Congenital hypofibrinogenemia associated with a novel heterozygous nonsense mutation in the globular C-terminal domain of the γ-chain (p.Glu275Stop)

Dysfibrinogenemia and hypofibrinogenemia - Spectrum of pathogenic variants in Slovak patients

INTRODUCTION

Congenital hypofibrinogenemia (CH) and congenital dysfibrinogenemia (CD) are rare coagulation disorders caused by quantitative or qualitative defects in the fibrinogen gene. The aim of this study was to characterize the genetic background and the clinical manifestations of congenital fibrinogen disorders in the patients from Slovakia registered at the National Haemophilia Centre.

MATERIALS AND METHODS

Results of genetic analysis of the fibrinogen genes FGA, FGB and FGG using polymerase chain reaction followed by direct sequencing were evaluated in 36 patients.

RESULTS

Molecular-genetic analysis revealed six novel variants - FGA c.923_968dup p.(Gly324Lysfs*44) and FGG c.1105C>T p.(His369Tyr) were identified in CD patients. In CH patients, in the FGG gene c.8G>A p.(Trp3*), c.823G>T p.(Glu275*) and c.323C>A p.(Ala108Asp) variants were detected. In the FGB gene c.1427C>T p.(Ser476Leu) was identified.

CONCLUSION

This study is a positive contribution towards expanding knowledge about genetic variants in patients with congenital fibrinogen disorders.

Congenital fibrinogen disorders: a retrospective clinical and genetic analysis of the Prospective Rare Bleeding Disorders Database

ABSTRACT

Congenital fibrinogen deficiency (CFD) is a rare bleeding disorder caused by mutations in FGA, FGB, and FGG. We sought to comprehensively characterize patients with CFD using PRO-RBDD (Prospective Rare Bleeding Disorders Database). Clinical phenotypes, laboratory, and genetic features were investigated using retrospective data from the PRO-RBDD. Patients were classified from asymptomatic to grade 3 based on their bleeding severity. In addition, FGA, FGB, and FGG were sequenced to find causative variants. A total of 166 CFD cases from 16 countries were included, of whom 123 (30 afibrinogenemia, 33 hypofibrinogenemia, 55 dysfibrinogenemia, and 5 hypodysfibrinogenemia) were well characterized. Considering the previously established factor activity and antigen level thresholds, bleeding severity was correctly identified in 58% of the cases. The rates of thrombotic events among afibrinogenemic and hypofibrinogenemic patients were relatively similar (11% and 10%, respectively) and surprisingly higher than in dysfibrinogenemic cases. The rate of spontaneous abortions among 68 pregnancies was 31%, including 86% in dysfibrinogenemic women and 14% with hypofibrinogenemia. Eighty-six patients received treatment (69 on-demand and/or 17 on prophylaxis), with fibrinogen concentrates being the most frequently used product. Genetic analysis was available for 91 cases and 41 distinct variants were identified. Hotspot variants (FGG, p.Arg301Cys/His and FGA, p.Arg35Cys/His) were present in 51% of dysfibrinogenemia. Obstetric complications were commonly observed in dysfibrinogenemia. This large multicenter study provided a comprehensive insight into the clinical, laboratory, and genetic history of patients with CFDs. We conclude that bleeding severity grades were in agreement with the established factor activity threshold in nearly half of the cases with quantitative defects.

User Perceptions of ROTEM-Guided Haemostatic Resuscitation: A Mixed Qualitative-Quantitative Study

Viscoelastic point-of-care haemostatic resuscitation methods, such as ROTEM or TEG, are crucial in deciding on time-efficient personalised coagulation interventions. International transfusion guidelines emphasise increased patient safety and reduced treatment costs. We analysed care providers' perceptions of ROTEM to identify perceived strengths and areas for improvement. We conducted a single-centre, mixed qualitative-quantitative study consisting of interviews followed by an online survey. Using a template approach, we first identified themes in the responses given by care providers about ROTEM. Later, the participants rated six statements based on the identified themes on five-point Likert scales in an online questionnaire. Seventy-seven participants were interviewed, and 52 completed the online survey. By analysing user perceptions, we identified ten themes. The most common positive theme was "high accuracy". The most common negative theme was "need for training". In the online survey, 94% of participants agreed that monitoring the real-time ROTEM temograms helps to initiate targeted treatment more quickly and 81% agreed that recurrent ROTEM training would be beneficial. Anaesthesia care providers found ROTEM to be accurate and quickly available to support decision-making in dynamic and complex haemostatic situations. However, clinicians identified that interpreting ROTEM is a complex and cognitively demanding task that requires significant training needs.

Thrombosis-associated hypofibrinogenemia: novel abnormal fibrinogen variant FGG c.8G>A with oxidative posttranslational modifications

Here, we present the first case of fibrinogen variant FGG c.8G>A. We investigated the behaviour of this mutated fibrinogen in blood coagulation using fibrin polymerization, fibrinolysis, fibrinopeptides release measurement, mass spectrometry (MS), and scanning electron microscopy (SEM). The case was identified by routine coagulation testing of a 34-year-old man diagnosed with thrombosis. Initial genetic analysis revealed a heterozygous mutation in exon 1 of the FGG gene encoding gamma chain signal peptide. Fibrin polymerization by thrombin and reptilase showed the normal formation of the fibrin clot. However, maximal absorbance within polymerization was lower and fibrinolysis had a longer degradation phase than healthy control. SEM revealed a significant difference in clot structure of the patient, and interestingly, MS detected several posttranslational oxidations of fibrinogen. The data suggest that the mutation FGG c.8G>A with the combination of the effect of posttranslational modifications causes a novel case of hypofibrinogenemia associated with thrombosis.

Heterogeneity of Genotype–Phenotype in Congenital Hypofibrinogenemia—A Review of Case Reports Associated with Bleeding and Thrombosis

Congenital fibrinogen disorders are diseases associated with a bleeding tendency; however, there are also reports of thrombotic events. Fibrinogen plays a role in the pathogenesis of thrombosis due to altered plasma concentrations or modifications to fibrinogen’s structural properties, which affect clot permeability, resistance to lysis, and its stiffness. Several distinct types of genetic change and pathogenetic mechanism have been described in patients with bleeding and a thrombotic phenotype, including mutations affecting synthesis or processing in three fibrinogen genes. In this paper, we focused on familial hypofibrinogenemia, a rare inherited quantitative fibrinogen disorder characterized by decreased fibrinogen levels with a high phenotypic heterogeneity. To begin, we briefly review the basic information regarding fibrinogen’s structure, its function, and the clinical consequences of low fibrinogen levels. Thereafter, we introduce 15 case reports with various gene mutations derived from the fibrinogen mutation database GFHT (French Study Group on Hemostasis and Thrombosis), which are associated with congenital hypofibrinogenemia with both bleeding and thrombosis. Predicting clinical presentations based on genotype data is difficult. Genotype–phenotype correlations would be of help to better understand the pathologic properties of this rare disease and to provide a valuable tool for the identification of patients who are not only at risk of bleeding, but also at risk of a thrombotic event.

Assessment of Risk Factors and Cognitive Level Associated with Venous Thrombosis Patients in a Coexistence of Multiple Diseases Study in Shanghai

Background

Venous thrombosis (VTE) is a high-incidence disease that affects different systems of the body, but no comparative studies have been conducted to explore its incidence in different systems in patients with the coexistence of multiple diseases. Primary care is a medical institution that has the first contact with patients’ conditions. The majority of outpatients suffer from multiple diseases, and they are more prone to VTE, which is of significance and requires investigation. At the same time, we observed that the primary care patients’ cognition level of VTE is insufficiency at present, and the prevention and management of VTE in China is still in its infancy. Most studies focus on whether doctors and nurses are clear about the diagnosis and manifestations of VTE, however, few studies on patients’ cognitive level and influencing factors of symptoms and prevention of VTE. Therefore, it is necessary to study the causes of cognitive deficiency of VTE from the perspective of patients, conduct targeted cognitive and behavioral interventions, and finally achieve the purpose of improving the effect of VTE prevention and management.

Aim

This study aimed to explore the risk factors, cognitive level and cognitive potential influence factors of VTE in outpatients of primary care in Shanghai, as well as which diseases, are more likely to promote occurrence of VTE among patients with multiple diseases.

Methods

A total of 710 patients were included in the analysis. Shanghai in China is divided into urban and suburban areas by their geographical location, and a random sample of 10 primary care areas was investigated, including 5 urban areas and 5 suburban areas. The Padua scale and the VTE cognitive level-related knowledge test scale were used for the investigation. Statistical software was used to conduct univariate Pearson correlation analysis and multivariate logistic regression analysis for VTE high-risk factors among outpatients of primary care. Furthermore, the high-risk factors for VTE and the types of chronic disease in patients with multiple diseases were subjected to subgroup analyses. t-test was used to statistically analyze cognitive level of VTE and the potential influence factors related to the patients’ VTE cognitive level.

Results

Univariate analysis of risk factors for VTE in 710 outpatients showed that age (χ²=83.895, P<0.001), education (χ²=8.324, P=0.004), region (χ²=63.936, P<0.001), chronic disease (χ²=18.198, P<0.001) and the coexistence of multiple diseases (χ²=61.347, P<0.001) were the main risk factors for VTE risk in patients. Logistic multivariate regression analysis showed that age, region, chronic diseases and the coexistence of multiple diseases were independent risk factors for VTE risk in patients. The correlation between high risk of VTE in patients with multiple diseases and various types of chronic diseases was further analyzed by logistic multivariate regression. The results showed that diabetes mellitus (OR=1.636 [95% CI, 1.030–2.599], P=0.037), cerebral infarction (OR=8.484 [95% CI, 4.615–15.597], P<0.001), coronary heart disease (OR=2.987 [95% CI, 1.699–5.252], P<0.001), intracerebral hemorrhage (OR=15.130 [95% CI, 4.707–48.630], P<0.001), respiratory diseases (OR=3.470, [95% CI, 1.428–8.43], P=0.006) and malignant tumors (OR=4.576, [95% CI, 1.85–11.315], P=0.001) were independent risk factors for VTE among patients with co-existing diseases, and the risks from high to low were cerebral hemorrhage>cerebral infarction>malignant tumor>respiratory system disease>coronary heart disease> diabetes. In addition, patients’ age (t=6.869, P<0.001), region (t=3.420, P<0.001), education level (t=−7.341, P<0.001), chronic disease (t=5.875, P<0.001), BMI (t=6.404, P=0.012), smoking (t=4.152, P=0.042) were related to the VTE cognitive level.

Conclusion

General practitioners should pay close attention to independent risk factors for VTE among patients in routine outpatient care, especially patients with co-existing diseases with independent risk for VTE, placing them high risk of VTE. At the same time, health education and other measures should be strengthened to improve the patients’ awareness and cognitive level of VTE to prevent the occurrence of VTE and its related complications.

Mutations Accounting for Congenital Fibrinogen Disorders: An Update

Fibrinogen is a complex protein that plays a key role in the blood clotting process. It is a hexamer composed of two copies of three distinct chains: Aα, Bβ, and γ encoded by three genes, FGA, FGB, and FGG, clustered on the long arm of chromosome 4. Congenital fibrinogen disorders (CFDs) are divided into qualitative deficiencies (dysfibrinogenemia, hypodysfibrinogenemia) in which the mutant fibrinogen molecule is present in the circulation and quantitative deficiencies (afibrinogenemia, hypofibrinogenemia) with no mutant molecule present in the bloodstream. Phenotypic manifestations are variable, patients may be asymptomatic, or suffer from bleeding or thrombosis. Causative mutations can occur in any of the three fibrinogen genes and can affect one or both alleles. Given the large number of studies reporting on novel causative mutations for CFDs since the review on the same topic published in 2016, we performed an extensive search of the literature and list here 120 additional mutations described in both quantitative and qualitative disorders. The visualization of causative single nucleotide variations placed on the coding sequences of FGA, FGB, and FGG reveals important structure function insight for several domains of the fibrinogen molecule.

Fibrinogen and Atherosclerotic Cardiovascular Diseases-Review of the Literature and Clinical Studies

Atherosclerotic cardiovascular diseases (ASCVD), including coronary artery disease, cerebrovascular disease, and peripheral arterial disease, represent a significant cause of premature death worldwide. Biomarkers, the evaluation of which would allow the detection of ASCVD at the earliest stage of development, are intensively sought. Moreover, from a clinical point of view, a valuable biomarker should also enable the assessment of the patient’s prognosis. It has been known for many years that the concentration of fibrinogen in plasma increases, inter alia, in patients with ASCVD. On the one hand, an increased plasma fibrinogen concentration may be the cause of the development of atherosclerotic lesions (increased risk of atherothrombosis); on the other hand, it may be a biomarker of ASCVD, as it is an acute phase protein. In addition, a number of genetic polymorphisms and post-translational modifications of fibrinogen were demonstrated that may contribute to the risk of ASCVD. This review summarizes the current data on the importance of fibrinogen as a biomarker of ASCVD, and also presents the relationship between molecular modifications of this protein in the context of ASCVD.

Congenital Afibrinogenemia and Hypofibrinogenemia: Laboratory and Genetic Testing in Rare Bleeding Disorders with Life-Threatening Clinical Manifestations and Challenging Management

Congenital fibrinogen disorders are rare pathologies of the hemostasis, comprising quantitative (afibrinogenemia, hypofibrinogenemia) and qualitative (dysfibrinogenemia and hypodysfibrinogenemia) disorders. The clinical phenotype is highly heterogeneous, being associated with bleeding, thrombosis, or absence of symptoms. Afibrinogenemia and hypofibrinogenemia are the consequence of mutations in the homozygous, heterozygous, or compound heterozygous state in one of three genes encoding the fibrinogen chains, which can affect the synthesis, assembly, intracellular processing, stability, or secretion of fibrinogen. In addition to standard coagulation tests depending on the formation of fibrin, diagnostics also includes global coagulation assays, which are effective in monitoring the management of replacement therapy. Genetic testing is a key point for confirming the clinical diagnosis. The identification of the precise genetic mutations of congenital fibrinogen disorders is of value to permit early testing of other at risk persons and better understand the correlation between clinical phenotype and genotype. Management of patients with afibrinogenemia is particularly challenging since there are no data from evidence-based medicine studies. Fibrinogen concentrate is used to treat bleeding, whereas for the treatment of thrombotic complications, administered low-molecular-weight heparin is most often. This review deals with updated information about afibrinogenemia and hypofibrinogenemia, contributing to the early diagnosis and effective treatment of these disorders.

Viscoelastic Testing and Coagulopathy of Traumatic Brain Injury

A unique coagulopathy often manifests following traumatic brain injury, leading the clinician down a difficult decision path on appropriate prophylaxis and therapy. Conventional coagulation assays—such as prothrombin time, partial thromboplastin time, and international normalized ratio—have historically been utilized to assess hemostasis and guide treatment following traumatic brain injury. However, these plasma-based assays alone often lack the sensitivity to diagnose and adequately treat coagulopathy associated with traumatic brain injury. Here, we review the whole blood coagulation assays termed viscoelastic tests and their use in traumatic brain injury. Modified viscoelastic tests with platelet function assays have helped elucidate the underlying pathophysiology and guide clinical decisions in a goal-directed fashion. Platelet dysfunction appears to underlie most coagulopathies in this patient population, particularly at the adenosine diphosphate and/or arachidonic acid receptors. Future research will focus not only on the utility of viscoelastic tests in diagnosing coagulopathy in traumatic brain injury, but also on better defining the use of these tests as evidence-based and/or precision-based tools to improve patient outcomes.

Progression of Fibrinogen Decrease during High Dose Tigecycline Therapy in Critically Ill Patients: A Retrospective Analysis

Tigecycline is a novel glycylcycline broad-spectrum antibiotic offering good coverage for critically ill patients experiencing complicated infections. A known side effect is a coagulation disorder with distinct hypofibrinogenemia. To date, the information on possible risk factors and outcomes is sparse. Therefore, the aim of this study is to examine the time course of fibrinogen level changes during tigecycline therapy in critically ill patients. Moreover, we sought to identify risk factors for coagulopathy and to report on clinically important outcomes. We retrospectively reviewed all intensive care patients admitted to our General and Surgical Intensive Care Unit receiving tigecycline between 2010 and 2018. A total of 130 patients were stratified into two groups based on the extent of fibrinogen decrease. Patients with a greater fibrinogen decrease received a higher dose, a longer treatment and more dose changes of tigecycline, respectively. In regard to the underlying pathology, these patients showed higher inflammation markers as well as a slightly reduced liver synthesis capacity. We, therefore, conclude that such a fibrinogen decrease may be based upon further impairment of liver synthesis during severe inflammatory states. To decrease the risk of bleeding, cautious monitoring of coagulation in critically ill patients treated with high-dose tigecycline is warranted.

Antithrombotic Therapy in Patients with Peripheral Artery Disease: A Focused Review on Oral Anticoagulation

Peripheral artery disease (PAD) is a major cause of morbidity and mortality but it is usually underdiagnosed and undertreated. Patients with PAD present dysregulated procoagulant, anticoagulant, and fibrinolytic pathways leading to arterial and venous thrombosis. The risk of several ischemic-related complications could be mitigated with appropriate antithrombotic therapy, which plays a central role in all types of PAD. For years, antiplatelets have been indicated in patients with symptomatic PAD or those who have undergone revascularization. Unfortunately, a non-negligible proportion of patients with PAD will suffer from adverse events during the follow-up, even despite proper medical therapies for the prevention of PAD complications. Thus, there is room for improving clinical outcomes in these patients. Given the implication of both, primary and secondary hemostasis in arterial thrombosis and the pathophysiology of PAD, the combination of antiplatelets and anticoagulants has emerged as a potential antithrombotic alternative to antiplatelets alone. In this narrative review article, we have highlighted the most recent evidence about antithrombotic therapy in PAD patients, with a special focus on oral anticoagulation. Certainly, COMPASS and VOYAGER PAD trials have shown promising results. Thus, rivaroxaban in combination with aspirin seem to reduce cardiovascular outcomes with a similar bleeding risk compared to aspirin alone. Nevertheless, results from real-world studies are needed to confirm these observations, and other trials will provide novel evidence about the safety and efficacy of emerging anticoagulant agents.

Clinical and molecular characterization of Iranian patients with congenital fibrinogen disorders

INTRODUCTION

Congenital fibrinogen disorders (CFDs) are caused by mutations in the FGA, FGB and FGG genes and are classified as quantitative and qualitative fibrinogen defects. This study sought to determine the genetic background of CFDs in Iran and to examine the genotype-phenotype correlation.

METHODS

Fourteen patients with a CFD diagnosis were included. Fibrinogen antigen and activity were measured by the immunoturbidimetric and Clauss methods respectively. Gene sequencing was performed following a polymerase chain reaction amplification of fibrinogen's genes. The ISTH Bleeding Assessment Tool was also evaluated for all cases.

RESULTS

Patients were diagnosed with dysfibrinogenemia (n = 10), hypodysfibrinogenemia (n = 2) and afibrinogenemia (n = 2). Seven different mutations located on FGA exon 2 (57 %), exon 4 (7%), exon 5 (7%) and FGG exon 8 (29 %) were identified. In patients with qualitative deficiencies, mutations were including p.Arg38Thr, p.Arg35His, p.Arg35Cys, p.Val145Asp, and p.Arg301Cys and were including p.Gly316GlufsX105 and p.Trp52stop in afibrinogenemic patients. In dysfibrinogenemia, two hotspot mutations, FGA Arg35 and FGG Arg301 were identified in 60 % of patients and the remaining (40 %) had p.Arg38Thr mutation. The p.Val145Asp and two hotspot mutations, p.Arg35His, p.Arg35Cys, were identified for the first time in Iran. The overall median (range) bleeding score (BS) was 4 (0-6) in all patients and it was 3.5 (0-5) in dysfibrinogenemia. Cutaneous bleeding and menorrhagia were the most common bleeding manifestations.

CONCLUSION

There was a weak genotype-phenotype correlation in CFDs and patients with dysfibrinogenemia were more symptomatic than in previous studies. Despite ethnic's differences, the prevalence of hotspot mutations in dysfibrinogenemia was similar to the other studies.

Fibrin(ogen) as a Therapeutic Target: Opportunities and Challenges

Fibrinogen is one of the key molecular players in haemostasis. Thrombin-mediated release of fibrinopeptides from fibrinogen converts this soluble protein into a network of fibrin fibres that form a building block for blood clots. Thrombin-activated factor XIII further crosslinks the fibrin fibres and incorporates antifibrinolytic proteins into the network, thus stabilising the clot. The conversion of fibrinogen to fibrin also exposes binding sites for fibrinolytic proteins to limit clot formation and avoid unwanted extension of the fibrin fibres. Altered clot structure and/or incorporation of antifibrinolytic proteins into fibrin networks disturbs the delicate equilibrium between clot formation and lysis, resulting in either unstable clots (predisposing to bleeding events) or persistent clots that are resistant to lysis (increasing risk of thrombosis). In this review, we discuss the factors responsible for alterations in fibrin(ogen) that can modulate clot stability, in turn predisposing to abnormal haemostasis. We also explore the mechanistic pathways that may allow the use of fibrinogen as a potential therapeutic target to treat vascular thrombosis or bleeding disorders. Better understanding of fibrinogen function will help to devise future effective and safe therapies to modulate thrombosis and bleeding risk, while maintaining the fine balance between clot formation and lysis.

Congenital dysfibrinogenemia caused by γAla327Val mutation: structural abnormality of D region

BACKGROUND

: Congenital dysfibrinogenemia (CD) is a coagulation disorder caused by mutations in the fibrinogen genes, which result in abnormal fibrinogen function. However, the precise pathogenesis underlying it remains unclear.

METHODS

: In this study, we identified a novel heterozygous mutation in an asymptomatic patient with CD caused by γ Ala327Val mutation. Aimed to investigate the pathogenesis, functional studies of fibrinogen isolated from the proband and her family members were performed, such as coagulation function, fibrinogen aggregation test, and fibrin clot lysis test. Coagulation was monitored using a thromboelastometer, and the fibrin clot network structure was observed by scanning electron microscopy. The effect of the mutation on fibrinogen structure and function was predicted by molecular modeling.

RESULTS

: The fibrinogen activity concentration in patients with CD was significantly lower than that in healthy individuals, indicating that fibrinogen activity was low. Proband's fibrinogen activity concentration was 0.75 g/L(Clauss method) and antigen concentration (immune turbidimetry method) was 1.59 g/L(normal reference range for both parameters: 2.0-4.0 g/L). Thromboelastography showed that the K value of patients with CD was higher than that of healthy individuals and Angle values were decreased, indicating that mutation impaired fibrinogen function. Compared to fibrinogen from healthy individuals, fiber network structure of the proband was loose, pore size was increased, and fiber branch nodes were increased.

CONCLUSIONS

: Ala327Val heterozygous missense mutation leads to changes in the structure of fibrinogen D region and impairs the aggregation function of fibrinogen. This mutation is reported here for the first time.

Congenital dysfibrinogenaemia presented with preterm premature rupture of the membranes and vaginal bleeding

A 26-year-old woman was found to have congenital dysfibrinogenaemia after presenting to our hospital with premature rupture of the membranes and vaginal bleeding. Given the absence of clear guidelines for the management of pregnancy complicated by dysfibrinogenaemia, we followed expert consensus that exists among published works, with some modifications. This case was managed by a multidisciplinary team of obstetrics-gynaecology, haematology and paediatric haematology. Here we review how the patient presented, the investigations that led to the diagnosis and the treatment options.

Genetic Variants in the FGB and FGG Genes Mapping in the Beta and Gamma Nodules of the Fibrinogen Molecule in Congenital Quantitative Fibrinogen Disorders Associated with a Thrombotic Phenotype

Fibrinogen is a hexameric plasmatic glycoprotein composed of pairs of three chains (Aα, Bβ, and γ), which play an essential role in hemostasis. Conversion of fibrinogen to insoluble polymer fibrin gives structural stability, strength, and adhesive surfaces for growing blood clots. Equally important, the exposure of its non-substrate thrombin-binding sites after fibrin clot formation promotes antithrombotic properties. Fibrinogen and fibrin have a major role in multiple biological processes in addition to hemostasis and thrombosis, i.e., fibrinolysis (during which the fibrin clot is broken down), matrix physiology (by interacting with factor XIII, plasminogen, vitronectin, and fibronectin), wound healing, inflammation, infection, cell interaction, angiogenesis, tumour growth, and metastasis. Congenital fibrinogen deficiencies are rare bleeding disorders, characterized by extensive genetic heterogeneity in all the three genes: FGA, FGB, and FGG (enconding the Aα, Bβ, and γ chain, respectively). Depending on the type and site of mutations, congenital defects of fibrinogen can result in variable clinical manifestations, which range from asymptomatic conditions to the life-threatening bleeds or even thromboembolic events. In this manuscript, we will briefly review the main pathogenic mechanisms and risk factors leading to thrombosis, and we will specifically focus on molecular mechanisms associated with mutations in the C-terminal end of the beta and gamma chains, which are often responsible for cases of congenital afibrinogenemia and hypofibrinogenemia associated with thrombotic manifestations.

Women With Congenital Hypofibrinogenemia/Afibrinogenemia: From Birth to Death

Congenital fibrinogen disorders are a group of most frequent rare coagulation disorder, characterized by deficiency and/or defects in the fibrinogen molecule. Quantitative disorders include hypofibrinogenemia and afibrinogenemia. Due to their specific physiological characteristics, female patients tend to have congenital hypofibrinogenemia/afibrinogenemia, such as spontaneous recurrent abortion, menorrhagia, infertility, antepartum and postpartum hemorrhage, and so on. Current studies of congenital hypofibrinogenemia/afibrinogenemia mainly focus on different types of fibrinogen mutations, etiology/pathogenesis, and some rare case reports of the diseases. So far, there is no study available to systematically review the specific features of female patients with congenital bleeding disorders. This review aims to deal with hematological, gynecologic and obstetric issues, and relevant clinical management of congenital hypofibrinogenemia/afibrinogenemia at different life stages of female patients. We believe this review provides valuable reference for clinicians in the field of hematology, obstetrics, as well as gynecology.