Cutaneous fibrinolytic potential, tPA dependent, is reduced in Behçet's disease

Immunopathogenesis of Behçet Disease

BACKGROUND

Behçet's Disease (BD, OMIM 109650) is a chronic relapsing inflammatory disease of unknown etiology with unpredictable exacerbations and remissions. First described in 1937 by the Turkish dermatologist HulusiBehçet, as a trisympton complex (oral and genital ulcers and uveitis), it is now recognized as a multisystemic disease. The syndrome can manifest in diverse ways and can involve nearly every organ system. Several studies have implicated T cells and monocytes in the pathogenesis of BD especially when these cells are stimulated by heat shock proteins and streptococcal antigen. This article presents a review of the relevant published literature about the immunopathogenesis of BD.

RESULT

The authors used MeSH terms "Behçet's disease" with "pathophysiology," "pathogenesis," "genetic", "epigenetic", "immunogenetic" or "immune response" to search the PubMed database. All the relevant studies identified were included.

Behçet disease: New aspects

Behçet disease is currently considered an "autoinflammatory disease" triggered by infection and environmental factors in genetically predisposed individuals. Although the disease is characterized by recurrent oral and genital aphthous ulcers and ocular involvement, it can affect multiple organ systems. Complex aphthosis is characterized by recurrent oral and/or genital aphthous ulcers. It is important to evaluate the patient with complex aphthosis for Behçet disease and related systemic disorders. We discuss the etiopathogenesis, clinical features, diagnostic criteria, and treatment approaches for complex aphthosis and Behçet disease in light of the current literature.

The multiple faces of Behçet's disease and its aetiological factors

Behçet's disease (BD) is a chronic, inflammatory multisystemic condition of unknown aetiology. It is clinically characterized by recurrent orogenital ulcerations and skin eruptions; ocular manifestations; arthritis; vasculitis and in some cases neurological and large vessel involvement. Aetiology has not been defined, but genetic, environmental, viral, bacterial and immunological factors have been proposed as causative agents. Treatment includes colchicine, thalidomide, steroids and immunosuppressive agents and it is based on the severity of systemic manifestations, such as central nervous system involvement, arterial aneurysms and thrombosis of the major veins. Mortality is related to major system involvement. In this article the different clinical features, the multiple faces of BD and a list of currently suspected aetiological factors of the disease are discussed, and treatment modalities summarized.

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.

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.