Claudio Comacchi

Cutaneous small-vessel vasculitis

Cutaneous small-vessel vasculitis (CSVV) refers to a group of disorders usually characterized by palpable purpura; it is caused by leukocytoclastic vasculitis of postcapillary venules. CSVV can be idiopathic or can be associated with a drug, infection, or underlying systemic disease. Initially, the pathogenesis of CSVV is immune complex related, but in its later stages different pathogenetic mechanisms may intensify the reaction and lymphocytes may predominate in the infiltrate. Cure requires elimination of the cause (ie, drugs, chemicals, infections, food allergens) when possible, as well as therapy with nonsteroidal antiinflammatory agents, corticosteroids, dapsone, potassium iodide, fibrinolytic agents, aminocaproic acid, immunosuppressive agents (ie, cyclophosphamide, azathioprine, methotrexate, cyclosporine) or even monoclonal antibodies, depending on disease severity.

Proposal for a working classification of cutaneous vasculitis

Vasculitis is defined as segmental angiocentric, leukocytoclastic (and/or lymphomonocytic) inflammation and fibrinoid necrosis of blood vessels.1–4 Involvement of arteries and, sometimes, venules and veins of various sizes and in different locations throughout the body is possible and results in a multiplicity of signs and symptoms.1–4 Vasculitis can be idiopathic or can be associated with a drug, infection, or underlying systemic disease.1–4 The marked variability in the clinical and histological features of the vasculitides and the numerous causes for these disorders have created confusion and prevented the development of a universally adopted classification scheme.1–4 Groundwork for many contemporary nosologic schemes was presented at the University of Texas Southwestern Medical Center by Gilliam and Smiley in 19765; since then many alternative classification systems have been proposed.6–12 The most recent classification scheme offered by the American College of Rheumatology (ACR) in 199012 groups vasculitis as follows:

Purpuras and related conditions

Abstract Purpuras include a wide spectrum of cutaneous disorders characterized by extravasation of red blood cells into the skin with consequent release of hemoglobin. Various other pigments deriving from heme are subsequently found into the skin within 2–3 weeks, accounting for the color changes (purple, orange, brown, yellowish, green-blue) which may occur in most purpuric lesions. Too often the factors leading to these disturbances are obscure. Sometimes they are obscure mainly to the dermato-venereologist as they are generally considered more pertinent to the field of interest of other specialists, i.e. in hematology or internal medicine. The dermato-venereologist should be familiar with these cutaneous conditions and, when necessary, cooperate with the hematologist in order to evaluate the cutaneous and extracutaneous signs and symptoms and to schedule the proper systemic and/or topical therapies. Learning objective. At the conclusion of this learning activity, participants should be able to discuss the clinical and histological presentations of purpuric disorders and know which tests should be done to allow proper diagnosis and treatment. The participants should also be aware of the controversies concerning the pathogenesis of some kinds of purpuras (i.e. palpable purpuras), of the evolution of terminology and finally of the different therapeutic options and regimens.

Mesoglycan treatment restores defective fibrinolytic potential in cutaneous necrotizing venulitis

Background. Cutaneous necrotizing venulitis (CNV) is a clinical disorder associated with segmental inflammation and fibrinoid necrosis of the dermal venules. It usually presents clinically as palpable purpura, even sometimes as nodules, bullae, ulcers, and urticarial lesions. This form, when showing as leukocytoclastic vasculitis is apparently characterized by the tissue deposition of circulating immune complexes and by reduced cutaneous (cfa) and plasma (pfa) fibrinolytic activity due to reduced release of plasminogen activator (PA) from the venular endotheliocytes. Reduced cfa and pfa cause large amounts of fibrin deposits in both intra‐ and perivascular areas, which are able to magnify and self perpetuate the inflammatory processes following immune complex deposition.

γ/δ T lymphocytes and infection: pathogenesis of leukocytoclastic cutaneous necrotizing vasculitis

Many factors, especially drugs (insulin, penicillin, sulfonamides), chemicals (insecticides, petroleum products), food (milk protein), and infections (viral, fungal, bacterial, protozoan), are considered causes of cutaneous necrotizing vasculitis (CNV)1–6 (Table 1). In addition, CNV has been reported in association with other diseases (i.e., collagen-vascular diseases, hyperglobulinemic purpura, cryoglobulinemia, inflammatory bowel disease, malignant neoplasm, cystic fibrosis, and others) (Table 2). In many cases the cause of CNV remains unknown (i.e., Schoenlein-Henoch purpura, urticarial vasculitis, erythema elevatum diutinium, nodular vasculitis, livedoid vasculitis, atrophie blanche, cutaneous polyarteritis nodosa).1–6 On the basis of histopathological features, two major forms of CNV are recognized independently of the etiology: a leukocytoclastic form, of presumed immunecomplexes-mediated pathogenesis, and a lymphomonocytic form of presumed immune cell-mediated pathogenesis.1–6 Immunofluorescent studies generally show perivascular IgG or IgM complement and fibrin deposits and hypocomplementemia in leukocytoclastic vasculitis, while immunofluorescence is not contributory in lymphomonocytic vasculitis. Usually the infiltrate progressively changes from a preponderance of neutrophilis to a predominance of lymphocytes, suggesting the dynamic nature of the vasculitic process and supporting the participation of a secondary cell-mediated immune response also in the late phase of the leukocytoclastic form of CNV.1–6 Both the histopathological and immunopathological data do not provide any information about the etiology of vasculitis. Conversely, it is extremely important to document or to exclude a possible infective etiology because the therapeutic approach may greatly change.1–6 g/d T Lymphocytes: An Emerging Cell in Infective Skin Disorders

TREATMENT PEARLS FROM EUROPE

Discussing the need for psychological treatment of a dermatological condition with children and families can be a daunting task. Families must be given accurate information about the role of psychological or behavioral factors in the exacerbation or maintenance of their childs condition; however, this information must be presented in a way that families and children do not feel criticized or judged. This article discusses nondrug treatments of skin diseases.

Langerhans’ cells and cutaneous necrotizing vasculitis

The cutaneous cells bearing Paul Langerhans’ eponym were first described by him in 1868.1 Langerhans used the gold chloride impregnation method to identify these cells, which he believed played a role in transducing external stimuli to the nervous system. These cells have remained mysterious for a very long time; as late as 1974, Montagna and Parakkal could state that “their origin remains somewhat obscure and their function is completely unknown.”2