Real-world efficacy, roll-out and uptake of intramuscular tixagevimab/cilgavimab as COVID-19 pre-exposure prophylaxis in people with multiple sclerosis and neuroimmunological conditions during the COVID-19 pandemic.

Background: In Australia, tixagevimab/cilgavimab 150 mg/150 mg was a government-funded pre-exposure prophylaxis for COVID-19 people with multiple sclerosis (pwMS) and other neuroimmunological conditions (pwNIc) treated with anti-CD20 antibodies or sphingosine-1-phosphate receptor modulators were eligible. Objective: To analyse the roll-out, uptake and real-world efficacy of tixagevimab/cilgavimab in the prevention and severity of COVID-19. To assess compliance with uptake depending on the location of delivery. Methods: We undertook a single-centre study. 440 pwMS and pwNIc were eligible. Logistic regression was used to assess predictors of COVID-19 during follow-up and to assess predictors of uptake among those who consented. Results: Of the eligible pwMS and pwNIc in our service, 52.7% (233/440) requested a consultation and were included in this study. Consultation resulted in 71.7% of people (167/233) receiving the treatment. Of these, 94.0% (157/167) had received three or more COVID-19 vaccines. Among those who received a single dose of tixagevimab/cilgavimab, 19.16% (32/167) tested positive for COVID-19 during the observational window. The majority of these were on ocrelizumab (68.8% (22/32)). None of those with COVID-19 required hospitalisation or supplemental oxygen. There was no difference in odds of COVID-19 during the observation period between those who received and did not receive tixagevimab/cilgavimab (adjusted OR, aOR 2.16 (95% CI 0.82 to 6.85), p=0.43). Uptake of tixagevimab/cilgavimab was highest when offered at the hospital infusion centre (aOR 3.09 (95% CI 1.08 to 9.94) relative to referral to the local pharmacy, p=0.04). Conclusion: Tixagevimab/cilgavimab administration did not protect against subsequent COVID-19 in our cohort. Compliance with uptake was influenced by administration location.

Neutropaenia complications from Ocrelizumab and Rituximab treatment.

Ocrelizumab is an anti-CD20 monoclonal antibody (mAb) that has been shown in phase 3 clinical trials to reduce relapses and disease progression in multiple sclerosis (MS) patients. Prior to the approval of ocrelizumab, rituximab, a chimeric anti-CD20 mAb was used to treat MS. Rituximab is still used to treat MS in many countries outside of Australia and remains mainstay of treatment of many non-MS neuroimmunological and systemic inflammatory diseases. Rituximab is currently used in neuromyelitis optica spectrum disorder (NMOSD) and autoimmune encephalitis, in addition to its widespread usage in hematological malignancies and systemic inflammatory diseases. Ocrelizumab is currently approved in Australia for treatment of relapsing-remitting MS (RRMS). Neutropaenia is a rare complication of both ocrelizumab and rituximab treatment. This case series reports 12 patients who have experienced neutropaenia following ocrelizumab or rituximab treatment and aims to characterize the clinical parameters of neutropaenia experienced by these patients, including the severity and duration of neutropaenia, length of hospital admission, the types of subsequent infections experienced and types of treatment necessary before patients reached count recovery. The unpredictability of neutropaenia and potential for serious infections highlight the need for continued hematological monitoring for patients on B-cell depleting therapies and calls for careful patient counselling to provide guidance on whether to continue such therapies in patients who have experienced related neutropaenia.

Development and validation of a peripheral cell ratio and lactate score for differentiating status epilepticus from prolonged psychogenic nonepileptic seizures.

OBJECTIVE: Differentiating status epilepticus (SE) from prolonged psychogenic nonepileptic seizures (pPNES) can be difficult clinically. We aimed to define the utility of peripheral cell counts, cell ratios, and lactate levels in distinguishing SE from pPNES. METHODS: Retrospective two-center study investigating the sensitivity and specificity of acute (≤12 h of event offset) peripheral cell counts, cell ratios (neutrophil-lymphocyte ratio, neutrophil-monocyte ratio, monocyte-lymphocyte ratio, platelet-lymphocyte ratio, systemic immune-inflammatory index [SII], systemic inflammatory response index [SIRI]), and lactate levels in differentiating SE from pPNES. Patients were identified from two tertiary hospitals, with one forming the development cohort and the other the validation cohort. Using generalized additive models to generate biomarker vs time curves, optimal blood collection times were defined for set parameters. Three diagnostic scores combining neutrophil count, SII, or SIRI with lactate levels were developed and validated in separate cohorts. RESULTS: For the development cohort, 1262 seizure-like events were reviewed and 79 SE and 44 pPNES events were included. For the validation cohort, 241 events were reviewed and 20 SE and 11 pPNES events were included. Individually, the biomarkers generally had low sensitivity and reasonable specificity for differentiating SE from pPNES, with the neutrophil count, SIRI, and SII performing best with sensitivities of 0.65-0.84, specificities of 0.64-0.89, and ROC AUCs of 0.78-0.79. Lactate levels peaked at 60 min, while cell counts and ratios peaked after 240 min. Combining early peaking lactate levels and later peaking neutrophil count, SIRI or SII resulted in three scores that improved predictive potential with sensitivities of between 0.75 and 0.79, specificities between 0.93 and 1.00, and ROC AUCs of 0.89-0.91. SIGNIFICANCE: Lactate levels peak early post-SE, whereas cell counts and ratios do so later. The differing post-event time profiles of lactate levels vs neutrophil count, SIRI, and SII allow incorporation into three separate scores which can assist in differentiating SE from pPNES.

Ex-SPECTing Success: predictors of successful SPECT radiotracer injection during pre-surgical video-EEG admissions.

OBJECTIVES: To determine predictors of successful ictal Single Photon Emission Computed Tomography (SPECT) injections during Epilepsy Monitoring Unit (EMU) admissions for patients undergoing presurgical evaluation for drug resistant focal epilepsy. METHODS: In this retrospective study, consecutive EMU admissions were analysed at a single centre between 2019-2021. All seizures that occurred during the admission were reviewed. 'Injectable seizures' occurred during hours when the radiotracer was available. EMU-level data were analysed to identify factors predictive of an EMU admission with a successful SPECT injection (successful admission). Seizure-level data were analysed to identify factors predictive of an 'injectable seizure' receiving a SPECT injection during the ictal phase (successful injection). A multivariate generalised linear model was used to identify predictive variables. RESULTS: 125 EMU admissions involving 103 patients (median 37 years, IQR27.0-45.5) were analysed. 38.8% of seizures that were eligible for SPECT (n=134) were successfully injected; this represented 17.4% of all seizures (n=298) that occurred during admission. Unsuccessful admissions were most commonly due to a lack of seizures during EMU-SPECT (19.3%) or no 'injectable seizures' (62.3%). Successful EMU-SPECT was associated with baseline seizure frequency >1 per week (95%CI 2.1-3.0, p <0.001) and focal PET hypometabolism (95%CI 2.0-3.7, p <0.001). On multivariate analysis, the only factor associated with successful injection was patients being able to indicate they were having a seizure to staff (95%CI 1.0-4.4, p=0.038). SIGNIFICANCE: Completing a successful ictal SPECT study remains challenging. Baseline seizure frequency of >1 per-week, a PET hypometabolic focus and a patient's ability to indicate seizure onset were identified as predictors of success. These findings may assist EMUs in optimising their SPECT protocols, patient selection, and resource allocation.

Human In Vitro Models of Epilepsy Using Embryonic and Induced Pluripotent Stem Cells.

The challenges in making animal models of complex human epilepsy phenotypes with varied aetiology highlights the need to develop alternative disease models that can address the limitations of animal models by effectively recapitulating human pathophysiology. The advances in stem cell technology provide an opportunity to use human iPSCs to make disease-in-a-dish models. The focus of this review is to report the current information and progress in the generation of epileptic patient-specific iPSCs lines, isogenic control cell lines, and neuronal models. These in vitro models can be used to study the underlying pathological mechanisms of epilepsies, anti-seizure medication resistance, and can also be used for drug testing and drug screening with their isogenic control cell lines.

Inflammation, ictogenesis, and epileptogenesis: An exploration through human disease.

Epilepsy is seen historically as a disease of aberrant neuronal signaling manifesting as seizures. With the discovery of numerous auto-antibodies and the subsequent growth in understanding of autoimmune encephalitis, there has been an increasing emphasis on the contribution of the innate and adaptive immune system to ictogenesis and epileptogenesis. Pathogenic antibodies, complement activation, CD8+ cytotoxic T cells, and microglial activation are seen, to various degrees, in different seizure-associated neuroinflammatory and autoimmune conditions. These aberrant immune responses are thought to cause disruptions in neuronal signaling, generation of acute symptomatic seizures, and, in some cases, the development of long-term autoimmune epilepsy. Although early treatment with immunomodulatory therapies improves outcomes in autoimmune encephalitides and autoimmune epilepsies, patient identification and treatment selection are not always clear-cut. This review examines the role of the different components of the immune system in various forms of seizure disorders including autoimmune encephalitis, autoimmune epilepsy, Rasmussen encephalitis, febrile infection-related epilepsy syndrome (FIRES), and new-onset refractory status epilepticus (NORSE). In particular, the pathophysiology and unique cytokine profiles seen in these disorders and their links with diagnosis, prognosis, and treatment decision-making are discussed.

Genetic prion disease: D178N with 129MV disease modifying polymorphism-a clinical phenotype.

BACKGROUND: Human prion diseases are a group of rare neurological diseases with a minority due to genetic mutations in the prion protein (PRNP) gene. The D178N mutation is associated with both Creutzfeldt-Jakob disease and fatal familial insomnia with the phenotype modified by a polymorphism at codon 129 with the methionine/valine (MV) polymorphism associated with atypical presentations leading to diagnostic difficulty. CASE: We present a case of fatal familial insomnia secondary to a PRNP D178N mutation with 129MV disease modifying polymorphism who had no family history, normal MRI, electroencephalography (EEG), cerebrospinal fluid (CSF) and positron emission tomography findings and a negative real-time quaking-induced conversion result. CONCLUSION: Patients with genetic prion disease may have no known family history and normal EEG, MRI brain and CSF findings. PRNP gene testing should be considered for patients with subacute progressive neurological and autonomic dysfunction.