Multiple sclerosis in Somali Americans: Nature or nurture?

BACKGROUND: Differences in the MS course between White and Black populations is well accepted. The existence of a large Somali immigrant population in Minnesota facilitates a study of MS characteristics in this immigrant native African population. The objective of this study was to compare Somali American (SA), African American (AA), and White American (WA) persons with MS (pwMS) regarding clinical features and disease modifying therapy (DMT) use. METHODS: This single center (Mayo Clinic) geographically-restricted retrospective cohort study (residing within 250 miles of Rochester, MN, USA) included participants seen before May 2023. Age at immigration to the USA; age at MS onset; DMT use/type; MS phase/phenotype; age at progressive MS (PMS) onset; and proportion with severe MS (expanded disability status scale-EDSS ≥6) were examined. RESULTS: 18 SApwMS, 92 AApwMS, and 94 WApwMS were included. Of the 15 SApwMS not born in USA, 3/15 immigrated pre-puberty, 3/15 peri­puberty, 8/15 post-puberty, and 1/15 at an unknown date. SApwMS were younger at MS onset (median years, interquartile range (IQR)=25, 22-33 vs. AApwMS: 31, 25-38; p = 0.049 vs. WApwMS: 35, 27-41; p = 0.022). DMT use frequencies were 13/19 SApwMS, 69/92 AApwMS, 80/94 WApwMS (p > 0.05). SApwMS were treated with DMT earlier than AApwMS (HR 2.16, p = 0.012) and WApwMS (HR 1.86, p = 0.041). SApwMS were less commonly treated with natalizumab (SApwMS 0 %, AApwMS 13 %, WApwMS 25 %; p = 0.035) and anti-CD20 therapies (SApwMS 23 %, AApwMS 23 %, WApwMS 48 %; p = 0.005). PMS occurred in 3/19 SApwMS, 28/92 AApwMS and 29/94 WApwMS (p > 0.05). Age of PMS onset in SApwMS (47 years, 34-57) was similar to WApwMS (47 years, 31-71; p > 0.05) but older than AApwMS (41 years, 18-7; p = 0.008). CONCLUSIONS: SApwMS that recently immigrated to the USA have similar disease course to WApwMS, and better than AApwMS from the same geographical region.

Cerebrospinal Fluid Cytokine and Chemokine Profiles in Central Nervous System Sarcoidosis: Diagnostic and Immunopathologic Insights.

OBJECTIVE: To evaluate the cerebrospinal fluid (CSF) cytokine/chemokine profile of central nervous system (CNS) neurosarcoidosis (NS), and its utility in differential diagnosis, treatment, and prognostication. METHODS: In this case-control study, we validated 17 cytokines/chemokines (interleukin [IL]-1-beta, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12p70, IL-13, IL-17A, BAFF, IL-8/CXCL8, CXCL9, CXCL10, CXCL13, GM-CSF, interferon-gamma, and tumor necrosis factor [TNF]-alpha) in a multiplexed automated immunoassay system (ELLA; Bio-Techne, Minneapolis, MN, USA), and assessed them in CSF and serum of symptomatic patients with probable or definite CNS NS (01/2011-02/2023) with gadolinium enhancement and/or CSF pleocytosis. Patients with multiple sclerosis, primary CNS lymphoma, aquaporin-4 immunoglobulin G positivity, non-inflammatory disorders, and healthy individuals were used as controls. RESULTS: A total of 32 NS patients (59% women; median age, 59 years [19-81]) were included; concurrent sera were available in 12. CSF controls consisted of 26 multiple sclerosis, 8 primary CNS lymphoma, 84 aquaporin-4 immunoglobulin G positive, and 34 patients with non-inflammatory disorders. Gadolinium enhancement was present in 31 of 32 NS patients, and CSF pleocytosis in 27 of 32 (84%). CSF IL-2, IL-6, IL-10, IL-13, BAFF, IL-8/CXCL8, CXCL9, CXCL10, CXCL13, GM-CSF, interferon-gamma, and TNF-alpha levels were significantly higher in NS patients compared with non-inflammatory controls (p ≤ 0.02); elevations were more common in CSF than serum. Concurrent elevation of IL-6, CXCL9, CXCL10, GM-CSF, interferon-gamma, and TNF-alpha was present in 18 of 32 NS patients, but only in 1 control. Elevated IL-6, IL-10, IL-13, CXCL9, CXL10, GM-CSF, and TNF-alpha associated with measures of disease activity. INTERPRETATION: NS CSF cytokine/chemokine profiles suggest T cell (mainly T helper cell type 1), macrophage, and B-cell involvement. These signatures aid in NS diagnosis, indicate disease activity, and suggest therapeutic avenues. ANN NEUROL 2024.

Diagnostic Utility of MOG Antibody Testing in Cerebrospinal Fluid.

OBJECTIVE: The aim of this study was to assess the diagnostic utility of cerebrospinal fluid (CSF) myelin oligodendrocyte glycoprotein antibodies (MOG-IgG) testing. METHODS: We retrospectively identified patients for CSF MOG-IgG testing from January 1, 1996, to May 1, 2023, at Mayo Clinic and other medical centers that sent CSF MOG-IgG for testing including: controls, 282; serum MOG-IgG positive MOG antibody-associated disease (MOGAD), 74; serum MOG-IgG negative high-risk phenotypes, 73; serum false positive MOG-IgG with alternative diagnoses, 18. A live cell-based assay assessed CSF MOG-IgG positivity (IgG-binding-index [IBI], ≥2.5) using multiple anti-human secondary antibodies and end-titers were calculated if sufficient sample volume. Correlation of CSF MOG-IgG IBI and titer was assessed. RESULTS: The pan-IgG Fc-specific secondary was optimal, yielding CSF MOG-IgG sensitivity of 90% and specificity of 98% (Youden's index 0.88). CSF MOG-IgG was positive in: 4/282 (1.4%) controls; 66/74 (89%) serum MOG-IgG positive MOGAD patients; and 9/73 (12%) serum MOG-IgG negative patients with high-risk phenotypes. Serum negative but CSF positive MOG-IgG accounted for 9/83 (11%) MOGAD patients, and all fulfilled 2023 MOGAD diagnostic criteria. Subgroup analysis of serum MOG-IgG low-positives revealed CSF MOG-IgG positivity more in MOGAD (13/16[81%]) than other diseases with false positive serum MOG-IgG (3/15[20%]) (p = 0.01). CSF MOG-IgG IBI and CSF MOG-IgG titer (both available in 29 samples) were correlated (Spearman's r = 0.64, p < 0.001). INTERPRETATION: CSF MOG-IgG testing has diagnostic utility in patients with a suspicious phenotype but negative serum MOG-IgG, and those with low positive serum MOG-IgG results and diagnostic uncertainty. These findings support a role for CSF MOG-IgG testing in the appropriate clinical setting. ANN NEUROL 2024;96:34-45.

Powassan Virus Encephalitis: A Tertiary Center Experience.

BACKGROUND: Powassan virus (POWV) is an emerging arthropod-borne flavivirus, transmitted by Ixodes spp. ticks, which has been associated with neuroinvasive disease and poor outcomes. METHODS: A retrospective study was conducted at Mayo Clinic from 2013 to 2022. We included clinical and epidemiologic data of probable and confirmed neuroinvasive POWV cases. RESULTS: Sixteen patients with neuroinvasive POWV were identified; their median age was 63.2 years, and 62.5% were male. Six patients presented with rhombencephalitis, 4 with isolated meningitis, 3 with meningoencephalitis, 2 with meningoencephalomyelitis, and 1 with opsoclonus myoclonus syndrome. A median time of 18 days was observed between symptom onset and diagnosis. Cerebrospinal fluid analysis showed lymphocytic pleocytosis with elevated protein and normal glucose in the majority of patients. Death occurred within 90 days in 3 patients (18.8%), and residual neurologic deficits were seen in 8 survivors (72.7%). CONCLUSIONS: To our knowledge, this is the largest case series of patients with neuroinvasive POWV infection. We highlight the importance of a high clinical suspicion among patients who live in or travel to high-risk areas during the spring to fall months. Our data show high morbidity and mortality rates among patients with neuroinvasive disease.

Mitochondrial Reactive Oxygen Species and Lytic Programmed Cell Death in Acute Inflammation.

Significance: Redox signaling through mitochondrial reactive oxygen species (mtROS) has a key role in several mechanisms of regulated cell death (RCD), necroptosis, ferroptosis, pyroptosis, and apoptosis, thereby decisively contributing to inflammatory disorders. The role of mtROS in apoptosis has been extensively addressed, but their involvement in necrotic-like RCD has just started being elucidated, providing novel insights into the pathophysiology of acute inflammation. Recent Advances: p53 together with mtROS drive necroptosis in acute inflammation through downregulation of sulfiredoxin and peroxiredoxin 3. Mitochondrial hydroorotate dehydrogenase is a key redox system in the regulation of ferroptosis. In addition, a noncanonical pathway, which generates mtROS through the Ragulator-Rag complex and acts via mTORC1 to promote gasdermin D oligomerization, triggers pyroptosis. Critical Issues: mtROS trigger positive feedback loops leading to lytic RCD in conjunction with the necrosome, the inflammasome, glutathione depletion, and glutathione peroxidase 4 deficiency. Future Directions: The precise mechanism of membrane rupture in ferroptosis and the contribution of mtROS to ferroptosis in inflammatory disorders are still unclear, which will need further research. Mitochondrial antioxidants may provide promising therapeutic approaches toward acute inflammatory disorders. However, establishing doses and windows of action will be required to optimize their therapeutic potential, and to avoid potential adverse side effects linked to the blockade of beneficial mtROS adaptive signaling. Antioxid. Redox Signal. 39, 708-727.

Neurologic Manifestations of Rheumatologic Disease.

OBJECTIVE: This article describes the neurologic manifestations of systemic rheumatologic disorders. LATEST DEVELOPMENTS: Although most have historically been classified as autoimmune disorders, rheumatologic diseases are increasingly conceptualized as distributed along a spectrum with various contributions of autoimmune (adaptive immune dysregulation) and autoinflammatory (innate immune dysregulation) mechanisms. Our evolving understanding of systemic immune-mediated disorders has been accompanied by an expansion in our differential diagnoses and therapeutic options. ESSENTIAL POINTS: Rheumatologic disease involves both autoimmune and autoinflammatory mechanisms. Neurologic symptoms can be the first manifestation of these disorders, and familiarity with the systemic manifestations of specific diseases is essential to establish the correct diagnosis. Conversely, knowledge of the neurologic syndromes that are most likely to be associated with specific systemic disorders can help narrow the differential and increase confidence when attributing a neuropsychiatric symptom to an underlying systemic disorder.

Improving Neurology Inpatient Fall Rate: Effect of a Collaborative Interdisciplinary Quality Improvement Initiative.

Objective: To reduce unwitnessed inpatient falls on the neurology services floor at an academic medical center by 20% over 15 months. Patients and Methods: A 9-item preintervention survey was administered to neurology nurses, resident physicians, and support staff. Based on survey data, interventions targeting fall prevention were implemented. Providers were educated during monthly in-person training sessions regarding the use of patient bed/chair alarms. Safety checklists were posted inside each patient's room reminding staff to ensure that bed/chair alarms were on, call lights and personal items were within reach, and patients' restroom needs were addressed. Preimplementation (January 1, 2020, to March 31, 2021) and postimplementation (April 1, 2021, to June 31, 2022) rates of falls in the neurology inpatient unit were recorded. Adult patients hospitalized in 4 other medical inpatient units not receiving the intervention served as a control group. Results: Rates of falls, unwitnessed falls, and falls with injury all decreased after intervention in the neurology unit, with rates of unwitnessed falls decreasing by 44% (2.74 unwitnessed falls per 1000 patient-days before intervention to 1.53 unwitnessed falls per 1000 patient-days after intervention; P=.04). Preintervention survey data revealed a need for education and reminders on inpatient fall prevention best practices given a lack of knowledge on how to operate fall prevention devices, driving the implemented intervention. All staff reported significant improvement in operating patient bed/chair alarms after intervention (P<.001). Conclusion: A collaborative, multidisciplinary approach focusing on provider fall prevention education and staff checklists is a potential technique to reduce neurology inpatient fall rates.

Characteristics of Progressive Multifocal Leukoencephalopathy Associated With Sarcoidosis Without Therapeutic Immune Suppression.

Importance: Progressive multifocal leukoencephalopathy can occur in the context of systemic sarcoidosis (S-PML) in the absence of therapeutic immune suppression and can initially be mistaken for neurosarcoidosis or other complications of sarcoidosis. Earlier recognition of S-PML could lead to more effective treatment of the disease. Objective: To describe characteristics of patients with S-PML. Design, Setting, and Participants: For this case series, records from 8 academic medical centers in the United States were reviewed from 2004 to 2022. A systematic review of literature from 1955 to 2022 yielded data for additional patients. Included were patients with S-PML who were not receiving therapeutic immune suppression. The median follow-up time for patients who survived the acute range of illness was 19 months (range, 2-99). Data were analyzed in February 2023. Exposures: Sarcoidosis without active therapeutic immune suppression. Main Outcomes and Measures: Clinical, laboratory, and radiographic features of patients with S-PML. Results: Twenty-one patients with S-PML not receiving therapeutic immune suppression were included in this study, and data for 37 patients were collected from literature review. The median age of the 21 study patients was 56 years (range, 33-72), 4 patients (19%) were female, and 17 (81%) were male. The median age of the literature review patients was 49 years (range, 21-74); 12 of 34 patients (33%) with reported sex were female, and 22 (67%) were male. Nine of 21 study patients (43%) and 18 of 31 literature review patients (58%) had simultaneous presentation of systemic sarcoidosis and PML. Six of 14 study patients (43%) and 11 of 19 literature review patients (58%) had a CD4+ T-cell count greater than 200/µL. In 2 study patients, a systemic flare of sarcoidosis closely preceded S-PML development. Ten of 17 study patients (59%) and 21 of 35 literature review patients (60%) died during the acute phase of illness. No meaningful predictive differences were found between patients who survived S-PML and those who did not. Conclusions and Relevance: In this case series, patients with sarcoidosis developed PML in the absence of therapeutic immune suppression, and peripheral blood proxies of immune function were often only mildly abnormal. Systemic sarcoidosis flares may rarely herald the onset of S-PML. Clinicians should consider PML in any patient with sarcoidosis and new white matter lesions on brain magnetic resonance imaging.

Population-Based Evaluation of Total Protein in Cerebrospinal Fluid.

OBJECTIVES: To present a normal range of cerebrospinal fluid (CSF) protein levels in a community-based population and to evaluate factors that contribute to CSF protein level variability. PATIENTS AND METHODS: Samples of CSF protein were obtained from participants aged 32 to 95 years who underwent lumbar puncture (LP) between November 1, 2007, and October 1, 2017, as part of the Mayo Clinic Study of Aging, a longitudinal, population-based study of residents of Olmsted County, Minnesota. RESULTS: A total of 633 participants (58.1% male; 99.1% White; mean ± SD age, 70.9±11.6 years) underwent LP with recorded CSF protein level. Mean ± SD CSF protein level was 52.2±18.4 mg/dL (to convert to mg/L, multiply by 10), with a 95% reference interval of 24.0 to 93.4 mg/dL (range, 14.0-148.0 mg/dL). Spinal stenosis and arterial hypertension were associated with higher CSF protein levels on univariable analysis (P<.001). Increasing age, male sex, and diabetes were all independently associated with higher CSF protein levels on multivariable analysis (P<.001). In the 66 participants with repeated LPs within 2.5 years, the coefficient of repeatability was 26.1 mg/dL. Eleven participants (16.7%) had a CSF protein level difference of 20 mg/dL or more between serial LPs, and 4 (6.1%) had a difference of 25 mg/dL or more. There was a trend toward greater CSF protein level variability in patients with spinal stenosis (P=.054). CONCLUSION: This large population-based study showed that CSF protein level can vary significantly among individuals. Elevated CSF protein level was independently associated with older age, male sex, and diabetes and is higher than listed in many laboratories. These findings emphasize the necessity of evidence-based reevaluation and standardization of CSF protein metrics.

Critical Role of the Sulfiredoxin-Peroxiredoxin IV Axis in Urethane-Induced Non-Small Cell Lung Cancer.

Non-small cell lung cancer (NSCLC), the most common type of lung cancer, etiologically associates with tobacco smoking which mechanistically contributes to oxidative stress to facilitate the occurrence of mutations, oncogenic transformation and aberrantly activated signaling pathways. Our previous reports suggested an essential role of Sulfiredoxin (Srx) in promoting the development of lung cancer in humans, and was causally related to Peroxiredoxin IV (Prx4), the major downstream substrate and mediator of Srx-enhanced signaling. To further explore the role of the Srx-Prx4 axis in de novo lung tumorigenesis, we established Prx4-/- and Srx-/-/Prx4-/- mice in pure FVB/N background. Together with wild-type litter mates, these mice were exposed to carcinogenic urethane and the development of lung tumorigenesis was evaluated. We found that disruption of the Srx-Prx4 axis, either through knockout of Srx/Prx4 alone or together, led to a reduced number and size of lung tumors in mice. Immunohistological studies found that loss of Srx/Prx4 led to reduced rate of cell proliferation and less intratumoral macrophage infiltration. Mechanistically, we found that exposure to urethane increased the levels of reactive oxygen species, activated the expression of and Prx4 in normal lung epithelial cells, while knockout of Prx4 inhibited urethane-induced cell transformation. Moreover, bioinformatics analysis found that the Srx-Prx4 axis is activated in many human cancers, and their increased expression is tightly correlated with poor prognosis in NSCLC patients.

Ischiofemoral impingement syndrome provoked by labor: An unusual case of complete sciatic mononeuropathy.

Peripheral neuropathies are a recognized complication of labor in the post-partum period. Herein, we describe an uncommon presentation of sciatic mononeuropathy due to ischiofemoral impingement during labor. A 29-year-old, gravida 4 para 2, female presented post-partum with acute left lower limb paresthesia and left foot drop, following spontaneous vaginal delivery of twins. Neurological examination demonstrated no activation of the left sciatic-innervated muscles and sensory loss in the same distribution. Electromyography (EMG) demonstrated an acute complete left sciatic mononeuropathy. MRI of the lumbosacral plexus and sciatic nerve showed a narrowed quadratus femoris space with mild edema of the muscle, consistent with ischiofemoral impingement syndrome. In addition, there was flattening of the sciatic nerve as it passed through the ischiofemoral space. She was treated conservatively, and at 7-month follow-up, there was marked improvement in muscle strength with ongoing sensory impairment. Repeat EMG demonstrated reinnervation in all sciatic-innervated muscles. This case highlights the risk of a sciatic mononeuropathy secondary to ischiofemoral impingement in the peripartum setting. Future studies are needed to determine if women with a narrow ischiofemoral space at baseline are at increased risk for peripheral nerve injury during labor.

Autoimmune Encephalitis Misdiagnosis in Adults.

Importance: Autoimmune encephalitis misdiagnosis can lead to harm. Objective: To determine the diseases misdiagnosed as autoimmune encephalitis and potential reasons for misdiagnosis. Design, Setting, and Participants: This retrospective multicenter study took place from January 1, 2014, to December 31, 2020, at autoimmune encephalitis subspecialty outpatient clinics including Mayo Clinic (n = 44), University of Oxford (n = 18), University of Texas Southwestern (n = 18), University of California, San Francisco (n = 17), University of Washington in St Louis (n = 6), and University of Utah (n = 4). Inclusion criteria were adults (age ≥18 years) with a prior autoimmune encephalitis diagnosis at a participating center or other medical facility and a subsequent alternative diagnosis at a participating center. A total of 393 patients were referred with an autoimmune encephalitis diagnosis, and of those, 286 patients with true autoimmune encephalitis were excluded. Main Outcomes and Measures: Data were collected on clinical features, investigations, fulfillment of autoimmune encephalitis criteria, alternative diagnoses, potential contributors to misdiagnosis, and immunotherapy adverse reactions. Results: A total of 107 patients were misdiagnosed with autoimmune encephalitis, and 77 (72%) did not fulfill diagnostic criteria for autoimmune encephalitis. The median (IQR) age was 48 (35.5-60.5) years and 65 (61%) were female. Correct diagnoses included functional neurologic disorder (27 [25%]), neurodegenerative disease (22 [20.5%]), primary psychiatric disease (19 [18%]), cognitive deficits from comorbidities (11 [10%]), cerebral neoplasm (10 [9.5%]), and other (18 [17%]). Onset was acute/subacute in 56 (52%) or insidious (>3 months) in 51 (48%). Magnetic resonance imaging of the brain was suggestive of encephalitis in 19 of 104 patients (18%) and cerebrospinal fluid (CSF) pleocytosis occurred in 16 of 84 patients (19%). Thyroid peroxidase antibodies were elevated in 24 of 62 patients (39%). Positive neural autoantibodies were more frequent in serum than CSF (48 of 105 [46%] vs 7 of 91 [8%]) and included 1 or more of GAD65 (n = 14), voltage-gated potassium channel complex (LGI1 and CASPR2 negative) (n = 10), N-methyl-d-aspartate receptor by cell-based assay only (n = 10; 6 negative in CSF), and other (n = 18). Adverse reactions from immunotherapies occurred in 17 of 84 patients (20%). Potential contributors to misdiagnosis included overinterpretation of positive serum antibodies (53 [50%]), misinterpretation of functional/psychiatric, or nonspecific cognitive dysfunction as encephalopathy (41 [38%]). Conclusions and Relevance: When evaluating for autoimmune encephalitis, a broad differential diagnosis should be considered and misdiagnosis occurs in many settings including at specialized centers. In this study, red flags suggesting alternative diagnoses included an insidious onset, positive nonspecific serum antibody, and failure to fulfill autoimmune encephalitis diagnostic criteria. Autoimmune encephalitis misdiagnosis leads to morbidity from unnecessary immunotherapies and delayed treatment of the correct diagnosis.