Background <p>The prevalence of dysfibrinogenemia among patients with venous or arterial thrombosis is very low, so it is not commonly included in a diagnostic process. We present a rare case of recurrent arterial thrombosis in two different vascular beds in a young woman without any clear recognized risk factor, followed up for over a ten-year period.</p> Case presentation <p>A 21-year-old woman without comorbidities or known risk factors was diagnosed with acute lower limb ischemia due to massive arterial thrombosis. Despite successful targeted fibrinolysis, early reocclusion occurred, requiring surgical embolectomy. One month later, intracranial internal carotid artery occlusion and stenosis of the middle cerebral artery occurred. Basic laboratory tests for thrombophilia and echocardiography revealed no abnormalities. Expanded fibrin properties assessment showed reduced clot permeability and density, prolonged clot lysis time, increased maximum concentration with decreased maximum rate of D-dimer, accompanied by increased fibrin gel absorbance and shortened lag phase. Anticoagulant therapy was initiated with acetylsalicylic acid (75 mg daily) and acenocoumarol. After 6 years, acenocoumarol was replaced with rivaroxaban (15 mg daily). One year later, the patient became pregnant, and her antithrombotic regimen was changed to low-molecular-weight heparin (60 mg daily) combined with aspirin (75 mg daily). Following an uncomplicated vaginal delivery, rivaroxaban (15 mg daily) and aspirin were resumed. During the 10-year follow-up, no further thrombotic events were observed. </p> Conclusions <p>This case shows the importance of thorough and accurate diagnosis in patients with unprovoked atypical arterial thrombosis. Optimal therapy, including both invasive and conservative treatment, is needed, increasing the probability of successful outcomes, even when additional risk factors as pregnancy appear.</p> Clinical trial number <p>Not applicable.</p>