Prothrombin G20210A Research Articles

Thrombophilia genetic mutations and their relation to disease severity among patients with COVID-19.

Patients with COVID-19 infection appear to develop virus-induced hypercoagulability resulting in numerous thrombotic events. The aim of the present study was to determine the relationship between the thrombophilia genes mutations (prothrombin G20210A, factor V Leiden, and methyltetrahydrofolate reductase (MTHFR)) and the severity of COVID-19 patients. Prospective cross-sectional study. One hundred and forty patients (80 adults and 60 children) were included in the current study. They were divided into the severe COVID-19 group and the mild COVID-19 group, with each group comprising 40 adults and 30 children. The patients were assessed for FV R506Q, FV R2H1299R, MTHFR A1298C, MTHFR C677T, and prothrombin gene G20210A polymorphisms. CBC, D-dimer, renal and liver function tests, hs-CRP, ferritin, and LDH were also assessed. Thrombotic events were clinically and radiologically documented. Severe COVID-19 cases were significantly more frequent to have a heterozygous mutation for all the studied genes compared to mild COVID-19 cases (p<0.05 for all). Being mutant to gene FV R506Q carried the highest risk of developing a severe disease course (p<0.0001). Patients with abnormally high D-dimer levels were significantly more frequent to be heterozygous for FV R506Q, FV R2H1299R, and prothrombin gene G20210A (p = 0.006, 0.007, and 0.02, respectively). We concluded that there is an evident relationship between severe COVID-19 and inherited thrombophilia. In the current study, FV R506Q gene mutation carried the highest risk of developing a severe COVID-19 disease course.

Study of prevalence of thrombophilic genes (FVL G1691A, prothrombin G20210A and MTHFR C677T) polymorphisms in patients with venous thromboembolism in Benha university hospital; cross sectional study.

Study of prevalence of thrombophilic genes (FVL G1691A, prothrombin G20210A and MTHFR C677T) polymorphisms in patients with venous thromboembolism in Benha university hospital; cross sectional study.

Outcomes of venous thromboembolism in patients with inherited thrombophilia treated with direct oral anticoagulants: insights from the RIETE registry.

While direct oral anticoagulants (DOACs) are frequently used to treat venous thromboembolism (VTE), the outcomes of patients with inherited thrombophilia (IT) receiving DOACs for VTE remain understudied. We used data from the international RIETE registry to compare the rates of VTE recurrences, major bleeding, and mortality during anticoagulant treatment in VTE patients with and without IT, grouped by the use of DOACs or standard anticoagulant therapy. Among 103,818 enrolled patients, 21,089 (20.3%) were tested for IT, of whom 8422 (39.9%) tested positive: Protein C deficiency 294, Protein S deficiency 726, Antithrombin deficiency 240, Factor V Leiden 2248, Prothrombin gene mutation 1434, combined IT 3480. Overall, 14,189 RIETE patients (6.2% with IT) received DOACs, and 89,629 standard anticoagulation (8.4% with IT), mostly with heparins followed by vitamin K antagonists. Proportions of patients receiving DOACs did not differ between IT-positive and IT-negative patients. Rates of VTE recurrence on anticoagulant treatment were highest in patients with AT deficiency (P < 0.01). Rates of on-treatment major bleeding and all-cause mortality were lowest among patients with Factor V Leiden (FVL) or PT G20210A mutations, compared with patients who tested negative. Patients with IT who received DOACs had lower rates of major bleeding than those receiving standard anticoagulation. Excluding FVL and Protein S deficiency, patients with IT had lower rates of VTE recurrence with DOACs than with standard anticoagulation. DOACs are equally safe and effective in VTE patients with IT, with lower bleeding rates than those on standard anticoagulation.

Diagnosis and treatment of venous thromboembolism during pregnancy relate to genetic polymorphism.

Previous research had shown that age, a positive family history, comorbidities, major surgical operations, gestation, and use of several medications could increase the incidence of venous thromboembolism (VTE). With the development of medical and clinical individualized treatment, many people exposed to above risk factors did not develop VTE, suggested that genetic factors are also involved in the development of VTE. In this review, we aim to summarize VTE diagnosis and treatment in pregnancy women related to gene polymorphism. A comprehensive electronic search using PubMed, MEDLINE, EMBASE and Web of Science was conducted to find relevant journal articles with key search terms including: "pregnancy OR pregnant," "venous thromboembolism OR VTE," "deep vein thrombosis OR DVT," "pulmonary embolism OR PE," and "genetic OR gene." Prominent publications from establishment of database till present were analysed to achieve a deeper understanding of VTE during pregnancy relate to genetic polymorphism, and the information was then collated to form this review. The literature review revealed that inherited thrombophilia significantly associated with the development of VTE, especially the factor V Leiden (FVL) and prothrombin gene mutation (PGM). Furthermore, the role of methylenetetrahydrofolate reductase (MTHFR) gene mutation in the development of pregnancy-related VTE remains controversial, further study is required. In the present study, Marburg I polymorphism (G511E), c.1538G>A and c.1601G>A in Factor V (FV), JAK2V617F mutation were reported as an independent risk factor for VTE, there is no sufficient evidence to confirm the gene mutation is related to VTE during pregnancy, these factors appearing as another promising potential diagnostic marker of VTE during pregnancy. Besides, the dosages of heparin in the treatment of VTE during pregnancy need be adjusted according to gene polymorphism of these population, particularly FVL or PGM carriers, and this area is not studied deeply, it is worth further study. Inherited thrombophilia significantly associated with the development of VTE, especially the FVL and PGM, however the relation between MTHFR gene mutation and pregnancy-related VTE remains controversial, further study is needed. In addition, the dosages of heparin in the treatment of VTE during pregnancy suggested to adjusted based on gene polymorphism in FVL and PGM, and establish better prediction models is a direction of future research.

Factor V Leiden G1691A, Prothrombin G20210A, and MTHFR C677T Mutations among Sudanese Women with Recurrent Pregnancy Loss

Background: Various factors, such as genetic causes, anatomic abnormalities of the uterus, infectious diseases, coagulative disorders, and endocrinological and immunological diseases, might influence recurrent pregnancy loss (RLP). This study aimed to evaluate the prevalence and frequency of the FII G20210A, FVL G1691A, and MTHFR C677T polymorphisms in Sudanese women with RPL. Methods and Results: This descriptive cross-sectional study involved 100 women with a history of 3 or more RPLs (the case group) and 94 healthy multiparous women without pregnancy complications (the control group). DNA was extracted from peripheral blood samples. The study of the FII G20210A, FVL G1691A, and MTHFR C677T polymorphisms was performed by PCR and RFLP analysis. For the FII G20210A, the genotype distribution in the case group and control group was as follows: GG=97.0%, GA=3.0%, AA=0% and GG=94.0%, GA=0%, AA=0%, respectively. In the case group, the allelic distribution was as follows: G=98.5%, A=1.5%. In the control group, the A allele was absent, and the frequency of the G allele was 100%. For the MTHFR C677T, the genotypic and allelic frequencies in the case group were 97%, 3%, and 0%, respectively, for the CC, CT, and TT genotypes, and 98.5% and 1.5%, respectively, for the C and T alleles. In the control group, the genotype distribution was as follows: CC-100% CT-0%, TT-0%; the T allele was absent, and the frequency of the C allele was 100%. For the FVL G1691A, the genotype distribution in the case group and control group was as follows: GG=92.0%, GA=8.0%, AA=0% and GG=93.6%, GA=6.4%, AA=0%, respectively. For G and A alleles, the frequencies were 96.0% and 4.0%, respectively, for the case group, and 96.8% and 3.2%, respectively, for the control group. Our analysis did not reveal a significant positive association between the MTHFR C677T, FII G20210A, and FVL G1691A polymorphisms and the risk of RPL across the dominant model, multiplicative model, and a comparison of the frequencies of the heterozygous and homozygous dominant genotypes. Conclusion: The research findings suggest that the MTHFR C677T, FVL G1691A, and FII G20210A variants do not significantly contribute to the increased susceptibility to RPL in this specific population of Sudanese women. Continued scientific inquiry is crucial for developing more nuanced and personalized strategies for the diagnosis and prevention of RPL, ultimately improving women's reproductive health.

Analytical Interference with Contrast Agents in Genetic Test Result for Thrombophilia

Background: Diagnostic and therapeutic drugs can change the laboratory results of patients by interfering with the measurement method and may compromise diagnostic efficiency. Incorrect results in biochemical tests used in the clinical follow-up of a patient during treatment may lead to improper applications. Unfortunately, this situation leads the clinician to misdiagnosis. Objective: The focus of this cross-sectional study is to investigate the effects of three different radiopaque substances commonly used in the clinic on thrombophilia molecular genetic results. Methods: Peripheric blood samples from three patients whose thrombophilia panel was planned to be studied were included. Blood samples that did not contain any radiopaque material or distilled water were studied as a control group. Except for the control group four different study groups were formed by adding distilled water, Ioversol, Fluorescein Na, and Gadobutrol. This radiopaque substances were added at a ratio of 1/10 to each patient's blood sample before DNA isolation. Prothrombin G20210A, MTHFR C677T, MTHFR A1298C, Factor V Leiden G169A and PAI-1 4G/5G mutations were studied by Real Time-PCR method. Results: There was no change at the thrombophilia panel results in the study groups compared with the control groups in patients 1 and 3. In patient 2, there was no change when the result of MTHFR C677T was compared to the results of blood+DW and blood+Gadobutrol. But there were alterations in blood+Ioversol and blood+Fluorescein Na samples; the result of heterozygous MTHFR C677T was observed to change to homozygous MTHFR C677T. Conclusion: This study showed that Ioversol and Fluorescein Na could change the results of the thrombophilia genetic analysis for MTHFR C677T mutation. It should be kept in mind that the results of the thrombophilia panel analysis may change after the injection of radiopaque substances.

Oxidative Stress and Thrombophilia: Focus on Pregnancy-Related Pathophysiological Mechanisms

Abstract Thrombophilia, characterized by an increased tendency to form blood clots, presents a substantial risk during pregnancy, potentially impacting maternal and fetal outcomes. This review explores the intricate relationship between thrombophilia and oxidative stress, shedding light on their combined influence on blood clot formation. Specifically, endothelial dysfunction, driven by oxidative stress, emerges as a pivotal factor in thrombophilia, setting the stage for increased platelet activation and altered coagulation factors. Factors like Factor V Leiden mutation, Prothrombin G20210A mutation, and deficiencies in antithrombin, protein C, and protein S contribute to the pro-thrombotic state observed in thrombophilia. Furthermore, inflammation, closely intertwined with oxidative stress, exacerbates the risk of blood clot formation. Inflammatory responses lead to endothelial activation, altered endothelial function, and increased adhesion molecules expression, disrupting the delicate balance between pro- and anti-coagulant factors. Chronic inflammatory conditions, such as autoimmune disorders, potentiate a persistent state of heightened clotting risk. Additionally, impaired antioxidant defenses compound the prothrombotic state by allowing the accumulation of reactive oxygen species, thereby contributing to oxidative stress-induced endothelial dysfunction. Understanding the interplay between these factors is crucial for tailored thrombophilia management, particularly in pregnancy. Treatment strategies encompass a multifaceted approach, including anticoagulant medications, lifestyle modifications, and targeted interventions to improve endothelial health. The complex nature of thrombophilia underscores the need for a collaborative healthcare approach, involving hematologists and high-risk pregnancy specialists. Early detection, vigilant monitoring, and timely intervention are paramount in mitigating risks for both mother and baby.

Inherited Thrombophilia and Risk of Thrombosis in Children with Cancer: a Single-center Experience.

Thrombosis is an increasingly recognized complication of childhood malignancy and its treatment. The incidence and etiology of pediatric cancer-related thrombosis is still not well understood. The aim of this study was to evaluate the prevalence of common prothrombotic genetic conditions in children with cancer, the frequency of thrombosis, and the role of inherited thrombophilia in the development of thrombosis in a pediatric oncology population. Forty-seven children (36 treated for hematological malignancies and 11 for solid tumors) with a median age of 8.8. years (range 0.4 - 19.3 years) were included in the study. Genetic polymorphisms of Factor V Leiden (G1691A), prothrombin G20210A, and methylenetetrahydrofolate reductase (MTHFR) C677T were determined by real-time polymerase chain reaction-based DNA analysis. Four (8.5%) patients were heterozygous for Factor V Leiden, 3 (6.4%) were heterozygous for prothrombin G20210A mutation, and 3 (6.4%) were homozygous for MTHFR C677T mutation. All patients had implanted central venous catheters. Four (8.5%) children had documented thrombosis, three of which were in the upper venous system. Two of the four patients with thrombosis had Factor V Leiden heterozygosity. Thrombosis is an important complication of childhood cancer. The risk of thrombosis may be increased in patients with Factor V Leiden. In the absence of consensus guidelines, our results support the recommendation for thrombophilia screening in children with cancer.

Condiciones trombofilicas y su riesgo en una cohorte latinoamericana de gestantes, estudio observacional descriptivo

Objective: To evaluate thrombophilias associated with venous thromboembolism during pregnancy. Methods: Descriptive observational study. Clinical and laboratory alterations were analyzed, as well as the classification of the related profile of a cohort of Latin American pregnant women with thrombotic events during gestation and up to the 120-day puerperium. Antiphospholipid syndrome antibodies, coagulation protein C, S, antithrombin III, mutations against factor V Leiden, mutations in methylenetetrahydrofolate reductase, hyperhomocysteinemia, prothrombin mutation, and elevation of factors VIII, IX, and XI were performed. Results: The mean age was 24,5 + 7,6 years, of which 9 patients (10,3%) had a history of thromboembolism, 23 patients (26,4%) had had at least one fetal loss. Elevated antiphosphatidylserine antibodies were found in 23 patients (26,4%), elevated antibodies against beta2-glycoprotein in 20 patients (22,9%), positive lupus anticoagulant in 16 patients (18,3%), elevated factor VIII in 13 patients (14,94%), elevated factor IX in 15 patients (17,2%), elevated factor XI in 12 patients (13,7%), prothrombin mutation in 7 patients (8,07%) and the others to a lesser extent. Conclusions: The results found here point to the high prevalence rate of underdiagnosed thrombophilic disorders in pregnant women. There is still a lack of strong evidence to analyze this relationship with worse results during pregnancy. Keywords: Coagulation, Thrombosis, Gynecology.

An Interesting Case of a Patient with Prothrombin Gene (G20210) Mutation Developing a Thromboembolic Stroke

Introduction: Stroke is frequently diagnosed in the Emergency Department in older adults. Signs and symptoms are wellknown within the patient population, leading to established stroke workups in the hospital setting. When a younger adult presents with a stroke, an extensive workup is warranted for non-modifiable risk factors including hypercoagulability states, malignancy, and medication. Case Report: We present a case of a 51-year-old male with an extensive past medical history including ischemic strokes, left ventricular thrombus, and myocardial infarction, who presented with a stroke. After an extensive workup, he was diagnosed with Prothrombin gene (G20210A) mutation. Discussion: Prothrombin gene (G20210A) mutation is the second most common inherited thrombocytopenia and is highly associated with venous clots. However, extremely rare cases have occurred involving arterial clots, specifically in the brain. Conclusion: This case highlights the wide range of etiology for stroke and that extensive workup, particularly in patients under the age of 65, is critical to preventing future events.

The Contribution of Inherited Thrombophilia to Venous Thromboembolism in Cancer Patients.

Although the relationship between venous thromboembolism (VTE) and cancer has been a subject of study, knowledge of the contribution of thrombophilia to thrombosis in patients with cancer is still very limited. The aim of this article is to collect present knowledge on the contribution of inherited thrombophilia to VTE in cancer patients. We performed a search in Google Scholar and PubMed and selected 21 from 76 returned articles. Then we made a narrative review of the selected articles. We describe 11 studies on the contribution of inherited thrombophilia to VTE in cancer patients in general and 10 on that contribution in specific types of cancer: 1 in colorectal cancer, 4 in breast cancer, 1 in gynecologic cancer and 4 in hematopoietic malignancies. All studies investigate the relation of factor V Leiden (FVL) to VTE, 13 that of the prothrombin G20210A mutation (PTG20210A) and 7 studies also investigate other inherited thrombophilias, such methylenetetrahydrofolate reductase gene mutations, although only 2 investigate the contribution of deficiencies of the natural anticoagulants. Studies are very heterogeneous, in design and sample size and conclusions differ considerably. There is no consensus on the contribution of inherited thrombophilia to VTE in cancer patients except for acute lymphoblastic leukemia in children. Probably, that contribution is not the same for all types of cancer and more studies are needed to bring more knowledge on this subject.

Maternal inherited thrombophilia and recurrent pregnancy loss: a Tunisian study and review of literature.

Inherited thrombophilia, mainly the Factor V Leiden (FVL) and Prothrombin mutation (PTM) are the most risk factors for venous thrombosis especially during pregnancy and was strongly associated with recurrent pregnancy loss (RPL), a devastating reproductive problem that affects more than 1% of couples who are trying to conceive. The frequencies also the correlation among these polymorphisms and RPL have been reported controversially in various populations. In this study we evaluated the presence inherited thrombophilia amongst 35 Tunisian women with more than 2 miscarriages, referred to our genetic counseling. DNA was extracted from peripheral blood samples and PCR-RFLP was performed for the molecular diagnosis of mutation. FVL and PTM were detected in 5.7 % and 2.9% respectively; in women with a particular history of early fetal loss and thrombotic events. This study emphasizes the importance of testing for FVL and FIIM in women with RPL; mainly in the context of thrombotic events. Multi-center collaboration is necessary to clarify the real impact of thrombotic molecular defects on the pregnancy outcome, to ascertain the effect of inherited thrombophilia on recurrent pregnancy loss and then to evaluate the appropriate therapeutic approach.

Frequency of thrombophilia-associated mutations and polymorphisms in pregnant women with a history of thrombosis or pregnancy complications

Abstract Objectives To assess the frequency of multiple thrombophilia-associated mutations and polymorphisms in a selected population of high-risk pregnancies. Methods Thrombophilia screening was performed for 1,500 pregnant women with prior pregnancy complications or thrombotic events. Nine thrombophilia-associated mutations or polymorphisms were screened: factor V Leiden, factor V H1299R, prothrombin G20210A, MTHFR C677T, MTHFR A1298C, factor XIII V34L, PAI-1 4G/5G polymorphisms, EPCR G4600A, EPCR C4678G. Results Out of the 1,500 patients, 1,291 fulfilled the criteria for data interpretation. All patients had low-risk thrombophilia-associated genetic variants. Only 1.24 % of cases presented high-risk abnormalities (homozygous factor V Leiden/prothrombin G20210A, or both mutations in heterozygous form). Heterozygous factor V Leiden occurred in 10.38 % of cases, while only 5.81 % carried heterozygous prothrombin G20210A mutation. The frequency of prothrombin G20210A mutation was higher (10.37 %) in the subgroup associating factor V Leiden, than in the subgroup lacking it (5.36 %). Low-risk genetic variants occurred with a higher frequency: 23.78 % factor V H1299R, 57.32 % MTHFR C677T, 55.54 % MTHFR A1298C, 44.07 % factor XIII V34L, 73.20 % PAI-1 4G/5G polymorphisms, 69.64 % EPCR G4600A, and 69.63 % EPCR C4678G. Conclusions All patients had at least one prothrombotic genetic mutation or variant. Our data highlight the need for thrombophilia screening, including low-risk genetic variants, in a high-risk population of pregnant women with a history of pregnancy complications or thrombotic events.

The relevance of prothrombotic genetic variants in women who experienced pregnancy loss or embryo implantation failure: A retrospective analysis of 1922 cases.

The aim of our study was that to assess the allelic and genotype frequencies of nine prothrombotic gene variants in patients with a history of pregnancy loss and recurrent pregnancy loss (RPL). Women who underwent assisted reproductive technology (ART) with ongoing pregnancy and those with recurrent implantation failure (RIF) were also included. Nine prothrombotic gene variants were evaluated: factor V Leiden (FVL), factor V, H1299R variant (FVR2), factor II (FII) G20210A, methylene-tetrahydrofolate reductase (MTHFR) C677T and A1298C, beta-fibrinogen -455G>A, factor XIII (FXIII) V34L, human platelet antigen-1 (HPA-1) L33P variants, and plasminogen activator inhibitor-1 (PAI-1) 4G/5G. The following study groups were assessed: (1) women who experienced one (n = 334) or two (n = 264) episodes of pregnancy loss; (2) 468 women who experienced RPL; (3) 214 women who underwent ART followed by ongoing pregnancies; and (4) 282 women who experienced RIF after ART, that is, three or more consecutive implantation failures following high-quality embryo transfers to the uterus with an appropriate endometrium. As control group, 430 subjects from the general population were enrolled. FVL, the -455G>A variant of beta-fibrinogen, and PAI-1 4G were associated with a higher risk of developing RPL compared with the general population. Furthermore, FVL, FVR2, FII G20210A and MTHFR C677T conferred a significantly higher risk of RIF in women who performed ART compared with the general population. No statistical differences between the general population and other study groups were observed. Specific prothrombotic genetic variants are more frequently expressed in women with RPL and RIF, supporting their role in the development of polimicrothrombosis and impairing the invasion during embryo implantation.

Association between Hereditary Angioedema and Venous Thromboembolism in a Large Population-Based Case-Control Study

Introduction: Hereditary Angioedema (HAE) is a rare congenital disorder primarily caused by mutations in the SERPING1 gene that results in C1 inhibitor (C1INH) deficiency or dysfunction. C1INH is a multifunctional serine protease inhibitor that functions as a major endogenous negative regulator of the kallikrein-kinin, contact pathway of coagulation and complement systems. HAE typically presents with episodes of unpredictable subcutaneous and submucosal swelling. However, HAE patients also have evidence of systemic activation of coagulation including elevated plasma prothrombin fragments, thrombin antithrombin complexes and D-dimers. Further, patients with HAE have recently been reported to have an increased risk of venous thromboembolism (VTE). Methods: To evaluate the risk of VTE in patients with HAE we conducted a large population-based case-control study leveraging data from the United Kingdom Clinical Practice Research Datalink (CPRD). The CPRD Aurum dataset used here maintains anonymized electronic medical records of over 40 million individuals from over 1600 primary care practices in the United Kingdom. SNOMED CT medical codes were used to identify a cohort of 2,198 patients diagnosed with HAE between 1992 and 2022 in the CPRD Aurum dataset with a matched (age, gender, family practice, and index date for HAE) cohort of 4,376 controls selected. VTE events including deep vein thrombosis (DVT) and pulmonary embolism in the HAE case and control cohorts were identified using SNOMED CT medical codes. The Cox proportional hazards model was used to determine hazard ratios (HR) for VTE events in HAE cases versus controls adjusting for covariates age, sex, body mass index, blood pressure, smoking status and a number of co-morbidities specifically; neoplasm, type 2 diabetes, ischemic heart disease, chronic obstructive pulmonary disease, chronic kidney disease, autoimmune disorders and depression. Results: A greater proportion of the HAE cases were female (62%) with a mean age at HAE diagnosis of 37 years. The median follow-up period for both cases and controls was 17 years (interquartile range (IQR):8-28 years). The overall incidence of VTE in HAE cases was 1.1/1000 patient years versus 0.6/1000 patient years in the control cohort. In unadjusted analyses HAE was associated with a significantly increased risk of VTE (HR 1.70, 95% CI 1.37-2.22, P&amp;lt;0.0001). Importantly, in adjusted analyses HAE remained significantly associated with an increased risk of VTE (HR 1.44, 95% CI 1.12-1.83, P=0.004, Figure 1). Of note, this association is similar in magnitude to that previously reported for heterozygous carriers of FV Leiden, the prothrombin gene mutation and high confidence loss of function mutations in Protein C and Protein S in comparable population-based case-control studies. In adjusted sub-analyses HAE was associated with a significantly increased risk of DVT (HR: 1.42, 95% CI 1.09-1.87, P=0.01) with a trend towards an increased risk of PE (HR 1.37, 95% CI 0.84-2.27, P=0.2). Conclusions: The results of this population-based case-control study, roughly an order of magnitude larger in size than prior reports, demonstrate that HAE is associated with a significantly increased risk of VTE similar to that reported for common hereditary thrombophilias. These findings reinforce the important role of endogenous C1INH as a negative regulator of prothrombotic processes involved in VTE in the setting of HAE.

Deciphering Thrombosis Risk in Vexas Syndrome Patients through Thrombin Generation Assay Andthromboelastography

Introduction: VEXAS syndrome (for Vacuoles in myeloid progenitors, E1 ubiquitin ligase, X-linked, Autoinflammatory manifestations and Somatic) is the consequence of the clonal expansion of hematopoietic stem or progenitor cells with somatically acquired mutation of UBA1. VEXAS is a rare disease characterized by a variety of autoinflammatory manifestations and frequently associated with other hematological malignancies. Venous (VTE) and arterial thrombosis (AT) are recurrently observed in disease course and may affect up to 50% of patients. The exact pathophysiological mechanism underlying thrombosis genesis in UBA1 mut patients is not yet elucidated. Thrombin generation assay (TGA) and thromboelastography (ROTEM) are global hemostasis assays that might be used to identify hemostatic profiles at risk of thrombosis (Ay C et al. J Clin Oncol 2011). In this study, we aimed to evaluate TGA and ROTEM as potential surrogate markers of clot formation in UBA1 mut patients to predict their risk for thrombosis. Methods: TGA and ROTEM assays were performed in UBA1 mut patients between March 2022 and July 2023 , in Hospices Civils de Lyon, France. Patients were tested whether or not they had a personal history of VTE/AT. For patients already treated with oral anticoagulant interfering with exploratory assays, a temporary heparin switch was realized. TGA allows to evaluate concentration of generated thrombin through time, resulting in a dynamic thrombin generation curve, from which various parameters can be determined that describe thrombin activity, such as endogenous thrombin potential (ETP; area under the TG curve). Regarding ROTEM, analyses have been performed on citrated tubes using the ROTEM delta. For each test, the parameters CT (clotting time in seconds), A5 and A10 (measured clot amplitude at 5 and 10 minutes in mm), angle alpha (velocity in °), maximum clot firmness (in mm) and LI30 (% clot lysis at 30 minutes) have been measured. Results: We screened 15 UBA1 mut patients, while only 14 were evaluable for TGA/ROTEM (1 patient excluded due to concomitant use of apixaban the day of TGA). Five out of 15 (33%) had an history of VTE (N=3) or AT (N=2) at the time of TGA/ROTEM blood tests. With a median follow-up of 11.8 months after hmostastic explorations, none of screened patients experienced VTE/AT. On the 14 evaluable patients, TGA/ROTEM exploration was performed in 4 of them at the time of diagnosis prior any treatment onset (including steroids). Active disease (defined by increased CRP and/or clinical manifestations) at the time of TGA did not influence significantly time to peak (mins), peak thrombin (nM) and endogeneous thrombin potential (ETP, nM. min) either in platelet rich- and platelet poor- plasma. Interestingly, patients with prior history of VTE/AT (N=4) had significantly higher ETP compared to those without thrombosis history (N=10) either in platelet rich- and platelet poor-plasmas. Moreover, UBA1 mut patients without thrombosis history exhibited similar ETP values than controls ( figure 1). There was no significant correlation between type of UBA1 mutation, UBA1 allelic frequency, concomitant MDS, type of treatment at the time of TGA assay. Regarding ROTEM analysis, there was no significant differences in clot formation between patients with or without thrombosis history in EXTEM, NATEM, and FIBTEM channels. However, in TEMACT channel (activation as in EXTEM but with a plasminogen activator), we observed higher MCF (Maximum Clot Firmness) in UBA1 mutpatients with prior history of VTE/AT ( Figure 2). Acquired and inherited thrombophilia (protein C and S activities, lupus anticoagulant, anticardiolipine antibodies, anti-beta2 GP1 antibodies, factor V Leiden and prothrombin G20210A mutations, antithrombin evels) were explored in 8 out 15 of our patients. Two of them harbored lupus anticoagulant but without antiphospholipid antibodies. They do not have eitherthrombosis history or higher ETP levels. Conclusions: Based on these preliminary results, TGA and more specifically ETP might identify UBA1 mutpatients at risk of VTE or AT. ROTEM identified an hypofibrinolytic phenotype UBA1 mutpatients with thrombosis history paving the way for future explorations. The small sample size and the retrospective (post-VTE/AT) nature of these explorations are main limitations of this study, which need to be confirmed with a larger follow-up.

Meta-Analysis of National-Level Genotyping Datasets to Determine the Risk of Thrombosis in Double Heterozygous Carriers of Factor V Leiden and the Prothrombin G20210A Mutation across 876,417 Individuals

Introduction Factor V Leiden (FVL) and the prothrombin G20210A mutation (PTGM) are well-known genetic risk factors for venous thrombosis. However, the clinical significance of double heterozygosity (DH) for FVL and PTGM remains poorly understood. Prior studies of the DH genotype have produced varying risk estimates and were limited by small sample size, heterogenous case and control groups, inclusion restricted to patients presenting for medical attention, and a lack of adjustment for potential confounders. Leveraging deeply-phenotyped, population-scale genomic datasets offers a unique opportunity to surmount these shortcomings and arrive at a more robust estimate of the risk experienced by DH individuals. Methods We utilized two large-scale population-level registries with paired genetic and phenotypic data: the UK Biobank (UKBB) and the FinnGen project. Our analyses focused on 6 genotypes: FVL heterozygous (FVL het), PTGM heterozygous (PTGM het), FVL homozygous (FVL hom), PTGM homozygous (PTGM hom), double heterozygous (DH), and wild-type for both PTGM and FVL (WT). Four thrombotic phenotypes were evaluated, including stroke (CVA), myocardial infarction (MI), peripheral artery disease (PAD), and venous thromboembolism (VTE). Multivariate Firth's logistic regression models adjusting for age, sex, and principal components of ancestry were used to assess risk of thrombotic events between genotypic groups. Sensitivity analyses included 1) restricting the Firth's regression to unrelated participants, and 2) controlling for additional covariates including body mass index (BMI), blood group, smoking status, platelet count, and C-reactive protein (CRP). An additional interaction term for the FVL and PTGM mutations was examined to evaluate whether the two variants functioned in an additive or multiplicative manner. The results were combined using random-effects meta-analysis. Rates of incident VTE were compared between WT and DH individuals using Cox proportional hazards regression and Kaplan Meier analysis. Results In total, we analyzed 485,835 individuals in the UKBB and 390,582 individuals in the FinnGen project. Between the two cohorts, 806,273 individuals were WT, 13,683 were PTGM het, 69 were PTGM hom, 36,600 were FVL het, 402 were FVL hom, and 646 were double heterozygous. As expected, after adjustment for age, sex, and ancestry, an increased risk of VTE was associated with PTGM het (OR = 1.88, 95% CI: 1.56 - 2.26, p = 2.7 x 10 -11) and FVL het (OR = 2.27, 95% CI: 2.03 - 2.54, p = 1.5 x 10 -47) relative to the WT genotype. By contrast, individuals with the DH genotype demonstrated a markedly higher VTE risk relative to WT than either singly heterozygous genotype (OR = 5.24, 95% CI: 3.99 - 6.89, p = 1.4 x 10 -32) ( Figure 1). None of the mutant genotypes was associated with a significantly increased risk of CVA, MI, or PAD, except FVL het carriers experienced a marginally increased risk for PAD, as previously described (OR = 1.17, 95% CI: 1.10 - 1.24, p = 5.2 x 10 -7) ( Figure 2). Estimates for VTE risk associated with the DH genotype were not appreciably different after restricting the analysis to unrelated individuals (OR=5.66, 95% CI: 3.65-8.77, P = 9.7 x 10 -15) or adjusting for additional risk factors (OR=4.40, 95% CI: 3.33-5.72, P = &amp;lt; 1.0 x 10 -16). While VTE risk in individuals with DH genotype appeared additive, we observed a statistically significant interaction term for the two constituent genotypes (OR = 1.3, 95% CI: 1.05 - 1.60, p = 0.017). This finding suggests that although there is a statistically significant multiplicative interaction between the two mutations, they likely behave in an additive manner for the purposes of clinical care. Finally, we found that the rate of incident VTE was significantly higher among PTGM het individuals (P=8.5 x 10 -15), FVL het individuals (P &amp;lt;2 x 10 -16), and DH individuals (P=7.6 x 10 -5) compared to those with the WT genotype. Conclusion and Relevance We have conducted the largest study to date of double heterozygosity for FVL and PTGM. After adjustment for common confounders, DH individuals demonstrate an increased risk of VTE relative to singly heterozygous individuals. By contrast, we found no evidence that DH individuals are at significantly increased risk for arterial thrombosis. Our work may help resolve longstanding uncertainty around the clinical impact of the DH genotype on thrombotic risk.

Real World, Single-Centre Experience of Pregnancy in Patients with Philadelphia Negative Myeloproliferative Neoplasms

Pregnancy in myeloproliferative neoplasms (MPN) is commonly associated with maternal and foetal complications due to increased risks of thromboembolic and haemorrhagic events and placental dysfunction. The incidence of UK pregnancies in MPN is estimated as 3·2/100 000 maternities per year (Alimam, S., et al 2016, Br J Haematol 2016; 175:31-36; Robinson et al, Br J Haematol 2020;189:625-34). Here we present pregnancy outcomes of MPN patients attending University College London Hospital (UCLH), a large UK tertiary referral centre, between 2015 and 2023. Twenty-three patients were identified with a median age at MPN diagnosis of 33 years (range (r), 13 - 46). The majority of patients (21/23, 91.3%) had a diagnosis of ET or triple negative (TN) thrombocytosis and 8.7% (2/23) a diagnosis of polycythaemia vera (PV). In 61.4% of pregnancies, diagnosis was known at conception. Regarding mutational status, JAK2V617F was present in 10/23 (43.5%) patients, CALR in 5/23 (21.7%) and MPL in 1/23 (4.3%). The remaining 7/23 (30.4%) patients were TN. Median VAF for JAK2V617F and CALR were 15.8% (r, 21.1 - 33%) and 25.9% (r, 5.7 - 46%), respectively. The cohort collectively experienced 57 pregnancies, 38 of which were managed at UCLH. Focusing on pregnancies managed at UCLH, median age at pregnancy was 34.5 years (r, 22 - 47). Conception was spontaneous in 31/38 (81.6%) pregnancies. Six (15.8%) patients required assisted conception and had a higher median age of 38.5 years (r, 35 - 47). Where gestation at delivery was known, 92.6% (25/31) of live births delivered at term (&amp;gt;37 weeks). Caesarean rate was significant at 41.9% (13/31), of which 61.5% were emergency sections. The live birth rate of the 57 overall pregnancies was 76.9% and 88.6% in the 38 managed at UCLH. At UCLH, we adopt an individualised approach to managing pregnant women with MPNs, working alongside obstetricians and obstetric haematology colleagues. Consequently, as shown in Table 1, there were bespoke regimens for individual patients. Low dose aspirin was prescribed throughout pregnancy in the majority (78.9%, 30/38) of pregnancies. In 18.4% (7/38), cytoreduction was established prior to pregnancy. In 42.9% (3/7), pegylated interferon (PegIFN) was commenced to optimise counts prior to pregnancy and in 42.9% (3/7) as long term count control. One patient was cytoreduced with hydroxycarbamide prior to pregnancy and subsequently switched to PegIFN. Low molecular weight heparin (LMWH) was administered at some point during pregnancy in 60.9% (14/23) of patients and 57.9% (22/38) of pregnancies. 65.8% (25/38) underwent monitoring with uterine artery (UA) dopplers. Median gestation for UA assessment was 20 weeks (r, 19 - 28). UA dopplers were reported as abnormal in 16% (4/25). In two patients, this was due to a raised combined pulsatility index, UA notching in one and was unspecified in one patient. Nine (39.1%) patients experienced foetal loss, with 12 miscarriages recorded across the total 57 pregnancies and 4 miscarriages in the 38 pregnancies managed at UCLH. Median maternal age was 31.5 (r, 24 - 42) and median gestation was 8 weeks (r, 5 - 24). Six (66.7%) patients experiencing foetal loss had a diagnosis of ET, 2 (22.2%) PV and 1 (11.1%) TN thrombocytosis. Three miscarriages occurred in one patient, who demonstrated a concurrent heterozygous prothrombin G20210A mutation in addition to ET. Eight (34.8%, 8/23) patients collectively experienced 11 haemorrhagic events. The majority (72.7%) were post-partum haemorrhage (PPH), 37.5% of which were classified as major or severe. Three (27.3%) bleeding events occurred whilst on aspirin monotherapy, 3 (27.3%) on combined LMWH and aspirin, 1 (9.1%) on LWMH alone and 1 (9.1%) on LMWH and PIFN. With regards to thrombosis, one patient with undiagnosed ET had a cerebral venous sinus thrombosis at 11-weeks gestation. A total of 2/23 (8.7%) patients' pregnancies resulted in hypertensive complications and pre-eclampsia, both resulting in delivery with caesarean section at 34 and 35 weeks. Although the live birth rate is encouraging, our data highlights that patients with MPN remain at increased risk of miscarriage, early delivery and haemorrhagic events. There remain inconsistencies in the management of pregnancy in MPN and, although we adopt an individualised patient-centred approach, there is an unmet need for further study and development of evidence based treatment algorithms.

Investigation of Plasminogen Activator Inhibitor-1 (PAI-1) 4G/5G promoter polymorphism and other thrombophilia genes in patients with acute pulmonary embolism

Abstract Background Venous thromboembolism (VTE) is a serious threat to life and health, commonly known as the silent killer. Recent study has found that VTE is a polygenetic disease and more than 60% of deep vein thrombosis risk is influenced by genetic factors [1]. PAI-1 is a serine protease with negative feedback to fibrinolysis, activating and inhibiting coagulation [2]. The aim of this study was to elucidate the clinical impact of the PAI-1 4G/5G polymorphism and other thrombophilia in patients with acute PE. Methods A total of 58 subjects with acute PE and 60 healthy controls, were recruited in Institute of Cardiology. The accuracy of the RT-PCR method for detecting F5 G1691A (FVL) and PAI-1 4G/5G polymorphisms was evaluated by using sequencing method as the gold standard. Moreover, the association of the PAI-1 4G/5G polymorphism with susceptibility, treatment efficacy and recurrence status were explored. Eventually, we evaluated the association with inherited thrombophilia genes, such as the coagulation Factor V Leiden, prothrombin G20210A, FGB-455 G/A and methylenetetrahydrofolate reductase C677T and 1298 A/C. Results It was noted that the vast majority of patients with acute PE (87.9%) present polymorphism in the PAI-1 gene (29.3% homozygous (4G/4G) and 58.6% heterozygous (5G/4G)). Eleven patients out of 58 (19% of patients) showed factor V Leiden mutation and 19 patients out of 58 (32,7% of patients) showed mutation in FGB-455 G/A (2 homozygotes); MTHFR C677T gene mutation was found in 55,2%, while prothrombin 20210A gene mutation was presented in 6 patients (10.3% of patients). Nine patients (15,5% of patients) presented with chronic complication of VTE and 38.7% of patients showed recurrent pulmonary embolism. More than a half of patients (51.9%) had multiple gene mutation and only one presented with mutations in three studied genes. It showed a significant difference in the occurrence of other thromboses in the body and significant increase in the recurrence of pulmonary embolism and residual complications in these patients. It was also observed that individuals with the 4G/5G genotype had lower neutrophil counts and neutrophil-to-lymphocyte ratio (NLR) than the 5G/5G genotype. Furthermore, it was underlined that the patients with the 5G/5G genotype were more likely to achieve complete recanalization compared to the 4G/4G genotype. Individuals carrying the 5G/5G genotype were more likely to develop a recurrence-free status as compared to those with the 4G/4G or 4G/5G genotypes. PAI-1 antigen levels in the VTE group were significantly higher than those in the HC group. Conclusion The PAI-1 4G/5G polymorphism has potential value in assessing the prognosis of patients with VTE. This study has laid the foundation for the application of PAI-1 4G/5G polymorphism in the personalized management and monitoring of patients with VTE. According to this study results PAI-1 4G/5G polymorphism could be included in laboratory testing panel of thrombophilia.

Abstract 16199: Postsurgical Takotsubos Complicated by Clot Burden in the Setting of Heterozygous Prothrombin Gene Mutation

Introduction: Postsurgical Takotsubo cardiomyopathy (TCM) is associated with acute stress secondary to catecholamine release causing reversible left ventricular (LV) failure. We present a diagnostically challenging presentation of postsurgical TCM with underlying prothrombin gene mutation. Case Presentation: A 53 year old female underwent laparoscopic hysterectomy 2 days prior to presentation with chest pain and shortness of breath. Vitals were unremarkable, labs showed elevated troponin and EKG consistent with NSTEMI. CTA chest demonstrated significant clot burden to the ascending and descending aorta. Echocardiogram revealed a reduced ejection fraction (EF) of 25-30% with apical ballooning and thrombus. She was admitted on heparin drip and completed an infusion of eptifibatide for 24 hours. Repeat CTA chest demonstrated mildly reduced clot burden. Left heart catheterization (LHC) was precluded due to aortic arch clot. Coronary CTA revealed no CAD with a calcium score of 0. Coagulopathy workup showed heterozygous prothrombin G20210A variant. She was discharged on warfarin. Repeat echocardiography 1 month later showed improved EF to 40-45%. Discussion: TCM accounts for 1-3% of cases of acute coronary syndromes (ACS) and affects women at a rate of 90%. Studies have shown that TCM with apical ballooning is minimally associated with LV thrombus . The presence of heterozygous prothrombin gene mutation increases risk of clot formation by 2 to 3 times. Surgery can cause this risk to dramatically increase. Coronary CTA was the best noninvasive approach to make the diagnosis as the risk of LHC was too great given the anatomic challenge of the aortic arch clot. We advocate for hypercoagulable workups to inform management of anticoagulation in patients with clotting events without known risk factors for thrombus formation.