Association of cerebrospinal fluid brain-binding autoantibodies with cognitive impairment in post-COVID-19 syndrome.

BACKGROUND: Neurological symptoms, in particular cognitive deficits, are common in post-COVID-19 syndrome (PCS). There is no approved therapy available, and the underlying disease mechanisms are largely unknown. Besides others, autoimmune processes may play a key role. DESIGN: We here present data of a prospective study conducted between September 2020 and December 2021 and performed at two German University hospitals with specialized Neurology outpatient clinics. Fifty patients with self-reported cognitive deficits as main complaint of PCS and available serum and CSF samples were included. Cell-based assays and indirect immunofluorescence on murine brain sections were used to detect autoantibodies against intracellular and surface antigens in serum and CSF and analyzed for associations with cognitive screening assessment. RESULTS: Clearly abnormal cognitive status (MoCA ≤ 25/30 points) was only seen in 18/50 patients with self-reported cognitive deficits. Most patients (46/50) had normal routine CSF parameters. anti-neuronal autoantibodies were found in 52 % of all patients: n = 9 in serum only, n = 3 in CSF only and n = 14 in both, including those against myelin, Yo, Ma2/Ta, GAD65 and NMDA receptor, but also a variety of undetermined epitopes on brain sections. These included cerebral vessel endothelium, Purkinje neurons, granule cells, axon initial segments, astrocytic proteins and neuropil of basal ganglia or hippocampus as well as a formerly unknown perinuclear rim pattern. Pathological MoCA results were associated with the presence of anti-neuronal antibodies in CSF (p = 0.0004). CONCLUSIONS: Autoantibodies targeting brain epitopes are common in PCS patients and strongly associate with pathological cognitive screening tests, in particular when found in CSF. Several underlying autoantigens still await experimental identification. Further research is needed to inform on the clinical relevance of these autoantibodies, including controlled studies that explore the potential efficacy of antibody-depleting immunotherapy in PCS.

A Neurological Outpatient Clinic for Patients With Post-COVID-19 Syndrome - A Report on the Clinical Presentations of the First 100 Patients.

Background and Objectives: Neurological and psychiatric symptoms are frequent in patients with post-COVID-19 syndrome (PCS). Here, we report on the clinical presentation of the first 100 patients who presented to our PCS Neurology outpatient clinic ≥12 weeks after the acute infection with SARS-CoV-2. To date, PCS is only defined by temporal connection to SARS-CoV-2 infection. Identification of clinical phenotypes and subgroups of PCS is urgently needed. Design: We assessed clinical data of our first 100 ambulatory patients regarding clinical presentations; self-questionnaires focusing on daytime sleepiness, mood, and fatigue; and a screening assessment for detecting cognitive impairment. Results: A total of 89% of the patients presenting to the Neurology outpatient clinic had an initially mild course of COVID-19 and had not been hospitalized. The majority of the patients were female (67 vs. 33% male). The most frequent symptom reported was cognitive impairment (72%). There were 30% of patients who reported cognitive deficits and scored below 26 points on the Montreal Cognitive Assessment Scale. Fatigue (67%), headache (36%), and persisting hyposmia (36%) were also frequently reported; 5.5% of all patients showed signs of severe depression. Discussion: To our knowledge, this is the first report of patient data of a PCS Neurology outpatient clinic. Neurological sequelae also exist for more than 3 months after mainly mild SARS-CoV-2 acute infections. The reported symptoms are in accordance with recently published data of hospitalized patients.

Stroke Admissions, Stroke Severity, and Treatment Rates in Urban and Rural Areas During the COVID-19 Pandemic.

Background: Many regions worldwide reported a decline of stroke admissions during the early phase of the coronavirus disease 2019 (COVID-19) pandemic. It remains unclear whether urban and rural regions experienced similar declines and whether deviations from historical admission numbers were more pronounced among specific age, stroke severity or treatment groups. Methods: We used registry datasets from (a) nine acute stroke hospitals in Berlin, and (b) nine hospitals from a rural TeleNeurology network in Northeastern Germany for primary analysis of 3-week-rolling average of stroke/TIA admissions before and during the COVID-19 pandemic. We compared course of stroke admission numbers with regional cumulative severe acute respiratory syndrome coronavirus 2 (Sars-CoV-2) infections. In secondary analyses, we used emergency department logs of the Berlin Charité University hospital to investigate changes in age, stroke severity, and thrombolysis/thrombectomy frequencies during the early regional Sars-CoV-2 spread (March and April 2020) and compared them with preceding years. Results: Compared to past years, stroke admissions decreased by 20% in urban and 20-25% in rural hospitals. Deviations from historical averages were observable starting in early March and peaked when numbers of regional Sars-CoV-2 infections were still low. At the same time, average admission stroke severity and proportions of moderate/severe strokes (NIHSS >5) were 20 and 20-40% higher, respectively. There were no relevant deviations observed in proportions of younger patients (<65 years), proportions of patients with thrombolysis, or number of thrombectomy procedures. Stroke admissions at Charité subsequently rebounded and reached near-normal levels after 4 weeks when the number of new Sars-CoV-2 infections started to decrease. Conclusions: During the early pandemic, deviations of stroke-related admissions from historical averages were observed in both urban and rural regions of Northeastern Germany and appear to have been mainly driven by avoidance of admissions of mildly affected stroke patients.

High frequency of cerebrospinal fluid autoantibodies in COVID-19 patients with neurological symptoms.

BACKGROUND: COVID-19 intensive care patients can present with neurological syndromes, usually in the absence of SARS-CoV-2 in cerebrospinal fluid (CSF). The recent finding of some virus-neutralizing antibodies cross-reacting with brain tissue suggests the possible involvement of specific autoimmunity. DESIGN: Blood and CSF samples from eleven critically ill COVID-19 patients presenting with unexplained neurological symptoms including myoclonus, oculomotor disturbance, delirium, dystonia and epileptic seizures, were analyzed for anti-neuronal and anti-glial autoantibodies. RESULTS: Using cell-based assays and indirect immunofluorescence on unfixed murine brain sections, all patients showed anti-neuronal autoantibodies in serum or CSF. Antigens included intracellular and neuronal surface proteins, such as Yo or NMDA receptor, but also various specific undetermined epitopes, reminiscent of the brain tissue binding observed with certain human monoclonal SARS-CoV-2 antibodies. These included vessel endothelium, astrocytic proteins and neuropil of basal ganglia, hippocampus or olfactory bulb. CONCLUSION: The high frequency of autoantibodies targeting the brain in the absence of other explanations suggests a causal relationship to clinical symptoms, in particular to hyperexcitability (myoclonus, seizures). Several underlying autoantigens and their potential molecular mimicry with SARS-CoV-2 still await identification. However, autoantibodies may already now explain some aspects of multi-organ disease in COVID-19 and can guide immunotherapy in selected cases.