Factor VII Deficiency

[How to interpret and pursue a prolonged quick time or APTT]

The standard hemostasis workup [quick time (QT), and activated partial thrombin time (APTT)] is very commonly prescribed but its interpretation is often difficult for practitioners who are not specialized in hemostasis. Here, we review the principles of the diagnostic approach to these tests. Only a very basic knowledge of the coagulation cascade is necessary to identify which clotting factor tests to prescribe and to interpret the results. Deficiency in several clotting factors suggests liver dysfunction, disseminated intravascular coagulation (DIC) or vitamin K deficiency. If a single factor is deficient, we review the different causes of acquired deficiencies and briefly discuss the characteristics of the different congenital defects, which generally require specialized management. Lupus anticoagulant is a common and generally benign cause of prolonged APTT to be aware of, which is not related to a hemorrhagic risk. A good knowledge of the diagnostic approach to abnormal QT or APTT generally allows the resolution of the most common situations.

The identification of a novel compound heterozygous mutation in hereditary human coagulation factor VII deficiency following a bamboo leaf green snake bite

Hereditary factor VII (FVII) deficiency is an uncommon autosomal recessive disorder associated with mutations in the F7 gene, and laboratory investigations usually reveal isolated prolongation in prothrombin time (PT)/international normalized ratio (INR). Venom-induced consumptive coagulopathy (VICC) is distinguished by the activation of the coagulation pathway, which is triggered by procoagulant toxins in snake venom. Diagnosing snakebites in patients with hereditary FVII deficiency presents a challenge because prolonged time PT/INR is considered the most valuable diagnostic method for VICC. Therefore, it is possible that certain patients may not promptly receive an accurate diagnosis of hereditary FVII deficiency. We present a pedigree featuring hereditary FVII deficiency, which was diagnosed through Sanger sequencing, following a bamboo leaf green snake bite.

Genetic Landscape of Factor VII Deficiency: Insights from a Comprehensive Analysis of Pathogenic Variants and Their Impact on Coagulation Activity

Congenital factor VII (FVII) deficiency is a rare genetic bleeding disorder characterized by deficient or reduced activity of coagulation FVII. It is caused by genetic variants in the F7 gene. We aimed to evaluate the rate of detection of pathogenic variants in the F7 gene in a large group of patients with FVII deficiency and investigate the correlations between the F7 genotype and FVII activity (FVII:C). Moreover, the influence of the common genetic variant rs6046: c.1238G>A; p.(Arg413Gln), designated as the M2 allele, on FVII:C was investigated. Genetic analysis of the F7 gene was performed on 704 index patients (IPs) using either direct Sanger- or next-generation sequencing. Genetic variants were detected in 390 IPs, yielding a variant detection rate (VDR) of 55%. Notably, the VDR exhibited a linear decline with increasing FVII:C levels. We identified 124 genetic variants, of which 48 were not previously reported. Overall, the frequency of the M2 allele was considerably higher in patients with mild deficiency (FVII:C > 20 IU/dl). Furthermore, IPs lacking an identified pathogenic variant exhibited a significantly higher prevalence of the M2 allele (69%) compared to IPs with a disease-causing variant (47%). These results strongly support the association of the M2 allele with decreased FVII:C levels. This study shows the utility of FVII:C as a predictive marker for identifying pathogenic variants in patients with FVII deficiency. The M2 allele contributes to the reduction of FVII:C levels, particularly in cases of mild deficiency.

Site-directed mutagenesis of tissue factor pathway inhibitor-binding exosite D60A on factor VII results in a new factor VII variant with lower coagulant activity

Background

Recombinant factor (F)VIIa (rFVIIa) has been approved by the US Food and Drug Administration for the treatment of hemophilia A and B with inhibitors and congenital FVII deficiency. Moreover, the investigational uses of rFVIIa are becoming of interest since it can be used to treat various clinical bleeding conditions. However, there is evidence showing that rFVIIa is a potent procoagulant agent that potentially leads to an increased risk of thrombotic complications.

Objectives

To design a new rFVII with lower coagulant activity that could potentially be used as an alternative hemostatic agent aiming to minimize the risk of thrombogenicity.

Methods

D60A was introduced into the F7 sequence by polymerase chain reaction-based mutagenesis. Wild type (WT) and D60A were generated in human embryonic kidney 293T cells by stable transfection. FVII coagulant activities were determined by amidolytic cleavage of the FVIIa-specific substrate, 2-step FXa generation, thrombin generation (TG), and clot-based assays.

Results

WT and D60A demonstrated similar FVIIa amidolytic activity. However, D60A showed approximately 50% activity on FX activation and significantly longer lag time in the TG assay than that shown by WT. The clotting time produced by D60A spiked in FVII-deficient plasma was significantly prolonged than that of WT. Additionally, the ex vivo plasma half-lives of WT and D60A were comparable.

Conclusion

D60A demonstrated lower coagulant activities, most likely due to the weakening of FX binding, leading to impaired FX activation and delayed TG and fibrin formation. Considering that a plasma FVII level of 15% to 25% is adequate for normal hemostasis, D60A is a molecule of interest for future development of an rFVII with a lesser extent of thrombogenicity.

Acquired Factor VIII Deficiency in Chronic Myeloid Leukemia: A Case Report

Factor VIII deficiency is mostly seen in hemophilia A, an X-linked recessive disorder. Patients would have a past medical history of bleeding diathesis or a family history of bleeding disorder. Acquired deficiencies of factor VIII are rare; some cases have been reported in solid malignancies. We present this case of acquired factor VIII deficiency in chronic myeloid leukemia (CML). A 72-year-old man was incidentally found to have leukocytosis at 31,000 and a platelet count of 3.2 million on a routine complete blood count (CBC). Prothrombin time (PT), international normalized ratio (INR), and partial thromboplastin time (PTT) showed an isolated elevation of PTT at 38.1 and a low factor VIII activity level at 39. The patient did not have any history or physical examination suggestive of bleeding diathesis. A bone marrow biopsy confirmed the BCR/ABL mutation, a diagnosis of CML was made, and the patient was started on dasatinib for one month. His PTT normalized after treatment for CML, suggesting a deficiency of factor VIII likely related to CML. The aim of this study is to highlight a case with acquired factor VIII deficiency due to CML and to emphasize the importance of coagulation workup in all newly diagnosed CML patients.

Acquired Isolated Factor VII Deficiency in Plasma Cell Dyscrasias: A Brief Presentation of Two Plasma-Cell-Leukemia-Related Cases and Review of Literature

Acquired isolated factor VII (FVII) deficiency is a rare but important discovery in patients with plasma cell disorders with significant therapeutic and prognostic implications. The present analysis and review of cases reported in the literature is intended to highlight disease-related characteristics associated with this rare clotting defect, clinical manifestations and outcome, and potential underlying mechanisms, and to provide guidance on how to manage these patients in terms of prophylactic and therapeutic measures. The discovery of acquired FVII deficiency in a patient with multiple myeloma (MM) or monoclonal gammopathy of uncertain significance (MGUS) should prompt an evaluation for AL amyloidosis, particularly for amyloid hepatosplenic involvement, whenever not previously documented. Acquired FVII deficiency in patients with MM and AL amyloidosis is frequently associated with severe bleeding diathesis, also related to a number of concomitant predisposing factors, adversely affecting the outcome. The prompt institution of a rapidly acting therapy is crucial to prevent severe bleeding complications and positively impact outcome. Recombinant activated factor VII (rVIIa) may represent a useful supportive care measure, both in treating active bleeding and in the peri-procedural setting. However, further clinical experience is needed to optimize the therapeutic management of this rare disorder.

Factor VII deficiency: a rare genetic bleeding disorder in a 7-year-old child: a case report

BACKGROUND

Factor VII deficiency is a rare inherited bleeding disorder that has similar clinical presentation to hemophilia.

CASE REPORT

A 7-year-old male child of African origin experienced recurrent nasal bleeding since 3 years of age and recurrent swelling of the joints that was remarkable at the age of 5-6 years. He received multiple blood transfusions and has been managed as a patient with hemophilia until he presented to our facility. Reviewed evaluation of the patient revealed abnormal prothrombin and normal activated partial thromboplastin time, FVII analysis showed activity level of less than 1%, and the diagnosis of FVII deficiency was made. The patient was treated with fresh frozen plasma, vitamin K injection, and tranexamic tablets.

CONCLUSION

Even though factor VII deficiency is an extremely rare bleeding disorder, it does occur in our setting. This case highlights the need for clinicians to consider this condition when faced with challenging patients presenting with bleeding disorders.

Molecular spectrum of inherited FVII deficiency in North India revealed a recurrent variant with a founder effect

INTRODUCTION

Inherited Factor VII (FVII) deficiency is commonest among the rare bleeding disorders. A small number of patients present in infancy with severe bleeding, and many may remain asymptomatic but detected before surgery/invasive procedures. Genetic testing may be helpful in predictive testing/prenatal diagnosis in severe cases.

AIM

Characterisation of clinical and genotypic spectrum of patients with inherited FVII deficiency.

METHODS

Retro-prospectively, 35 cases with prolonged prothrombin time and FVII activity (FVII:C) <50 IU/dl were subjected to targeted resequencing. After in-silico analysis, variant/s were validated by Sanger sequencing in index cases and family members. Haplotype analysis was done for F7 polymorphisms.

RESULTS

Severe FVII deficiency was found in 50% of patients (FVII:C ≤1 IU/dl), and 42.9% were asymptomatic. Clinical severity assessment revealed 17% severe, 17% moderate and 22.9% patients with mild bleeds. FVII levels ranged from .3 to 38 IU/dl. Molecular analysis revealed variants in 30/35 cases, of which 17 were homozygous, 10 were compound heterozygous and 3 were heterozygous. Twelve genetic variants were identified, one promoter variant c.-30A>C; seven missense (c.215C>G, c.244T>C, c.253G>C, c.904G>A, c.961C>T, c.1109G>T, c.1211G>A), two deletions (c.21delG, c.868_870delATC), and one each of nonsense c.634C>T and splice-site variant c.316+1G>A. Recurrent variants c.1109G>T and c.215C>G were found in 17 and 8 cases, 12 of the former cases were homozygous. They had the same haplotype, indicating the founder effect in North Indians.

CONCLUSION

This is the largest cohort of FVII genotyping from India, confirming heterogeneity in terms of clinical manifestations, FVII activity and zygosity of the variants with a limited genotypic phenotypic correlation.

Investigation of a common canine factor VII deficiency variant in dogs with unexplained bleeding on autopsy

The factor VII (FVII) protein is an integral component of the extrinsic coagulation pathway. Deleterious variants in the gene encoding this protein can result in factor VII deficiency (FVIID), a bleeding disorder characterized by abnormal (slowed) clotting with a wide range of severity, from asymptomatic to life-threatening. In canids, a single FVIID-associated variant, first described in Beagles, has been observed in 24 breeds and mixed-breed dogs. Because this variant is present in breeds of diverse backgrounds, we hypothesized that it could be a contributing factor to unexplained bleeding observed in some canine autopsy cases. DNA was extracted from paraffin-embedded tissue samples from 67 anticoagulant-negative autopsy cases with unexplained etiology for gross lesions of hemorrhage. Each dog was genotyped for the c.407G>A (F71) variant. Experimental controls included 3 known heterozygotes and 2 known homozygotes for the F71 variant, 2 normal dogs with known homozygous wild-type genotypes (F7WF7W), and 5 dogs with bleeding at autopsy that tested positive for anticoagulant rodenticide and were genotyped as F7WF7W. All 67 cases tested homozygous for the wild-type allele, indicating that the common FVIID variant was not responsible for the observed unexplained bleeding. Our work demonstrates the usefulness of retrospective studies utilizing veterinary diagnostic laboratory databases and tissue archives for genetic studies. In the case of FVIID, our results suggest that a singular molecular test for the F71 variant is not a high-yield addition to postmortem screening in these scenarios.

Thromboelastometry as an Ancillary Tool for Evaluation of Coagulation Status after rFVIIa Therapy in a Pregnant Woman with Severe Hypoproconvertinemia-A Case Series and Review of the Literature

Introduction: Factor VII (FVII) deficiency is a rare hemorrhagic diathesis. In females, heavy menstrual and postpartum bleeding can appear as a consequence of its deficiency. Supplementation of the recombinant FVIIa is widely accepted. The supplementation effect in FVII-deficient subjects is difficult to predict, and severe hemorrhage has been described even when FVII levels after supplementation were within normal ranges. The aim of this report is to present the application of thromboelastometry to control the coagulation status in a patient with severe FVII deficiency during pregnancy and delivery, supplemented by rFVIIa per protocol complicated with life-threatening venous thromboembolism. Methods: Rotational thromboelastometry (ROTEM) was performed in 16 pregnant women: in one 28 year old primigravida at 35 weeks of pregnancy with congenital FVII deficiency after rFVIIa administration and 15 healthy women at 38 gestational weeks. The results were compared. Results: The thromboelastometry results showed significant shortening of the clotting time in the extrinsic and the intrinsic pathway in the hypoproconvertinemia patient after rFVIIa administration in relation to healthy pregnant women. A significant reduction in maximum lysis of the clot after FVII supplementation was observed. Conclusions: The thromboelastometry results showed a significant hypercoagulable state with hypoproconvertinemia. Thrombotic complications after delivery might be prevented by the reduction in rFVIIa guided by thromboelastometry. Thromboelastometry performed on a pregnant woman with factor VII deficiency during the supplementation of rFVIIa in peripartum time might be helpful in order to determine an individual, effective dosage regimen of rFVIIa to ensure full correction of clotting disorders without the tendency to develop thrombosis, but further studies are needed.

Clinical phenotype and F7 gene genotype in 40 Tunisian patients with congenital factor VII deficiency

Congenital factor VII (FVII) deficiency is an autosomal recessive bleeding disorder characterized by a weak phenotypic and genotypic correlation. This study aimed to determine the genetic alterations of 40 Tunisian patients and to evaluate their relationships with the collected clinical and biological data. Forty FVII-deficient Tunisian patients have been included in this study. First, diagnosis of the FVII deficiency was made on the basis of FVII coagulant activity (FVII:c) levels performed using the prothrombin time assay. Then, clinical and anamnesis data were set up and filed out from the regional registry of bleeding disorders and the medical file of each patient. Finally, genetic alterations were determined by direct sequencing of the coding regions, intron/exons boundaries of the F7 gene. Clinical heterogeneity was noticed, and the direct sequencing allowed the identification of 13 F7 gene mutations of which one was a novel mutation. The clinical manifestations are variably associated with FVII activity FVII:c levels. Lack of relations between severity of clinical manifestations and genotypes was observed; however, a relationship between the nonpathogeneous mutations and clinical phenotypes was noticed. A wide phenotypic inter-individual variability was detected, which suggests the presence of other extra-genetic components influencing the expressivity of the deficiency.

Epidural analgesia in pregnant with deficit of factor VII

The congenital deficit of FVII of coagulation it's an anomaly of genetic transmission autosomal recessive type, it can occur with clinical manifestations like hematomas and spontaneous bleeding or not. The normal levels of FVII it's found between 70%-130% of the laboratory reference value. For unknown reasons there is a poor correlation between levels of FVII and bleeding risk. During pregnancy coagulation can be significantly altered, there is a no clear consensus and a very few information about how to act during labor in a patient with a FVII deficit. The case of a 35-year-old patient with 35 weeks of gestation and congenital deficit of the coagulation FVII (36%) is presented, epidural analgesia is performed during labor previously administering activated recombinant FVII (rFVIIa) without complications (Spinal hematoma, postpartum bleeding, thrombosis).

Novel factor VII gene mutations in six families with hereditary coagulation factor VII deficiency

Introduction

Hereditary human coagulation factor VII (FVII) deficiency is an inherited autosomal recessive hemorrhagic disease involving mutations in the F7 gene. The sites and types of F7 mutations may influence the coagulation activities of plasma FVII (FVII: C) and severity of hemorrhage symptoms. However, the specific mutations that impact FVII activity are not completely known.

Methods

We tested the coagulation functions and plasma activities of FVII in seven patients recruited from six families with hereditary FVII deficiency and sequenced the F7 gene of the patients and their families. Then, we analyzed the genetic information from the six families and predicted the structures of the mutated proteins.

Results

In this study, we detected 11 F7 mutations, including four novel mutations, in which the mutations p.Phe84Ser and p.Gly156Cys encoded the Gla and EGF domains of FVII, respectively, while the mutation p.Ser339Leu encoded the recognition site of the enzymatic protein and maintained the conformation of the catalytic domain structure. Meanwhile, the mutation in the 5′ untranslated region (UTR) was closely associated with the mRNA regulatory sequence.

Conclusion

We have identified novel genetic mutations and performed pedigree analysis that shed light on the pathogenesis of hereditary human coagulation FVII deficiency and may contribute to the development of treatments for this disease.

In this study, we performed coagulation index tests and gene sequencing on 7 hereditary FVII deficiency patients and their family members to explain the pathogenesis of the disease based on the analysis of their genetic information. Also, we compared the structures of newly discovered mutant proteins with the wild type and predicted their pathogenicity. To sum up, this study expands our insight on the pathogenesis of hereditary human coagulation FVII deficiency.

Identification of two novel mutations in three children with congenital factor VII deficiency

Congenital factor VII deficiency (FVIID) is a rare F7 gene mutation causing bleeding disorder inherited in an autosomal recessive manner. In this study, we aimed to identify genetic defects and analyze their relationships with phenotype in three Chinese FVIID patients. The diagnosis of FVIID was made based on FVII coagulant activity (FVII:C) levels assessed through prothrombin time assay. Direct sequencing and protein modeling were performed to detect genetic mutations and the resulting protein expression. Patient 1, a 2-year-old girl, presented with mild bleeding and was found to have a FVII:C of 0.2% and a compound heterozygous F7 Cys389Gly/Cys115Arg mutation. Patient 2, a 7-year-old boy, consulted for moderate bleeding and was found to have a FVII:C of 0.8% and a compound heterozygous F7 Thr241Asn/Pro324Leu mutation. Patient 3, a 5-year-old boy who developed a mild bleeding after trauma was found to have a FVII:C of 1.8% and a compound heterozygous F7 Thr241Asn/ IVS5-2A>G mutation. We hereby report three congenital FVIID patients with FVII:C less than 2% and their respective F7 mutations, two of which (F7 Cys115Arg, Pro324Leu) are novel. The molecular model analysis of the two novel mutations F7 Cys115Arg and Pro324Leu respectively indicated impairment of the proper folding of epidermal growth factor 1 domain situated on F7 gene and impairment of the procoagulant function of FVII both leading to the congenital deficiency of FVII.

Molecular Characterization of Two Homozygous Factor VII Variants Associated with Intracranial Bleeding

Clinical parameters have been extensively studied in factor (F) VII deficiency, but the knowledge of molecular mechanisms of this disease is scarce. We report on three probands with intracranial bleeds at an early age, one of which had concomitant high titer of FVII inhibitor. The aim of the present study was to identify the causative mutations and to elucidate the underlying molecular mechanisms. All nine F7 exons were sequenced in the probands and the closest family members. A homozygous deletion in exon 1, leading to a frame shift and generation of a premature stop codon (p.C10Pfs*16), was found in proband 1. Probands 2 and 3 (siblings) were homozygous for a missense mutation in exon 8, resulting in a glycine (G) to arginine (R) substitution at amino acid 240 (p.G240R). All probands had severely reduced FVII activity (FVII:C < 1 IU/dL). Treatment consisted of recombinant FVIIa and/or plasma concentrate, and proband 1 developed a FVII inhibitor shortly after initiation of treatment. The FVII variants were overexpressed in mammalian cell lines. No FVII protein was produced in cells expressing the p.C10Pfs*16 variant, and the inhibitor development in proband 1 was likely linked to the complete absence of circulating FVII. Structural analysis suggested that the G to R substitution in FVII found in probands 2 and 3 would destabilize the protein structure, and cell studies demonstrated a defective intracellular transport and increased endoplasmic reticulum stress. The molecular mechanism underlying the p.G240R variant could be reduced secretion caused by protein destabilization and misfolding.

Epidural analgesia in pregnant with deficit of factor VII

The congenital deficit of FVII of coagulation it's an anomaly of genetic transmission autosomal recessive type, it can occur with clinical manifestations like hematomas and spontaneous bleeding or not. The normal levels of FVII it's found between 70%-130% of the laboratory reference value. For unknown reasons there is a poor correlation between levels of FVII and bleeding risk. During pregnancy coagulation can be significantly altered, there is a no clear consensus and a very few information about how to act during labor in a patient with a FVII deficit. The case of a 35-year-old patient with 35 weeks of gestation and congenital deficit of the coagulation FVII (36%) is presented, epidural analgesia is performed during labor previously administering activated recombinant FVII (rFVIIa) without complications (Spinal hematoma, postpartum bleeding, thrombosis).

Factor VII Deficiency in Patients Receiving Chronic Packed Cell Transfusions

Acquired factor VII deficiency is a rare coagulopathy that has not been reported in transfusion-dependent patients so far. In this study, we reviewed files of 26 transfusion-dependent patients for coagulation profiles, factor V levels, factor VII levels, possible environmental factors influencing factor VII levels, and bleeding history. In 26 of 29 patients (89.6%), we found mild factor VII deficiency (<60%) with levels ranging between 35% and 56%. Bleeding history was unremarkable. We concluded that transfusion-dependent patients may have mild factor VII deficiency with no bleeding tendency under physiologic conditions.

Maintaining plasma quality and safety in the state of ongoing epidemic - The role of pathogen reduction

In the field of transfusion medicine, many pathogen reduction techniques (PRTs) are currently available, including those based on photochemical (PI) and photodynamic inactivation (PDI). This is particularly important in the face of emerging viral pathogens that may pose a threat to blood recipients, as in the case of the COVID-19 pandemic. However, PRTs have some limitations, primarily related to their adverse effects on coagulation factors, which should be considered before their intended use. A comprehensive search of PubMed, Wiley Online Library and Science Direct databases was conducted to identify original papers. As a result, ten studies evaluating fresh plasma and frozen-thawed plasma treated with different PI/ PDI methods and evaluating concentrations of coagulation factors and natural anticoagulants both before and after photochemical treatment were included in the review. The use of PI and PDI is associated with a significant decrease in the activity of all analysed coagulation factors, while the recovery of natural anticoagulants remains at a satisfactory level, variable for individual inactivation methods. In addition, the published evidence reviewed above does not unequivocally favour the implementation of PI/PDI either before freezing or after thawing as plasma products obtained with these two approaches seem to satisfy the existing quality criteria. Based on current evidence, if implemented responsibly and in accordance with the current guidelines, both PI and PDI can ensure satisfactory plasma quality and improve its safety.

Generation of a human induced pluripotent stem cell line, YCMi002-A, from a Factor VII deficiency patient carrying F7 mutations

Factor VII (FVII) deficiency is the most common among the rare bleeding disorders, which is caused by mutations in coagulation factor VII. Clinical features caused by FVII deficiency vary from mild or asymptomatic to fatal cerebral hemorrhage. We generated an induced pluripotent stem cell (iPSC) line, YCMi002-A, from FVII deficiency patient-derived fibroblasts. YCMi002-A cells are characterized by novel compound heterozygous mutations. The c.345C > A; p.C115X is well known and the second one, c.1276C > T; p.Q426X, remains novel. YCMi002-A cells may help researchers to understand correlation between these mutations and the symptoms of FVII deficiency.

Pharmacokinetics and pharmacodynamics of a recombinant fusion protein linking activated coagulation factor VII with human albumin (rVIIa-FP) in patients with congenital FVII deficiency

Objectives: Recombinant fusion protein linking activated factor VIIa to human albumin (rVIIa-FP) is a therapeutic option designed to prevent and treat bleeding events in patients with congenital FVII deficiency with reduced infusion frequency compared to current FVII treatments. This study characterized the pharmacokinetics (PK) and pharmacodynamics (PD) of rVIIa-FP.Methods: A phase I multicenter, randomized, open-label, parallel-arm, single-dose study (NCT02470871) was conducted in nine patients with severe congenital FVII deficiency. Patients received their routine FVII product (30 IU/kg plasma-derived FVII [pdFVII] or 25 μg/kg recombinant activated FVII (rFVIIa) [eptacog alfa]), and were then randomly assigned to receive 100 or 300 μg/kg of rVIIa-FP. Blood samples for PK and PD assessments were drawn up to 48 hr after administration. FVIIa activity was determined using a one-stage clotting assay. PD parameters were derived from thrombin generation testing, using the Nijmegen hemostasis assay.Results: rVIIa-FP showed improved PK compared to rFVIIa, with 2- to 3-fold longer t_1/2 and 4- to 8-fold lower clearance. Analysis of PD data showed a sustained suppression of lag time below 4.5 min (upper limit of healthy people) for rVIIa-FP compared to rFVIIa. AUEC and EC_max were similar across the two dose groups of rVIIa-FP and rFVIIa.Discussion: rVIIa-FP was well tolerated in patients with congenital FVII deficiency, showed a longer half-life and lower clearance compared to rFVIIa, and lag time remaining within healthy ranges for ≥8 hr.Conclusion: These results warrant further investigation into the efficacy of rVIIa-FP to control and prevent bleeding in patients with FVII deficiency.

Management of pregnancy in women with factor VII deficiency: A case series

INTRODUCTION

Inherited factor VII deficiency is the most common autosomal recessive inherited bleeding disorder, with an estimated incidence of one per 500 000 cases in the general population. Bleeding manifestations correlate poorly with circulating FVII levels. During pregnancy, increases in FVII levels can occur in women with mild-moderate FVII deficiencies but not in those with severe deficiency.

AIM

We present five pregnant patients with FVII deficiency and describe the management during their pregnancies and peripartum periods.

METHODS

Retrospective analysis of six pregnancies in five women with FVII deficiency followed during pregnancy and delivery at an academic medical centre between January 2013 and December 2019.

RESULTS

Of the five patients, two had severe, one with moderate and two with mild FVII deficiency. Early postpartum haemorrhage (PPH) occurred in two patients. One of the two severe FVII-deficient patients had PPH with a laceration at delivery despite replacement therapy with recombinant factor VII. The other PPH occurred in a patient with mild FVII deficiency who delivered twins by caesarean section under general anaesthesia. Neuraxial anaesthesia was utilized in only one woman with mild deficiency whose FVII level normalized at the end of the pregnancy.

CONCLUSIONS

Management of delivery for women with FVII deficiency should be addressed on a case-by-case basis at centres with expertise in rare bleeding disorders, maternal foetal medicine and obstetric anaesthesiology. These management discussions should factor the patient's bleeding history, third trimester PT, FVII level, multiple gestation and mode of delivery.

Clinical problems and surgical interventions in inherited factor VII deficiency

Aim:

Factor VII deficiency is one of the hereditary coagulation disorders that has autosomal reccessive inheritance and is observed relatively frequently (1/500 000). It is clinically heterogeneous, and may be asymptomatic or lead to life-threatening bleeding. Thus, there is no correlation between FVII activity and clinical findings. Plasma-derived and recombinant FVII concentrates are currently used for treatment. In countries where access to these products is lacking, fresh frozen plasma and prothrombin complex concentrates are also used, though they contain low amounts of factor FVII. In this study, we present the clinical properties, treatments, and surgical interventions used in patients followed up in our clinic with a diagnosis of factor FVII deficiency.

Material and Methods:

Patients who were diagnosed as FVII deficiency in Division of Pediatric Hematology and Oncology between July 1997 and July 2018, were included in the study. The patients’ demographic characteristics, symptoms at presentation, PT, aPTT, and FVII values, types of bleeding, and treatments and surgical interventions used, were recorded. The bleedings observed in the patients were classified by severity as asymptomatic, minor, and major.

Results:

A total of 18 patients (7 girls and 11 boys) with a mean age of 9.64±9.63 years were included in the study. The mean follow-up time was found as 78.06±54.4 months. When the bleedings were classified clinically, no bleeding was observed in eight patients (44.4%). The factor FVII level was found as <10% in three of these eight asymptomatic patients and above 20% in the others. Minor bleeding was observed in nine patients (50%) and major bleeding was observed in one patient. When the patients were classified as asymptomatic and symptomatic, there was no significant difference between the two groups in terms of FVII level (p=0.57). A total of 21 surgical interventions were performed in 14 (78%) of 18 patients who were being followed up.

Conclusion:

FVII deficiency has a very wide spectrum both clinically and in terms of approach to surgical interventions. Therefore, patients with factor FVII deficiency should be followed up and treated by comprehensive care centers with close collaboration of multiple disciplines.

Peculiar Congenital Factor VII Defect with the Proposita and Her Mother Showing the Same Compound Heterozygosity for Thr384Met and Arg413Gln

OBJECTIVE

To investigate a family with factor VII (FVII) deficiency from Argentina.

PATIENTS AND METHODS

The proposita is a 14-year-old girl who presented with a mild to moderate bleeding tendency. Menorrhagia is controlled with periodical administration of small doses of recombinant FVII concentrate. The mother of the proposita has a similar bleeding tendency.

RESULTS

FVII activity in both patients was 20% of normal; FVII antigen was 35% of normal. Molecular biology investigation revealed that the proposita was compound heterozygote between Thr384Met and Arg413Gln. The mother had the same mutations. This was due to the fact that the father of the proposita and her maternal grandfather both carried, in spite of no relation, the same mutation, namely Arg413Gln.

CONCLUSIONS

The identical defect which presented in the propositaand her mother could be explained by the genetic analysis of the father and maternal grandfather of the proposita who happened to have the same mutation (Arg413Gln).

Hepatic Differentiation of Marmoset Embryonic Stem Cells and Functional Characterization of ESC-Derived Hepatocyte-Like Cells

Background

Primary human hepatocytes (PHHs) are the ideal candidates for studying critical liver functions such as drug metabolism and toxicity. However, as they are isolated from discarded livers that are unsuitable for transplantation, they possess limited expansion ability in vitro and their enzymatic functions deteriorate rapidly because they are often of poor quality. Therefore, there is a compelling reason to find reliable alternative sources of hepatocytes.

Methods

In this study, we report on efficient and robust differentiation of embryonic stem cells (ESC) from the common marmoset Callithrix jacchus into functional hepatocyte-like cells (HLC) using a simple, and reproducible three-step procedure. ESC-derived HLCs were examined by morphological analysis and tested for their expression of hepatocyte-specific markers using a combination of immunohistochemistry, RT-PCR, and biochemical assays. Primary human hepatocytes were used as controls.

Results

ESC-derived HLCs expressed each of the hepatocyte-specific markers tested, including albumin; α-fetoprotein; asialoglycoprotein receptor 1; α-1 antitrypsin; hepatocyte nuclear factors 1α and 4; cytokeratin 18; hepatocyte growth factor receptor; transferrin; tyrosine aminotransferase; alkaline phosphatase; c-reactive protein; cytochrome P450 enzymes CYP1A2, CYP2E1 and CYP3A4; and coagulation factors FVII and FIX. They were functionally competent as demonstrated by biochemical assays in addition to producing urea.

Conclusion

Our data strongly suggest that marmoset HLCs possess characteristics similar to those of PHHs. They could, therefore, be invaluable for studies on drug metabolism and cell transplantation therapy for a variety of liver disorders. Because of the similarities in the anatomical and physiological features of the common marmoset to that of humans, Callithrix jacchus is an appropriate animal model to study human disease conditions and cellular functions.

The effect of the chemical chaperone 4-phenylbutyrate on secretion and activity of the p.Q160R missense variant of coagulation factor FVII

Background

Congenital coagulation factor (F) VII deficiency is a rare bleeding disorder caused by mutations in the F7 gene. The missense factor FVII variant p.Q160R is the disease-causing mutation in all Norwegian FVII deficient patients and results in reduced biological activity and antigen levels of FVII in patient plasma. Previous in vitro studies on this variant demonstrated impaired intracellular trafficking and reduced secretion, possibly due to protein misfolding. The aim of the study was therefore to assess the impact of chemical chaperones on cellular processing and secretion of this variant using a cell model based on overexpression of the recombinant protein.

Results

Through screening of compounds, we identified 4-phenylbutyrate (4-PBA) to increase the secretion of recombinant (r) FVII-160R by ~ 2.5-fold. Additionally, treatment with 4-PBA resulted in a modest increase in specific biological activity. Intracellular localization studies revealed that upon treatment with 4-PBA, rFVII-160R was secreted through Golgi and Golgi reassembly-stacking protein (GRASP)-structures.

Conclusions

The present study demonstrates that the chemical chaperone 4-PBA, restores intracellular trafficking and increases the secretion of a missense FVII variant with functional properties in the extrinsic coagulation pathway.

Coagulant activity of recombinant human factor VII produced by lentiviral human F7 gene transfer in immortalized hepatocyte-like cell line

Human mesenchymal stem cells (hMSCs) have the potential to differentiate into hepatocyte-like cells, indicating that these cells may be the new target cell of interest to produce biopharmaceuticals. Our group recently established a hMSC-derived immortalized hepatocyte-like cell line (imHC) that demonstrates several liver-specific phenotypes. However, the ability of imHC to produce coagulation factors has not been characterized. Here, we examined the potential for imHC as a source of coagulation protein production by investigating the ability of imHC to produce human factor VII (FVII) using a lentiviral transduction system. Our results showed that imHC secreted a low amount of FVII (~22 ng/mL) into culture supernatant. Moreover, FVII from the transduced imHC (0.11 ± 0.005 IU/mL) demonstrated a similar coagulant activity compared with FVII from transduced HEK293T cells (0.12 ± 0.004 IU/mL) as determined by chromogenic assay. We demonstrate for the first time, to the best of our knowledge, that imHC produced FVII, albeit at a low level, indicating the unique characteristic of hepatocytes. Our study suggests the possibility of using imHC for the production of coagulation proteins.

N-Glycan-calnexin interactions in human factor VII secretion and deficiency

Factor VII (FVII) is a key serine protease in blood coagulation. N-glycosylation in FVII has been shown to be critical for protein secretion. To date, however, the underlying biochemical mechanism remains unclear. Recently, we found that N-glycans in the transmembrane serine protease corin are critical for calnexin-assisted protein folding and extracellular expression. In this study, we tested the hypothesis that N-glycans in the FVII protease domain mediate calnexin-assisted protein folding and that naturally occurring F7 mutations abolishing N-glycosylation impair FVII secretion. We expressed human FVII wild-type (WT) and mutant proteins lacking one or both N-glycosylation sites in HEK293 and HepG2 cells in the presence or absence of a glucosidase inhibitor. FVII expression, secretion and binding to endoplasmic reticulum chaperones were examined by immune staining, co-immunoprecipitation, Western blotting, and ELISA. We found that N-glycosylation at N360 in the protease domain, but not N183 in the pro-peptide domain, of human FVII is required for protein secretion. Elimination of N-glycosylation at N360 impaired calnexin-assisted FVII folding and secretion. Similar results were observed in WT FVII when N-glycan-calnexin interaction was blocked by glucosidase inhibition. Naturally occurring F7 mutations abolishing N-glycosylation at N360 reduced FVII secretion in HEK293 and HepG2 cells. These results indicate that N-glycans in the FVII protease domain mediate calnexin-assisted protein folding and subsequent extracellular expression. Naturally occurring F7 mutations abolishing N-glycosylation in FVII may impair this mechanism, thereby reducing FVII levels in patients.

Acquired Factor VII deficiency - a rare but important consideration

INTRODUCTION

Isolated acquired Factor VII deficiency is a rare coagulation disorder which is independent of vitamin K deficiency. The exact pathophysiological basis of this condition is unclear. We present a series of cases highlighting different clinical scenarios where this condition was encountered.

CASE SERIES

The first case presented with intra-abdominal sepsis. The second was a patient admitted with acute kidney injury and subsequently diagnosed with myeloma. The final case presented with microangiopathic haemolytic anaemia and was suspected of having atypical Haemolytic Uraemic Syndrome. In each case, there was no family or personal history of a bleeding disorder. Follow-up Factor VII levels after recovery from illness was normal in all three cases.

CONCLUSION

Acquired Factor VII deficiency is an uncommon but important finding which should be considered in the general medical setting when an isolated prolonged prothrombin time is detected.

Thrombotic Events in Homozygotes with a Proven or Highly Probable Arg304Gln Factor VII Mutation (FVII Padua)1): Only Limited Replacement Therapy is Needed in Case of Surgery

OBJECTIVE

To investigate the prevalence of thrombotic events among patients with proven or highly probable homozygosis for the Arg304Gln (Factor VII Padua) defect or compound heterozygosis containing the Arg304Gln mutation.

METHODS

Homozygotes and compound heterozygotes proven by molecular studies to have the Arg304Gln mutation were gathered from personal files and from two PubMed searches. In addition, patients with probable homozygosis on the basis of clotting tests (discrepancies among Factor VII activity levels according to the tissue thromboplastin used) were also gathered.

RESULTS

30 proven homozygotes and 17 probable ones were gathered together with 8 compound heterozygotes. In the latter use, the associated mutation was Cys135Arg (twice), Gly180Arg, Arg304Trp, Arg315Trp, His348Gln, Gly365Cys. The prevalence of venous thrombotic events was 16.6, 11.8 and 11.1 percent, respectively for the three groups of patients. Heterozygotes showed no thrombotic event. The difference for proven homozygotes was statistically significant, while for the other groups only a trend was present.

CONCLUSION

proven homozygous or compound heterozygous patients with the Arg304Gln mutation showed a higher than expected incidence of thrombotic events. The same is true for probable cases gathered only on the basis of clotting tests. These patients, because of their frequent lack of bleeding and for their relatively high prevalence of thrombosis should probably receive only limited replacement therapy in case of surgical procedures.

Benefits and Pitfalls of Point-of-Care Coagulation Testing for Anticoagulation Management: An ACLPS Critical Review

Objectives

Point-of-care (POC) testing is generally less precise and has higher reagent costs per test than laboratory-based assays. However, POC hemostasis testing can offer significant advantages in particular situations: patient-managed warfarin therapy as well as rapid turnaround time heparin management for intraoperative patients. Of note, POC hemostasis testing is generally approved for the purposes of anticoagulation monitoring and is inferior to laboratory coagulation testing for the diagnosis of congenital or acquired coagulopathy.

Methods

The frequently used POC coagulation instruments for POC international normalized ratio and activated clotting time are reviewed, as well as their typical performance relative to central laboratory testing (where available).

Results

Several cases are discussed that highlight the benefits, as well as pitfalls, of POC coagulation testing.

Conclusions

POC coagulation testing for anticoagulation monitoring offers advantages in particular situations. Clear policies and protocols must be developed to guide proper use of POC versus central laboratory hemostasis testing.

Factor X Deficiency Due to a Compound Heterozygosis Between a New Mutation (Gla72Asp) in Exon 2 and an Already Known one (Gly154Arg) in Exon 5: Factor X Mar Del Plata1)

BACKGROUND

Investigation of rare bleeding disorders in Latin-America.

OBJECTIVES

The report of a new case of FX deficiency due to a compound heterozygosis.

METHODS

Accepted clotting procedures were used. Sequencing of DNA was carried out by means of Applied Biosystems Instruments.

RESULTS

A compound heterozygote due to the association of a new mutation (Gla72Asp) with an already known mutation (Gly154Arg) of the FX gene is reported. The proposita is a 38 year old female who had a moderate bleeding tendency (menorrhagia, epistaxis, easy bruising). The proposita has never received substitution therapy but in the occasion of a uterine biopsy. The mother was asymptomatic but was a heterozygote for the new mutation. The father was asymptomatic but had deserted the family and could not be investigated. After this abandonment the mother of the proposita re-married with an asymptomatic man and she gave birth to a son who was asymptomatic but was also heterozygous for the new mutation (Gla72Asp). As a consequence it has to be assumed that the first husband of the mother of the proposita was heterozygous for the known mutation (Gly154Arg).

CONCLUSIONS

This is the third case of a new mutation in the FX gene reported, during the past few years, in Argentina.

Vitamin K-Dependent Coagulation Factors That May be Responsible for Both Bleeding and Thrombosis (FII, FVII, and FIX)

Vitamin K-dependent clotting factors are commonly divided into prohemorrhagic (FII, FVII, FIX, and FX) and antithrombotic (protein C and protein S). Furthermore, another protein (protein Z) does not seem strictly correlated with blood clotting. As a consequence of this assumption, vitamin K-dependent defects were considered as hemorrhagic or thrombotic disorders. Recent clinical observations, and especially, recent advances in molecular biology investigations, have demonstrated that this was incorrect. In 2009, it was demonstrated that the mutation Arg338Leu in exon 8 of FIX was associated with the appearance of a thrombophilic state and venous thrombosis. The defect was characterized by a 10-fold increased activity in FIX activity, while FIX antigen was only slightly increased (FIX Padua). On the other hand, it was noted on clinical grounds that the thrombosis, mainly venous, was present in about 2% to 3% of patients with FVII deficiency. It was subsequently demonstrated that 2 mutations in FVII, namely, Arg304Gln and Ala294Val, were particularly affected. Both these mutations are type 2 defects, namely, they show low activity but normal or near-normal FVII antigen. More recently, in 2011-2012, it was noted that prothrombin defects due to mutations of Arg596 to Leu, Gln, or Trp in exon 15 cause the appearance of a dysprothrombinemia that shows no bleeding tendency but instead a prothrombotic state with venous thrombosis. On the contrary, no abnormality of protein C or protein S has been shown to be associated with bleeding rather than with thrombosis. These studies have considerably widened the spectrum and significance of blood coagulation studies.

A new perspective on perioperative coagulation management in a patient with congenital factor VII deficiency: A case report

RATIONALE

Congenital factor VII (FVII) deficiency is a rare coagulopathy. There are little clinical data for congenital FVII deficiency and no evidence-based medicine guidelines for treatment.

PATIENT CONCERNS

A 48-year-old woman with gallbladder stones suffered from intermittent abdominal pain for 2 months that was accompanied by an abnormally prolonged prothrombin time.

DIAGNOSES

The woman was diagnosed as having cholecystolithiasis with cholecystitis and congenital FVII deficiency.

INTERVENTION

Preoperative evaluation confirmed the necessity of recombinant activated factor VII (rFVIIa) replacement therapy. We monitored the plasma factor VII activity (FVII:C) and coagulation function, determined the half-life of rFVIIa in the patient, and administered personalized rFVIIa replacement therapy.

OUTCOMES

Laparoscopic cholecystectomy was performed successfully, and the patient recovered well without any complications.

LESSONS

The clinical manifestations and severity of bleeding in patients with congenital FVII deficiency can vary widely. The history of massive bleeding and plasma FVII:C are the decisive factors when implementing a replacement therapy. The actual half-life of rFVIIa can be determined from intensive monitoring results of plasma FVII:C at the beginning of replacement therapy, which could further guide the personalization of rFVIIa replacement therapy.

Homozygous congenital factor VII deficiency with a novel mutation, associated with severe spontaneous intracranial bleeding in a neonate

OBJECTIVE

Herein, a neonate with congenital FVII deficiency is presented.

BASIC METHOD

Diagnosis of congenital FVII deficiency was confirmed by genetic analysis using next-generation sequencing method (MiSeq-Illumina).

RESULT

Our patient was found to have a novel homozygous mutation.

CONCLUSION

Early diagnosis and treatment of congenital FVII deficiency can be crucial.

Acquired factor VII deficiency causing severe bleeding disorder secondary to AL amyloidosis of the liver

A 52 year-old male presented with neck pain after undergoing thyroidectomy for a goiter three weeks prior which was complicated by a neck hematoma requiring evacuation. Computed tomography (CT) scan showed a neck hematoma requiring evacuation and he received desmopressin with cessation of bleeding. Coagulation studies were normal. He returned eighteen months later with severe oral mucosal bleeding after a dental procedure and required transfusions with red blood cells, platelets, and fresh frozen plasma (FFP) in addition to desmopressin, Humate-P, aminocaproic acid, and surgical packing. A comprehensive bleeding diathesis workup was normal. He was readmitted six months later due to abdominal pain and distention and found to have massive hepatosplenomegaly on CT. A new coagulopathy workup revealed prolonged INR to 1.5, corrected prothrombin time mixing study, and a low factor VII level (29%), suggesting acquired factor VII deficiency. A transjugular liver biopsy revealed extensive involvement by ALamyloidosis- Kappa type. He then developed a large right retroperitoneal hematoma which required multiple transfusions with FFP, cryoprecipitate, aminocaproic acid, and vitamin K with slight success. Hemorrhage was subsequently stabilized with recombinant factor VIIa administered every four hours which corresponded with correction of factor VII levels and PT and eventual cessation hemorrhage. Acquired factor VII deficiency causing severe coagulopathy was attributed to hepatic amyloidosis ALkappa subtype. We started treatment with bortezomib, dexamethasone, and cyclophosphamide, however, the patient succumbed to uncontrolled hemorrhage. Acquired factor VII deficiency is extremely rare and to our knowledge, this is the only known case of factor VII deficiency secondary to amyloidosis involving the liver.

Factor VII deficiency - an enigma; clinicohematological profile in 12 cases

OBJECTIVE

Factor VII deficiency is the commonest of the rare bleeding disorders with limited knowledge on clinical profile. The objective of this study was to study the prevalence and clinico-hematological profile of factor VII-deficient patients.

METHODS

It is a retrospective observational study of probable inherited factor VII deficiency covering 18 months. Their clinical profile, family history, investigation and treatment records were studied in detail.

RESULTS

The study group comprised of total 12 factor VII deficiency cases with mean age of 17.5 years of onset of symptoms. The commonest symptom was menorrhagia (41.6%) followed by epistaxis (25%) and easy bruisability (16.6%). These 12 patients when categorized according to bleeding severity: severe bleeding - 2, moderate bleeding - 3, mild bleeding - 6 and asymptomatic - 1. All cases had prolonged prothrombin time (PT) with mean PT of 35.4 seconds (range 18-50 seconds) and mean prolongation of PT from upper limit of normal - 19.4 seconds (range 2-34 seconds). Factor VII levels ranged from < 1-40% in these patients. Clinical symptoms were not in concordance with factor levels. Of 12 patients, required treatment other than local measures.

DISCUSSION AND CONCLUSION

Inherited factor VII deficiency is the commonest autosomally inherited factor deficiency with marked variation in the age of presentation and clinical symptoms. The laboratory results in form of PT and factor VII levels do not correlate with the severity of clinical presentation. A comprehensive evaluation to exclude acquired causes of factor VII deficiency, e.g. obesity, liver diseases, vitamin K deficiency and acquired inhibitors is required before labeling it as inherited in the absence of family history and molecular studies.

Delayed Presentation of Compartment Syndrome of the Thigh in a Previously Undiagnosed Factor VII-Deficient High School Football Athlete: A Case Report

CASE

We describe a case of delayed presentation of compartment syndrome in the anterior aspect of the thigh in a high school athlete. The patient had sustained a blow to the thigh 8 days prior to presentation, and had continued to practice football in the setting of undiagnosed coagulopathy. He presented with severe thigh pain and the inability to contract the thigh muscles.

CONCLUSION

A high index of suspicion for compartment syndrome is indicated for patients with disproportionate pain, especially in the setting of relatively minor trauma. Underlying coagulopathy should be investigated in patients with compartment syndrome because there is a high incidence of bleeding disorders in this population.

A novel factor X mutation Cys81 by Arg and a reported factor VII polymorphism Arg353 replaced by Gln co-occured in a patient

: Coagulation factor X and factor VII (FVII) are both very important components in blood coagulation. To study the molecular pathogenic mechanism of the inherited factor X and FVII deficiency, the factor X activity (FX:C) and FVII activity were tested with one-stage clotting methods. The factor X antigen and factor FVII antigen were tested with ELISA. All the exons, intron-exon boundaries and 5',3'-flanking regions of F10 and F7 genes were amplified by PCR with direct sequencing. The ClustalX software was used to analyze the conservative property of the mutation sites. The PolyPhen-2 and Sorting Intolerant From Tolerant (SIFT) online bioinformatics softwares were taken to predict whether the point mutation could affect protein function. The software Swiss-pdb Viewer was brought to analyze the impact of mutations on the structure and function of the protein. The thrombin generation tests were applied to evaluate whether there were obstacles in producing thrombin about the mutant protein. The FX:C and FVII activity of the proband were reduced to 35 and 42%, and the factor X antigen and factor FVII antigen were decreased to 43 and 55%, simultaneously. Correspondingly, a FX:Cys81Arg (Cys81 by Arg) mutation and a FVII:Arg353 replaced by Gln polymorphism were detected in the proband. The Cys81 of factor X was conserved among homologous species, but the Arg353 of FVII was not. All softwares analysis results indicated protein features and structures might be affected by the mutation and the polymorphism. And the thrombin generation tests showed that the mutant protein had obstacles in thrombin generation. We identified a FX:Cys81Arg mutation and a FVII:Arg353 replaced by Gln polymorphism in the proband. And they accounted for the decrease of the activity and antigen of factor X and FVII. Of note, the Cys81Arg of factor X was first reported in the world.

Bleeding symptoms at disease presentation and prediction of ensuing bleeding in inherited FVII deficiency

Individuals with inherited factor VII (FVII) deficiency display bleeding phenotypes ranging from mild to severe, with 30% of patients having always been asymptomatic (non-bleeding). In 626 FVII-deficient individuals, by analysing data from the International Factor VII (IF7) Registry and the Seven Treatment Evaluation Registry (STER), we determined whether bleeding type at disease presentation and FVII coagulant activity (FVIIc) predict ensuing bleeds. At disease presentation/diagnosis, 272 (43.5%) individuals were non-bleeding, 277 (44.2%) had minor bleeds, and 77 (12.3%) had major bleeds. During a median nine-year index period (IP) observation, 87.9% of non-bleeding individuals at presentation remained asymptomatic, 75.1% of minor-bleeders had new minor bleeds, and 83.1% of major-bleeders experienced new major bleeds. After adjusting for FVIIc levels and other clinical and demographic variables, the relative risk (RR) for ensuing bleedings during the IP was 6.02 (p <0.001) and 5.87 (p <0.001) in individuals presenting with major and minor bleeds, respectively. Conversely, compared to non-bleeding individuals, a 10.95 (p = 0.001) and 28.21 (p <0.001) RR for major bleedings during the IP was found in those with minor and with major bleeds at presentation, respectively. In conclusion, in FVII deficiency, the first major bleeding symptom is an independent predictor of the risk of subsequent major bleeds.

Role of clinical and laboratory parameters for treatment choice in patients with inherited FVII deficiency undergoing surgical procedures: evidence from the STER registry

Perioperative bleeding is a major concern in patients with factor VII (FVII) deficiency. Evaluating data of 95 FVII-deficient patients undergoing 110 surgical procedures (61 major, 49 minor), we assessed the impact of type of surgery, bleeding phenotype and FVII coagulant activity (FVII:C) levels on perioperative replacement therapy (RT). Compared to those with higher FVII:C levels, patients with <3% FVII:C received a higher number of RT doses (8 vs. 2, P = 0·003) for a longer RT duration (3 days vs. 1 day, P = 0·001), with no difference in RT dose. Similarly, patients with a history of major bleeds received a higher number of RT doses (8·5 vs. 2-3, P = 0·013) for a longer RT duration (2 days vs. 1 day, P = 0·005) as compared to those with a history of minor bleeds or to asymptomatic patients. No difference in RT was found among major and minor surgical procedures. Overall, multivariate analysis showed that history of major bleeding was the only independent predictor of number of RT doses (β = 0·352, P = 0·001) and RT duration (β = 0·405, P = 0·018). Overall, a ≈20 μg/kg perioperative RT was efficacious in 95·5% of cases. The infusion should be repeated ≈8 times in high-risk subsets (i.e. patients with a history of major bleeding).

Factor VII deficiency: a novel missense variant and genotype-phenotype correlation in patients from Southern Italy

This study aimed at attempting to correlate genotype and phenotype in factor VII deficiency. Here, we present molecular and clinical findings of 10 patients with factor VII deficiency. From 2013 to 2016, 10 subjects were referred to our center because of a prolonged prothrombin time identified during routine or presurgery examinations or after a laboratory assessment of a bleeding episode. Mutation characterization was performed using the bioinformatics applications PROMO, SIFT, and Polyphen-2. Structural changes in the factor VII protein were analyzed using the SPDB viewer tool. Of the 10 variants we identified, 1 was responsible for a novel missense change (c.1199G>C, p.Cys400Ser); in 2 cases we identified the c.-54G>A and c.509G>A (p.Arg170His) polymorphic variants in the 5′-upstream region of the factor VII gene and exon 6, respectively. To our knowledge, neither of these polymorphic variants has been described previously in factor VII-deficient patients. In silico predictions showed differences in binding sites for transcription factors caused by the c.-54G>A variant and a probable damaging effect of the p.Cys400Ser missense change on factor VII active conformation, leading to breaking of the Cys400-Cys428 disulfide bridge. Our findings further suggest that, independently of factor VII levels and of variants potentially affecting factor VII levels, environmental factors, e.g., trauma, could heavily influence the clinical phenotype of factor VII-deficient patients.

F7 gene variants modulate protein levels in a large cohort of patients with factor VII deficiency. Results from a genotype-phenotype study

Congenital factor VII (FVII) deficiency is a rare bleeding disorder caused by mutations in F7 gene with autosomal recessive inheritance. A clinical heterogeneity with poor correlation with FVII:C levels has been described. It was the objective of this study to identify genetic defects and to evaluate their relationships with phenotype in a large cohort of patients with FVII:C<50 %. One hundred twenty-three probands were genotyped for F7 mutations and three polymorphic variants and classified according to recently published clinical scores. Forty out of 123 patients (33 %) were symptomatic (43 bleedings). A severe bleeding tendency was observed only in patients with FVII:C<0.10 %. Epistaxis (11 %) and menorrhagia (32 % of females in fertile age) were the most frequent bleedings. Molecular analysis detected 48 mutations, 20 not reported in the F7 international databases. Most mutations (62 %) were missense, large deletions were 6.2 %. Compound heterozygotes/homozygotes for mutations presented lower FVII:C levels compared to the other classes (Chi2=43.709, p<0,001). The polymorphisms distribution was significantly different among the three F7 genotypic groups (Chi2=72.289, p<0,001). The presence of truncating mutations was associated with lowest FVII:C levels (Chi2=21.351, p=0.002). This study confirms the clinical and molecular variability of the disease and the type of symptoms. It shows a good correlation between the type of F7 mutation and/or polymorphisms and FVII:C levels, without a direct link between FVII:C and bleeding tendency. The results suggest that large deletions are underestimated and that they represent a common mechanism of F7 gene inactivation which should always be investigated in the diagnostic testing for FVII deficiency.

Factor VII Deficiency: Clinical Phenotype, Genotype and Therapy

Factor VII deficiency is the most common among rare inherited autosomal recessive bleeding disorders, and is a chameleon disease due to the lack of a direct correlation between plasma levels of coagulation Factor VII and bleeding manifestations. Clinical phenotypes range from asymptomatic condition—even in homozygous subjects—to severe life-threatening bleedings (central nervous system, gastrointestinal bleeding). Prediction of bleeding risk is thus based on multiple parameters that challenge disease management. Spontaneous or surgical bleedings require accurate treatment schedules, and patients at high risk of severe hemorrhages may need prophylaxis from childhood onwards. The aim of the current review is to depict an updated summary of clinical phenotype, laboratory diagnosis, and treatment of inherited Factor VII deficiency.