Ischemic stroke is associated with leucocyte activation. Activated leucocytes release elastase, an enzyme that can degrade fibrinogen. Fibrinogen elastase degradation products (FgEDP) may serve as a specific marker of elastase proteolytic activity. In a case-control study of 111 ischemic stroke patients and 119 controls, significantly higher FgEDP levels were observed in cases than in controls, both in the acute phase and in the convalescent phase. Results were only slightly affected by adjustment for cardiovascular risk factors, C-reactive protein and fibrinogen. Our findings suggest that FgEDP might be involved in the pathogenesis of stroke.