were consistently low during inter-attack periods. In contrast, sGFAP levels did not increase in most clinical attacks and remained low during follow-up. Significant neuroaxonal damage was observed at clinical attacks, while attack-independent neuroaxonal and astrocytic injury was absent in MOGAD.

Brighter spotty lesions on spinal MRI help differentiate AQP4 antibody-positive NMOSD from MOGAD.

In a large acute myelitis cohort, we aimed to determine whether brighter spotty lesions (BSLs)-using the refined terminology-on spinal magnetic resonance imaging (MRI) help distinguish aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (AQP4-NMOSD) from myelin oligodendrocyte glycoprotein antibody disease (MOGAD). An experienced neuro-radiologist and two neurologists independently analyzed 133 spinal MRI scans (65 from MOGAD and 68 from AQP4-NMOSD) acquired within 1 month of attacks. BSLs were observed in 18 of 61 (30%) participants with AQP4-NMOSD, while none of 49 participants with MOGAD showed BSL (p < 0.001). BSL during the acute phase would be useful to differentiate AQP4-NMOSD from MOGAD.

So You Want to Image Myelin Using MRI: An Overview and Practical Guide for Myelin Water Imaging.

Myelin water imaging (MWI) is an MRI imaging biomarker for myelin. This method can generate an in vivo whole-brain myelin water fraction map in approximately 10 minutes. It has been applied in various applications including neurodegenerative disease, neurodevelopmental, and neuroplasticity studies. In this review we start with a brief introduction of myelin biology and discuss the contributions of myelin in conventional MRI contrasts. Then the MRI properties of myelin water and four different MWI methods, which are categorized as T2 -, T2 *-, T1 -, and steady-state-based MWI, are summarized. After that, we cover more practical issues such as availability, interpretation, and validation of these methods. To illustrate the utility of MWI as a clinical research tool, MWI studies for two diseases, multiple sclerosis and neuromyelitis optica, are introduced. Additional topics about imaging myelin in gray matter and non-MWI methods for myelin imaging are also included. Although technical and physiological limitations exist, MWI is a potent surrogate biomarker of myelin that carries valuable and useful information of myelin. Evidence Level: 5 Technical Efficacy: 1 J. MAGN. RESON. IMAGING 2021;53:360-373.

Recurrence of clinical events at the same anatomical location in patients with MOG antibody-associated disease.

OBJECTIVES: Likelihood of clinical events occurring within the same anatomical location in patients with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) was retrospectively investigated. METHODS: A total of 236 clinical events in 90 patients with MOGAD from nine referral hospitals were analyzed via logistic regression, and odds ratios (ORs) were calculated. Anatomical lesion location was divided into four groups; optic nerve, spinal cord, cerebral hemisphere, and brainstem/cerebellum. RESULTS: At all locations, there was an increased likelihood of a second attack occurring at the same location as the initial event (cerebral hemisphere OR = 22.14, brainstem/cerebellum OR = 18.4, spinal cord OR = 9.1, and optic nerve OR = 7.8). There was an increased likelihood of a third attack occurring at the same location as the initial event in the optic nerve (OR = 14.9), cerebral hemisphere (OR = 11.7), and spinal cord (OR = 6.7). There were positive trends toward a third clinical event occurring at the same location as the first and/or second events if the event was in the optic nerve (OR = 13.5), cerebral hemisphere (OR = 6.9), or spinal cord (OR = 5.7). CONCLUSIONS: The current study suggests that clinical relapses of MOGAD during early stage tend to recur at the same anatomical locations in the central nervous system.