Retiform purpura: Workup and therapeutic considerations in select conditions

Annular vasculitic lesions

Vasculitic skin findings may present with annular morphologies. This group of conditions consists of capillaritis, such as pigmented purpuric dermatoses, and vasculitis, which is often classified by the affected vessel size. Annular vasculitic lesions may be the presenting sign of systemic disease, thus requiring thorough exploration to reach an accurate diagnosis and guide proper disease management. Herein we review the clinical presentation, histopathology, and treatments for cutaneous vasculitic disease that may present with annular lesions.

Clinical analysis of skin lesions in livedoid vasculopathy: a study of 46 Chinese patients

BACKGROUND

Clinical data regarding cutaneous manifestations in Chinese patients with livedoid vasculopathy (LV) are limited.

OBJECTIVES

To assess clinical features of skin lesions in LV, especially the characteristics of extensive livedo reticularis and pigmented purpuric dermatosis-like lesions in these patients.

METHODS

This was a single-center retrospective study of 46 Chinese patients with LV between March 2021 and July 2021. The characteristics of skin lesions in LV were described in detail.

RESULTS

A total of 29 females and 17 males were included in this study, with a mean age of 27.7 years (ranging from 13 to 51 years). Twenty (43.5%) patients developed their first skin lesions before age 18. Among 46 patients, 33 presented livedo reticularis with 78.8% (n = 26) of these patients whose livedo reticularis was extensive. Seven patients had lesions simulating pigmented purpuric dermatosis, including four cases of pigmented purpura and three cases of telangiectatic purpura. Numbness was found in 16 patients, mainly in the lower limbs (62.5%), ankles (31.3%), and dorsum of the feet (18.8%).

CONCLUSIONS

For patients with symptoms of extensive livedo reticularis, retiform purpura, or numbness, it is necessary to make a differential diagnosis.

Levamisole-induced and COVID-19-induced retiform purpura: two overlapping, emerging clinical syndromes

Levamisole exposure in cocaine users is a well-recognized cause of retiform purpura, a distinctive net-like maculopapular patch. Prolonged exposure to levamisole can lead to a serious systemic syndrome known as levamisole-induced vasculitis, most commonly involving the kidneys and lungs. More recently, retiform purpura has been observed in patients with the novel coronavirus disease of 2019 (COVID-19). Due to their overlapping dermatologic and systemic manifestations, levamisole-induced and COVID-19-induced retiform purpura may mimic one another in clinical presentation. The possibility that patients may present with one or both syndromes creates a diagnostic challenge. This review of levamisole-induced and COVID-19-induced retiform purpura highlights their corresponding and distinctive features. Additionally, we propose a unique staging system for levamisole-induced retiform purpura that may be valid for future classification of COVID-19-induced retiform purpura.

Livedoid vasculopathy - A diagnostic and therapeutic challenge

Livedoid vasculopathy is a rare, chronic-recurrent occlusive disorder in the microcirculation of dermal vessels. The clinical appearance is characterized by Livedo racemosa, painful ulceration, located in the distal parts of the lower extremities, followed by healing as porcelain-white, atrophic scars, the so-called Atrophie blanche. Different conditions that can promote a hypercoagulable state, such as inherited and acquired thrombophilias, autoimmune connective-tissue diseases and neoplasms, can be associated with livedoid vasculopathy. Therefore, livedoid vasculopathy is currently considered to be a coagulation disorder, clearly distinguished from inflammatory vasculitis. Although there are hints to hypercoaguability and secondary inflammation, pathophysiology is not completely understood. Diagnosis is made by synopsis of history, clinical and histopathological findings. Early and adequate therapy is essential to maintain life quality and avoid irreversible complications. Better understanding of molecular mechanisms is required to establish appropriate therapy regimens. This article presents the current state of knowledge about livedoid vasculopathy and proposes an algorithmic approach for diagnosis and therapy.

Revisiting the question of cutaneous vasculitis classification

Currently, there is no generally accepted terminology and classification of vasculitis and vascular cutaneous disorders. In Russia there are various approaches to the classification of cutaneous vasculitis vascular lesions are classified according to clinical signs, etiology and pathogenesis. Significant difficulties are caused by the lack of a unified terminology, clear diagnostic criteria for vasculitis and the existence of a large number of duplicate names, among which there are many eponymous terms. This issue is one of the most complex, confusing and debatable not only in dermatovenereology, but also in other disciplines. Modern principles of diagnosis of cutaneous vasculitis are based on an integrated assessment of the data of the disease history, clinical picture, laboratory and instrumental methods of examination. For standardization of definitions and diagnostic criteria, it is necessary, first of all, to adopt a unified interdisciplinary classification of vasculitis, which will be based on the etiopathogenetic principle. The applied unified classification of cutaneous vasculitis is proposed for discussion.

Eosinophilic granulomatosis with polyangiitis: Cutaneous clinical and histopathologic differential diagnosis

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare, but severe systemic vasculitis that can affect skin and other organ systems. Diagnostic criteria have evolved, and many attempts have been made to classify the vasculitides based on clinical and/or histopathologic features, with an aim to develop standardized criteria. According to the EGPA Consensus Task Force recommendations, EGPA is a syndrome of asthma, eosinophilia, pulmonary infiltrates, and extrapulmonary vasculitis (such as cutaneous involvement with purpura). Histopathologic evidence of vasculitis in EGPA may be associated with eosinophilic infiltration and/or perivascular granulomatous inflammation. We review clinicopathologic criteria of this enigmatic vasculopathy.

Mimics of vasculitis

While prompt diagnosis of vasculitis is important, recognition of vasculitis mimics is equally essential. As in the case of vasculitis, an approach to mimics based on the anatomic size of vessels can be useful. Infections can mimic vasculitis of any vessel size, including the formation of aneurysms and induction of ANCAs. Genetic disorders and vasculopathies are important considerations in large and medium vessel vasculitis. Cholesterol emboli, thrombotic conditions and calciphylaxis typically affect the medium and small vessels and, like vasculitis, can cause cutaneous, renal and CNS manifestations. Reversible cerebral vasoconstriction syndrome is important to distinguish from primary angiitis of the CNS. As an incorrect diagnosis of vasculitis can result in harmful consequences, it is imperative that the evaluation of suspected vasculitis includes consideration of mimics. We discuss the above mimics and outline a systematic and practical approach for differentiating vasculitis from its mimics.

[Acute fever with rash, necrosis, and bullae in both lower extremities in a 12-year-old girl]

A girl, aged 12 years, was admitted due to fever and rash for 3 days. The child developed recurrent high fever and rash on both lower extremities 3 days before, and the rash on left lower extremity quickly merged into a patch within 24 hours, with hemorrhage and necrosis in black and purple, large vesicles, and blisters in the center. Laboratory examination showed a reduction in platelet count and significant increases in fibrinogen and D-dimer during the course of the disease. The child was diagnosed with purpura flulminans. She was given meropenem combined with linezolid for anti-infection, injection of gamma globulin for immunoregulation, and low-molecular-weight heparin for anticoagulation. The fluid in the rash blisters was drawn and the wound was treated to prevent infection. The child's temperature returned to normal, with improvement in gangrene. She was discharged after platelet count, fibrinogen, and D-dimer had returned to normal. Purpura fulminans is a rare thrombotic hemorrhagic disease with rapid progression and is commonly seen in children. Without timely treatment, it may cause severe sequelae with high disability and mortality rates. Anti-infection, correction of coagulation function, and local management of gangrene skin are of great importance during treatment.