Thrombophilia is a hypercoagulable state that may have a genetic basis (inherited) or can be acquired. It is a multifactorial condition and only the mutual interactions between the environment and genes may lead to the development of clinical manifestation. This state is the main factor promoting venous (rarely arterial) thromboembolism (VTE). Inherited thrombophilia is mainly associated with two pathogenic variants in the V coagulation factor (FV) and the prothrombin (FII) genes. The aim of our study was to evaluate the frequency of two pathogenic variants in FII and FV genes as inherited thrombophilia factors in a group within the Polish population in comparison with other described populations.

Aiming to evaluate the role of ten functional polymorphisms in long COVID, involved in major inflammatory, immune response and thrombophilia pathways, a cross-sectional sample composed of 199 long COVID (LC) patients and a cohort composed of 79 COVID-19 patients whose follow-up by over six months did not reveal any evidence of long COVID (NLC) were investigated to detect genetic susceptibility to long COVID. Ten functional polymorphisms located in thrombophilia-related and immune response genes were genotyped by real time PCR. In terms of clinical outcomes, LC patients presented higher prevalence of heart disease as preexistent comorbidity. In general, the proportions of symptoms in acute phase of the disease were higher among LC patients. The genotype AA of the interferon gamma (IFNG) gene was observed in higher frequency among LC patients (60%; p = 0.033). Moreover, the genotype CC of the methylenetetrahydrofolate reductase (MTHFR) gene was also more frequent among LC patients (49%; p = 0.045). Additionally, the frequencies of LC symptoms were higher among carriers of IFNG genotypes AA than among non-AA genotypes (Z = 5.08; p < 0.0001). Two polymorphisms were associated with LC in both inflammatory and thrombophilia pathways, thus reinforcing their role in LC. The higher frequencies of acute phase symptoms among LC and higher frequency of underlying comorbidities might suggest that acute disease severity and the triggering of preexisting condition may play a role in LC development.

Reports on the incidence of intracardiac thrombi (ICT) have increased over the last few decades, but ICT are still relatively rare among children. Left ventricular systolic dysfunction and dilatation may contribute to the formation of ICT, especially when a hypercoagulable state exists. The aim of this study was to describe the incidence of ICT in children suffering from cardiac failure with left ventricular dysfunction and to identify risk factors on admission for developing ICT.

To estimate the relationship between the risk of preeclampsia and two thrombophilia gene single-nucleotide polymorphisms (SNPs), the factor V G1691A SNP and the prothrombin G20210A SNP.

Thrombophilia is a multifactorial disorder that arises from the interaction of acquired and genetic risk factors. Despite the significant efforts made to understand the etiology of this disease, there are still a certain number of patients suffering from idiopathic thrombophilia. The aim of this study was to screen the 3' end of the prothrombin (FII) gene, which is susceptible to gain-of-function mutations due to its non canonical architecture, in patients with idiopathic thrombophilia and to determine its eventual role in the pathogenesis of thrombophilia. This study was carried out in 100 patients with idiopathic thrombophilia and 100 healthy controls. DNA variants in the 715 bp long region of the 3' end of the prothrombin gene were identified by sequencing. In our study, we detected two variants: A19911G and C20068T. The frequency of the A19911G gene variant was slightly increased in the group of patients compared to controls, however with no statistically significant difference compared to controls [odds ratio (OR) = 1.06; 95% confidence interval (95% CI) 0.53-2.13]. Heterozygous carriers of the FII C20068T gene variant were four times more frequent in patients (4.0%) than in controls (1.0%), but this difference did not reach statistical significance (OR = 4.12; 95% CI 0.45-37.57). Our findings suggest that variant A19911G is not a significant risk factor, while C20068T may represent a potential risk factor for idiopathic thrombophilia. To confirm our results, further studies should be conducted in a larger cohort of patients.

Introduction  Testing for inherited and acquired thrombophilias adds to the cost of care of patients with venous thromboembolism (VTE), though results may not influence patient management. Methods  This is a single-center, retrospective study conducted at Emory University Hospitals from January to December 2015 to (1) determine the pattern of thrombophilia testing in patients with VTE, (2) study the impact of results of thrombophilia testing on clinical decision-making, and (3) determine the direct costs of thrombophilia testing in patients with VTE. Results  Of the 266 eligible patients, 189 (71%) underwent testing; 51 (26.9%) tested positive and the results impacted management in 32 (16.9%) of tested patients. Patient undergoing testing were more likely to be younger than 40 years (30.9 vs. 18.2%), have had prior pregnancy loss (9.0 vs. 0%), or known family history of hypercoagulability (24.9 vs. 10.4%), and were less likely to have had provoked VTE (37 vs. 79.2%). The most common thrombophilias tested were antiphospholipid syndrome (60.1%), factor V Leiden (59.7%), and prothrombin gene mutation (57.5%). Direct costs of thrombophilia testing were $2,364.32 per patient, $12,331.55 to diagnose 1 positive, and $19,653.41 per patient-management affected. Conclusion  We noted significant variability in selection of patients and panel of tests, sparse utilization of test results in patient management, but high cost associated with thrombophilia testing in patients with VTE. With guidelines advocating selective use of thrombophilia testing and attention to potential impact of test results in patient management, we propose the need for measures at institutional levels to improve test-ordering practices.

Familial and acquired thrombophilia are often etiologic for idiopathic hip and jaw osteonecrosis (ON), and testosterone therapy (TT) can interact with thrombophilia, worsening ON.

Antithrombin resistance is a rare subtype of hereditary thrombophilia caused by prothrombin gene variants, leading to thrombotic disorders. Recently, the Prothrombin Belgrade variant has been reported as a specific variant that leads to antithrombin resistance in two Serbian families with thrombosis. However, due to clinical data scarcity and the inapplicability of traditional genome-wide association studies (GWAS), a broader perspective on molecular and phenotypic mechanisms associated with the Prothrombin Belgrade variant is yet to be uncovered. Here, we propose an integrative framework to address the lack of genomic samples and support the genomic signal from the full genome sequences of five heterozygous subjects by integrating it with subjects' phenotypes and the genes' molecular interactions. Our goal is to identify candidate thrombophilia-related genes for which our subjects possess germline variants by focusing on the resulting gene clusters of our integrative framework. We applied a Non-negative Matrix Tri-Factorization-based method to simultaneously integrate different data sources, taking into account the observed phenotypes. In other words, our data-integration framework reveals gene clusters involved with this rare disease by fusing different datasets. Our results are in concordance with the current literature about antithrombin resistance. We also found candidate disease-related genes that need to be further investigated. CD320, RTEL1, UCP2, APOA5 and PROZ participate in healthy-specific or disease-specific subnetworks involving thrombophilia-annotated genes and are related to general thrombophilia mechanisms according to the literature. Moreover, the ADRA2A and TBXA2R subnetworks analysis suggested that their variants may have a protective effect due to their connection with decreased platelet activation. The results show that our method can give insights into antithrombin resistance even if a small amount of genetic data is available. Our framework is also customizable, meaning that it applies to any other rare disease.

Thrombophilia is a multifactorial disorder involving environmental and genetic factors. Well‑known factors that result in predisposition to congenital disorders associated with thrombophilia include antithrombin deficiency, protein C and S deficiency, Factor V Leiden mutation, abnormal prothrombin and antiphospholipid syndrome. The present study revealed an association between a mutation of the F2 gene, which codes for coagulation factor II, thrombin, and the risk of thrombophilia in a Han Chinese family, of which four members (I‑2, II‑2, II‑3 and III‑1) had a history of deep venous thromboembolism. The disease was measured in this family using laboratory measurements and computed tomography angiography. To identify the abnormality underlying the increased thrombophilia risk, whole‑exome sequencing technology was used to analyze two affected individuals (II‑2 and III‑1). An exonic missense F2 mutation, T165M (NM_000506:c.C494T:p.T165M;rs5896), was identified from a total of 2,222 and 2,203 genetic variations observed in the two affected individuals, respectively, which were subsequently filtered and confirmed using Sanger sequencing. I‑2, II‑3 and III‑1 shared this mutation with the proband (II‑2), and II‑6 had a heterozygous form of the mutation. This deleterious mutation was not identified in normal controls. The present study may improve understanding of the function of the F2 gene.

Various inherited traits contribute to the overall risk of venous thromboembolism (VTE). In addition, the epidemiology of thrombophilia in the East-Asian VTE population remains unclear; thus, we aimed to assess the proportion of hereditary thrombophilia via a meta-analysis.

The placenta is an essential organ in the proper development of pregnancy, and it can present a lot of structural and vascular lesions that can affect fetal development. One of the pathologies associated with pregnancy, which can change the placental structure is thrombophilia (TPh), and this can be correlated with an intrauterine growth restriction (IUGR) of the fetus. Maternal clinical aspects (age, weight) can be correlated with fetal ones (weight, gender), but also with the structural and vascular aspect of the placenta. The placental structure associated with TPh and IUGR shows macroscopic changes, such as fibrin deposition, calcifications and placental infarctions, but microscopic lesions are best highlighted by classical staining techniques: Hematoxylin-Eosin (HE), Masson's trichrome (MT) and Periodic Acid-Schiff (PAS)-Hematoxylin, but also by immunohistochemistry technique with the help of anti-cluster of differentiation 34 (CD34) antibody that could make it possible to quantify vascular density depending on the pathology. Microscopic changes were massive infarcts caused by vascular ischemia, intravenous and extravillous fibrin deposits, calcifications, and vascular thrombosis. All these clinical, morphological and morphopathological data are interconnected and may vary in the presence of TPh and IUGR.

In the phase 2b/3 DIVERSITY trial, 3 months treatment with dabigatran was noninferior to standard of care (SOC) for acute venous thromboembolism (VTE) in children. In a single-arm, phase 3, secondary VTE prevention study, up to 12 months dabigatran use was associated with favorable safety. Dabigatran is approved by the European Medicines Agency and US Food and Drug Administration for pediatric indications. We assessed primary composite efficacy (complete thrombus resolution and freedom from VTE recurrence/VTE-related death) in subgroups with thrombophilia vs those with negative/unknown thrombophilia status in the DIVERSITY trial and safety in both studies. Thrombophilia types were similar between the DIVERSITY trial (total population) and secondary prevention studies: factor V Leiden, 42% vs 33%; prothrombin mutation (G20210A), 19% vs 17%; antithrombin deficiency, 15% vs 20%; protein C/S deficiency, 23% vs 25%; and antiphospholipid antibodies, 18% vs 20% of patients, respectively. In DIVERSITY, 36% and 22% of thrombophilia subgroup patients treated with dabigatran and SOC, respectively, met the primary end point (Mantel-Haenszel-weighted rate difference, -0.135; 95% confidence interval, -0.36 to 0.08; noninferiority P = .0014); comparable to the total DIVERSITY trial population (46% vs 42%) showing dabigatran noninferiority to SOC. Within this subgroup, numerically fewer patients experienced VTE recurrence or progression of index thrombus in the dabigatran treatment group vs SOC. In the secondary prevention study, VTE recurrence at 12 months occurred in 2.8% of patients with thrombophilia vs 0% with negative/unknown thrombophilia. Safety profiles were consistent with those reported previously. Although they should be interpreted with caution, these exploratory findings suggest dabigatran could be an appropriate long-term anticoagulant for children with thrombophilia. These trials were registered at www.clinicaltrials.gov as #NCT01895777 and #NCT02197416.

Thrombophilia workup is typically inappropriate in the inpatient setting as testing may be skewed by anticoagulation, acute thrombosis, or acute illness.

Clotting abnormalities are discussed both in the context with thyroid dysfunctions and obesity caused by a high fat diet. This study aimed to investigate the impact of hypo-, or hyperthyroidism on the endogenous thrombin potential (ETP), a master indicator of clotting activation, on Sprague Dawley rats fed a normal or high fat diet. Female Sprague Dawley rats (n = 66) were grouped into normal diet (ND; n = 30) and high-fat diet (HFD; n = 36) groups and subdivided into controls, hypothyroid and hyperthyroid groups, induced through propylthiouracil or triiodothyronine (T3) treatment, respectively. After 12 weeks of treatment ETP, body weight and food intake were analyzed. Successfully induced thyroid dysfunction was shown by T3 levels, both under normal and high fat diet. Thyroid dysfunction was accompanied by changes in calorie intake and body weight. In detail, compared to euthyroid controls, hypothyroid rats showed significantly increased-and hyperthyroid animals significantly decreased-ETP levels. High fat diet potentiated these effects in both directions. In summary, we are the first to show that hypothyroidism and high fat diet potentiate the thrombotic capacity of the clotting system in Sprague Dawley rats. This effect may be relevant for cardiovascular disease where thyroid function is poorly understood as a pathological contributor in the context of clotting activity and obesogenic nutrition.

Hereditary and acquired thrombophilia are risk factors for venous thromboembolism (VTE). Whether testing helps guide management decisions is controversial. These evidence-based guidelines from the American Society of Hematology (ASH) intend to support decision making about thrombophilia testing. ASH formed a multidisciplinary guideline panel covering clinical and methodological expertise and minimizing bias from conflicts of interest. The McMaster University GRADE Centre provided logistical support, performed systematic reviews, and created evidence profiles and evidence-to-decision tables. The Grading of Recommendations Assessment, Development, and Evaluation approach (GRADE) was used. Recommendations were subject to public comment. The panel agreed on 23 recommendations regarding thrombophilia testing and associated management. Nearly all recommendations are based on very low certainty in the evidence due to modeling assumptions. The panel issued a strong recommendation against testing the general population before starting combined oral contraceptives (COCs) and conditional recommendations for thrombophilia testing in the following scenarios: (a) patients with VTE associated with nonsurgical major transient or hormonal risk factors; (b) patients with cerebral or splanchnic venous thrombosis, in settings where anticoagulation would otherwise be discontinued; (c) individuals with a family history of antithrombin, protein C, or protein S deficiency when considering thromboprophylaxis for minor provoking risk factors and for guidance to avoid COCs/hormone replacement therapy; (d) pregnant women with a family history of high-risk thrombophilia types; and (e) patients with cancer at low or intermediate risk of thrombosis and with a family history of VTE. For all other questions, the panel provided conditional recommendations against testing for thrombophilia.

Aspirin is the most widely used antiplatelet agent because it is safe, efficient, and inexpensive. However, a significant subset of patients does not exhibit a full inhibition of platelet aggregation, termed 'aspirin resistance' (AR). Several major studies have observed that AR patients have a 4-fold increased risk of myocardial infarction (MI), stroke, and other thrombotic events. Arachidonic acid-stimulated whole blood aggregation was tested in 132 adults at risk for ischemic events, and identified an inadequate response to aspirin therapy in 9 patients (6.8%). Expression profiling of blood RNA by microarray was used to generate new hypotheses about the etiology of AR. Among the differentially expressed genes, there were decreases in several known platelet transcripts, including clusterin (CLU), glycoproteins IIb/IIIa (ITGA2B/3), lipocalin (LCN2), lactoferrin (LTF), and the thrombopoetin receptor (MPL), but with increased mRNA for the T-cell Th1 chemokine CXCL10. There was a strong association of AR with expression of HLA-DRB4 and HLA-DQA1. Similar HLA changes have been linked to autoimmune disorders, particularly antiphospholipid syndrome (APS), in which autoantibodies to phospholipid/protein complexes can trigger platelet activation. Consistent with APS, AR patients exhibited a 30% reduction in platelet counts. Follow-up testing for autoimmune antibodies observed only borderline titers in AR patients. Overall, these results suggest that AR may be related to changes in platelet gene expression creating a hyperreactive platelet, despite antiplatelet therapy. Future studies will focus on determining the protein levels of these differential transcripts in platelets, and the possible involvement of HLA restriction as a contributing factor.

Background Recent literature reports a strong thrombotic tendency in patients hospitalized for a coronavirus disease 2019 (COVID-19) infection. This characteristic is unusual and seems specific to COVID-19 infections, especially in their severe form. Viral infections can trigger acquired thrombophilia, which can then lead to thrombotic complications. We investigate for the presence of acquired thrombophilia, which could participate in this phenomenon, and report its prevalence. We also wonder if these thrombophilias participate in the bad prognosis of severe COVID-19 infections. Methods and Results In 89 consecutive patients hospitalized for COVID-19 infection, we found a 20% prevalence of PS (protein S) deficiency and a high (ie, 72%) prevalence of antiphospholipid antibodies: mainly lupus anticoagulant. The presence of PS deficiency or antiphospholipid antibodies was not linked with a prolonged activated partial thromboplastin time nor with D-dimer, fibrinogen, or CRP (C-reactive protein) concentrations. These coagulation abnormalities are also not linked with thrombotic clinical events occurring during hospitalization nor with mortality. Conclusions We assess a high prevalence of positive tests detecting thrombophilia in COVID-19 infections. However, in our series, these acquired thrombophilias are not correlated with the severity of the disease nor with the occurrence of thrombotic events. Albeit the strong thrombotic tendency in COVID-19 infections, the presence of frequent acquired thrombophilia may be part of the inflammation storm of COVID-19 and should not systematically modify our strategy on prophylactic anticoagulant treatment, which is already revised upwards in this pathological condition. Registration URL: https://www.clini​caltr​ials.gov; Unique identifier: NCT04335162.

Portal vein thrombosis (PVT) is common in cirrhosis. PVT is associated with high morbidity and mortality. Individual reports suggest that PVT occurs more frequently in patients with cirrhosis and inherited thrombophilia. The relationship between cirrhosis, PVT development, and inherited thrombophilia was explored in this study. The aim of the study was to determine whether cirrhotic patients with nontumoral PVT have an increased rate of inherited thrombophilia.

Acute unprovoked idiopathic fatal pulmonary embolism (IFPE) causes sudden death without an identifiable thrombogenic risk. We aimed to investigate the underlying genomic risks of IFPE through whole exome sequencing (WES).

Background Inherited thrombophilias are well-established predisposing factors for venous thromboembolism, but their role in arterial thrombosis, such as arterial ischemic stroke, remains uncertain. We aimed to evaluate the association between inherited thrombophilia (factor V Leiden, prothrombin G20210A mutation, protein C deficiency, protein S deficiency, and antithrombin deficiency) and risk of arterial ischemic stroke in adults. Methods and Results We searched PubMed, EMBASE, and Cochrane Library Databases from inception to December 31, 2018. We included case-control or cohort studies of adults reporting the prevalence of inherited thrombophilias in those with arterial ischemic stroke and subjects without arterial ischemic stroke. Two reviewers (T.C., E.D.) independently searched the literature and extracted data. Pooled odds ratios (ORs) and 95% CIs were calculated using random-effects model. We identified 68 eligible studies, which collectively enrolled 11 916 stroke patients and 96 057 controls. The number of studies reporting factor V Leiden, prothrombin G20210A mutation, protein C deficiency, protein S deficiency, and antithrombin deficiency were 56, 45, 15, 17, and 12, respectively. Compared with controls, patients with arterial ischemic stroke were significantly more likely to have the following inherited thrombophilias: factor V Leiden (OR, 1.25; 95% CI, 1.08-1.44; I2=0%), prothrombin G20210A mutation (OR, 1.48; 95% CI, 1.22-1.80; I2=0%), protein C deficiency (OR, 2.13; 95% CI, 1.16-3.90; I2=0%), and protein S deficiency (OR, 2.26; 95% CI, 1.34-3.80; I2=8.8%). Statistical significance was not reached for antithrombin deficiency (OR, 1.25; 95% CI, 0.58-2.67; I2=8.8%). Conclusions Inherited thrombophilias (factor V Leiden, prothrombin G20210A mutation, protein C deficiency, and protein S deficiency) are associated with an increased risk of arterial ischemic stroke in adults. The implications of these findings with respect to clinical management of patients with ischemic stroke require further investigation.