Ischemic stroke shortly after vaccination against SARS-CoV-2: A case-control study.

BACKGROUND AND PURPOSE: Vaccination against SARS-CoV-2 has been associated with rare occurrences of severe venous thromboses. Very little data exist about arterial ischemic strokes. We have assessed the features of ischemic strokes occurring shortly after vaccination against SARS-CoV-2 in the Cremona area, Italy. METHODS: From February 1, to July 31, 2021, all patients with ischemic stroke within four weeks of vaccination against COVID-19 admitted to our stroke unit were consecutively collected, and their main features were compared with those of all other patients with ischemic strokes admitted during the same period. RESULTS: Sixteen strokes after vaccination were collected. They represented 10.5% of all ischemic strokes. Median interval from vaccination was 12 days (range 1-24). Fifteen (93.8%) had received the BNT162b2 (Pfizer-BioNTech) vaccine and 1 (6.2%) the ChAdOx1 nCoV-19 (AstraZeneca). Two patients (12.5%) had a mild thrombocytopenia on admission (128,000 and 142,000/ml), without any evidence of bleeding or venous thrombosis. Thrombolysis and/or thrombectomy were carried out in 4 cases (25.0%). When compared with 137 strokes without recent vaccination, none of the demographic, clinical, and laboratory features of post-vaccination strokes were significantly different. CONCLUSIONS: Ischemic strokes occurring shortly after COVID-19 vaccination at our center were similar to those of non-vaccinated patients. Therefore, the relatively high percentage of such patients probably relates to the very high fraction of elderly people vaccinated against SARS-CoV-2 in the Cremona area, rather than to a consequence of vaccination.

The clinical spectrum of encephalitis in COVID-19 disease: the ENCOVID multicentre study (preprint)

Background: Several preclinical and clinical investigations have argued for nervous system involvement in SARS-CoV-2 infection. Some sparse case reports have described various forms of encephalitis in COVID-19 disease, but very few data have focused on clinical presentations, clinical course, response to treatment and outcomes yet. Objective: to describe the clinical phenotype, laboratory and neuroimaging findings of encephalitis associated with SARS-CoV-2 infection, their relationship with respiratory function and inflammatory parameters and their clinical course and response to treatment. Design: The ENCOVID multicentre study was carried out in 13 centres in northern Italy between February 20th and May 31st, 2020. Only patients with altered mental status and at least two supportive criteria for encephalitis with full infectious screening, CSF, EEG, MRI data and a confirmed diagnosis of SARS-CoV-2 infection were included. Clinical presentation and laboratory markers, severity of COVID-19 disease, response to treatment and outcomes were recorded. Results: Out of 45 cases screened, twenty-five cases of encephalitis positive for SARS-CoV-2 infection with full available data were included. The most common symptoms at onset were delirium (68%), aphasia/dysarthria (24%) and seizures (24%). CSF showed hyperproteinorrachia and/or pleocytosis in 68% of cases whereas SARS-CoV-2 RNA by RT-PCR resulted negative. Based on MRI, cases were classified as ADEM (n=3), limbic encephalitis (LE, n=2), encephalitis with normal imaging (n=13) and encephalitis with MRI alterations (n=7). ADEM and LE cases showed a delayed onset compared to the other encephalitis (p=0.001) and were associated with previous more severe COVID-19 respiratory involvement. Patients with MRI alterations exhibited worse response to treatment and final outcomes compared to other encephalitis. Conclusions and relevance: We found a wide clinical spectrum of encephalitis associated with COVID19 infection, underlying different pathophysiological mechanisms. Response to treatment and final outcome strongly depended on specific CNS-manifestations.