Severe spontaneous arterial thrombotic manifestations in patients with inherited hypo‐ and afibrinogenemia

Summary.  We report two novel cases of severe arterial thrombotic episodes occurring in two women with severe hypofibrinogenemia, not linked to the administration of replacement therapy. The first patient had sudden acute occlusion of the anterior branch of left renal artery with infarction of the antero‐lateral region of the upper part of the left kidney during treatment with combined oestrogen‐progestogen started 16 years before for recurrent haemoperitoneum caused by bleeding at ovulation. The second patient showed recurrent arterial thrombosis of lower limbs over 2 years, which eventually led to amputation of affected limbs. Thrombotic events in patients with inherited severe hypofibrinogenemia are rather frequent, may be severe and not associated with the use of replacement therapy.