Lymphocytic vasculitis in livedoid vasculopathy: A report of 137 cases.

BACKGROUND: Livedoid vasculopathy (LV) is characterized by fibrin deposition and thrombosis in the small vessels of the superficial dermis. It is widely recognized as an occlusive disease, which is primarily treated with anticoagulation therapy. METHODS: We retrospectively analyzed the clinical and histopathological characteristics of patients diagnosed with LV at a tertiary dermatology department to explore the characteristics of lymphocytic vasculitis in LV. The frequency of vasculitis and the types of vessels involved were examined based on the diameters and elastic fiber distribution of the involved vessels. In addition, the immunophenotypes of infiltrating lymphocytes were analyzed. RESULTS: In a large retrospective series including 358 LV cases, we identified 137 (38.3%) cases of lymphocytic vasculitis. Among them, 48 cases involved medium-sized vessels, including arterioles and venules, whereas 89 cases involved only small vessels. In addition, 12 cases displayed a segmental distribution of vasculitis. The infiltrating lymphocytes were mainly T cells, with dominant cells stained positive for CD4. CONCLUSIONS: Lymphocytic vasculitis forms part of the histological spectrum of LV, affecting both medium-sized and small vessels. It is possible that the occlusion of small vessels may represent a phenomenon secondary to lymphocytic vasculitis.

Dermatological Lesions of Cholesterol Embolisation Syndrome and Kaposi Sarcoma Mimic Primary Systemic Vasculitis: Case report study.

Primary systemic vasculitis can present with a wide spectrum of manifestations ranging from systemic non-specific features such as fever, malaise, arthralgia and myalgia to specific organ damage. We describe two cases of cholesterol embolisation syndrome and Kaposi sarcoma mimicking primary systemic vasculitis, both of which were characterised by features such as livedo reticularis, blue toe syndrome, a brown purpuric skin rash and positive perinuclear anti-neutrophil cytoplasmic antibodies associated with Kaposi sarcoma. Establishing the right diagnosis was challenging and thus this report aimed to highlight the possible ways to distinguish them from primary systemic vasculitis.

A clinicopathological description of COVID-19-induced chilblains (COVID-toes) correlated with a published literature review.

BACKGROUND: The abundance of publications of COVID-19-induced chilblains has resulted in a confusing situation. METHODS: This is a prospective single-institution study from 15 March to 13 May 2020. Thirty-two patients received PCR nasopharyngeal swabs. Of these, 28 patients had a thoracic CT-scan, 31 patients had blood and urine examinations, 24 patients had skin biopsies including immunohistochemical and direct immunofluorescence studies, and four patients had electron microscopy. RESULTS: COVID-19-induced chilblains are clinically and histopathologically identical to chilblains from other causes. Although intravascular thrombi are sometimes observed, no patient had a systemic coagulopathy or severe clinical course. The exhaustive clinical, radiological, and laboratory work-up in this study ruled-out other primary and secondary causes. Electron microscopy revealed rare, probable viral particles whose core and spikes measured from 120 to 133 nm within endothelium and eccrine glands in two cases. CONCLUSION: This study provides further clinicopathologic evidence of COVID-19-related chilblains. Negative PCR and antibody tests do not rule-out infection. Chilblains represent a good prognosis, occurring later in the disease course. No systemic coagulopathy was identified in any patient. Patients presenting with acral lesions should be isolated, and chilblains should be distinguished from thrombotic lesions (livedo racemosa, retiform purpura, or ischemic acral necrosis).

Cutaneous manifestations of antiphospholipid syndrome.

Antiphospholipid syndrome (APS) is an acquired thrombophilic disorder in which autoantibodies are produced against a variety of phospholipids and phospholipid-binding proteins. The purpose of this article is to review cutaneous findings in patients with APS diagnosis. An overview regarding prevalence, description, pathogenesis and histopathology, are described for cutaneous manifestations of APS.

The differing pathophysiologies that underlie COVID-19-associated perniosis and thrombotic retiform purpura: a case series.

BACKGROUND: There are two distinctive acral manifestations of COVID-19 embodying disparate clinical phenotypes. One is perniosis occurring in mildly symptomatic patients, typically children and young adults; the second is the thrombotic retiform purpura of critically ill adults with COVID-19. OBJECTIVES: To compare the clinical and pathological profiles of these two different cutaneous manifestations of COVID-19. METHODS: We compared the light microscopic, phenotypic, cytokine and SARS-CoV-2 protein and RNA profiles of COVID-19-associated perniosis with that of thrombotic retiform purpura in critical patients with COVID-19. RESULTS: Biopsies of COVID-19-associated perniosis exhibited vasocentric and eccrinotropic T-cell- and monocyte-derived CD11c+ , CD14+ and CD123+ dendritic cell infiltrates. Both COVID-associated and idiopathic perniosis showed striking expression of the type I interferon-inducible myxovirus resistance protein A (MXA), an established marker for type I interferon signalling in tissue. SARS-CoV-2 RNA, interleukin-6 and caspase 3 were minimally expressed and confined to mononuclear inflammatory cells. The biopsies from livedo/retiform purpura showed pauci-inflammatory vascular thrombosis without any MXA decoration. Blood vessels exhibited extensive complement deposition with endothelial cell localization of SARS-CoV-2 protein, interleukin-6 and caspase 3; SARS-CoV-2 RNA was not seen. CONCLUSIONS: COVID-19-associated perniosis represents a virally triggered exaggerated immune reaction with significant type I interferon signaling. This is important to SARS-CoV-2 eradication and has implications in regards to a more generalized highly inflammatory response. We hypothesize that in the thrombotic retiform purpura of critically ill patients with COVID-19, the vascular thrombosis in the skin and other organ systems is associated with a minimal interferon response. This allows excessive viral replication with release of viral proteins that localize to extrapulmonary endothelium and trigger extensive complement activation.

Clinical and Histopathologic Characteristics of the Main Causes of Vascular Occusion - Part II: Coagulation Disorders, Emboli, and Other. / Dermatopatología de la oclusión intraluminal vascular: parteII (coagulopatías, émbolos y miscelánea).

Vascular occlusion has multiple, diverse clinical manifestations, some of which can have grave consequences for patients. It also has a wide variety of causes, including thrombi, which we recently addressed in partI of this review. In this second part, we look at additional causes of vascular occlusion.

Portal vein thrombosis, livedo reticularis, polymicrobial sepsis and high antiphospholipid antibody titers in a newborn: A clinicopathological conference of antiphospholipid-associated neonatal syndrome.

Neonatal Antiphospholipid syndrome (APS) is a rare disease related to transplacental passage of antiphospholipid (aPL) antibodies from the mother or de novo production of aPL in a newborn. Neonatal aPL antibodies have rarely been associated with thrombosis. We describe a 5-week-old infant who developed fever, portal vein thrombosis and livedo reticularis like skin rash. Evaluation for thrombosis revealed high titers of antiphospholipid (aPL) antibodies (dual positive) in the child without any evidence of aPL antibodies in the mother, suggesting a de novo production in the child. Autopsy findings revealed umbilical vein sepsis with thrombosis of portal vein secondary to gram positive cocci which led to multiple liver and lung abscesses. Additionally, the baby had disseminated Cytomegalovirus (CMV) disease (acquired postnatally) involving walls of umbilical and portal vein, liver, lungs, adrenals, pancreas, thymus, and kidneys. Our case highlights the need for testing of aPL in every neonate with arterial or venous thrombosis even when the mother may have no features suggestive of an autoimmune disease.

Skin Manifestations Associated with COVID-19: Current Knowledge and Future Perspectives.

BACKGROUND: Coronavirus disease-19 (COVID-19) is an ongoing global pandemic caused by the "severe acute respiratory syndrome coronavirus 2" (SARS-CoV-2), which was isolated for the first time in Wuhan (China) in December 2019. Common symptoms include fever, cough, fatigue, dyspnea and hypogeusia/hyposmia. Among extrapulmonary signs associated with COVID-19, dermatological manifestations have been increasingly reported in the last few months. SUMMARY: The polymorphic nature of COVID-19-associated cutaneous manifestations led our group to propose a classification, which distinguishes the following six main clinical patterns: (i) urticarial rash, (ii) confluent erythematous/maculopapular/morbilliform rash, (iii) papulovesicular exanthem, (iv) chilblain-like acral pattern, (v) livedo reticularis/racemosa-like pattern, (vi) purpuric "vasculitic" pattern. This review summarizes the current knowledge on COVID-19-associated cutaneous manifestations, focusing on clinical features and therapeutic management of each category and attempting to give an overview of the hypothesized pathophysiological mechanisms of these conditions.

[Cutaneous alterations in vasculitides : Part 2: Special aspects of diseases of large, medium and small vessels]. / Hautveränderungen bei Vaskulitiden : Teil 2: Spezielle Aspekte der Krankheitsbilder großer, mittelgroßer und kleiner Gefäße.

Cutaneous vasculitides present with typical clinical signs depending on the size and distribution of the affected vessels. Since there are no large vessels in the skin, giant cell arteritis and Takayasu's arteritis only rarely lead to cutaneous symptoms. The classical systemic polyarteritis nodosa (PAN) is very rare. More frequent is cutaneous PAN presenting with a typical localized livedo racemosa and palpable subcutaneous nodules. The ANCA-associated vasculitides, which belong to the small vessel vasculitides, usually show systemic involvement and manifest on the skin with a diverse picture. Immune complex vasculitides are characterized by deposition of immunoglobulins on the walls of small vessels. The most common form is IgA vasculitis with the cardinal symptoms of palpable, round or oval and partially branched (retiform) purpura and a clear predilection for the legs. Serum disease is a príme example of systemic immune complex diseases due to large circulating immune complexes. Cryoglobulinemic vasculitis primarily involves small as well as medium sized vessels. Simultaneous involvement of vessels of different sizes is characteristic for vasculitis in systemic lupus erythematosus (SLE), Sjögren's syndrome, rheumatoid arthritis and sarcoidosis. Recurrent macular vasculitis in hypergammaglobulinemia is an episodic macular vasculitis of the small blood vessels. Bacteremic vasculitis of the small vessels (without direct microbial infection of the vessel wall) can typically also affect capillaries of dermal papillae and is usually accompanied by a disseminated intravascular coagulation (DIC). In some cases more than one distinct cutaneous vasculitis can occur in the same patient.