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Congenital afibrinogenemia is a rare coagulation deficiency characterized by the complete absence of fibrinogen. Most mutations are null mutations affecting synthesis, intracellular assembly, or fibrinogen secretion. Bleeding is the main symptom, often taking place as early as the neonatal period, with bleeding from the umbilical cord. The bleeding phenotype is severe, and is characterized by frequent muscle hematomas, hemarthroses, or brain bleeds. Paradoxically, patients with afibrinogenemia also suffer from thrombotic events. Both the arteries and veins are involved, suggesting a common physiopathology. Other symptoms, such as bone cysts, delayed wound healing, or spontaneous spleen ruptures have been observed and affect the patient’s health-related quality of life. Several fibrinogen concentrates are available, with similar pharmacokinetic properties, efficacy, and safety profiles. In cases of bleeding, fibrinogen supplementation is determined by the severity and the source of bleeding, with the aim being a fibrinogen level of 1–1.5g/L. The management of a thrombotic event is challenging as it requires the introduction of a fibrinogen prophylaxis together with antithrombotic therapy. Pregnancy and delivery are high-risk clinical situations. A multidisciplinary approach and an increasing fibrinogen supplementation throughout the pregnancy is mandatory.