Pittock, S J

Background Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) and multiple sclerosis (MS) have both overlapping and distinct MRI lesion features, which vary with imaging timing. This study identified distinguishing MRI characteristics using paired MRIs at clinical attack and remission. Methods We retrospectively identified Mayo Clinic patients with MOGAD and MS that: (1) fulfilled respective diagnostic criteria; (2) had paired attack (≤30 days) and remission MRI scans (≥12 months) without interval attacks. MRIs were compared between groups for key features. Results We included 43 patients with MOGAD (median age 31 years (range, 3–67); 63% female) and 49 patients with MS (median age 39 years (range, 17–65); 65% female). Resolution of at least one T2-lesion differentiated MOGAD from MS (sensitivity, (95% CI 77% to 100%), specificity, (95% CI 86% to 99%); Youden’s index (YI)=0.90). Resolution of at least two T2-lesions indicated MOGAD (sensitivity 62% (95% CI 41% to 79%); specificity, 100% (95% CI 94% to 100%); YI=0.62). MOGAD patients were more likely to have normal MRI scans at follow-up compared with MS (brain 14/44 (32%) vs 0/60 (0%), p<0.001; spine 21/27 (78%) vs 7/36 (19%), p<0.001). In addition, the presence of T1-hypointense, ovoid periventricular T2, and enhancing lesions were more common in MS versus MOGAD at attack and remission and in the spine, longitudinally extensive T2 lesions were more common in MOGAD attacks (8/27 (30%)). Conclusion Paired MRI at attack and remission revealed distinctive characteristics of MOGAD and MS, with greater diagnostic value at remission driven by the discriminating power of T2-lesion resolution. In MOGAD patients with initial parenchymal involvement, a 1-year follow-up MRI may aid diagnosis and serve as a new baseline.

Abstract Anti-IgLON5 disease is an autoimmune encephalitis that presents with a heterogenous clinical phenotype, including sleep disorders, movement abnormalities and bulbar involvement. It is characterized by autoantibodies against IgLON5, 85% association with HLA-DQB1*05:∼ and a brainstem-dominant tauopathy. Cellular and murine models report pathogenic effects of the autoantibodies, and neurodegenerative factors suggest progressive atrophy as a common sequela. However, evidence from in vivo patient data and long-term follow-up is limited, and the degree of progression remains elusive. In this multicentre study, clinical and brain MRI data were collected from 127 patients across 12 countries to investigate the relationships between clinical presentations and the development of distinct brain atrophy patterns. Our data show that most patients develop a complex multisystem phenotype as the disease progresses; however, neuromuscular manifestations rarely emerge at later disease stages. By comparison to healthy controls, this disease presents with severe substructure-specific atrophy, especially affecting the hypothalamus, brainstem, accumbens and basal ganglia, which, in age-independent analyses, show significant ventricular enlargement and also suggest progression of brainstem atrophy over the disease course. Moreover, the focality of atrophy was functionally linked to specific symptoms, with more severe involvement of the basal ganglia in patients with movement disorders, and greater atrophy in the hippocampus and thalamus in patients with cognitive impairment. Taken together, our results provide evidence of distinct atrophy patterns in anti-IgLON5 disease, which closely mirror sites of pathophysiologic processes, including autoantibody binding and tau deposition. Our data emphasize the brainstem as the pathophysiological hub of the disease and provide normative data for the incorporation of atrophy measurements into routine clinical assessments and future treatment studies to monitor disease trajectory and evaluate future treatment strategies.

This case series examines long-term outcomes for 2 aquaporin-4-IgG (AQP4-IgG)–positive patients with neuromyelitis optica spectrum disorder (NMOSD) who underwent autologous hematopoietic stem cell transplantation with a nonmyeloablative conditioning regimen and rituximab.

Background Falls in people with multiple sclerosis (pwMS) lead to morbidity and expense. Objective Identify clinical metrics associated with falls. Methods Eighty-six pwMS completed fall surveys, timed 25-foot walk (T25FW), and motion analysis with Clario Opal devices. Logistic regression models were created. Results Median age was 54.5 years (range 21–73), 62% (53) were female. The cohort included 58% with relapsing (50) and 42% with progressive MS (36). Those who reported falling in the last year were older (median age 58 vs 52.5, p = .03) and had a higher Patient Determined Disease Step (PDDS) score (median 3 vs 1, p < .0001). Falls were associated with worse balance metrics including sway area (median 2.3 degrees 2 vs 1.2, p = .01), jerk (median 3.3 m 2 /s 5 vs 1.6, p = .005), and slower T25FW (median 11.5 s vs 8; p < .0001). A multivariable regression model based on gait aid use and T25FW time >10.8 s (c = 0.80) was derived. Having both features portended a probability of falling of 0.97, while having neither, a probability of 0.26. Conclusions Falls in pwMS are more frequent in patients who are older, have higher PDDS, slower walking, and worse balance. Gait aid use and T25FW >10.8 s were strongly associated with falls in the past year.

ABSTRACTCavin‐4 was identified as a potential autoantigen for immune‐mediated rippling muscle disease (iRMD). To validate this, we developed and tested various immunoassays, including a cell‐based assay (CBA), cavin‐4 recombinant protein ELISA, and multi‐peptide ELISA. Among 19 iRMD patients, all exhibited muscle rippling, and 13 had percussion‐induced mounding. All immunoassays demonstrated clinical and analytical specificities greater than 95%. The protein ELISA had the highest sensitivity (94.7%) and specificity (99.9%), outperforming CBA (sensitivity 89.5%, specificity 99.6%) and the multi‐peptide ELISA (sensitivity 79.0%, specificity 97.2%). Our results suggest that the cavin‐4 protein ELISA is a promising tool for high‐throughput clinical testing in iRMD.

AbstractCases of myelin oligodendrocyte glycoprotein (MOG) antibody‐associated disease (MOGAD) co‐occurring with neoplasms have been reported. In this international, retrospective cohort study in South Korea and the USA, 16 of 445 (3.6%) patients with MOGAD had concurrent neoplasm within 2 years of MOGAD onset, resulting in a standardized incidence ratio for neoplasm of 3.10 (95% confidence interval [CI], 1.77–4.81; P < 0.001) when compared to the age‐ and country‐adjusted incidence of neoplasm in the general population. However, none of the nine tumor tissues obtained demonstrated MOG immunostaining. The slightly increased frequency without immunohistopathological evidence suggest with true paraneoplastic MOGAD is extremely rare.

Abstract Objective To assess the real‐world performance of a live (LCBA) versus a fixed (FCBA) cell‐based assay for the detection of serum antibodies directed against myelin oligodendrocyte glycoprotein (MOG‐IgG) and aquaporin‐4 (AQP4‐IgG). Methods This was a retrospective study of patients evaluated at a single tertiary academic referral center, with serum testing performed clinically for AQP4‐IgG and/or MOG‐IgG by FCBA and LCBA on the same day. Additionally, frozen banked sera from the same day for patients tested only by one assay were retrieved and tested by the other assay. FCBA was performed by the Johns Hopkins Immunology Laboratory using Euroimmun kits with detection by indirect immunofluorescence (FCBA‐IF), whereas LCBA was performed by the Mayo Clinic Neuroimmunology Laboratory with detection by flow cytometry (LCBA‐FACS). Results Of 594 specimens with paired MOG‐IgG testing, 500 were negative by both assays, 33 were positive by both assays, 56 were positive exclusively by LCBA‐FACS, and 5 were only positive by FCBA‐IF. Overall, MOG‐IgG LCBA‐FACS exhibited 95.1% sensitivity and 97.7% specificity, whereas MOG‐IgG FCBA‐IF had 45.7% sensitivity and 99.8% specificity. Of 577 specimens with paired AQP4‐IgG testing, 503 were negative by both assays, 51 were positive by both assays, 21 were positive exclusively by LCBA‐FACS, and 2 were only positive by FCBA‐IF. Overall, AQP4‐IgG LCBA‐FACS exhibited 97.3% sensitivity and 100% specificity, whereas AQP4‐IgG FCBA‐IF had 71.6% sensitivity and 100% specificity. Interpretation LCBA‐FACS for both MOG‐IgG and AQP4‐IgG had markedly better sensitivity than FCBA‐IF, with similar specificity. The use of FCBA‐IF may result in underrecognition of both MOG antibody‐associated disease (MOGAD) and AQP4‐IgG seropositive neuromyelitis optica spectrum disorder (NMOSD).

AbstractDefining the CSF cytokine/chemokine and injury biomarker signature of glial fibrillary acidic protein (GFAP) autoimmunity can inform immunopathogenesis. CSF GFAP‐IgG‐positive samples (N = 98) were tested for 17 cytokines/chemokines, neurofilament light chain (NfL), and GFAP (ELLA, Bio‐Techne). Controls included non‐inflammatory (N = 42), AQP4‐IgG‐positive (N = 83), CNS infections (N = 13), and neurosarcoidosis (N = 32). IL5, IL6, IL10, IL8/CXCL8, CXCL9, CXCL10, CXCL13, BAFF, GM‐CSF, IFN‐gamma, and TNF‐alpha concentrations were higher compared to non‐inflammatory controls (P < 0.01). GFAP concentrations were similar to those of AQP4‐IgG‐positive patients; NfL was higher (P < 0.001) and correlated with MRI changes and outcomes. CSF cytokine/chemokine findings in GFAP autoimmunity correlate with histopathology; GFAP and NfL hold promise as disease biomarkers.

Background Data regarding long-term recovery from autoimmune encephalitis (AE) remain limited. Methods This retrospective observational study investigated outcomes in 182 patients who met the 2016 criteria for definite AE. Recovery data were available in 172 patients. Follow-up data at ≥24 months post-attack were available for 119. Recovery trajectory, residual symptoms, outcome predictors and causes of post-AE death were assessed. Results Of 172 patients, 138 (80%) achieved good recovery (modified Rankin Scale (mRS) ≤2) with a median recovery time of 4 months (95% CI: 2 to 6 months). Recovery varied by associated neural antibody, with the best recovery observed in leucine-rich glioma-inactivated 1 (97% good recovery, median recovery time 0 (0 to 2) months). Paraneoplastic AE (p=0.007), severe attacks (eg, mRS ≥4 at attack, p=0.007) and cerebrospinal fluid pleocytosis (p=0.005) were associated with a lower likelihood of good recovery, while seizure presentation (p=0.026) was associated with better recovery. Despite good recovery, several residual symptoms persisted ≥24 months post-AE, including cognitive deficits (53%), seizures (26%), depression (23%), sleep disorders (25%), brainstem/cerebellar symptoms (13%), other movement disorders (14%) and autonomic symptoms (12%). Predictors of long-term sequelae included disabling cognitive deficit at onset and delayed immunotherapy for post AE-dementia, and medial temporal atrophy as well as escalation to cyclophosphamide therapy for both drug-resistant epilepsy and chronic depression. Of 182 patients, 20 (11%) died; the most common cause of death was progression of AE (6/20 (30%)). Conclusion While the majority of patients achieved functional independence after AE, several residual symptoms persisted. Several clinical and paraclinical features were associated with long-term sequelae.