Thrombophilic risk of individuals with rare compound factor V Leiden and prothrombin G20210A polymorphisms: an international case series of 100 individuals.

The risk of thrombosis in individuals with rare compound thrombophilias, homozygous factor V Leiden (FVL) plus heterozygous prothrombin G20210A (PTM), homozygous PTM plus heterozygous FVL, and homozygous FVL plus homozygous PTM, is unknown. We identified, worldwide, individuals with these compound thrombophilias, predominantly through mailing members of the International Society on Thrombosis and Haemostasis. Physicians were sent a clinical questionnaire. Confirmatory copies of the genetic results were obtained. One hundred individuals were enrolled; 58% were female. Seventy-one individuals had a venous thrombosis (includes superficial and deep vein thrombosis, and pulmonary embolism), 4 had an arterial thrombosis and 6 had both. Nineteen individuals had never had a thrombotic event. Thrombosis-free survival curves demonstrated that 50% of individuals had experienced a thrombotic event by 35 yrs of age, while 50% had a first venous thromboembolic event (VTE; includes all venous thrombosis except superficial thrombosis) by 41 yrs of age; 38.2% of first VTEs were unprovoked. 37% of patients had at least one VTE recurrence. Seventy percent of first pregnancies carried to term and not treated with anticoagulation were thrombosis-free. In conclusion, patients with these rare compound thrombophilias are not exceedingly thrombogenic, even though they have a substantial risk for VTE.

Lim MY ，Deal AM ，Kim S ，Musty MD ，Conard J ，Simioni P ，Dutrillaux F ，Eid SS ，Middeldorp S ，Halbmayer WM ，Boneu B ，Moia M ，Moll S ... -  《-》

High risk of thrombosis recurrence in patients with homozygous and compound heterozygous factor V R506Q (Factor V Leiden) and prothrombin G20210A.

Heterozygous Factor V R506Q [Factor V Leiden (FVL)] and prothrombin G20210A (PGM), the most common inherited thrombotic disorders in the Caucasian population, confer a low-moderate risk for first venous thromboembolic (VTE) event. We investigated the thrombotic complications of rare homozygous and compound heterozygous FVL and PGM. A cohort of patients with homozygous and compound heterozygous FVL and PGM were evaluated at a major referral center in Central Pennsylvania, USA between June 2001 and March 2019. Data including incidence of first and recurrent thrombosis, associated risk factors, family history and demographics were collected. Seventy-five patients were eligible for analysis: 47 had homozygous FVL, three had homozygous PGM, 19 had compound heterozygous FVL and PGM, five had compound homozygous FVL and heterozygous PGM, and one had compound heterozygous FVL and homozygous PGM. Fifty-nine patients experienced 111 thromboembolic events. Forty-seven percent of first thrombotic events occurred in patients without clinical or surgical conditions predisposing to thrombosis. The rate of recurrent thromboembolism was 59%. The mean time to recurrence was 8.5 years. Ninety percent of recurrent events occurred during times when patients were not treated with anticoagulation. Persons with homozygous and compound heterozygous FVL and PGM are at a significantly increased risk of first unprovoked and recurrent VTE. Patients with first thromboembolic events should be considered for long-term anticoagulation.

Federici EH ，Al-Mondhiry H 《-》

Risk of recurrent venous thrombosis in homozygous carriers and double heterozygous carriers of factor V Leiden and prothrombin G20210A.

Lijfering WM ，Middeldorp S ，Veeger NJ ，Hamulyák K ，Prins MH ，Büller HR ，van der Meer J ... -  《-》

The risk of recurrent venous thromboembolism among heterozygous carriers of factor V Leiden or prothrombin G20210A mutation. A systematic review of prospective studies.

Marchiori A ，Mosena L ，Prins MH ，Prandoni P ... -  《-》

Type and location of venous thromboembolism in carriers of Factor V Leiden or prothrombin G20210A mutation versus patients with no mutation.

Kovac M ，Mitic G ，Mikovic Z ，Antonijevic N ，Djordjevic V ，Mikovic D ，Mandic V ，Rakicevic L ，Radojkovic D ... -  《-》