The Dysregulation of the Monocyte-Dendritic Cell Interplay Is Associated with In-Hospital Mortality in COVID-19 Pneumonia (preprint)

Background: The monocyte-phagocyte system (MPS), including monocytes/macrophages and dendritic cells (DCs), plays a key role in anti-viral immunity. We aimed to analyze the prognostic value of the MPS components on in-hospital mortality in a cohort of 58 patients (M/F ; mean ageSD years) with COVID-19 pneumonia and 22 age- and sex-matched healthy controls. Methods: We measured frequencies and absolute numbers of peripheral blood CD169+ monocytes, conventional CD1c+ and CD141+ (namely cDC2 and cDC1), and plasmacytoid CD303+ DCs by means of multi-parametric flow cytometry. A gene profile analysis of 770 immune-inflammatory related human genes and 20 SARS-CoV-2 genes was also performed. Results: Median frequencies and absolute counts of CD169-expressing monocytes were significantly higher in COVID-19 patients than in controls (p 0.04 and p 0.01, respectively). Conversely, percentages and absolute numbers of all DC subsets were markedly depleted in patients (p

Lesson by SARS-Cov 2 disease (COVID-19): whole body CT angiography detection of relevant and other/incidental systemic vascular findings (preprint)

Objectives: The aim of our study was to assess the frequency distribution of relevant and incidental vascular events in a retrospective cohort of 42 COVID-19 patients. Methods: All patients were studied by whole-body CT angiography.Twenty-three out of 42 patients were admitted to the intensive care unit (ICU). Results: Relevant vascular events were recorded in the 71.4% of the whole study population. Pulmonary embolism was the most frequent one both in ICU and no-ICU cases (56.5% vs10.5%, p=0.002). Ischemic infarction of other organs was affecting with an increasing prevalence the gut, the spleen, the liver, the brain and the kidney, with a simultaneous ischemic occurrence in some cases. Multi-focal venous thrombosis was also represented especially in ICU patients (p=0.005). Among incidental findings, splanchnic vessels little-size aneurysms were reported in the 40% of the whole population, with relative frequencies similarly distributed in ICU and no-ICU patients.Conclusions: Vascular involvement is not negligible in COVID-19 and should be carefully investigated as may significantly affect disease behavior and prognosis.