Background and objective: We aimed to determine the risk factors of thromboembolic disease in young patients and to study the clinical characteristics according to the etiology.
Patients and method: A prospective study of 100 patients under 50 years who were not affected by neoplasias or chronic diseases and who required hospitalization due to thromboembolic disease. The morphological diagnosis was performed by eco-Doppler, flebography, lung gammagraphy or CT scan. Risk factors assessed were antithrombin, protein C and S deficiency, presence of factor V Leiden, prothrombin G20210A, hyperhomocisteinemia, increased PAI-I, increased factor VIII, and presence of antiphospholipid antibodies (APAs). Acquired factors were also evaluated.
Results: In 87% of patients, a venous thrombosis was observed in lower limbs. 37% of patients had congenital risk factors and 19% had APAs, whereas in the remaining patients only acquired factors were demonstrated. Most frequent congenital factors were factor V Leiden, pothrombin G20210A, and protein C and S deficiency. Most patients presented several risk factors. A family thrombotic history was significantly more frequent in the group with congenital risk factors.
Conclusions: In 56% of young patients with thromboembolic disease, a congenital etiology or APAs are identified. In these patients the number of acquired factors needed to trigger thrombosis is fewer than in patients in whom a cause is not identified.