Abstract Number: PB2242
Meeting: ISTH 2020 Congress
Theme: Venous Thromboembolism and Cardioembolism » Thrombophilia
Background: Congenital dysfibrinogenemia (CD) is a rare autosomal dominant disorder characterized by normal levels of circulating fibrinogen with low functional activity due to missense mutations in one of the fibrinogen genes. The majority of these patients remain asymptomatic; however, the estimated cumulative incidence of thrombosis at age 50 years is 30%.
Aims: To describe a patient with CD diagnosed after 2 major episodes of venous thrombosis.
Methods: Retrospective review of electronic medical records to describe the clinical manifestations and diagnostic evaluation.
Results: 44-year-old Asian man presented after a fall with loss of consciousness, and was diagnosed with a large cerebral venous sinus thrombosis (Figure 1). He received unfractionated heparin and was discharged on warfarin, which he continued for 1 year.
Two years after stopping anticoagulation, he developed massive left leg swelling and cyanotic discoloration after running a marathon. A compression ultrasound showed extensive common and external iliac vein thrombosis. He received tissue-plasminogen activator and a venous stent. His initial coagulation tests are listed on Table 1. Post-procedure fibrinogen was < 50 mg/dL and he received 3 units of cryoprecipitate. He was discharged on rivaroxaban 20 mg daily. There was no family history of thrombosis or bleeding disorders. Thrombophilia screening was negative (Table 1). Fibrinogen activity repeated 6 months after was 53 mg/dL and was verified one month later. He had prolonged thrombin time (TT) and his fibrinogen antigen was normal. Based on these results he was diagnosed with dysfibrinogenemia. Genotyping revealed FGG missense mutation of c.901C>T. Patient has remained on rivaroxaban 10 mg daily with no recurrent thrombosis or bleeding events.
Patient’s asymptomatic mother was tested and she was also found to have dysfibrinogenemia (Table 1). Genotyping is in progress.
Conclusions: CD should be considered in young patients presenting with unprovoked recurrent major venous thrombosis even in the absence of a positive family history.
[(A) MRV showing limited flow in the middle third superior sagittal sinus. (B) Brain MRI showing T1 hyperintense thrombus.]
| Laboratory Tests | Patient | Mother (**tests done while on apixaban for atrial fibrillation) |
| PT (sec) | 13.9 (normal 9.7 – 12.8) | 17.0 (normal 10.2 – 12.6) |
| aPTT (sec) | 30.8 | 34.8 |
| TT (sec) | 61.0 | 70.6 |
| Reptilase time (sec) | N/A | 47.0 |
| Fibrinogen, activity (mg/dL) | < 50 | 62 |
| Fibrinogen, antigen (mg/dL) | 304 | 381 |
| Thrombophilia Testing | Antithrombin level normal; Protein C and Protein S activities normal; Lupus anticoagulant negative; Cardiolipin antibodies and Anti-β2 glycoprotein antibodies negative; Activated Protein C resistance normal; Homocysteine level normal; PNH screen negative; JAK2 V617F negative; CALR negative; Factor VIII level normal; Factor IX level normal; Factor XI level normal | N/A |
[Results of Laboratory Tests in Patient and His Mother]
To cite this abstract in AMA style:
Lim HI, DeSancho MT. Venous Thrombosis-dominant Congenital Dysfibrinogenemia Presenting with Cerebral Venous Sinus Thrombosis [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/venous-thrombosis-dominant-congenital-dysfibrinogenemia-presenting-with-cerebral-venous-sinus-thrombosis/. Accessed December 11, 2023.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/venous-thrombosis-dominant-congenital-dysfibrinogenemia-presenting-with-cerebral-venous-sinus-thrombosis/