Afibrinogenemia and hypofibrinogenemia (in its isolated type; not associated with dysfibrinogenemia) are congenital quantitative abnormalities of fibrinogen. They expose patients to a bleeding risk of variable severity depending on their phenotype. Thrombotic complications, however, have been reported in the literature in isolated cases. These cases were venous [
1] or arterial thromboses and most occurred after administration of cryoprecipitates or fibrinogen. Nevertheless, some cases of spontaneous arterial thrombotic events have been reported (Table
1). The majority of them concerned peripheral arteries in patients with afibrinogenemia (where fibrinogen levels are lower than those in patients with hypofibrinogenemia, leading to a more significant rise in the circulating thrombin, but it muct be noted that afibrinogenemia also has a greater prevalence). To the best of our knowledge, only a single case of myocardial infarction has previously been reported, in a 27-year-old male patient with afibrinogenemia [
2]. In our patient, in addition to the typical clinical, ECG and biological features which were coherent with the definition of acute myocardial infarction, the diagnosis was further confirmed by MRI. Nevertheless, the coronary thrombosis was not viewed by a coronary computed tomography angiography (which was unavailable) or by invasive explorations, which were problematic in view of the hemorrhagic risk. For the patient described by Kumar
et al. [
2], who was admitted two hours after pain onset, as well as for our patient, who was admitted seven hours after pain onset, the risk of bleeding that accompanies coronary angioplasty (and its adjunctive anticoagulant therapy) seemed to outweigh the expected benefit and it was therefore not indicated in either case. Also, because of the precarious balance of the process of hemostasis, thrombolytics and anti-thrombotic treatments could not be used. The use of these treatments classically contraindicated in fibrinogen deficient patients has nevertheless been described in cases of thrombotic complications, often in parallel with fibrinogen infusion [
3‐
5,
10].
Table 1
Cases of arterial spontaneous thrombotic complications in patients with fibrinogen deficiency reported in the literature
| 33 M | Afibrinogenemia | Iliac artery thrombosis and toe necrosis |
| 37 F | Afibrinogenemia | Ischemic necrosis of the first left toe |
| 37 F | Afibrinogenemia | Bilateral distal ischemia of fingers and toes |
| 14 F | Afibrinogenemia | Ischemic necrosis of the right foot due to popliteal artery thrombosis |
| 30 M | Afibrinogenemia | Ischemic lesions of the feet secondary to an occlusive lesion of the hypogastric artery and highly stenotic lesions of the iliac arteries (two episodes at three-year interval). After surgical bypass, asymptomatic occlusion of the bypass occurred at Day three. |
| 22 M | Afibrinogenemia | Ischemic stroke in a context of aortic marastic endocarditis |
| 21 F | Afibrinogenemia | Ischemia of the fifth toe then of the fourth toe |
| 27 M | Afibrinogenemia | Inferior acute myocardial infarction |
| 35 F | Hypofibrinogenemia | Renal infarction |
| 60 F | Hypofibrinogenemia | Toe ischemia by bilateral thrombosis of the anterior tibial arteries |
The increased risk of thrombosis in cases of fibrinogen deficiency could be explained by a rise in the level of circulating thrombin which is no longer inactivated by fibrin (previously known as antithrombin I factor) [
3,
10]. The thrombin, playing the role of platelet activator, favors the excretion of Von Willebrand factor from platelet alpha-granules. This later enhances platelet aggregation by binding to glycoprotein IIb/IIIa, leading to the formation of loose large thrombi [
3]. Concerning the pathophysiologic mechanism, antiaggregant treatments can be effective in preventing the genesis of thrombotic events. Our patient received only aspirin; the patient described by Kumar
et al. [
2] received dual antiplatelet therapy (aspirin and clopidogrel). Neither of these two patients had an ischemic recurrence or a hemorrhagic complication.