The skin as a critical window in unveiling the pathophysiologic principles of COVID-19

Tumor necrosis factor ALPHA Inhibitor Associated Köhlmeier-Degos Disease as a Novel Iatrogenic Paradigm That Underscores Excessive Type I Interferon in Its Pathogenesis

ABSTRACT

Malignant atrophic papulosis/Köhlmeier-Degos disease was first described in 1941 by Köhlmeier in an anecdotal case report that described a young man who presented with extensive multiple intestinal perforations and a papular skin rash. Köhlmeier-Degos disease represents a unique vasculopathy targeting both the microvasculature and the arterial system. One of its most characteristic features is reflected by the discrete multifocal depressed porcelain lesions involving the skin and gastrointestinal tract. The pathological findings are striking and can be broadly categorized into those that are vascular in nature versus extravascular matrix production in the context of extensive extravascular hyaluronic acid and collagen deposition. A dynamic evolutionary morphology is observed not only clinically but also histologically. The microvascular alterations are particularly evident in the skin and are characterized by endothelial cell necrosis with subsequent endothelial cell detachment accompanied by intraluminal fibrin deposition, defining a thrombogenic microangiopathy that in later stage lesions is typically pauci-inflammatory. The arterial lesions are very distinctive and include significant neointimal proliferation with vascular luminal occlusion by amorphous plugs of collagen intimately admixed with platelets. Pathogenetically enhanced type I interferon signaling and endothelial cell injury mediated by the membranolytic attack complex (ie, C5b-9) are key in the evolution of the thrombotic microvascular and obliterative fibrosing arteriopathic changes. We describe a case of Köhlmeier-Degos disease that developed in the setting of tumor necrosis factor (TNF)-alpha inhibitor therapy with the drug golimumab. The clinical features, light microscopic findings, and a pathophysiologic paradigm based on the critical role of TNF-alpha in controlling the type I interferon response are discussed.

The correlation between corona virus disease 2019 and alopecia areata: a literature review

Corona virus disease 2019(COVID-19) is one of the most serious respiratory pandemic diseases threatening human health for centuries. Alopecia areata (AA) is a sudden patchy hair loss, an autoimmune disease, which seriously affects the image and mental health of patients. Evidence shows that the risk of autoimmune diseases significantly increases after COVID-19, and is positively correlated with the severity, with a significant increase in the risk of alopecia in those over 40 years old. The relationship between COVID-19 and AA has become a hot topic of current research. Strengthening the research on the correlation between COVID-19 and AA can help to identify and protect susceptible populations at an early stage. This article reviews the research progress on the epidemiological background of COVID-19 and AA, the situation and possible mechanisms of AA induced by COVID-19 or COVID-19 vaccination, and potential treatment methods.

The most common skin symptoms in young adults and adults related to SARS-CoV-2 virus infection

Scientists from various areas of the world indicate in their studies that skin lesions occur in the course of infection with the SARS-CoV-2 virus. This article is a review of the most frequently described cutaneous manifestations of SARS-CoV-2 virus infection and the potential pathophysiology of their development, as well as information on abnormalities in histopathological tests. The article describes the impact of some factors related to the COVID-19 pandemic on the exacerbation of chronic dermatological diseases. This work was constructed on the basis of 142 research studies, reviews, and meta-analyses, focusing on the methods and materials used in individual works as well as the results and conclusions resulting from them. Some skin lesions may be a potential prognostic marker of the course of the disease and may also be a prodromal symptom or the only symptom of SARS-CoV-2 virus infection. Stress related to the COVID-19 pandemic may exacerbate some chronic dermatological diseases. A correlation was observed between the type of skin lesions and the patient's age. The occurrence of skin diseases may also be influenced by drugs used to treat infections caused by SARS-CoV-2. A relationship was observed between the patient's ethnic origin and skin lesions occurring in the course of COVID-19. There is a need to further diagnose the cutaneous manifestations of SARS-CoV-2 infection and to learn the detailed pathomechanism of their occurrence in order to better understand the essence of the disease and find an appropriate treatment method.

SARS-CoV-2-Induced Vasculitic Skin Lesions Are Associated with Massive Spike Protein Depositions in Autophagosomes

In patients infected with severe acute respiratory syndrome coronavirus 2, vasculopathic changes of the skin are associated with a severe prognosis. However, the pathogenesis of this vasculopathy is not conclusively clarified. In this study, 25 prospectively collected skin samples from patients with COVID-19-related skin lesions were examined for vasculopathic changes and, in case of vasculitis, were further analyzed with electron microscopy and immunohistochemistry. Vasculopathy was observed in 76% of all COVID-19-related inflammatory skin lesions. Visual endothelial changes without manifest leukocytoclastic vasculitis were found in 60% of the COVID-19-related skin lesions, whereas leukocytoclastic vasculitis was diagnosed in 16%. In the cases of vasculitis, there were extensive spike protein depositions in microvascular endothelial cells that colocalized with the autophagosome proteins LC3B and LC3C. The autophagy protein complex LC3-associated endocytosis in microvascular endothelial cells seems to be an important pathogenic factor for severe acute respiratory syndrome coronavirus 2-related vasculitis in the skin. On ultrastructural morphology, the vasculitic process was dominated by intracellular vesicle formation and endothelial cell disruption. Direct presence of severe acute respiratory syndrome coronavirus 2 particles in the skin was not observed. Therefore, our results suggest that instead of direct viral infection, dermal vasculitic lesions in COVID-19 are caused by severe acute respiratory syndrome coronavirus 2 spike protein deposition followed by endothelial damage with activation of autophagy.

Endothelial activation and damage as a common pathological substrate in different pathologies and cell therapy complications

The endothelium is a biologically active interface with multiple functions, some of them common throughout the vascular tree, and others that depend on its anatomical location. Endothelial cells are continually exposed to cellular and humoral factors, and to all those elements (biological, chemical, or hemodynamic) that circulate in blood at a certain time. It can adapt to different stimuli but this capability may be lost if the stimuli are strong enough and/or persistent in time. If the endothelium loses its adaptability it may become dysfunctional, becoming a potential real danger to the host. Endothelial dysfunction is present in multiple clinical conditions, such as chronic kidney disease, obesity, major depression, pregnancy-related complications, septic syndromes, COVID-19, and thrombotic microangiopathies, among other pathologies, but also in association with cell therapies, such as hematopoietic stem cell transplantation and treatment with chimeric antigen receptor T cells. In these diverse conditions, evidence suggests that the presence and severity of endothelial dysfunction correlate with the severity of the associated disease. More importantly, endothelial dysfunction has a strong diagnostic and prognostic value for the development of critical complications that, although may differ according to the underlying disease, have a vascular background in common. Our multidisciplinary team of women has devoted many years to exploring the role of the endothelium in association with the mentioned diseases and conditions. Our research group has characterized some of the mechanisms and also proposed biomarkers of endothelial damage. A better knowledge would provide therapeutic strategies either to prevent or to treat endothelial dysfunction.

Progressive Observation of Covid-19 Vaccination Effects on Skin-Cellular Structures by Use of Intelligent Laser Speckle Classification (ILSC) Technique

The recent pandemic showed that the current global research strategies on vaccine development in an emergency period necessitates more optimized supplementary techniques to observe instant progressive vaccines' subtle effects on human metabolisms to make better and speedy evolutionary health assessments. To fill this gap, we have followed a multi-disciplinary approach exploiting AI, laser-optics, and specific imaging methods. The proposed technique can make progressive observations on Covid-19 Astra Zeneca vaccination effects on skin cellular network by use of the well-established technique-Intelligent Laser Speckle Classification (ILSC), as Covid-19 is a skin-affecting systemic disease. The method also managed to distinguish between three different subject groups via their laser speckle skin image samplings, grouped as early-vaccinated, late-vaccinated and non-vaccinated participants. The results have proven that the ILSC technique, in association with the parametrically optimised Bayesian network, can classify hidden skin changes of vaccinated and non-vaccinated individuals up to 90% accuracy and is also capable of detecting instant progressive developments pertaining to skin cellular properties. The proposed method has also proven that the continuous Covid-19 vaccine effect on the sub-skin layers can be observable by high frequency and speedy non-invasive data collection in real-time with high reliability.

Abnormal thrombosis and neutrophil activation increase hospital-acquired sacral pressure injuries and morbidity in COVID-19 patients

Hospitalized patients have an increased risk of developing hospital-acquired sacral pressure injury (HASPI). However, it is unknown whether SARS-CoV-2 infection affects HASPI development. To explore the role of SARS-CoV-2 infection in HASPI development, we conducted a single institution, multi-hospital, retrospective study of all patients hospitalized for ≥5 days from March 1, 2020 to December 31, 2020. Patient demographics, hospitalization information, ulcer characteristics, and 30-day-related morbidity were collected for all patients with HASPIs, and intact skin was collected from HASPI borders in a patient subset. We determined the incidence, disease course, and short-term morbidity of HASPIs in COVID-19(+) patients, and characterized the skin histopathology and tissue gene signatures associated with HASPIs in COVID-19 disease. COVID-19(+) patients had a 63% increased HASPI incidence rate, HASPIs of more severe ulcer stage (OR 2.0, p<0.001), and HASPIs more likely to require debridement (OR 3.1, p=0.04) compared to COVID-19(-) patients. Furthermore, COVID-19(+) patients with HASPIs had 2.2x increased odds of a more severe hospitalization course compared to COVID-19(+) patients without HASPIs. HASPI skin histology from COVID-19(+) patients predominantly showed thrombotic vasculopathy, with the number of thrombosed vessels being significantly greater than HASPIs from COVID-19(-) patients. Transcriptional signatures of a COVID-19(+) sample subset were enriched for innate immune responses, thrombosis, and neutrophil activation genes. Overall, our results suggest that immunologic dysregulation secondary to SARS-CoV-2 infection, including neutrophil dysfunction and abnormal thrombosis, may play a pathogenic role in development of HASPIs in patients with severe COVID-19.

Cutaneous manifestations of COVID-19 and COVID-19 vaccination

In December 2019, a new infectious pathogen named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was identified in Wuhan, China. Transmitted through respiratory droplets, SARS-CoV-2 is the causative pathogen of coronavirus disease 2019 (COVID-19). Although this new COVID-19 infection is known to cause primarily interstitial pneumonia and respiratory failure, it is often associated with cutaneous manifestations as well. These manifestations with COVID-19 can be classified into seven categories: (i) chilblain-like skin eruption (e.g., COVID toes), (ii) urticaria-like skin eruption, (iii) maculopapular lesions, (iv) vesicular eruptions, (v) purpura, (vi) livedo reticularis and necrotic lesions, (vii) urticarial vasculitis, and others such as alopecia and herpes zoster. The pathogenesis of skin eruptions can be broadly divided into vasculitic and inflammatory skin eruptions. Various cutaneous adverse reactions have also been observed after COVID-19 mRNA vaccination. The major cutaneous adverse reactions are type I hypersensitivity (urticaria and anaphylaxis) and type IV hypersensitivity (COVID arm and erythema multiform). Autoimmune-mediated reactions including bullous pemphigus, vasculitis, vitiligo, and alopecia areata have also been reported. Several cases with chilblain-like lesions and herpes zoster after COVID-19 mRNA vaccination have been published. Various skin diseases associated with COVID-19 and COVID-19 vaccination have been reported, and the mechanism has been partly elucidated. In the process, for example, some papers have reported that it is not related to COVID-19 infection, although it was initially called COVID-toe and considered a COVID-19-associated cutaneous eruption. In fact, some COVID-19-associated skin reactions are indistinguishable from drug eruptions. In the future, the mechanisms of COVID-19- or COVID-19 vaccine-associated skin reactions need to be elucidated and verification of causal relationships is required.

Cutaneous vasculitis and vasculopathy in the era of COVID-19 pandemic

Cutaneous vasculitides encompass a heterogeneous group of clinicopathological entities, which may occur as single-organ vasculitis of the skin or present as skin-limited variant of systemic vasculitis (i.e., skin-limited ANCA-associated vasculitis), and are triggered by various factors, including infections, drugs and vaccines. The COVID-19 pandemic has challenged us with a variety of both disease- and vaccine-associated skin manifestations, including vasculitis. Among the latter, cutaneous small-vessel vasculitis, previously known as leukocytoclastic vasculitis, seems to be the most reported in either scenario, i.e., natural infection and vaccination. Vasculopathy without true vasculitic changes on histology develops in but a minority of cases, mostly severe/critical COVID-19 patients, and appears to be the result of endothelial injury due to pauci-immune thromboembolic mechanisms. Herein, we provide an overview of the available literature on COVID-19-associated and anti-SARS-CoV-2-vaccine-associated cutaneous vasculitis. Although evidence is mostly limited to isolated reports, with a proportion of cases lacking histopathological confirmation, ample overlap with pre-pandemic forms is shown.

[Skin manifestations of COVID-19 and after COVID-19 vaccination]

Coronavirus disease 2019 (COVID-19) is a systemic disease induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that frequently presents with skin manifestations. The five most common skin lesions are pseudo-chilblain and maculopapular, urticarial, vesicular, and livedo/necrotizing skin lesions. These skin lesions are of diagnostic and prognostic relevance. For example, in children, typical skin lesions may indicate a life-threatening inflammatory syndrome, which rarely occurs after corona infection. Skin lesions have also been described after COVID-19 vaccination. These usually show an uncomplicated, self-limiting course and therefore do not represent a contraindication for completing the vaccination status in the vast majority of cases.

Case Report: Idiopathic Subcutaneous Thrombotic Vasculopathy

Lower extremity ulcers have significant morbidity, with treatment determined by the underlying disorder. Reported is a 32-year-old female presenting with small skin nodules and bruises across her legs 4 weeks following her second COVID vaccination. These lesions progressed into large, necrotic ulcers over several months. Initial work-up showed widespread pannicular thrombotic vasculopathy with ischemic skin necrosis. The tissue was negative for calcification on Von Kossa histochemistry, and a working diagnosis of subcutaneous thrombotic vasculopathy was suggested. The ulcers progressed despite treatments with corticosteroids, therapeutic anticoagulation, intravenous immunoglobulin, plasmapheresis, sodium thiosulfate, wound care, and repeat debridement. Later debridement specimens demonstrated rare vascular and pannicular calcifications. This finding supports the hypothesis that subcutaneous thrombotic vasculopathy is a precursor to calciphylaxis, the patient’s current working diagnosis. However, based on the patient’s entire clinical picture, a definitive diagnosis has yet to be found. This report highlights the challenges of working with rare diseases and the importance of multidisciplinary cooperation.

COVID-19 Vasculitis and vasculopathy-Distinct immunopathology emerging from the close juxtaposition of Type II Pneumocytes and Pulmonary Endothelial Cells

The SARS-CoV-2 virus ACE-2 receptor utilization for cellular entry and the defined ACE-2 receptor role in cardiovascular medicine hinted at dysregulated endothelial function or even direct viral endotheliitis as the key driver of severe COVID-19 vascular immunopathology including reports of vasculitis. In this article, we critically review COVID-19 immunopathology from the vasculitis perspective and highlight the non-infectious nature of vascular endothelial involvement in severe COVID-19. Whilst COVID-19 lung disease pathological changes included juxta-capillary and vascular macrophage and lymphocytic infiltration typical of vasculitis, we review the evidence reflecting that such “vasculitis” reflects an extension of pneumonic inflammatory pathology to encompass these thin-walled vessels. Definitive, extrapulmonary clinically discernible vasculitis including cutaneous and cardiac vasculitis also emerged- namely a dysregulated interferon expression or “COVID toes” and an ill-defined systemic Kawasaki-like disease. These two latter genuine vasculitis pathologies were not associated with severe COVID-19 pneumonia. This was distinct from cutaneous vasculitis in severe COVID-19 that demonstrated pauci-immune infiltrates and prominent immunothrombosis that appears to represent a novel immunothrombotic vasculitis mimic contributed to by RNAaemia or potentially diffuse pulmonary venous tree thrombosis with systemic embolization with small arteriolar territory occlusion, although the latter remains unproven. Herein, we also performed a systematic literature review of COVID-19 vasculitis and reports of post-SARS-CoV-2 vaccination related vasculitis with respect to the commonly classified pre-COVID vasculitis groupings. Across the vasculitis spectrum, we noted that Goodpasture’s syndrome was rarely linked to natural SARS-CoV-2 infection but not vaccines. Both the genuine vasculitis in the COVID-19 era and the proposed vasculitis mimic should advance the understanding of both pulmonary and systemic vascular immunopathology.

Post-acute sequelae of COVID-19 (PASC): a meta-narrative review of pathophysiology, prevalence, and management

Coronavirus Disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Over 220 countries and territories have been affected by this virus, and the infection rate has continued to rise. As patients recover from the virus, many are experiencing lingering symptoms. Understanding the impact of demographics and comorbidities on symptom prevalence, manifestations, and severity is not only relevant during acute infection, it is critical to the clinical management of patients with post-acute sequelae of COVID-19, also known as PASC. Herein, we provide a comprehensive review on the most recent research related to PASC. Specifically, we focus on the description of the disorder itself, compared to acute COVID-19, and which types of patients are most affected by long-term sequelae. Further, we share recommendations for management of the most common complications of PASC.

Identification, Mechanism, and Treatment of Skin Lesions in COVID-19: A Review

Coronavirus disease 2019 (COVID-19) is a multisystem disease caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), that primarily causes respiratory symptoms. However, an increasing number of cutaneous manifestations associated with this disease have been reported. The aim of this study is to analyze the scientific literature on cutaneous manifestations associated with SARS-CoV-2 by means of a narrative literature review until June 2021. The search was conducted in the following electronic databases: Medline (PubMed), SciELO, and Cochrane Library Plus. The most common cutaneous manifestations in patients with COVID-19 are vesicular eruptions, petechial/purpuric rashes, acral lesions, liveoid lesions, urticarial rash, and maculopapular-erythematous rash. These manifestations may be the first presenting symptoms of SARS-CoV-2 infection, as is the case with acral lesions, vesicular eruptions, and urticaria. In relation to severity, the presence of liveoid lesions may be associated with a more severe course of the disease. Treatment used for dermatological lesions includes therapy with anticoagulants, corticosteroids, and antihistamines. Knowledge of the dermatologic manifestations associated with SARS-CoV-2 contributes to the diagnosis of COVID-19 in patients with skin lesions associated with respiratory symptoms or in asymptomatic patients. In addition, understanding the dermatologic lesions associated with COVID-19 could be useful to establish a personalized care plan.