Case report: Rubella virus-associated cutaneous granuloma in an adult with TAP1 deficiency.

Rubella virus-associated granulomas commonly occur in immunocompromised individuals, exhibiting a diverse range of clinical presentations. These manifestations can vary from predominantly superficial cutaneous plaques or nonulcerative nodules to more severe deep ulcerative lesions, often accompanied by extensive necrosis and significant tissue destruction. TAP1 deficiency, an exceedingly rare primary immune-deficiency disorder, presents with severe chronic sino-pulmonary infection and cutaneous granulomas. This report highlights the occurrence of rubella virus-associated cutaneous granulomas in patients with TAP1 deficiency. Notably, the pathogenic mutation responsible for TAP1 deficiency stems from a novel genetic alteration that has not been previously reported. This novel observation holds potential significance for the field of diagnosis and investigative efforts in the context of immunodeficiency disorders.

A Series of 69 COVID-related Dermatoses With Biopsy, Immunohistochemistry With Anti-spike 3, in situ Hybridization and PCR: A Critical Reappraisal of Viral Involvement in COVID-19 Skin Lesions / Serie de 69 dermatosis relacionadas con la COVID con biopsia, estudio inmunohistoquímico con anti-spike 3, hibridación in situ y PCR: Una revisión crítica de la afectación cutánea relacionada con la COVID-19

Background Despite the large number of articles published on skin lesions related to COVID-19, clinicopathological correlation has not been performed consistently and immunohistochemistry to demonstrate spike 3 protein expression has not been validated through RT-PCR. Material and method We compiled 69 cases of patients with confirmed COVID-19, where skin lesions were clinically and histopathologically studied. Immunohistochemistry (IHC) and RT-PCR was performed in skin biopsies. Results After a careful review of the cases, 15 were found to be dermatosis not related to COVID-19, while the rest of the lesions could be classified according to their clinical characteristics as vesicular (4), maculopapular eruptions (41), urticariform (9), livedo and necrosis (10) and pernio-like (5). Although histopathological features were similar to previously reported results, we found two previously unreported findings, maculopapular eruptions with squamous eccrine syringometaplasia and neutrophilic epitheliotropism. IHC showed in some cases endothelial and epidermal staining but RT-PCR was negative in all the tested cases. Thus, direct viral involvement could not be demonstrated. Conclusions Despite presenting the largest series of confirmed COVID-19 patients with histopathologically studied skin manifestations, direct viral involvement was difficult to establish. Vasculopathic and urticariform lesions seem to be those more clearly related to the viral infection, despite IHC or RT-PCR negative results failed to demonstrate viral presence. These findings, as in other dermatological areas, highlight the need of a clinico-pathological correlation to increase knowledge about viral involvement in COVID-19 skin-related lesions (AU)

Antecedentes A pesar del gran número de artículos publicados sobre las lesiones cutáneas relacionadas con la COVID-19, no se ha realizado una correlación clinicopatológica de manera consistente, y no ha sido validado el estudio de inmunohistoquímica para demostrar la expresión de la proteína spike 3 mediante RT-PCR. Material y métodos Recopilamos 69 casos de pacientes con COVID-19 confirmada, en los que se estudiaron las lesiones cutáneas a nivel clínico e histopatológico, habiéndose realizado la prueba inmunohistoquímica (IHQ) y RT-PCR en las biopsias cutáneas. Resultados Tras una revisión detallada de los casos, en 15 de ellos se encontró que la dermatosis no guardaba relación con la COVID-19, mientras que el resto de las lesiones podrían clasificarse de acuerdo con sus características clínicas como vesiculares (4), erupciones maculopapulares (41), urticariformes (9), livedo y necrosis (10) y de tipo perniosis (5). Aunque las características histopatológicas fueron similares a los resultados previamente reportados, encontramos dos hallazgos no reportados previamente: erupciones maculopapulares con siringometaplasia ecrina escamosa y epiteliotropismo neutrofílico. La IHQ reflejó en ciertos casos tinción endotelial y epidérmica, pero la prueba RT-PCR fue negativa en todos los casos probados. Por ello no pudo demostrarse el compromiso viral directo. Conclusiones A pesar de presentar la mayor serie de pacientes con COVID-19 confirmada y manifestaciones cutáneas histopatológicamente estudiadas, el compromiso viral directo fue difícil de establecer. Las lesiones vasculopáticas e urticariformes parecen ser las más claramente relacionadas con la infección viral, a pesar de que los resultados negativos de la IHQ o RT-PCR no pudieron demostrar la presencia viral (AU)

[Articulo traducido] Serie de 69 dermatosis relacionadas con la COVID-19 con biopsia, estudio inmunohistoquímico con anti-spike 3, hibridación in situ y PCR: Una revisión crítica de la afectación cutánea relacionada con la COVID-19 / A Series of 69 COVID-related Dermatoses With Biopsy, Immunohistochemistry With Anti-spike 3, in situ Hybridization and PCR: A Critical Reappraisal of Viral Involvement in COVID-19 Skin Lesions

Antecedentes A pesar del gran número de artículos publicados sobre las lesiones cutáneas relacionadas con la COVID-19, no se ha realizado una correlación clinicopatológica de manera consistente, y no ha sido validado el estudio de inmunohistoquímica para demostrar la expresión de la proteína spike 3 mediante RT-PCR. Material y métodos Recopilamos 69 casos de pacientes con COVID-19 confirmada, en los que se estudiaron las lesiones cutáneas a nivel clínico e histopatológico, habiéndose realizado la prueba inmunohistoquímica (IHQ) y RT-PCR en las biopsias cutáneas. Resultados Tras una revisión detallada de los casos, en 15 de ellos se encontró que la dermatosis no guardaba relación con la COVID-19, mientras que el resto de las lesiones podrían clasificarse de acuerdo con sus características clínicas como vesiculares (4), erupciones maculopapulares (41), urticariformes (9), livedo y necrosis (10) y de tipo perniosis (5). Aunque las características histopatológicas fueron similares a los resultados previamente reportados, encontramos dos hallazgos no reportados previamente: erupciones maculopapulares con siringometaplasia ecrina escamosa y epiteliotropismo neutrofílico. La IHQ reflejó en ciertos casos tinción endotelial y epidérmica, pero la prueba RT-PCR fue negativa en todos los casos probados. Por ello no pudo demostrarse el compromiso viral directo. Conclusiones A pesar de presentar la mayor serie de pacientes con COVID-19 confirmada y manifestaciones cutáneas histopatológicamente estudiadas, el compromiso viral directo fue difícil de establecer. Las lesiones vasculopáticas e urticariformes parecen ser las más claramente relacionadas con la infección viral, a pesar de que los resultados negativos de la IHQ o RT-PCR no pudieron demostrar la presencia viral (AU)

Background Despite the large number of articles published on skin lesions related to COVID-19, clinicopathological correlation has not been performed consistently and immunohistochemistry to demonstrate spike 3 protein expression has not been validated through RT-PCR. Material and method We compiled 69 cases of patients with confirmed COVID-19, where skin lesions were clinically and histopathologically studied. Immunohistochemistry (IHC) and RT-PCR was performed in skin biopsies. Results After a careful review of the cases, 15 were found to be dermatosis not related to COVID-19, while the rest of the lesions could be classified according to their clinical characteristics as vesicular (4), maculopapular eruptions (41), urticariform (9), livedo and necrosis (10) and pernio-like (5). Although histopathological features were similar to previously reported results, we found two previously unreported findings, maculopapular eruptions with squamous eccrine syringometaplasia and neutrophilic epitheliotropism. IHC showed in some cases endothelial and epidermal staining but RT-PCR was negative in all the tested cases. Thus, direct viral involvement could not be demonstrated. Conclusions Despite presenting the largest series of confirmed COVID-19 patients with histopathologically studied skin manifestations, direct viral involvement was difficult to establish. Vasculopathic and urticariform lesions seem to be those more clearly related to the viral infection, despite IHC or RT-PCR negative results failed to demonstrate viral presence. These findings, as in other dermatological areas, highlight the need of a clinico-pathological correlation to increase knowledge about viral involvement in COVID-19 skin-related lesions (AU)

An update on viral-induced cutaneous lymphoproliferative disorders. CME Part I.

Viral-induced cutaneous T-cell lymphomas are an uncommon group of lymphoproliferative disorders characterized by a viral infection of T and natural killer (NK) cells. This group of cutaneous T-cell lymphomas is more commonly encountered in Asians and Native Americans from Central and South America compared with Western populations. Viral-associated lymphoproliferative disorders include a spectrum of entities that range from nonneoplastic lesions, such as chronic active Epstein-Barr virus infection and infective dermatitis to malignant diseases, such as extranodal NK/T-cell lymphoma, hydroa vacciniforme-like T-cell lymphoma, and adult T-cell leukemia/lymphoma. This review article will focus on hydroa vacciniforme-like lymphoproliferative disorder, extranodal NK/T-cell lymphoma, adult T-cell leukemia/lymphoma, lymphomatoid granulomatosis, and Epstein-Barr virus-positive mucocutaneous ulcers. We will review the pathogenesis of these conditions and the challenges of making a timely diagnosis in early-stage disease and discuss the common clinicopathologic manifestations, mutational landscape, and approaches to treat these highly aggressive and frequently lethal types of lymphoma.

SARS-CoV-2 and Skin: New Insights and Perspectives.

The SARS-CoV-2 pandemic has disrupted global health systems and brought the entire globe to its knees. Although born as a disease of the respiratory system, COVID-19 can affect different parts of the body, including the skin. Reports of ongoing skin manifestations of COVID-19 have gradually multiplied, pushing researchers to investigate the etiopathogenic mechanisms underlying these phenomena in more depth. In an attempt to investigate the possible association between SARS-CoV-2, ACE2, TMPRSS2 and skin manifestations, we performed immunohistochemical investigations of the ACE2 receptor and TMPRSS2 in nine skin samples from SARS-CoV-2-positive patients compared to a cohort of healthy controls. Furthermore, after consulting public databases regarding ACE2 mRNA expression in various cell populations resident in the skin, we conducted a literature review aimed at outlining the current state of this topic. We did not find statistically different immuno-expression of ACE2 and TMPRSS2 between the group of SARS-CoV-2-positive patients (nine skin biopsies) and the control group. Regarding ACE2, major immunolabeling was present in the epidermal keratinocytes and, rarely, in the fibroblasts and in the adenomeres of the eccrine sweat glands. Regarding the immune expression of TMPRSS2, we found no significant differences between the two groups, with a weak immune staining only in some skin cytotypes. From the review of the literature, we isolated 35 relevant articles according to the inclusion criteria adopted. ACE2 appears to be a target of SARS-CoV-2, although, other receptor molecules may potentially be implicated, such as TMPRSS2. Future studies with large cases and different molecular investigative methods are needed to further elucidate the mechanisms underlying the skin manifestations of SARS-CoV-2.

Herpes Simplex Virus 1 Can Bypass Impaired Epidermal Barriers upon Ex Vivo Infection of Skin from Atopic Dermatitis Patients.

To infect its human host, herpes simplex virus 1 (HSV-1) must overcome the protective barriers of skin and mucosa. Here, we addressed whether pathological skin conditions can facilitate viral entry via the skin surface and used ex vivo infection studies to explore viral invasion in atopic dermatitis (AD) skin characterized by disturbed barrier functions. Our focus was on the visualization of the onset of infection in single cells to determine the primary entry portals in the epidermis. After ex vivo infection of lesional AD skin, we observed infected cells in suprabasal layers indicating successful invasion in the epidermis via the skin surface which was never detected in control skin where only sample edges allowed viral access. The redistribution of filaggrin, loricrin, and tight-junction components in the lesional skin samples suggested multiple defective mechanical barriers. To dissect the parameters that contribute to HSV-1 invasion, we induced an AD-like phenotype by adding the Th2 cytokines interleukin 4 (IL-4) and IL-13 to healthy human skin samples. Strikingly, we detected infected cells in the epidermis, implying that the IL-4/IL-13-driven inflammation is sufficient to induce modifications allowing HSV-1 to penetrate the skin surface. In summary, not only did lesional AD skin facilitate HSV-1 penetration but IL-4/IL-13 responses alone allowed virus invasion. Our results suggest that the defective epidermal barriers of AD skin and the inflammation-induced altered barriers in healthy skin can make receptors accessible for HSV-1. IMPORTANCE Herpes simplex virus 1 (HSV-1) can target skin to establish primary infection in the epithelium. While the human skin provides effective barriers against viral invasion under healthy conditions, a prominent example of successful invasion is the disseminated HSV-1 infection in the skin of atopic dermatitis (AD) patients. AD is characterized by impaired epidermal barrier functions, chronic inflammation, and dysbiosis of skin microbiota. We addressed the initial invasion process of HSV-1 in atopic dermatitis skin to understand whether the physical barrier functions are sufficiently disturbed to allow the virus to invade skin and reach its receptors on skin cells. Our results demonstrate that HSV-1 can indeed penetrate and initiate infection in atopic dermatitis skin. Since treatment of skin with IL-4 and IL-13 already resulted in successful invasion, we assume that inflammation-induced barrier defects play an important role for the facilitated access of HSV-1 to its target cells.

Cutaneous presentation of disseminated cytomegalovirus infection in a non-transplant patient with hematological malignancy: A case report.

RATIONALE: Cytomegalovirus (CMV) disease is relatively uncommon in nontransplant hematological patients. Moreover, cutaneous manifestations of CMV diseases have scarcely been reported and are probably under-recognized. PATIENT CONCERNS: We describe a patient with large B-cell lymphoma who developed a band-form, erythematous lesion over his left abdomen soon after the second course of rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone chemotherapy. DIAGNOSES: The lesion was initially mistaken for bacterial cellulitis or herpes zoster and was histologically confirmed as cutaneous CMV infection. Subsequent work-up also detected CMV viremia and the presence of CMV meningoencephalitis. INTERVENTIONS: The patient was treated with ganciclovir plus CMV immune globulin followed by foscarnet. OUTCOMES: Although the patient's cutaneous lesion resolved, his cognitive impairment did not recover, and he developed a fatal multi-organ failure 1 month later. LESSONS: Cutaneous CMV disease can herald multisystem involvement and an unfavorable prognosis in immunocompromised hosts. It should be ruled out with biopsy in patients with hematological malignancy who have cutaneous lesions refractory to antibacterial therapy.

The Induced Expression of BPV E4 Gene in Equine Adult Dermal Fibroblast Cells as a Potential Model of Skin Sarcoid-like Neoplasia.

The equine sarcoid is one of the most common neoplasias in the Equidae family. Despite the association of this tumor with the presence of bovine papillomavirus (BPV), the molecular mechanism of this lesion has not been fully understood. The transgenization of equine adult cutaneous fibroblast cells (ACFCs) was accomplished by nucleofection, followed by detection of molecular modifications using high-throughput NGS transcriptome sequencing. The results of the present study confirm that BPV-E4- and BPV-E1^E4-mediated nucleofection strategy significantly affected the transcriptomic alterations, leading to sarcoid-like neoplastic transformation of equine ACFCs. Furthermore, the results of the current investigation might contribute to the creation of in vitro biomedical models suitable for estimating the fates of molecular dedifferentiability and the epigenomic reprogrammability of BPV-E4 and BPV-E4^E1 transgenic equine ACFC-derived sarcoid-like cell nuclei in equine somatic cell-cloned embryos. Additionally, these in vitro models seem to be reliable for thoroughly recognizing molecular mechanisms that underlie not only oncogenic alterations in transcriptomic signatures, but also the etiopathogenesis of epidermal and dermal sarcoid-dependent neoplastic transformations in horses and other equids. For those reasons, the aforementioned transgenic models might be useful for devising clinical treatments in horses afflicted with sarcoid-related neoplasia of cutaneous and subcutaneous tissues.

Cutaneous manifestation of COVID-19: What have we learned an year into the pandemic? / Manifestaciones cutáneas de la COVID-19: ¿Qué hemos aprendido tras un año de pandemia?

Coronavirus disease-19 (COVID-19) is an emerging health situation caused by the “severe acute respiratory syndrome coronavirus 2” (SARS-CoV-2). The ongoing COVID-19 pandemic which emerged from the Chinese city of Wuhan in December 2019 has spread to over 188 countries and infected over 100 million people across the globe in over one year. Most common symptoms of COVID-19 include fever and respiratory illness. Among extrapulmonary signs associated with COVID-19, dermatological manifestations have been increasingly reported from different geographical regions. The exact incidence or prevalence of COVID-19 associated skin manifestation remains largely unknown and the pathophysiological mechanisms are still unclear. In this article, we have attempted to give a comprehensive overview of what has been learned an year into the pandemic on the epidemiology, clinical and histopathological features, pathophysiological mechanisms and clinical management of COVID-19 associated cutaneous manifestations (AU)

La enfermedad por coronavirus de 2019 (COVID-19) es una situación sanitaria emergente causada por el “síndrome respiratorio agudo severo por coronavirus 2” (SARS-CoV-2). La pandemia por COVID-19 en curso, que surgió de la ciudad china de Wuhan en Diciembre de 2019, se ha propagado en 188 países, y ha infectado a más de 100 millones de personas a nivel mundial a lo largo de un año. Los síntomas más comunes de la COVID-19 incluyen fiebre y enfermedad respiratoria. Entre los signos extrapulmonares asociados a COVID-19 se han reportado cada vez más manifestaciones dermatológicas en las diferentes regiones geográficas. La incidencia o prevalencia exactas de las manifestaciones cutáneas asociadas a la COVID-19 son bastante desconocidas, y los mecanismos patofisiológicos siguen sin dilucidarse. En este artículo hemos tratado de aportar una visión general amplia de lo que hemos aprendido en un año de inmersión en la pandemia en cuanto a epidemiología y características clínicas e histopatológicas, mecanismos patofisiológicos y manejo clínico de las manifestaciones cutáneas asociadas a la COVID-19 (AU)

[Artículo traducido] Manifestaciones cutáneas de la COVID-19: ¿Qué hemos aprendido tras un año de pandemia? / Cutaneous Manifestation of COVID-19: What Have we Learned an Year Into the Pandemic?

La enfermedad por coronavirus de 2019 (COVID-19) es una situación sanitaria emergente causada por el “síndrome respiratorio agudo severo por coronavirus 2” (SARS-CoV-2). La pandemia por COVID-19 en curso, que surgió de la ciudad china de Wuhan en Diciembre de 2019, se ha propagado en 188 países, y ha infectado a más de 100 millones de personas a nivel mundial a lo largo de un año. Los síntomas más comunes de la COVID-19 incluyen fiebre y enfermedad respiratoria. Entre los signos extrapulmonares asociados a COVID-19 se han reportado cada vez más manifestaciones dermatológicas en las diferentes regiones geográficas. La incidencia o prevalencia exactas de las manifestaciones cutáneas asociadas a la COVID-19 son bastante desconocidas, y los mecanismos patofisiológicos siguen sin dilucidarse. En este artículo hemos tratado de aportar una visión general amplia de lo que hemos aprendido en un año de inmersión en la pandemia en cuanto a epidemiología y características clínicas e histopatológicas, mecanismos patofisiológicos y manejo clínico de las manifestaciones cutáneas asociadas a la COVID-19 (AU)

Coronavirus disease-19 (COVID-19) is an emerging health situation caused by the “severe acute respiratory syndrome coronavirus 2” (SARS-CoV-2). The ongoing COVID-19 pandemic which emerged from the Chinese city of Wuhan in December 2019 has spread to over 188 countries and infected over 100 million people across the globe in over one year. Most common symptoms of COVID-19 include fever and respiratory illness. Among extrapulmonary signs associated with COVID-19, dermatological manifestations have been increasingly reported from different geographical regions. The exact incidence or prevalence of COVID-19 associated skin manifestation remains largely unknown and the pathophysiological mechanisms are still unclear. In this article, we have attempted to give a comprehensive overview of what has been learned an year into the pandemic on the epidemiology, clinical and histopathological features, pathophysiological mechanisms and clinical management of COVID-19 associated cutaneous manifestations (AU)

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

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiologic agent of coronavirus disease 2019 (COVID-19), is a single-stranded RNA virus whose sequence is known. COVID-19 is associated with a heterogeneous clinical phenotype ranging from asymptomatic to fatal disease. It appears that access to nasopharyngeal respiratory epithelia expressing angiotensin-converting enzyme (ACE) 2, the receptor for SARS-CoV-2, is followed by viral replication in the pulmonary alveolar septal capillary bed. We have demonstrated in earlier studies that incomplete viral particles, termed pseudovirions, dock to deep subcutaneous and other vascular beds, potentially contributing to the prothrombotic state and systemic complement activation that characterizes severe and critical COVID-19. A variety of skin eruptions have been described in the setting of SARS-CoV-2 infection and more recently, after COVID-19 vaccination. The vaccines deliver a laboratory-synthesized mRNA that encodes a protein that is identical to the spike glycoprotein of SARS-CoV-2, allowing the production of immunogenic spike glycoprotein that will then elicit T cell and B cell adaptive immune responses. In this contribution, we review an array of cutaneous manifestations of COVID-19 that provide an opportunity to study critical pathophysiologic mechanisms that underlie all clinical facets of COVID-19, ranging from asymptomatic/mild to severe and critical COVID-19. We classify cutaneous COVID-19 according to underlying pathophysiologic principles. In this regard we propose three main pathways: (1) complement mediated thrombotic vascular injury syndromes deploying the alternative and mannan binding lectin pathways and resulting in the elaboration of cytokines like interleukin 6 from endothelium in the setting of severe and critical COVID-19 and (2) the robust T cell and type I interferon-driven inflammatory and (3) humoral-driven immune complex mediated vasculitic cutaneous reactions observed with mild and moderate COVID-19. Presented are novel data on cutaneous vaccine reactions that manifest a clinical and morphologic parallel with similar eruptions observed in patients with mild and moderate COVID-19 and in some cases represent systemic eczematoid hypersensitivity reactions to a putative vaccine-based antigen versus unmasking subclinical hypersensitivity due to immune enhancing effects of the vaccine. Finally, we demonstrate for the first time the localization of human synthesized spike glycoprotein after the COVID-19 vaccine to the cutaneous and subcutaneous vasculature confirming the ability of SARS-CoV-2 spike glycoprotein to bind endothelium in the absence of intact virus.

Prevalence of Common Viral Skin Infections in Beach Volleyball Athletes.

Viral skin infections often affect the sports community. The aim of this study was to assess the rates, location sites, and seasons of appearance of common viral cutaneous diseases in beach volleyball athletes in Greece. Five hundred and forty-nine beach volleyball athletes participated in this study. The average age was 28.4 years. The viral infections were herpes simplex (type 1), molluscum contagiosum and warts. The measured parameters included: gender, age, the season when athletes may be more susceptible to infections and the location of infection in the body. Practicing information such as the number of training years, number of weekly trainings, and average hours of daily training was also recorded. Incidence rates correlated in relation to age: (a) warts (p < 0.001), molluscum contagiosum (p < 0.001), and herpes simplex (p = 0.001); (b) years of training: warts (p < 0.001), molluscum contagiosum (p < 0.001), and herpes simplex (p = 0.004); (c) average hours of daily training: molluscum contagiosum (p = 0.006) and herpes simplex (p < 0.010). The skin is the largest organ, and the risk of infection should not be underestimated. Prevention, early detection, recognition, and treatment are related to health and athletic performance, but also to the risk of transmission.

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.

SARS-CoV-2 and Skin: The Pathologist's Point of View.

The SARS-CoV-2 pandemic has dramatically changed our lives and habits. In just a few months, the most advanced and efficient health systems in the world have been overwhelmed by an infectious disease that has caused 3.26 million deaths and more than 156 million cases worldwide. Although the lung is the most frequently affected organ, the skin has also resulted in being a target body district, so much so as to suggest it may be a real "sentinel" of COVID-19 disease. Here we present 17 cases of skin manifestations studied and analyzed in recent months in our Department; immunohistochemical investigations were carried out on samples for the S1 spike-protein of SARS-CoV-2, as well as electron microscopy investigations showing evidence of virions within the constituent cells of the eccrine sweat glands and the endothelium of small blood vessels. Finally, we conduct a brief review of the COVID-related skin manifestations, confirmed by immunohistochemistry and/or electron microscopy, described in the literature.

Pathogenesis of COVID-19; Acute Auto-inflammatory Disease (Endotheliopathica & Leukocytoclastica COVIDicus).

BACKGROUND: The pathogenesis of the COVID19 pandemic, that has killed one million nine hundred people and infected more the 90 million until end of 2020, has been studied by many researchers. Here, we try to explain its biological behavior based on our recent autopsy information and review of literature. METHODS: In this study, patients with a positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) result were considered eligible for enrollment. Histopathological examinations were done on 13 people who were hospitalized in Afzalipour hospital, Kerman, Iran. Clinical and laboratory data were reviewed. Tissue examination was done by light microscopy, immunohistochemistry and electron microscopy. RESULTS: The most frequent co-morbidity in the patients was cardiovascular disease. The common initial symptoms of COVID-19 infection were dyspnea and cough. In all cases, the number of white blood cells was higher than the normal range. Common histopathological findings were variable degrees of vasculitis as degenerative to necrotic changes of endothelium and trafficking of inflammatory cells in the vessel wall with fibrinoid necrosis. Tissue damage included interstitial acute inflammatory cells reaction with degenerative to necrotic changes of the parenchymal cells. CD34 and Factor VIII immunohistochemistry staining showed endothelial cell degeneration to necrosis at the vessel wall and infiltration by inflammatory cells. Electron microscopic features confirmed the degenerative damages in the endothelial cells. CONCLUSION: Our histopathological studies suggest that the main focus of the viral damage is the endothelial cells (endotheliopathica) in involved organs. Also, our findings suggest that degeneration of leukocytes occurs at the site of inflammation and release of cytokines (leukocytoclastica) resulting in a cytokine storm.

A Review of COVID-19 Chilblains-like Lesions and Their Differential Diagnoses.

GENERAL PURPOSE: To familiarize wound care practitioners with the differential diagnoses of chilblains-like lesions that could be associated with the complications of COVID-19. TARGET AUDIENCE: This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and nurses with an interest in skin and wound care. LEARNING OBJECTIVES/OUTCOMES: After participating in this educational activity, the participant will:1. Identify the population most often affected by COVID toes.2. Select the assessments that help differentiate the various conditions that cause chilblains-like lesions.3. Choose appropriate treatment options for the various conditions that cause chilblains-like lesions.

This review article focuses on the pathogenesis, clinical features, and diagnostic testing of the common pathologies that can manifest as chilblains-like lesions. These differentials include "COVID toes," Raynaud phenomenon, acrocyanosis, critical limb ischemia, thromboangiitis obliterans, chilblains associated with lupus erythematosus, and idiopathic chilblains. The authors present a helpful mnemonic, ARCTIC, to assist clinicians in recognition and diagnosis.