B cell depletion therapy does not resolve chronic active multiple sclerosis lesions.

BACKGROUND: Chronic active lesions (CAL) in multiple sclerosis (MS) have been observed even in patients taking high-efficacy disease-modifying therapy, including B-cell depletion. Given that CAL are a major determinant of clinical progression, including progression independent of relapse activity (PIRA), understanding the predicted activity and real-world effects of targeting specific lymphocyte populations is critical for designing next-generation treatments to mitigate chronic inflammation in MS. METHODS: We analyzed published lymphocyte single-cell transcriptomes from MS lesions and bioinformatically predicted the effects of depleting lymphocyte subpopulations (including CD20 B-cells) from CAL via gene-regulatory-network machine-learning analysis. Motivated by the results, we performed in vivo MRI assessment of PRL changes in 72 adults with MS, 46 treated with anti-CD20 antibodies and 26 untreated, over ∼2 years. FINDINGS: Although only 4.3% of lymphocytes in CAL were CD20 B-cells, their depletion is predicted to affect microglial genes involved in iron/heme metabolism, hypoxia, and antigen presentation. In vivo, tracking 202 PRL (150 treated) and 175 non-PRL (124 treated), none of the treated paramagnetic rims disappeared at follow-up, nor was there a treatment effect on PRL for lesion volume, magnetic susceptibility, or T1 time. PIRA occurred in 20% of treated patients, more frequently in those with ≥4 PRL (p = 0.027). INTERPRETATION: Despite predicted effects on microglia-mediated inflammatory networks in CAL and iron metabolism, anti-CD20 therapies do not fully resolve PRL after 2-year MRI follow up. Limited tissue turnover of B-cells, inefficient passage of anti-CD20 antibodies across the blood-brain-barrier, and a paucity of B-cells in CAL could explain our findings. FUNDING: Intramural Research Program of NINDS, NIH; NINDS grants R01NS082347 and R01NS082347; Dr. Miriam and Sheldon G. Adelson Medical Research Foundation; Cariplo Foundation (grant #1677), FRRB Early Career Award (grant #1750327); Fund for Scientific Research (FNRS).

Epidemiology, clinical presentation, treatment, and outcome of neurosarcoidosis: A mono-centric retrospective study and literature review.

Introduction: Neurosarcoidosis is a rare granulomatous disorder, and treatment guidelines are mainly based on retrospective studies. Materials and methods: This retrospective study was performed to provide a detailed description of the clinical characteristics and treatment outcomes of patients with neurosarcoidosis followed at Cliniques Universitaires Saint Luc in Belgium. The second objective of our study was to perform a comparative literature review of neurosarcoidosis, with a focus on treatment outcomes with the use of TNF-α antagonist. Results: Among 180 patients with sarcoidosis followed in our hospital, 22 patients with neurosarcoidosis were included in the final analysis. Our literature research identified 776 articles of which 35 articles met our inclusion criteria, including 1,793 patients diagnosed with neurosarcoidosis. In our cohort, the majority of patients (86%) were diagnosed with systemic sarcoidosis which was similar to that reported in the literature (83%). Serum CRP and calcemia were elevated only in 33 and 18% of patients, respectively. Serum lysozyme and angiotensin-converting enzyme were elevated in 79 and 16% of patients, respectively. Lumbar puncture and CSF fluid analysis were performed in 15/22 patients and were abnormal in all patients. Brain MRI was performed in 21/22 patients and showed abnormalities in 16 patients consisting of parenchymal lesions in 63%, hypothalamic-pituitary axis lesions in 38%, and meningeal enhancement in 31%. In both cohort patients, methotrexate was the most frequently used treatment (>45% of cases) with a favorable outcome in an average of 50% of patients. A TNF-α antagonist was administered in 9% of patients in our cohort and in 27% of patients in the literature review. The proportion of favorable outcomes in literature research was significantly higher in patients treated with TNF-α antagonists compared to methotrexate (p < 0.0001), mycophenolate mofetil (p < 0.0001), or azathioprine (p < 0.0001). Conclusion: The results of our cohort and literature review confirm that neurosarcoidosis occurred most frequently in the context of systemic sarcoidosis. Methotrexate is the most frequent second-line therapy. The effectiveness of therapy with TNF-α antagonists is well-demonstrated and associated with a better outcome. Their earlier use during the disease course among aggressive and/or refractory neurosarcoidosis should be considered.

Immune-mediated neurological syndromes in SARS-CoV-2-infected patients.

BACKGROUND: Evidence of immune-mediated neurological syndromes associated with the severe acute respiratory syndrome coronavirus (SARS-CoV-2) infection is limited. We therefore investigated clinical, serological and CSF features of coronavirus disease 2019 (COVID-19) patients with neurological manifestations. METHODS: Consecutive COVID-19 patients with neurological manifestations other than isolated anosmia and/or non-severe headache, and with no previous neurological or psychiatric disorders were prospectively included. Neurological examination was performed in all patients and lumbar puncture with CSF examination was performed when not contraindicated. Serum anti-gangliosides antibodies were tested when clinically indicated. RESULTS: Of the 349 COVID-19 admitted to our center between March 23rd and April 24th 2020, 15 patients (4.3%) had neurological manifestations and fulfilled the study inclusion/exclusion criteria. CSF examination was available in 13 patients and showed lymphocytic pleocytosis in 2 patients: 1 with anti-contactin-associated protein 2 (anti-Caspr2) antibody encephalitis and 1 with meningo-polyradiculitis. Increased serum titer of anti-GD1b antibodies was found in three patients and was associated with variable clinical presentations, including cranial neuropathy with meningo-polyradiculitis, brainstem encephalitis and delirium. CSF PCR for SARS-CoV-2 was negative in all patients. CONCLUSIONS: In SARS-Cov-2 infected patients with neurological manifestations, CSF pleocytosis is associated with para- or post-infectious encephalitis and polyradiculitis. Anti-GD1b and anti-Caspr2 autoantibodies can be identified in certain cases, raising the question of SARS-CoV-2-induced secondary autoimmunity.

Acute Susac Syndrome in a Recent User of Adulterated Cocaine: Levamisole as a Triggering Factor?

Susac syndrome (SS) is a central nervous system vasculitis characterized by the clinical triad of encephalopathy, sensorineural hearing loss, and visual disturbance caused by branch retinal artery occlusion. It is considered as an inflammatory disorder, and an autoimmune etiology is suggested. A 29-year-old man with a history of recent cocaine abuse developed the clinical features of SS. Toxicological analysis including hair testing revealed that cocaine had been adulterated with levamisole. After an initial clinical improvement following corticosteroid therapy, the introduction of mycophenolate mofetil was justified a few weeks later by the progression (or relapse) of the retinal injury, followed by complete recovery. The presence of levamisole has been documented in patients with multifocal inflammatory leukoencephalopathy (MIL). Further investigations are needed to determine if levamisole as an adulterant of cocaine could also play a role in the development of rapidly progressive leukoencephalopathy in young men, with Susac or Susac-like syndromes as possible variants of MIL.