**3.3 Factors C and S**

The conclusion from the analysis of patients with factor C and S deficiency is limited by the lack of sufficient data to make specific recommendations, but it is safe to approach these patients from the point of view of venous thromboembolism management [10, 29].

Treatment of the first episode of venous thromboembolism should consist of unfractionated or LMWH for at least 5 days followed by vitamin k antagonists or DOAC for at least 3–6 months. In the presence of other clotting disorders or risk factors for thrombosis, or if the first episode was life-threatening or occurred in multiple sites, anticoagulation may be prolonged indefinitely [13].
