Carotid free-floating thrombus in COVID-19: a cerebrovascular disorder of cytokine storm-related immunothrombosis.

BACKGROUNDS: Several neurological manifestations, including stroke, have been reported in COVID-19 patients. The putative role of the COVID-19-related hyperinflammatory state in cerebrovascular disorders remains unclear. METHODS: From March 2020 to September 2021, we searched for patients who exhibited an ischemic stroke related to carotid free-floating thrombus (CFFT) to investigate its incidence and relationship with COVID-19. RESULTS: Of 853 ischemic strokes referred to our Stroke Centre during the study period, 5.7% (n = 49) were positive for SARS-CoV-2. Six had CFFT, of which two tested positive for SARS-CoV-2 (2/49 = 4.1%), and four did not (4/802 = 0.5%). The former were two middle-aged men suffering from COVID-19 pneumonia. Floating thrombi were promptly extracted by endarterectomy and endovascular thrombectomy, respectively, with no early and long-term complications. Notably, our COVID-19 patients exhibited little or no atherosclerosis burden on CT angiography, markedly elevated D-dimer levels, and extensive thrombus length. CONCLUSIONS: COVID-19-induced immunothrombosis possibly played a significant pathogenic role in CFFT.

COVID-19 and the Brain: The Neuropathological Italian Experience on 33 Adult Autopsies.

Neurological symptoms are increasingly recognized in SARS-CoV-2 infected individuals. However, the neuropathogenesis remains unclear and it is not possible to define a specific damage pattern due to brain virus infection. In the present study, 33 cases of brain autopsies performed during the first (February-April 2020) and the second/third (November 2020-April 2021) pandemic waves are described. In all the cases, SARS-CoV-2 RNA was searched. Pathological findings are described and compared with those presently published.

Pathological post-mortem findings in lungs infected with SARS-CoV-2.

Italy was the first European nation to be massively infected by SARS-CoV-2. Up to the end of May 2020, more than 33,000 deaths had been recorded in Italy, with a large prevalence among males, those over 75 years of age, and in association with co-morbidities. We describe the lung pathological and immunohistochemical post-mortem findings at the autopsy of nine patients who died of SARS-CoV-2-associated disease. We found in the lung tissues of all patients histological changes consistent with diffuse alveolar damage in various evolution phases ranging from acute exudative to acute proliferative to fibrotic phase. Alveolar damage was associated with prominent involvement of the vascular component in both the interstitial capillaries and the mid-size vessels, with capillary fibrin micro-thrombi, as well as organized thrombi even in medium-sized arteries, in most cases not related to sources of embolism. Eosinophilic infiltrate was also seen, probably reactive to pharmacological treatment. Viral RNA of SARS-CoV-2 was detected from the lung tissues of all the nine patients. Immunohistochemistry for the receptor of the SARS-CoV-2, ACE2, and its priming activator TMPRSS2 revealed that both proteins co-localize in airway cells. In particular, the ACE2 protein was expressed in both endothelial cells and alveolar type I and II pneumocytes in the areas of histological diffuse alveolar damage (DAD). Pneumocytes, but not endothelial cells, also expressed TMPRSS2. There are no distinctive histological features of SARS-CoV-2 infection with respect to SARS-CoV-1 and other DAD with different aetiology. The identification of the cause of death in the course of SARS-CoV-2 infection is more likely multi-factorial. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.