Prothrombin: Another Clotting Factor After FV That Is Involved Both in Bleeding and Thrombosis

The association of the prothrombin A19911G single-nucleotide polymorphism and the risk of venous thromboembolism: A systematic review and meta-analysis

BACKGROUND

The study employed meta-analysis to provide a comprehensive synthesis of evidence regarding the association between the prothrombin A19911G polymorphism and the risk of venous thromboembolism (VTE).

METHOD

The databases were searched to identify studies investigating the association between the prothrombin A19911G polymorphism and the risk of VTE. Meta-analysis was conducted using Stata 14.0 software.

RESULTS

A total of five literature studies were included, involving 14,001 participants. Meta-analysis demonstrated that prothrombin A19911G polymorphism increased the risk of VTE (G vs A: OR = 1.17, 95% CI = 1.11-1.22, p < .00001; GG + AG vs AA: OR = 1.22, 95% CI = 1.13-1.31, p < .00001; GG vs AG + AA: OR = 1.23, 95% CI = 1.14-1.33, p < .00001; AG vs AA: OR = 1.15, 95% CI = 1.06-1.25, p = .0006; GG vs AA: OR = 1.34, 95% CI = 1.22-1.48, p < .00001).

CONCLUSION

The polymorphism of prothrombin A19911G enhances the susceptibility to VTE.

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

OBJECTIVES

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.

DESIGN

Prospective cross-sectional study.

METHOD

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.

RESULTS

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).

CONCLUSION

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.

Application of anti-Xa assay in monitoring unfractionated heparin therapy in contemporary antithrombotic management

INTRODUCTION

Unfractionated heparin remains the most widely used agent in the prevention and acute treatment of thrombosis. Pharmacological complexities of this intriguing agent mandate frequent monitoring of its anticoagulant properties to maintain safe and effective hematological outcomes. Although activated partial thromboplastin time has been the standard test to monitor unfractionated heparin therapy for many decades, the anti-Xa assay has emerged as a substitute or adjunct in many institutions.

AREAS COVERED

This brief report outlines the key features of anti-Xa assay in monitoring unfractionated heparin in acute management of thrombosis in various contemporary settings, with emphasis on evidence for clinical outcomes. PubMed.gov database was utilized to obtain the pertinent literature.

EXPERT OPINION

The anti-Xa activity is primarily a reflection of UFH concentration and does not account for other hematological variables frequently present in contemporary anticoagulation management. The advantage of the anti-Xa assay in monitoring UFH therapy is predicated upon its limitations to account for global physiological hemostasis. There are significant disease and drug interactions that may potentially result in false in-vitro analysis of anti-Xa activity. Routine application of the anti-Xa assay is not evidence-based at this time.

Possible effect of genetic background in thrombophilia genes on clinical severity of patients with coronavirus disease-2019: A prospective cohort study

Background and objective: Thrombotic and microangiopathic effects have been reported in Coronavirus Disease-2019 (COVID-19) patients. In the present study, we aimed to examine the relationship between hereditary thrombophilia factors and the clinical picture severity of COVID-19 patients. Methods: Ninety COVID-19 patients were included and grouped according to the severity to three groups: severe/critical (n=30), mild/moderate (n=30) and asymptomatic (n=30). Hereditary thrombophilia genetic markers [prothrombin (FII) G20210A, factor V Leiden (FVL) G1691A, factor XIII (FXIII) V34L, methylene tetrahydrofolate reductase (MTHFR) A1298C and C677T, and plasminogen activator inhibitor-1 (PAI-1) 4G & 5G] were genotyped for all patients. Results: Seventeen (18.9%) patients had the polymorphism 4G/4G PAI-1 and 48 (53.3%) had 4G/5G. In addition, the heterozygous GA FVL, MTHRF677CT, and MTHRF1298AC polymorphisms were detected in 11 (12.2%), 26 (28.9%), and 38 (42.2%) patients, respectively. The rate of severe/critical patients with PAI 4G/5G gene polymorphism was higher than the asymptomatic+moderate/mild patients, and the rate of severe/critically ill patients with PAI 4G/4G polymorphism was found to be lower than the asymptomatic+moderate/mild patients. No difference was evidenced between the distribution of deceased and survivors of the genotype groups. Conclusions: In the present study, we found that heterozygous 4G/5G PAI-1 polymorphism is associated with critical or severe COVID-19 picture, and that FVL, MTHFR, FXIII, and prothrombin polymorphisms were not directly related to COVID-19 severity.

The Genetic Basis of Strokes in Pediatric Populations and Insight into New Therapeutic Options

Strokes within pediatric populations are considered to be the 10th leading cause of death in the United States of America, with over half of such events occurring in children younger than one year of life. The multifactorial etiopathology that has an influence on stroke development and occurrence signify the importance of the timely recognition of both modifiable and non-modifiable factors for adequate diagnostic and treatment approaches. The early recognition of a stroke and stroke risk in children has the potential to advance the application of neuroprotective, thrombolytic, and antithrombotic interventions and rehabilitation strategies to the earliest possible timepoints after the onset of a stroke, improving the outcomes and quality of life for affected children and their families. The recent development of molecular genetic methods has greatly facilitated the analysis and diagnosis of single-gene disorders. In this review, the most significant single gene disorders associated with pediatric stroke are presented, along with specific therapeutic options whenever they exist. Besides monogenic disorders that may present with stroke as a first symptom, genetic polymorphisms may contribute to the risk of pediatric and perinatal stroke. The most frequently studied genetic risk factors are several common polymorphisms in genes associated with thrombophilia; these genes code for proteins that are part of the coagulation cascade, fibrolysis, homocystein metabolism, lipid metabolism, or platelets. Single polymorphism frequencies may not be sufficient to completely explain the stroke causality and an analysis of several genotype combinations is a more promising approach. The recent steps forward in our understanding of the disorders underlying strokes has given us a next generation of therapeutics and therapeutic targets by which to improve stroke survival, protect or rebuild neuronal connections in the brain, and enhance neural function. Advances in DNA sequencing and the development of new tools to correct human gene mutations have brought genetic analysis and gene therapy into the focus of investigations for new therapeutic options for stroke patients.

Should we screen Eastern Mediterranean COVID-19 patients for inherited thrombophilia?

The inflammatory component of Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) creates a pro-thrombotic state that necessitates a thrombophylactic strategy for hospitalized patients. Such strategies are difficult to be standardized because certain individuals can have pro-thrombotic conditions, such as inherited thrombophilia, which pre-dispose them to an additional coagulative risk. Whether outside the hospital or when admitted, patients with inherited thrombophilia need special anticoagulant and antiplatelet attention. Identifying such patients, especially in susceptible populations like the eastern Mediterranean (EM) region, will aid primary providers in risk stratification for choosing the optimal anticoagulation or antiplatelet plan.

Pharmacological management of rare coagulation factor deficiencies besides hemophilia

INTRODUCTION

Rare coagulation factor deficiencies are less-known disorders with variable effects on the patient's life. Management of such patients is a challenge due to the paucity of evidence-based data, more so when patients with these rare disorders encounter a more rare, related condition, like inhibitor development or thrombosis.

AREA COVERED

A comprehensive literature search related to RCFDs and management was performed in PubMed in order to discuss therapeutic options and challenges, prophylaxis, management of minor and major surgeries, obstetric and gynecological complications, inhibitor development, and thrombosis.

EXPERT OPINION

Although significant changes have occurred in the management of RCFDs in recent years, more evidence-based studies besides expert opinion are needed for optimal management.

Treatment of rare factor deficiencies other than hemophilia

The deficiency of fibrinogen, prothrombin, factor V (FV), FVII, FVIII, FIX, FX, FXI, and FXIII, called rare coagulation disorders (RCDs), may result in coagulopathies leading to spontaneous or posttrauma and postsurgery hemorrhages. RCDs are characterized by a wide variety of symptoms, from mild to severe, which can vary significantly from 1 disease to another and from 1 patient to another. The most typical symptoms of all RCDs are mucosal bleedings and bleeding at the time of invasive procedures, whereas other life-threatening symptoms such as central nervous system bleeding and hemarthroses are mostly present only in some deficiencies (afibrinogenemia, FX, and FXIII). At variance with hemophilia A and B and von Willebrand disease, RCDs are much less prevalent, ranging from 1 case in 500 000 to 1 in 2 million in the general population. Their clinical heterogeneity associated with the low number of patients has led to a delay in the development of appropriate therapies. Indeed, a similar heterogeneity can also be found in the treatment products available, ranging from the specific recombinant proteins to treat FVII- and FXIII-deficient patients to the complete absence of specific products to treat patients with FII or FV deficiencies, for whom prothrombin complex concentrates or fresh frozen plasma are, to date, the only option. The recent development of novel hemostatic approaches for hemophilia, such as the use of nonsubstitutive therapy as RNA interference, anti-tissue factor pathway inhibitor, and the gene therapy aimed at improving the patient's quality of life may also have an important role in the treatment of patients with RCDs in the future.