Factor V deficiency: a concise review

F5 6665A>G Polymorphism Is Associated with Increased Risk of Venous Thromboembolism in Females

The main goal of our study was to assess the potential effect of the polymorphism of the coagulation-related genes F2, F5, and F13A on the risk of venous thromboembolism (VTE) development. The study was conducted at the Clinical Center, Podgorica, Montenegro, and included 103 VTE patients and 106 sex- and age-matched healthy controls. Demographic, clinical, and laboratory data were obtained from the medical records and questionnaires. Genotyping for F2 19911A>G (rs3136516), F5 6665A>G (rs6027), and F13A 102G>T (rs5985) was performed by allele-specific PCR. Controlling for the effect of known risk factors, the presence of at least one variant F5 6665 G allele conferred a significantly higher risk of VTE among females [OR (95%CI): 64.06 (5.38; 763.61)], but not among males. In addition, thromboembolic events were associated with comorbidities [OR (95%CI): 197.10 (19.17; 2026.19)], overweight [OR (95%CI): 33.59 (2.47; 456.65)], and the presence of F2 20210G>A [OR (95%CI): 32.43 (4.21; 249.77)] and F5 1601G>A [OR (95%CI): 144.80 (13.59; 1542.63)] in females, as well as with comorbidities [OR (95%CI): 6.32 (1.90; 20.98)], family history of VTE [OR (95%CI): 8.10 (2.28; 28.83)], and the presence of F5 1601G>A [OR (95%CI): 20.10 (2.34; 173.02)] in males. Our study reports an association between the presence of at least one F5 6665G variant allele and an increased risk of VTE development in females. Our results indicate that F5 6665A>G, in combination with other confirmed factors of influence, such as comorbidities, overweight, F2 20210G>A, and F5 1601G>A, could contribute to VTE risk prediction in females.

Clinical, Laboratory, Molecular, and Reproductive Aspects of Combined Deficiency of Factors V and VIII

Congenital combined deficiency of factor V (FV) and factor VIII (FVIII; F5F8D, OMIM 227300) is a rare hereditary coagulopathy and accounts for approximately 3% of cases of rare coagulation disorders. The prevalence of this disease in the general population is estimated to be 1:1,000,000 and is significantly higher in regions where consanguineous marriages are permitted, such as the Mideast and South Asia. The disease has an autosomal recessive mode of inheritance and therefore occurs with an equal incidence among males and females. Heterozygous mutation carriers usually do not have clinical manifestations. The molecular basis of this disease differs from that of stand-alone congenital deficiencies of FVIII and FV. F5F8D is caused by mutations in either LMAN1 or MCFD2, which encode components of a cargo receptor complex for endoplasmic reticulum to Golgi transport of FV and FVIII, leading to defects in an intracellular transport pathway shared by these two coagulation factors. Congenital combined deficiency of FV and FVIII is characterized by decreased activities of both FV and FVIII in plasma, usually to 5 to 30% of normal. Clinical manifestations in most cases are represented by mild or moderate hemorrhagic syndrome. The simultaneous decreases of two coagulation factors present complications in the diagnosis and management of the disease. In female patients, the disease requires a special approach for family planning, pregnancy management, and parturition. This review summarizes recent progress in clinical, laboratory, and molecular understanding of this disorder.

Glioblastoma Cells Express and Secrete Alternatively Spliced Transcripts of Coagulation Factor X

Background: Patients with cancer often develop a prothrombotic state that can evolve into venous and arterial thrombosis, which is associated with poor clinical outcomes. Glioblastoma multiforme (GBM) is the most frequently associated with thrombosis, but the underlying causes of this prothrombotic state are poorly defined. Objectives: We designed a study to characterize the expression of coagulation factor X (FX) and its alternatively spliced transcripts in glioblastoma tissues surgically removed from patients and in clonal cell lines. Methods: The F10 mRNA and FX protein were quantified in tissues surgically removed from seven patients with glioblastoma (glioma grade 3-4) and those from non-tumor patients. Glioblastoma cells from three human clonal lines were examined for the expression and secretion of FX at baseline and after the cells were stimulated with lipopolysaccharide (LPS) or subjected to oxygen/glucose starvation in culture. PCR products were subjected to Sanger sequencing and amplicon sequencing to identify F10 isoforms and their ratios. A chromogenic assay was performed to assess FX activity. Results: Glioblastoma tissue and cell lines expressed high levels of the full-length and an alternatively spliced F10 mRNA. The latter produced a C-terminal truncated FX. The ratio of full-length to truncated F10 transcripts was significantly higher in normal brain tissues than in glioblastoma tissue. In cultured cells from the glioblastoma cell lines, FX was secreted to the conditioned medium and was active in cleaving a chemical substrate. The FX expression and secretion were upregulated in cells stimulated with LPS or subjected to oxygen/glucose starvation. Discussion: Glioblastoma cells synthesize and secrete FX that was active in promoting thrombin generation. These findings provide a new underlying mechanism to explain why glioblastoma patients are prone to developing thrombosis.

Perioperative Recommendations for Corneal Refractive Surgery Patients With Inherited Bleeding Disorders

PURPOSE

To synthesize the current literature regarding patients with inherited bleeding disorders and suggest comprehensive evaluation and preoperative recommendations for these patients before undergoing corneal refractive surgery.

METHODS

The literature search was conducted through PubMed, Embase, and Google Scholar databases for publications through January 4, 2024 for reports of ocular bleeding manifestations in patients with inherited bleeding disorders and reports of patients without a history of bleeding disorders who had intraoperative or postoperative hemorrhagic complications with corneal refractive surgery. Additional cases from the literature and a retrospective chart review at a corneal practice were obtained describing patients with inherited bleeding disorders who underwent corneal refractive surgery.

RESULTS

Four articles were found detailing ocular bleeding manifestations in patients with inherited bleeding disorders who underwent ocular surgery other than corneal refractive surgery. Thirty articles were found detailing intraoperative and postoperative bleeding manifestations in patients without a history of inherited bleeding disorders who underwent corneal refractive surgery. Eight cases (3 patients from the literature search and 5 patients from a retrospective chart review) were found regarding patients with inherited bleeding disorders who underwent corneal refractive surgery.

CONCLUSIONS

For corneal refractive surgery with topical anesthesia, the perioperative risk and need for any hemostasis intervention in individuals with an inherited bleeding disorder depends on the type of disorder, status of preoperative factor level concentrations, or a prior history of bleeding. If required, clotting factor optimization should be tailored to each candidate on a case-by-case basis.

Genome-Wide Search for Nonadditive Allele Effects Identifies PSKH2 as Involved in the Variability of Factor V Activity

BACKGROUND

Factor V (FV) is a key molecular player in the coagulation cascade. FV plasma levels have been associated with several human diseases, including thrombosis, bleeding, and diabetic complications. So far, 2 genes have been robustly found through genome-wide association analyses to contribute to the inter-individual variability of plasma FV levels: structural F5 gene and PLXDC2.

METHODS AND RESULTS

The authors used the underestimated Brown-Forsythe methodology implemented in the QuickTest software to search for non-additive genetic effects that could contribute to the inter-individual variability of FV plasma activity. QUICKTEST was applied to 4 independent genome-wide association studies studies (LURIC [Ludwigshafen RIsk and Cardiovascular Health Study], MARTHA [Marseille Thrombosis Association], MEGA [Multiple Environmental and Genetic Assessment], and RETROVE [Riesgo de Enfermedad Tromboembolica Venosa]) totaling 4505 participants of European ancestry with measured FV plasma levels. Results obtained in the 4 cohorts were meta-analyzed using a fixed-effect model. Additional analyses involved exploring haplotype and gene×gene interactions in downstream investigations. A genome-wide significant signal at the PSKH2 locus on chr8q21.3 with lead variant rs75463553 with no evidence for heterogeneity across cohorts was observed (P=0.518). Although rs75463553 did not show an association with mean FV levels (P=0.49), it demonstrated a robust significant (P=3.38x10-9) association with the variance of FV plasma levels. Further analyses confirmed the reported association of PSKH2 with neutrophil biology and revealed that rs75463553 likely interacts with two loci, GRIN2A and POM121L12, known for their involvement in smoking biology.

CONCLUSIONS

This comprehensive approach identifies the role of PSKH2 as a novel molecular player in the genetic regulation of FV, shedding light on the contribution of neutrophils to FV biology.

Characteristics of factor V and protein C based on results from Korean testing centers

OBJECTIVE

The global incidence of thrombosis is increasing. However, research on thrombosis in the context of Korea is scarce. We aimed to analyze the relationship between factor V and protein C test results and thrombosis in Koreans through a domestic commissioned testing institution conducting mass examinations.

METHODS

Results of factor V and protein C tests of 1386 individuals referred simultaneously to EONE Laboratories (Incheon, Republic of Korea) from January 2017 to July 2023 were analyzed retrospectively to identify the association with thrombotic disease. The tests were performed using a STAR MAX (Diagnostica Stago, Asnieres, France) automatic blood coagulation analyzer. The results were analyzed by age and sex.

RESULTS

The inspection rate increased gradually from 2017 to 2022. Women (70.0%) demonstrated a higher test rate than did men (30.0%). Young women reported high test rates; the test rate and age distribution differed by sex. Women aged between 20 and 49 years reported lower factor V and higher protein C concentrations than did men between 20 and 49 years of age.

CONCLUSIONS

The tests were more commonly performed in women than in men. Women aged between 20 and 49 years reported lower factor V concentrations and higher protein C concentrations than men between 20 and 49 years of age. This study will facilitate recognizing and preventing thrombotic diseases in women.

How I treat von Willebrand disorders in older adults

ABSTRACT

von Willebrand disease (VWD) is the most common bleeding disorder and especially milder type 1 VWD might not be cared for in specialty clinics. VW factor levels rise with age, but the rise of these levels does not necessarily correlate with bleeding risk. A recent bleeding history combined with recent labs are important for hemostatic management decision during surgical interventions. Antifibrinolytics appear safe in the population of older adults, whereas desmopressin (DDAVP) should be used cautiously. Where needed, factor concentrates present a great treatment option. Acquired von Willebrand syndrome is vastly underrecognized, but likely to surface in the aging, especially in the setting of comorbidities, such as plasma-cell dyscrasias. Intravenous immunoglobulin can be an effective treatment in this scenario, but potentially increases thrombotic risk.

Common pathway coagulopathy and hemorrhagic edema of infancy

When screening tests of haemostasis are abnormal, it is important to identify at which point in the coagulation cascade dysfunction may be occurring. This may assist to identify a specific deficiency/dysfunction, the type of bleeding to be anticipated, and replacement therapy if required. Unmasking of an inherited coagulopathy or the development of an acquired coagulopathy may occur in the setting of a second (febrile) illness. Differentiating between inherited and acquired coagulopathies will rely on clinicians taking a thorough personal and family bleeding history, and correlating these findings with the haemostasis screening results.

VHrare study: Prevalence, clinical features and management of severe rare bleeding disorders in a large cohort

INTRODUCTION

Rare bleeding disorders (RBD) constitute 5% of total hereditary bleeding disorders, although the number could be higher, due to the presence of undiagnosed asymptomatic patients. The objective of this study was to analyze the prevalence and characteristics of patients with severe RBDs in our area.

MATERIAL AND METHODS

We analyzed the patients with RBD followed at a tertiary-level hospital between January 2014 and December 2021.

RESULTS

A total of 101 patients were analyzed, with a median age at diagnosis of 27.67 years (range 0-89), of which 52.47% were male. The most frequent RBD in our population was FVII deficiency. Regarding the diagnostic reason, the most frequent cause was a preoperative test and only 14.8% reported bleeding symptoms at the time of diagnosis. A genetic study was carried out in 63.36% of patients and the most frequent mutation type found was finding a missense mutation.

CONCLUSIONS

The distribution of RBDs in our centre is similar to the one reported in the literature. The majority of RBDs were diagnosed from a preoperative test and this allowed preventive treatment prior to invasive procedures to avoid bleeding complications. 83% of patients did not have a pathological bleeding phenotype according to ISTH-BAT.

Intracranial Hematoma After Ventriculoperitoneal Shunt Placement in a Patient With Factor V Deficiency: A Rare Case Report

Congenital factor V deficiency (FVD) is a rare bleeding disorder due to an inherited mutation. So far, there are no standard protocols for pre- and peri-operative management of patients with factor V deficiency. This poses a challenge for surgeons and requires a multidisciplinary approach. We present a case of a 60-year-old woman with factor V deficiency admitted to the neurosurgery department of Ibn Tofail Hospital for hydrocephalus requiring a ventriculoperitoneal shunt. Pre-operative management of the patients as well as outcome and follow-up are described and compared with relevant literature.

Analysis of 363 Genetic Variants in F5 via an Interactive Web Database Reveals New Insights into FV Deficiency and FV Leiden

The inherited bleeding disorder Factor V (FV) deficiency and clotting risk factor FV Leiden are associated with genetic variants in the F5 gene. FV deficiency occurs with mild, moderate, severe, or asymptomatic phenotypes, and either dysfunctional or reduced amounts of plasma FV protein. Here we present an interactive web database containing 363 unique F5 variants derived from 801 patient records, with 199 FV deficiency-associated variants from 245 patient records. Their occurrence is rationalized based on the 2,224 residue sequence and new FV protein structures. The 199 FV deficiency variants correspond to 26 (13%) mild, 22 (11%) moderate, 49 (25%) severe, 35 (18%) asymptomatic, and 67 (34%) unreported phenotypes. Their variant distributions in the FV domains A1, A2, A3, B, C1 and C2 were 28 (14%), 32 (16%), 34 (17%), 42 (21%), 16 (8%), and 19 variants (10%), respectively, showing that these six regions contain similar proportions of variants. Variants associated with FV deficiency do not cluster near known protein-partner binding sites, thus the molecular mechanism leading to the phenotypes cannot be explained. However, the widespread distribution of FV variants in combination with a high proportion of buried variant residues indicated that FV is susceptible to disruption by small perturbations in its globular structure. Variants located in the disordered B domain also appear to disrupt the FV structure. We discuss how the interactive database provides an online resource that clarifies the clinical understanding of FV deficiency.

Recurrent miscarriage in a woman with congenital factor V deficiency: a case report

BACKGROUND

Factor V deficiency is a rare bleeding disorder that can be either congenital or acquired. Factor V deficiency mostly present with mucosal bleeding. Coagulation factor V does not increase considerably during normal gestation. Since pregnancy can be threatened by blood clotting disorders, abnormal changes in coagulation factors level can pose challenges to pregnant women.

CASE PRESENTATION

We report a 40-year-old pregnant woman with prolonged gingival bleeding and epistaxis at 28 weeks of pregnancy. Her past medical history included two unexplained abortions. Physical examination was unremarkable, but the blood test showed elevated PT and PTT with a considerable decrease in factor V activity, while other factors were within normal range. Subsequently, the patient was diagnosed with congenital factor V deficiency. After treatment with fresh frozen plasma, she underwent vaginal delivery and a baby with factor V deficiency was born.

CONCLUSIONS

This is the second report of recurrent miscarriage in congenital factor V deficiency patients. Clinicians should consider the possibility of factor V deficiency in women with a history of idiopathic miscarriage even in patients without any symptoms.

Recurrent bleeding after posthemorrhoidectomy caused by factor V deficiency: a case report and review of the literature

Congenital factor V (FV) deficiency is a rare hemorrhagic disorder that can cause excessive bleeding during and after surgery in the affected patient. This report is the case of a patient who had FV deficiency with recurrent posthemorrhoidectomy bleeding treated with the hemostatic procedure and fresh frozen plasma (FFP) transfusions. A 45-year-old male patient had previously undergone hemorrhoidectomy for multiple hemorrhoids at a local hospital. Hemorrhoidectomy was successful; however, he was transferred to our hospital for evaluation of the origin of the recurrent posthemorrhoidectomy bleeding and underwent a hemostatic procedure. This bleeding was treated with coagulation using electrocautery, multiple sutures, and FFP transfusion (1,600 mL/day) for 7 consecutive days. The patient's plasma FV activity was 23%. Early detection of clotting factor deficiency in patients with hemorrhagic events after surgical treatments may prevent unnecessary procedures such as reoperations and minimize the cost of replacement therapy such as large-volume FFP transfusion.

Laparoscopic hepatectomy for hepatocellular carcinoma in a patient with congenital factor V deficiency: a case report

BACKGROUND

Factor V (FV) deficiency is an extremely rare disease, with an incidence of 1 in 1 million. The bleeding symptoms are mild, and the prognosis is good; however, the safety of surgical treatment is unclear, because there are few available reports. Herein, we report a case of hepatocellular carcinoma with congenital FV deficiency in a patient who safely underwent laparoscopic hepatectomy.

CASE PRESENTATION

A 79-year-old man, diagnosed with hepatocellular carcinoma of liver segment 5, with type C cirrhosis and sustained virological response visited our hospital. He had congenital FV deficiency, and blood tests showed coagulation deficiencies with an FV activity of < 2.6%, prothrombin time activity of 11%, and activated partial thromboplastin time of 100.3 s. Surgery and radiofrequency ablation were considered for treatment. Since the tumor was in contact with the Glissonean pedicle 5 + 6, surgery was judged to be superior from the viewpoint of safety and curability. After discussing the safety of the surgery with a hematologist, it was determined that the operation could be performed safely by transfusing sufficient fresh frozen plasma (FFP). Laparoscopic hepatic segment 5 + 6 subsegmental resection was performed with FFP transfusion, fluid restriction, airway pressure control, and central venous pressure reduction to control the bleeding. Bleeding was minimized during the transection of the liver parenchyma and no bleeding tendency was observed. The operative time was 445 min, and the amount of intraoperative bleeding was 171 mL. No complications, such as postoperative bleeding, were observed, and the patient was discharged on the eighth postoperative day.

CONCLUSIONS

Liver surgery can be performed safely in FV-deficient patients with strict coagulation capacity monitoring and appropriate transfusion of FFP. Preoperative evaluation of cardiac function to determine tolerance to high doses of FFP and ingenuity of surgery and intraoperative management to minimize blood loss are important.

Evaluating for Suspected Child Abuse: Conditions That Predispose to Bleeding

Child abuse might be suspected when children present with cutaneous bruising, intracranial hemorrhage, or other manifestations of bleeding. In these cases, it is necessary to consider medical conditions that predispose to easy bleeding or bruising. When evaluating for the possibility of bleeding disorders and other conditions that predispose to hemorrhage, it is important for pediatricians to consider the child's presenting history, medical history, and physical examination findings before initiating a laboratory investigation. Many medical conditions can predispose to easy bleeding. Before ordering laboratory tests for a disease, it is useful to understand the biochemical basis and clinical presentation of the disorder, condition prevalence, and test characteristics. This technical report reviews the major medical conditions that predispose to bruising or bleeding and should be considered when evaluating for abusive injury.

A Novel Phenotype of the Factor 5 Gene Mutation (Homozygote Met1736Val and Heterozygote Asp68His) Is Associated With Moderate Factor V Deficiency

Background

Factor V (FV) deficiency is a rare disease, with a low incidence rate in Asia. Therefore, the F5 mutation in the Taiwanese population is poorly understood.

Methods

A Chinese family with FV deficiency was included, and the patient and his family members underwent mutation analysis. Then, patients from Keelung City (Taiwan) were screened for F5 polymorphism; the Chang Gung Human Database was used to determine single-nucleotide variants in the non-FV-deficient patient population.

Results

Eight mutation sites on the F5 gene locus, including exon 16 homozygote Met1736Val and seven heterozygous mutations, including Asp68His, were found. Moreover, Met1736Val was found to be the dominant mutation in people living in the Taiwan community, and this result was compared with the records of the Chang Gung Human Database. The above-mentioned polymorphisms may result in a variable incidence of FV deficiency in Keelung City, thereby facilitating carrier diagnosis and prenatal diagnosis in most FV-deficient families.

Conclusion

The homozygote Met1736Val and the co-inheritance of the Asp68His F5 gene are unique and worthy of screening in FV-deficient patients.

Case Report: Novel Mutation of F5 With Maternal Uniparental Disomy Causes Severe Congenital Factor V Deficiency

We summarized two cases of congenital factor V deficiency (FVD) associated with a novel F5 mutation, and analyzed the relationship of the clinical features and genetic characteristics in congenital FVD. Case 1 was a female newborn infant with remarkable bleeding who died of severe intracranial hemorrhage on day 42 after birth. She had significant prolongation of prothrombin time (PT) and activated partial thromboplastin time (APTT). The percentage activity of FV (PFV) was lower than 3% in case 1. The mother of case 1 showed no tendency to bleed. She had mild prolongation of PT and APTT. The PFV was only 43%. Both cases were found to have the same novel mutation in F5, which was c.5419G>A (p.Ala1807Thr) in exon 16. The variant in case 1 was inherited from the mother of case 1. Whole-exome sequencing (WES) also found a splice site mutation: a 103 Mb maternal uniparental disomy (UPD) of 1q21.1-qter in case 1, in which the F5 gene is located in this segment. So case 1 was homozygote and the mother of case 1 was heterozygote. The novel mutation of F5 was predicted to be harmful by bioinformatics software including Sorting Intolerant From Tolerant (SIFT), Polyphen2, LRT, and Mutation Taster. In summary, c.5419G>A (p.Ala1807Thr) in exon 16 of F5 is a pathogenic mutation, which causes severe congenital FVD in homozygote patients.

Clinical Phenotype and Genetic Analysis of Twins With Congenital Coagulation Factor V Deficiency

OBJECTIVE

The aim was to investigate the clinical characteristics and molecular pathogenic mechanism of twins with congenital factor V (FV) deficiency.

METHODS

We comprehensively analyzed the clinical manifestations and laboratory test results of a set of twins and their parents and performed point mutation analysis with direct high-throughput exon sequencing.

RESULTS

The prothrombin time and activated partial thromboplastin time were prolonged for both probands, and the FV activity levels were 13.0% and 9.8%. Next-generation sequencing showed that the affected individuals harbored a paternal c.5113A>C (p.S1705R) and a maternal c.4949C>T (p.A1650V) heterozygous variants in the FV gene, which conformed to an autosomal recessive inheritance pattern. This is the first report of these point mutations. The older boy also had a congenital patent foramen ovale.

CONCLUSION

In this set of twins, missense mutations of the FV gene were related to congenital FV deficiency but unrelated to the patent foramen ovale observed in the older boy.

Measurement of coagulation factor antibody levels is useful for diagnosis and determining therapeutic efficacy in hemorrhagic patients with autoantibodies to coagulation factor VIII and factor V: results from a single center in Japan

Coagulation factor inhibitors (CFIs) sometimes cause fatal bleeding conditions. Determination of an inhibitor titer (INH-titer) using the Bethesda method is essential for diagnosing diseases associated with CFIs and examining the effects of immunosuppressive therapy. We reviewed 17 cases with CFIs (acquired hemophilia A, n = 11; FV inhibitor, n = 6) to examine the usefulness of determining quantities of an autoantibody to a coagulation factor (CF-IgG) by ELISA for diagnosis and therapeutic efficacy, as compared with INH-titer. One patient with an INH-titer and no evidence of CF-IgG was lupus anticoagulant (LA)-positive, and thus the positive INH-titer may have been a false positive caused by LA. Although INH-titer alone was insufficient to correctly identify patients with CFI, determination of CF-IgG appeared to be useful. In addition, even after INH-titer disappearance, hemorrhagic conditions recurred when CF-IgG was detected. These findings suggest that the presence of a clearance antibody against the coagulation factor might reduce the activity of that coagulation factor even after disappearance of the corresponding neutralizing antibody. Although the diagnosis and therapeutic efficacy can also be determined by INH-titer disappearance and improvement of corresponding coagulation factor activity, determination of CF-IgG by ELISA can improve the accuracy of these assessments.

Acquired Coagulation Factor V Inhibitor That Was Successfully Treated with Oral Corticosteroid Therapy

Acquired coagulation factor V (FV) inhibitors are rare disorders in which antibodies against FV develop under various conditions. We herein report the case of a 71-year-old woman with FV inhibitor during radiochemotherapy for pancreatic cancer. Multiple purpuras suddenly appeared on her bilateral upper limbs with prolonged coagulation data (APTT 97.3 seconds). The FV activity was less than 3% and the FV inhibitor was positive (1.7 B.U./mL). Oral prednisolone induced a rapid normalization of the coagulation data and FV activity and a rapid disappearance of FV inhibitor within 7 days. Early diagnosis and treatment may therefore be important in cases of FV inhibitor.

RNAi targeting heparin cofactor II promotes hemostasis in hemophilia A

Hemophilia A is a hemorrhagic disease due to congenital deficiencies of coagulation factor VIII (FVIII). Studies show that hemophilia patients with anticoagulant deficiency present less severe hemorrhagic phenotypes. We aimed to find a new therapeutic option for hemophilia patients by RNA interference (RNAi) targeting heparin cofactor II (HCII), a critical anticoagulant protein inactivating the thrombin. The optimal small interfering RNA (siRNA) was conjugated to an asialoglycoprotein receptor ligand (N-acetylgalactosamine [GalNAc]-HCII), promoting targeted delivery to the liver. After administration, GalNAc-HCII demonstrated effective, dose-dependent, and persistent HCII inhibition. After 7 days, in normal mice, GalNAc-HCII reduced HCII levels to 25.04% ± 2.56%, 11.65% ± 2.41%, and 6.50% ± 1.73% with 2, 5, and 10 mg/kg GalNAc-HCII, respectively. The hemostatic ability of hemophilia mice in the GalNAc-HCII-treated group significantly improved, with low thrombus formation time in the carotid artery thrombosis models and short bleeding time in the tail-clipping assays. After repeated administration, the prolonged activated partial thromboplastin time (APTT) was reduced. A 30 mg/kg dose did not cause pathological thrombosis. Our study confirmed that GalNAc-HCII therapy is effective for treating hemophilia mice and can be considered a new option for treating hemophilia patients.

Factor V Deficiency (Owren's Disease) in a Patient at High Risk for Transfusion-Associated Circulatory Overload and Bleeding During Laser Lead Extraction

Congenital factor V deficiency is an extremely rare abnormality and may be associated with significant bleeding as a result of trauma or surgery. Perioperative management primarily includes the administration of fresh frozen plasma to replace the deficient clotting factor. Acute administration of multiple blood products is a risk factor for transfusion-associated circulatory overload. Herein, the case of a 71-year-old man with an ejection fraction of 13% and a history of congenital factor V deficiency who was at risk for significant bleeding and transfusion-associated circulatory overload who underwent successful complex extraction of a right atrial pacing lead is reported.

Quantitative proteomics analysis of Angiostrongylus vasorum-induced alterations in dog serum sheds light on the pathogenesis of canine angiostrongylosis

Blood contains hundreds of proteins, reflecting ongoing cellular processes and immune reactions. Infections with the blood-dwelling cardiopulmonary nematode Angiostrongylus vasorum in dogs manifest with a broad spectrum of clinical signs including respiratory distress, bleeding diathesis and neurological signs, and are associated with a perturbed blood protein profile in dogs. However, current knowledge does not completely explain the observed pathologies induced by A. vasorum infections, including bleeding disorders. Using sera from experimentally infected dogs, dog serum proteome was analysed by quantitative mass spectrometry methods over several time points before and after inoculation. Following computational analysis, we identified 139 up- and downregulated proteins after infection (log2 ratio cut-off ≥ 1.0; q-value ≤ 0.05). Among upregulated proteins were chitinase 3-like 1 and pulmonary surfactant-associated protein B (log2 fold-changes ≥ 5). Pathway enrichment revealed the complement (especially the lectin pathway) and coagulation cascades as significantly affected upon analysis of downregulated proteins. Among them were mannan-binding lectin serine peptidases, ficolin, and coagulation factor XIII-B. These results bring new elements towards understanding the underlying pathomechanisms of bleeding diatheses observed in some A. vasorum-infected dogs.

Transfusion in Neonatal Patients: Review of Evidence-Based Guidelines

Transfusion of red blood cells, platelets, and fresh frozen plasma in neonatal patients has not been well characterized in the literature, with guidelines varying greatly between institutions. However, anemia and thrombocytopenia are highly prevalent, especially in preterm neonates. When transfusing a neonatal patient, clinicians must take into consideration physiologic differences, gestational and postnatal age, congenital disorders, and maternal factors while weighing the risks and benefits of transfusion. This review of existing literature summarizes current evidence-based neonatal transfusion guidelines and highlights areas of current ongoing research and those in need of future studies.

Successful Management of Life-threatening Pelvic Hemorrhage From Acquired Factor V Deficiency With immunosuppressive Therapy

Acquired Factor V deficiency is a rare and challenging condition to treat. It has been associated with major surgeries, antibiotics, blood transfusions, infections, autoimmune disorders, malignancy and exposure to bovine thrombin. The clinical presentation can be heterogeneous and can manifest as asymptomatic laboratory abnormalities to fatal hemorrhage with mortality rates around 15-20% . We report a case of acquired factor V deficiency in which the patient developed a life-threatening bleeding coagulopathy with elevated prothrombin time, activated partial thromboplastin time and factor V inhibitor titers following multiple surgical procedures that were performed after a motor vehicle accident. The patient was successfully treated with immunosuppressive therapy including steroids and cyclophosphamide resulting in the complete elimination of inhibitor levels.

Comprehensive N- and O-glycosylation mapping of human coagulation factor V

BACKGROUND/OBJECTIVE

Coagulation factor V (FV), a multidomain glycoprotein, is an essential cofactor in the blood clotting cascade. FV deficiency is a rare bleeding disorder that results in poor clotting after an injury or surgery. The only treatment for the disease is infusions of fresh frozen plasma and blood platelets. Glycosylation affects the biological activity, pharmacokinetics, immunogenicity, and in vivo clearance rate of proteins in the plasma. The glycan profile of FV, as well as how it affects the activity, stability, and immunogenicity, remains unknown.

METHODS

In this study, we comprehensively mapped the glycosylation patterns of human plasma-derived FV by combining multienzyme digestion, hydrophilic interaction chromatography enrichment of glycopeptides, and alternated fragmentation mass spectrometry analysis.

RESULTS/CONCLUSION

A total of 57 unique N-glycopeptides and 51 O-glycopeptides were identified, which were categorized into 40 N-glycan and 17 O-glycan compositions. Such glycosylation details are fundamental for future functional studies and therapeutics development. In addition, the established methodology can be readily applied to analyze glycosylation patterns of proteins with more than 2000 amino acids.

Analysis of factor V in zebrafish demonstrates minimal levels needed for early hemostasis

In humans, coagulation factor V (FV) deficiency is a rare, clinically heterogeneous bleeding disorder, suggesting that genetic modifiers may contribute to disease expressivity. Zebrafish possess many distinct advantages including high fecundity, optical clarity, external development, and homology with the mammalian hemostatic system, features that make it ideal for genetic studies. Our aim was to study the role of FV in zebrafish through targeted mutagenesis and apply the model to the study of human F5 variants. CRISPR-mediated genome editing of the zebrafish f5 locus was performed, generating mutants homozygous for a 49 base pair deletion in exon 4. Thrombus formation secondary to vascular endothelial injury was absent in f5 ^-/- mutant embryos and larvae. Despite this severe hemostatic defect, homozygous mutants survived before succumbing to severe hemorrhage in adulthood. Human F5 variants of uncertain significance from patients with FV deficiency were evaluated, and the causative mutations identified and stratified by their ability to restore thrombus formation in larvae. Analysis of these novel mutations demonstrates variable residual FV function, with minimal activity being required to restore hemostasis in response to laser-induced endothelial injury. This in vivo evaluation may be beneficial for patients whose factor activity levels lack correlation with bleeding symptomatology, although limitations exist. Furthermore, homozygous mutant embryos tolerate what is a severe and lethal defect in mammals, suggesting the possibility of species-specific factors enabling survival, and allowing further study not possible in the mouse. Identification of these factors or other genetic modifiers could lead to novel therapeutic modalities.

Congenital factor V deficiency from compound heterozygous mutations with a novel variant c.2426del (p.Pro809Hisfs*2) in the F5 gene: A case report

INTRODUCTION

Congenital factor V deficiency (FVD) is a rare bleeding disorder characterized by low or undetectable plasma factor V (FV) levels leading to mild to severe bleeding symptoms. Currently, more than 100 mutations have been reported in F5. We herein report a patient with FVD from mutations in the F5 gene.

PATIENT CONCERNS

A 52-year-old man with prolonged prothrombin time and activated partial thromboplastin time corrected by mixing test on preoperative screening. His past medical or family history was not remarkable.

DIAGNOSIS

Factor assays revealed a markedly reduced FV activity at 7%. Other factors were not decreased. DNA sequencing analysis to detect F5 gene mutations showed the patient was compound heterozygous for c.286G>C (p.Asp96His) and c.2426del (p.Pro809Hisfs*2). Asp96His was previously described missense mutation and Pro809Hisfs*2 was a novel deleterious mutation.

INTERVENTIONS

Fresh-frozen plasma was administered to supplement FV before surgery.

OUTCOMES

Subsequent factor assays revealed temporarily increased FV activity at 33%.

CONCLUSION

As was the case in our patient, genotype-phenotype correlations are poor in FVD, and molecular genetic test is necessary to confirm the diagnosis.

The use of prophylaxis in the treatment of rare bleeding disorders

Rare bleeding disorders (RBDs) are a heterogeneous group of coagulation factor deficiencies that include fibrinogen, prothrombin, α₂-antiplasmin, plasminogen activator inhibitor-1, and factors II, V, V/VIII, VII, X, XI and XIII. The incidence varies based upon the disorder and typically ranges from 1 in 500,000 to 1 per million population. Symptoms vary with the disorder and residual level of the clotting factor, and can range from relatively minor such as epistaxis, to life threatening, such as intracranial hemorrhage. Rapid treatment of bleeding episodes in individuals with severe bleeding phenotypes is essential to preserve life or limb and to prevent long-term sequelae; therapeutic options depend on the deficiency and range from plasma-derived (eg, fresh frozen plasma, prothrombin complex concentrates, factor X concentrate) to highly purified and recombinant single factor concentrates. The rarity of these disorders limits the feasibility of conventional prospective clinical trials; instead, clinicians rely upon registries, published case reports/series and experience to guide treatment. In some disorders, long-term prophylactic therapy is administered in response to the bleeding phenotype in an individual patient or based on the known natural history and severity of the deficiency. Intermittent prophylaxis, surrounding surgery, pregnancy, labor, and menstruation may be required to prevent or control excessive bleeding. This review summarizes therapeutic options, guidelines, recommendations and observations from the published literature for long-term, surgical, gynecological, and obstetric prophylaxis in deficiencies of fibrinogen; prothrombin; factors II, V, V/VIII, VII, X, XI and XIII; combined vitamin-K dependent factors; α2-antiplasmin; and plasminogen activator inhibitor 1. Platelet disorders including Glanzmann's thrombasthenia and Bernard-Soulier syndrome are also addressed.

Serum Factor V Is a Continuous Biomarker of Graft Dysfunction and a Predictor of Graft Loss After Liver Transplantation

BACKGROUND

Factor V has never been compared to a validated early allograft dysfunction (EAD) definition. We aimed to assess factor V as a biomarker of EAD and a predictor of graft loss after liver transplantation (LT).

METHODS

We retrospectively assessed the serum factor V levels on postoperative day 1 after LT. Patients were divided according to their factor V levels into the ≤36.1 U/mL and > 36.1 U/mL groups. The primary outcome was graft loss within 1, 3, and 6 months. The secondary outcome was EAD, as defined by Olthoff et al. Predictors of outcomes were identified by multivariable logistic regression.

RESULTS

Two hundred twenty-seven patients were included in the study: 74 with factor V of 36.1 U/mL or less and 153 with factor V >36.1 U/mL. EAD was diagnosed in 41 (55.4%) of 74 patients with factor V of 36.1 U/mL or less and in 20/153 (13.1%) patients with factor V >36.1 U/mL (P < 0.001). According to the multivariable regression model, factor V was a continuous marker of EAD (odds ratio [OR], 0.96; 95% confidence interval [CI], 0.94-0.98 per U/mL). Among the study groups, the 1-, 3-, and 6-month graft survival rates were 82%, 74%, and 74%, respectively, for patients with factor V of 36.1 U/mL or less and 98%, 95%, and 95%, respectively, for patients with factor V >36.1 U/mL (P = 0.001). Factor V was a continuous predictor for 3- and 6-month graft losses (OR, 0.96; 95% CI, 0.94-0.99 and OR, 0.97; 95% CI, 0.94-0.99 per U/mL), whereas EAD was not significant when adjusted for factor V.

CONCLUSION

Factor V is an early marker for EAD and is a continuous predictor of short-term graft loss after LT.

Perioperative Management of a Patient with Severe Factor V Deficiency Presenting with Chronic Subdural Hematoma: A Clinical Report

BACKGROUND

Severe factor V deficiency is an extremely rare coagulation disorder. Patients with factor V activity <5% usually become symptomatic in early childhood.

CASE DESCRIPTION

We report the case of an 82-year-old woman with incidentally diagnosed severe factor V deficiency, who developed a symptomatic chronic subdural hematoma, requiring burr hole craniostomy. Successful management was achieved by a multidisciplinary approach. Preoperatively, factor V activity was increased from 2% to 50% by administration of 25 mL/kg body weight of fresh frozen plasma over 30 minutes under close cardiopulmonary monitoring in the intensive care unit. Straight afterward, the patient was transferred to the operating room where surgery was performed under general anesthesia. Burr hole craniostomy could be performed without perioperative complications. In the postoperative days, there was no relevant recurrence of the subdural hematoma in the follow-up computed tomography scans under frequent control of coagulation parameters. However, despite further transfusion of fresh frozen plasma, factor V activity did not increase >16%. The patient was discharged without any neurologic deficits. In a hemostaseologic follow-up 2 months after surgery, factor V activity <1% was confirmed with evidence of a factor V inhibitor in the modified Bethesda assay. Most likely, the patient suffered from an acquired form of factor V deficiency with preformed antibodies that had been boosted by the initial treatment with fresh frozen plasma.

CONCLUSIONS

We conclude that in this rare bleeding disorder, intracranial surgery was successfully managed because of a thoroughly planned perioperative therapeutic strategy. However, if there is time prior to surgery, a full checkup of the bleeding disorder is advisable.

Meta-Analysis of Factor V, Factor VII, Factor XII, and Factor XIII-A Gene Polymorphisms and Ischemic Stroke

Numerous studies examined the association between factors FV, FVII, FXII, and FXIII-A gene polymorphisms and ischemic stroke, but conclusive evidence is yet to be obtained. Thus, this meta-analysis aimed to investigate the novel association of FV rs1800595, FVII rs5742910, FXII rs1801020, and FXIII-A rs5982 and rs3024477 polymorphisms with ischemic stroke risk. A systematic review was performed on articles retrieved before June 2018. Relevant data were extracted from eligible studies and meta-analyzed using RevMan version 5.3. The strength of association between studied polymorphisms and ischemic stroke risk was calculated as odds ratios and 95% confidence intervals, by applying both fixed- and random-effect models. A total of 25 studies involving 6100 ischemic stroke patients and 9249 healthy controls were incorporated in the final meta-analysis model. Specifically, rs1800595, rs5742910, rs1801020, rs5982, and rs3024477 consisted of 673, 3668, 922, 433, and 404 cases, as well as 995, 4331, 1285, 1321, and 1317 controls, respectively. The pooled analysis indicated that there was no significant association of FV rs1800595, FVII rs5742910, FXII rs1801020, FXIII-A rs5982, and FXIII-A rs3024477 polymorphisms with ischemic stroke risk, under any genetic models (dominant, recessive, over-dominant, and allelic). The present meta-analysis concluded that FV rs1800595, FVII rs5742910, FXII rs1801020, and FXIII-A rs5982 and rs3024477 polymorphisms are not associated with ischemic stroke risk.

Management of Single Uncomplicated Dental Extractions and Postoperative Bleeding Evaluation in Patients With Factor V Deficiency: A Local Antihemorrhagic Approach

PURPOSE

The aim of the present study was to analyze the management of single dental extractions and postoperative bleeding in patients with a diagnosis of factor V deficiency. A careful evaluation of each case will allow the team to categorize the risk and operate safely, minimizing the incidence of intraoperative and postoperative complications. If necessary, the oral-maxillofacial surgeon can choose to do so in collaboration with the hematologist on a case-by-case basis.

PATIENTS AND METHODS

The present retrospective study included 5 patients with mild congenital factor V deficiency who had undergone at least 1 dental extraction. Mouth rinse with tranexamic acid, nonresorbable sutures, and gelatin sponge packed in the alveolar socket were used to obtain hemostasis. No systemic therapies, such as fresh frozen plasma, platelet concentrate, or recombinant activated factor VII, were administered.

RESULTS

Twenty-five teeth were extracted. The factor V plasma levels ranged from 14.1 to 22.4%. Local antihemorrhagic treatments resulted in good hemostasis. No hemorrhagic complications or intraoperative or postoperative major bleeding was observed.

CONCLUSIONS

Dental extractions appear to be safe procedures for patients with mild factor V deficiency when a bleeding risk assessment has been performed in conjunction with a hematologist and an appropriate treatment protocol is followed. Our treatment protocol was found to be effective and well tolerated by all the patients.

Factor V levels and risk of venous thrombosis: The MEGA case-control study

BACKGROUND

Blood coagulation levels are associated with risk of venous thrombosis (VT). The role of factor (F)V is ambiguous since it plays a dual role in coagulation: it has a procoagulant role when it serves as a cofactor for the activation of thrombin and it has an anticoagulant role by enhancing the inactivation of activated FVIII.

OBJECTIVES

To elucidate the association of FV levels with risk of VT.

PATIENTS/METHODS

We analyzed FV antigen levels in 2377 patients with VT and 2943 controls from the MEGA study. FV levels were categorized according using the 1st, 2.5th, 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles of FV levels in controls as cut-off points. Odds ratios (ORs) were estimated using logistic regression models and adjusted for age and sex, liver disease, FVIII levels, FV Leiden, and TFPI.

RESULTS

The risk estimates were U-shaped with increased ORs for the lowest (<0.57 U/dL) levels (OR 1.46; 95% CI 0.87-2.43) as well as the highest (>1.22 U/dL) (OR 1.86; 95% CI 1.46-2.37) levels as compared with the reference group (25th-50th percentile). FVIII adjustment led to attenuation of the OR for high FV levels (OR 1.14; 95% CI 0.88-1.48), with little change for low FV levels (OR 1.68; 95% CI 0.97-2.91). Other adjustments had limited effects.

CONCLUSIONS

We found high FV levels to be associated with increased risk for VT, which was explained by concurrently raised FVIII levels. For low levels of factor V, the increased risk for VT could not be explained by the mechanisms we explored.

High Titer of Acquired Factor V Inhibitor Presenting with a Pseudo-deficiency of Multiple Coagulation Factors

Acquired coagulation factor inhibitor is a rare coagulation disorder. We herein report a patient with acquired factor V inhibitor showing a decrease in multiple coagulation factor activities. A high titer of factor V inhibitor presumably led to a marked inhibition of factor V activity in the specific factor-deficient plasma used in coagulation factor activity assays based on either an activated partial thromboplastin time (APTT) or prothrombin time (PT) clotting assay, resulting in false low values of the coagulation activity. We re-examined the coagulation factor activity using several dilutions of the patient's plasma and confirmed that the high factor V inhibitor titer had caused an apparent decrease in multiple coagulation factor activities.

Management of intracranial hemorrhage in severe factor V deficiency and definitive treatment with liver transplantation

FV is primarily produced in the liver, and congenital FV deficiency is a disorder with an incidence of one in 1 million. Standard care is to treat severe bleeding phenotypes with FFP as there is no recombinant or plasma-derived FV concentrate. We present a case of a neonate with known severe FV deficiency diagnosed after prolonged bleeding after circumcision who represented at age 2 months with a large left intraparenchymal hemorrhage. His bleed was treated with FFP, platelet transfusion, recombinant VIIa, and emergent evacuation. He was maintained on plasma infusions but was unable to space his infusions beyond 48 hours. Liver transplantation was considered as a definitive treatment for this condition. While awaiting a suitable liver, his FV trough levels occasionally dropped below 5%, and he suffered from a second acute intracranial bleed. He received an orthotopic liver transplant at age 5 months, resulting in correction of his FV levels. He has not required any plasma infusions post-transplantation and has had no further bleeding episodes. Liver transplantation should be considered as definitive treatment early in the course for patients with severe FV deficiency and first time life-threatening bleed.

Successful Outcome of Severe Intra-cerebral Bleeding Associated with Acquired Factor V Inhibition: Utilization of Multiple Therapeutic Agents

Background:

Acquired coagulation factor inhibitors are antibodies that either inhibit activity or increase the clearance of a clotting factor and lead to an increased risk of bleeding. Most of the time, the disorder is attributed to factor VIII inhibition (acquired haemophilia A); however, other coagulation factors could also be implicated.

Case Report:

Herein, we report an interesting case of a patient who underwent coronary artery bypass grafting and received antibiotic treatment after surgery with third generation cephalosporin. A month later, he presented with extreme bleeding diathesis and cerebral haemorrhage. Following a thorough clinical and laboratory investigation, an acquired factor V inhibitor was diagnosed. The patient received treatment with corticosteroids, intravenous immunoglobulins, anti-CD20 monoclonal antibodies (rituximab), cyclophosphamide and recombinant factor VIIa. Finally, despite the poor initial prognosis, the patient managed to achieve a full recovery.

Conclusion:

As there are no clear guidelines on acquired coagulation inhibitor treatment, reports of such cases could offer insight for future therapy choices. The case was unique because the treatment regimen included a combination of multiple therapeutic agents including rituximab.

[Factor V congenital deficiency: about a case]

Le déficit congénital en facteur V est une anomalie rare de la coagulation, initialement décrite par Owren en 1947 et connue sous le nom de para hémophilie. Elle est transmise selon un mode autosomique récessif. En générale elle est symptomatique à l'état homozygote. Le facteur V est un cofacteur essentiel dans la conversion de la prothrombine en thrombine par le facteur X activé. En l'absence du facteur V, la génération de thrombine est ralentie et la formation de fibrine est retardée. Il en résulte une tendance aux saignements. Nous rapportons un cas de déficit congénital en facteur V chez un nourrisson présentant des épistaxis à répétition.

Phenotype Report on Patients with Congenital Factor V Deficiency in Southern Iran: Recent Ten Years' Experience

This study aimed to investigate clinical symptoms in patients with congenital factor V (FV) deficiency and the relationship between phenotype and factor activity level. Thirteen patients with congenital FV deficiency were investigated and the factor activity level and first clinical presentations were studied for each patient. The most common first signs and symptoms were post-surgery, post-partum, post-circumcision, and post-traumatic bleeding (30.76%), followed by easy bruising in 23.10% of the patients. The median age at the onset of clinical signs was 18 (range: 1-53) years. Patients were categorized into two groups of major and minor bleeding based on their first clinical bleeding symptoms. There was not a significant difference between the two groups with regard to factor activity level, age at diagnosis, prothrombin time, partial thromboplastin time, and international normalized ratio (p>0.05). There is a discrepancy between plasma FV activity level and the severity of clinical presentations.

Autosomal recessive inherited bleeding disorders in Pakistan: a cross-sectional study from selected regions

Background

Autosomal recessive bleeding disorders (ARBDs) include deficiencies of clotting factors I, II, V, VII, X, XI, XIII, vitamin K dependent clotting factors, combined factor V & VIII, Von Willebrand Disease (vWD) type 3, Glanzmann’s thrombasthenia (GT) and Bernard–Soulier syndrome. Patients with primary bleeding disorders from all the major provincial capitals of Pakistan were screened for ARBDs. Prothrombin (PT), activated partial thromboplastin time (APTT), bleeding time (BT) and fibrinogen levels were measured. Cases with isolated prolonged APTT were tested for factors VIII and IX using factor assays This was followed by FXI:C level assessment in cases with normal FVIII and FIX levels. vWD was screened in patients with low FVIII levels. Factors II, V and X were tested in patients with simultaneous prolongation of PT and APTT. Peripheral blood film examination and platelet aggregation studies were performed to assess platelet disorders. Urea clot solubility testing was done to detect Factor XIII levels where platelet function tests were normal. Descriptive analysis was done using SPSS version 16.

Results

Of the 429 suspected bleeding disorder patients, 148 (35%) were diagnosed with hemophilia A and 211 (49.1%) patients had ARBDs. 70 patients (16.3%) remained undiagnosed. Out of 211 patients with ARBD; 95 (33.8%) had vWD type 3. Fibrinogen deficiency was found in 34 patients (12%), GT in 27 (9.6%), factor XIII deficiency in 13 (4.6%), factor VII deficiency in 12 (4.3%), factor V deficiency in 9 (3.2%). Eight patients (2.8%) had vitamin K-dependent clotting factor deficiency, Bernard–Soulier syndrome was diagnosed in seven patients (2.5%), factor X deficiency in 2 (0.7%), factor II deficiency in 2 (0.7%), factor XI deficiency and combined factor V and VIII deficiency in 1 (0.4%) patient each.

Conclusion

vWD type 3 was the most common ARBD found in our sample of patients in Pakistan, followed by fibrinogen deficiency and GT in respective order.