Heme Oxygenase-1/High Mobility Group Box 1 Pathway May Have a Possible Role in COVID-19 ARDS (Acute Respiratory Distress Syndrome): A Pilot Histological Study.

COVID-19 is a pandemic disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The persistent and excessive inflammatory response can build up a clinical picture that is difficult to manage and potentially fatal. Potent activators of inflammatory phenomena are damage-associated molecular patterns (DAMPs) and, in particular, the high-mobility group box 1 (HMGB1). HMGB1 is an intranuclear protein that is either passively released during hypoxia-related necrosis or actively released by macrophages. Heme oxygenase (HO-1) has an anti-inflammatory effect by inhibiting HMGB1, which could be a therapeutic target to reduce COVID-19 inflammation. In our study, we evaluated CD3, CD4, CD8, HMGB1 and HO-1 in the COVID-19 lung and correlated it to clinical data.

Practical application of Standard Operating Procedures (SOP) Guidelines for COVID-19 autopsies: an Italian experience

Introduction: SARS-CoV-2, responsible for severe human infection with high mortality rate, has been classified as HG3 pathogen. Despite the need to perform autopsy to clarify the pathogenesis of COVID, such procedures are at high risk of contagion due to the direct contact with aerosols and body fluids. To ensure the safety of the personnel against contagion, it is mandatory to follow the SOP for the management of autopsy environment and infected body. Several studies have shown that SARS-CoV-2 persists on inanimate surfaces for a long time and is also ubiquitously detected in many human tissues, even after long time after death. Material and Methods: Many international scientific societies have drowned up various guidelines on biosafety and exposure precautions, but none of these is uniquely adopted. So, in the daily practice our greatest difficulty was to identify SOP adherent to the guidelines but applicable to our reality. In our experience, COVID autopsies were performed accordingly to the following SOP: - COVID mortuary refrigerators - BSL3 autopsy facility - Autopsy saw with aspiration system - PPE: surgical scrub, rubber medical shoes, coverall, shoe leggings, FFP3 mask, waterproof gown or apron, eyes protection, two pairs of medical gloves and one of cut-resistant gloves - Sanitization of surgical tools in autoclave - Sanitization of the environments with VHP - Periodic nasopharyngeal swabs from personnel Results and Conclusions: Our work aims to share our experience and to demonstrate that adopting these measures is effective in reducing risk of infection. In fact, the periodic COVID swabs were negative in 100% of cases.

Inflammatory Skin Lesions in Three SARS-CoV-2 Swab-Negative Adolescents: A Possible COVID-19 Sneaky Manifestation?

Coronavirus disease 19 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is associated with various clinical manifestations, including skin lesions. In particular, during the COVID-19 pandemic lock-down period numerous chilblain-like lesions, mainly located on the feet, were observed in adolescents. The latter were often asymptomatic or associated with very mild respiratory symptoms. Here, we report three cases of acral nodular lesions in SARS-CoV-2 swab-negative adolescents with histological findings of chronic immune-mediated inflammation and immunohistochemical evidence of SARS-CoV-2 spike glycoproteins in endothelial cells and eccrine sweat glands. In one of these cases, the virus presence was confirmed by electron microscopy.