Abstract Faciobrachial dystonic seizures (FBDS), paroxysmal dizziness spells, and thermal sensory attacks are highly frequent and stereotypic phenomena experienced in leucine‐rich glioma inactivated 1 (LGI1)‐antibody encephalitis. This study aims to describe the electrophysiologic mechanism underlying these pathognomonic symptoms. LGI1‐antibody encephalitis patients with active symptoms were enrolled from two separate centers in South Korea and the United States. Patients were evaluated with simultaneous magnetoencephalography (306 channels) and electroencephalography. Regional alterations in neuronal excitability represented by interictal epileptiform discharges were present in the faciobrachial area of the motor cortex, insula, and somatosensory cortex, somatotopically aligned with each of the ictal semiologies observed in patients. FBDS and other LGI1‐antibody encephalitis‐specific spells localized to cortical regions neuroanatomically corresponding to ictal semiologies: the faciobrachial homunculus (FBDS), insular cortex (paroxysmal dizziness spells), and somatosensory cortex (thermal sensory attacks). Our findings support the ictal hypothesis underlying these unique phenomena.
Enterovirus Encephalitis in People With Multiple Sclerosis on Ocrelizumab
INNV-52. Mixed histiocytosis of the thoracic dura: a rare presentation of Mixed Erdheim-Chester Disease and Rosai-Dorfman Disease mimicking IgG4-Related Disease
Abstract BACKGROUND Mixed histiocytic neoplasms with overlapping features of Erdheim-Chester Disease (ECD) and Rosai-Dorfman Disease (RDD) are extremely rare and diagnosis may be delayed due to lack of awareness and complex histology features. METHODS We report a case of mixed ECD/RDD misdiagnosed as IgG4-related disease and review the literature. RESULTS A 50-year-old man presented for evaluation of spastic paraparesis in the context of a thoracic dural lesion. Two years prior he developed an inflammatory monoarthritis concerning for rheumatoid arthritis unresponsive to methotrexate. Six months prior he developed leg spasms, gait spasticity, and urinary incontinence. MRI demonstrated a T2 hypointense enhancing epidural mass with spinal cord compression. Epidural biopsy showed fibrosis and non-specific inflammation. Given elevated serum IgG4 (170 mg/dL) and clinical findings, he was diagnosed with IgG4-related disease. He received high dose prednisone and etanercept without radiographic or clinical improvement. He then presented to our institution. Given high concern for RDD, he underwent FDG-PET CT which demonstrated an infiltrative process and FDG avid regions in the upper thoracic spinal cord, paranasal sinus, renal hilum, perivascular abdominal vessels, testicle, and multiple joint effusions. Biopsy of left testicle demonstrated CD163-positive histiocytes which coexpressed S100, cyclin D1, and OCT2, consistent with RDD. Biopsy of the left shoulder synovium demonstrated an atypical CD163-positive histiocytic infiltrate expressing Factor XIIIa, cyclin D1 and S100 (partial), and appeared negative for OCT2, consistent with ECD. The atypical histiocytes in both biopsies were negative for CD1a and BRAF V600E by immunohistochemistry. Genomic sequencing of the testicular tissue demonstrated a MAP2K1 (Q56P) alteration. He was treated with radiation therapy targeting the dural lesion with temporarily worsening symptoms improved with steroids and started on cobimetinib. DISCUSSION This case expands on the phenotypic description of mixed ECD/RDD. Histiocytic neoplasms should be considered in the differential diagnosis of dural based lesions.
Tremor and disability outcomes following deep brain stimulation for multiple sclerosis-associated tremor
Background: Tremor in multiple sclerosis (MS) is often refractory to medications. Deep brain stimulation (DBS) may help, but possible side effects and disease exacerbation limit its use. Objectives: Evaluate outcomes of DBS for MS-associated tremor. Methods: Retrospective review of 18 patients with MS-associated tremor who underwent DBS, analyzing Expanded Disability Status Scale (EDSS) and Fahn–Tolosa–Marin (FTM) tremor scores. Results: Median age at surgery was 49.5 years (range, 28–75), with postoperative follow-up 2.5 years (range, 0–22). No relapses (0/18) or new lesions (0/8) occurred postoperatively. All had ventral intermediate nucleus leads; other targets were not used in programming. EDSS remained stable (median 6 to 6.25; p = 0.2). FTM scores improved (median 14.5 to 10, p = 0.008). Patients with EDSS 3.5–6 had variable outcomes ( p = 0.02). Conclusions: DBS is a potential treatment for severe MS tremor and did not provoke relapse. Targeting VIM alone may optimize tremor control and maintain magnetic resonance imaging (MRI) access.
Application of the ADEM definition to cerebral attacks of MOG antibody-associated disease
Background: Acute disseminated encephalomyelitis (ADEM) is a demyelinating syndrome observed in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) but there are limited data on application of this definition to its cerebral attacks or in adults with this disease. Methods: We analyzed patients from the Mayo Clinic MOGAD cohort ( n = 263) with cerebral attacks. We assessed whether children (<18 years-old) and adults (⩾18 years-old) fulfilled the 2013 ADEM definition. Results: We identified 89 patients (children, 34; adults, 55) and 55/89 (62%) were of female sex. Acute magnetic resonance imaging (MRI) abnormalities included: poorly demarcated T2 lesions (white matter, 85 (96%); deep gray matter, 41 (46%); T1-hypointense lesions (42 (47%)). Forty-two patients did not fulfill the ADEM definition due to: monofocal syndrome, 9; or no encephalopathy, 33. The remaining 47 patients (53%: children, 27/34 (79%); adults, 20/55 (36%)) fulfilled the ADEM definition, and 14 had preceding attacks, and 34 had subsequent attacks relative to ADEM episode. The features in children and adults with ADEM were broadly comparable. Conclusion: Applying the ADEM definition to MOGAD cerebral attacks highlighted that an update of the 2013 ADEM definition would be beneficial and could explicitly state its application to both adults and children and allow it to be applied to attacks at any time during the disease course.
Assessing fall risk in multiple sclerosis using patient-reported outcomes and wearable gait metrics
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.
Tremor and Disability Outcomes After Deep Brain Stimulation for Multiple Sclerosis-associated Tremor (P12-1.014)