Biomedical subjects
Publications and source records attributed to C Comacchi.
Explore the source record for details and available documents.
Cutaneous necrotizing vasculitis (CNV) is a complex multisystem disease generally involving the skin and mucous membranes, often accompanied by renal, gastrointestinal, pericardial, neurological, and articular signs and symptoms. CNV may be idiopatical or occur in association with a drug, infection, or underlying disease. CNV has been shown in patients with chronic infections (viral, bacterial, protozoa, helminthic), serum sickness, a variety of collagen vascular diseases (systemic lupus erythematous, Sjögren's syndrome, rheumatoid arthritis, Behçet's disease) hyperglobulinemic states, cryoglobulinemia, bowel bypass syndrome, ulcerative colitis, cystic fibrosis, primary biliary cirrhosis and HIV infection. Association with malignancies is not frequent. Lymphoproliferative disorders (Hodgkin's disease, mycosis fungoides, lymphosarcoma, adult T-cell leukemia, multiple mieloma) and solid tumors (lung cancer, colon carcinoma, renal, prostate, head and neck cancer and breast cancer) may be associated with CNV. Whenever possible, treatment is directed at the elimination of the cause. In other cases after adequate laboratory screening local and systemic therapy are recommended.
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.
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 child's 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.
Explore the source record for details and available documents.
BACKGROUND: Progressive pigmented purpura (Schamberg's disease), a form of purpura pigmentosa chronica, is a lymphocytic capillaritis of unknown etiology and obscure pathogenesis. Our purpose was to assess the expression of cell membrane antigens (CD3, CD4, CD1a, CD36), of adhesion receptors (leukocyte function adhesion 1, LFA-1, endothelial leukocyte adhesion molecule 1, ELAM-1) intercellular adhesion molecule 1, ICAM-1), and the intercellular relationships in the early phase of the disease. METHODS: Quantitative immunohistochemistry and electron-microscopy were performed on specimens of five subjects, aged 45 to 63 years. These studies were repeated in two patients after treatment with topical corticosteroid (betamethasone valerate cream 0.1%) and psoralen-ultraviolet A (PUVA). RESULTS: The infiltrate consisted mainly of CD4+ lymphocytes and CD1a+ dendritic cells. Electron-microscopic investigation showed typical lymphocytes and two distinct types of dendritic cells. In the very early phase of the disease the adhesion receptors LFA-1 and ICAM-1 were expressed intensely by all infiltrating cells; the adhesion receptors ICAM-1 and ELAM-1 were expressed by endothelial cells. Close contact occurred between lymphocytes and dendritic cells. After PUVA (120 J per cm2) and topical steroid therapy the infiltrate disappeared completely. CONCLUSIONS: These data suggest that a cell-mediated immune mechanism may be important in progressive pigmented purpura and that the early endothelial expression of adhesion receptors may determine the pattern of organization of the pericapillary infiltrate.
Sections of lesional skin of 5 patients with leukocytoclastic cutaneous necrotizing vasculitis (CNV) (3 with documented infective etiology and 2 with unknow etiology) and of 5 patients with lymphocytic CNV with unknow etiology were investigated with immunoperoxidase technique. In lymphocytic CNV the dermal infiltrate was mainly constituted of CD3+, CD4+, CD1a+ and CD36+ cells. ICAM-1 and LFA-1 were strongly expressed. In leukocytoclastic CNV the infiltrate was poor of these cells in the early phase of disease, but they increased in the late phase. ICAM-1 and LFA-1 were strongly expressed in the late phase, while gamma/delta T cells and the expression of 72 kD heat shock protein were significantly present only in leukocytoclastic CNV with documented infective etiology. These results seem to suggest the role of a secondary cell-mediated immune response in the late phase of leukocytoclastic CNV, indicating gamma/delta T cells as a possible clue to the infective etiology of CNV.
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. METHODS: We have studied both the PFA and CFA potential (the maximum amount of PA released in the skin after certain stimuli) and the deposits of immunoglobulins, C3, and fibrin related antigen, before and after intradermal injection of histamine (a substance able to provoke endothelial release of PA), in three subjects affected by CNV before and 20 days after 10 mg/kg/day I.M. treatment with the fibrinolytic agent mesoglycan. RESULTS: Cutaneous fibrinolytic activity and CFA potential, reduced prior to treatment, was normal after treatment, while the deposits of immunoglobulins (IgA, IgG and IgM), C3, and fibrin related antigen, detected with direct immune fluorescence (DIF) showed similar findings before and after treatment. CONCLUSIONS: These data suggest that reduced CFA may play a major role in the pathogenesis of the immunologically mediated injury in CNV. The intraperivascular deposition of fibrin is favored. The fibrinolytic agent mesoglycan seems effective in restoring defective fibrinolysis in patients affected by cutaneous necrotizing venulitis, suggesting that in cases with reduced cutaneous fibrinolytic activity (or potential) the use of a fibrinolytic agent should be considered.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.