Zalewski, Nicholas L.

Background: Radiologically Isolated Syndrome (RIS) is defined as incidentally found MRI abnormalities that are radiographically indistinguishable from multiple sclerosis (MS) and is considered a presymptomatic disease state of MS. Age <37 years, infratentorial or spinal cord lesions, gadolinium-enhancing lesions on index imaging, and positive cerebrospinal fluid oligoclonal bands have been identified as risk factors for conversion to MS. There are no existing guidelines regarding the role of disease-modifying therapy (DMT) in RIS patients. Objective: The objective of this study was to critically assess the current evidence regarding the impact of initiating DMT for patients with RIS on the time to first clinical attack of MS. Methods: The objective was addressed through the development of a structured critically appraised topic. This included a clinical scenario with a clinical question, literature search strategy, critical appraisal, results, evidence summary, commentary, and bottom-line conclusions. Participants included consultant and resident neurologists, medical librarian, and content experts in the field of neuroimmunology. Results: A multicenter, prospective, randomized, double-blind, placebo-controlled trial was chosen for critical appraisal. This trial examined the impact of treatment with dimethyl fumarate (DMF) versus placebo on the risk of conversion from RIS to MS over a 96-week study period. Patients in the DMF arm were found to have an 82% reduction in risk of clinical attack. DMF patients also had a smaller number of new/newly enlarging T2 hyperintense lesions compared with placebo. No subgroup analyses were performed to elucidate risk factors for conversion. Conclusions: While initiation of DMT in RIS does appear to reduce the time to first clinical attack of MS, the risk factors that should prompt initiation of DMT in this patient population require further study.

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.