[Fibrinolytic system and a central retinal vein thrombosis]

On the basis of literature review the role of fibrinolysis in the pathogenesis of central retinal vein thrombosis is presented. It has been proved by many authors that fibrinolytic activity is depressed in patients with vascular thrombosis, due to increased levels of fibrinolytic inhibitors mainly plasminogen activator inhibitor (PAI 1), and/or decreased levels of tissue plasmogen activator (t-PA). Low levels of t-PA and increased levels of PAI-1 have been found in states of special risk of thrombosis: obesity, diabetes mellitus, postoperative states, rheumatoid arthritis, malignancies and other diseases such as Behcet's syndrome. In pregnancy susceptibility to thrombosis follows the presence in blood of PAI-2, an inhibitor of plasminogen activators secreted by the placenta. Therapy is based on the use of anticoagulants (e.g. heparin) and thrombolytic agents (e.g. streptokinase).