Factor VII deficiency

Novel heterozygous F7 gene mutation (c. C1286T) associated with congenital factor VII deficiency: A case report and literature review

Background

Congenital factor VII (FVII) deficiency is a rare inherited autosomal recessive disorder characterized by prolongation of prothrombin time and low FVII coagulation activity, which may increase the risk of bleeding.

Case presentation

A 66‐year‐old man with acute postoperative intracranial hemorrhage was transferred to our hospital owing to coagulation dysfunction. In coagulation tests, the FVII coagulation activity was less than 2%. Genetic analysis of the gene encoding FVII identified compound heterozygous mutations: c. 681+1 G>T and c. C1286T (p. Ala429Val).

Conclusions

To our knowledge, this is the first report describing the c. C1286T (p. Ala429Val) mutation in the FVII‐encoding gene. We suggest that these mutations resulted in the reduced FVII activity and abnormal clotting in our patient after brain surgery.

A novel compound heterozygous variant linked to hematuria in a family with hereditary factor VII deficiency

BACKGROUND

Hereditary Factor VII Deficiency (FVIID) is a rare congenital autosomal recessive bleeding disorder. In clinical manifestations, its onset is caused by variant of the F7 gene (NM_019616) with strong heterogeneity. We identified a family with hematuria caused by a novel F7 compound heterozygous variant and studied the FVIID-dependent mechanism impacted by these variants.

METHODS

Coagulation factors in the proband were functionally verified. We located pathogenic variants in relevant genes using next-generation sequencing after target enrichment and verified them by Sanger sequencing. We examined the coagulation activity and secretion pattern of recombinant FVII variants expressed in cells and observed their location and stability by immunofluorescence.

RESULTS

We found a missense variant c.1207G>A (p.Gly403Ser) and a frameshift variant c.154_155del (p.Arg53fs) in the F7 gene of the proband. FVII activity tests showed that the variants significantly decreased its presence in the cell culture supernatant. Moreover, the R53fs mutant lacked the FVII functional domain and had no detectable activity. Immunofluorescence indicated that the p.Gly403Ser variant was distributed to the cell membrane and cytoplasm, while the FVII R53fs variant was not detected. Deficient FVII protein function and severe coagulation disorder are the likely causes of hematuria and other bleeding symptoms in the proband.

CONCLUSION

The newly discovered F7 gene variants enrich the spectrum of hereditary FVII deficiency and provide a new foundation for the diagnosis and treatment of this type of coagulation disorder.

Phenotypical variability in congenital FVII deficiency follows the ISTH-SSC severity classification guidelines: a review with illustrative examples from the clinic

Background

One of the most common rare inherited bleeding disorders, congenital factor VII (FVII) deficiency typically has a milder bleeding phenotype than other rare bleeding disorders. Categorizing severity in terms of factor activity associated with hemophilia (severe <1%, moderate 1%–5%, mild 6%–40%) has led to the observation that bleeding phenotype does not follow closely with FVII activity. Over the past decade, large-scale global registries have investigated bleeding phenotype more thoroughly. The International Society on Thrombosis and Haemostasis has reclassified FVII deficiency as follows: severe, FVII <10%, risk of spontaneous major bleeding; moderate, FVII 10%–20%, risk of mild spontaneous or triggered bleeding; mild, FVII 20%–50%, mostly asymptomatic disease.

Case reports

Eleven illustrative cases of congenital FVII deficiency adapted from clinical practice are described to demonstrate the variability in presentation and in relation to FVII activity levels. Severe FVII deficiency usually presents at a young age and carries the risk of intracranial hemorrhage, hemarthrosis, and other major bleeds. Moderate FVII deficiency tends to present later, often in adolescence and particularly in girls as they reach menarche. Milder disease may not be apparent until found incidentally on preoperative testing, during pregnancy/childbirth, or following unexplained bleeding when faced with hemostatic challenges.

Conclusion

It is important for health care professionals to be aware of the new definitions of severity and typical presentations of congenital FVII deficiency. Failure to appreciate the risks of major bleeding, including intracerebral hemorrhage in those with FVII activity <10%, may put particularly young children at risk.

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.

Surgical interventions in childhood rare factor deficiencies: a single-center experience from Turkey

Congenital rare factor deficiencies may present in infancy by life-threatening bleedings or may not show any symptoms until adulthood. It is reported more commonly in countries having consanguineous marriages. Data regarding surgical interventions of rare congenital factor deficiencies are based on case reports and records of guidelines. There are no well documented and separately prepared directories related to pre-surgical and prophylactic approaches of surgical interventions of these deficiencies. Our retrospective study consisted of 171 rare factor deficiencies that were followed up in our clinic, and of whom 61 had 88 surgical interventions between 1990 and 2012. Of these patients, 45 were having factor VII deficiency, and factor V, X, XI, XIII and fibrinogen deficiencies were present in five, four, three, two and two patients, respectively. In 23 patients, factor coagulant activities were under 5% (37.7%), in 15 it was between 5 and 30% (24.6%), and in 23 between 30 and 50% (37.7%). Twenty-eight were symptomatic and 33 were asymptomatic. Information of 51 (83.6%) male and 10 (16.4%) female patients with an age range of 5-25 years (13 ± 5.27), whose age at presentation ranged between 3 weeks and 18 years (7 ± 4.66), were retrieved from patient records and from the records contained in the data-processing environment introduced in 2005. The rate of familial consanguinity was 49.2%. Of the surgical interventions, 24 (27.3%) were major, 24 (27.3%) were minor and 40 (45.4%) were circumcision. We used fresh frozen plasma in 32, recombinant factor (rF)VIIa in 20, prothrombin complex concentrate in five and fibrinogen in three patients during surgical interventions. In 18 patients, antifibrinolytic agents were also used. In 27 patients, surgical interventions were applied without any replacement therapy. No additional doses were required after surgical prophylaxis doses. Thrombotic events were not observed. Antibody occurrence was not detected in these patients. In our study, we evaluated preparation for surgical procedures, factor replacement therapy before surgical intervention and postoperative follow-up in patients with rare coagulation factor deficiency.

Factor VII deficiency: a single-center experience

Congenital factor VII deficiency is the most common form of rare coagulation factor deficiencies. This article presents a retrospective evaluation of 73 factor VII deficiency cases that had been followed at our center. The study consisted of 48 males and 25 females (2 months-19 years). Thirty-one (42.5%) of them were asymptomatic. Out of symptomatic patients, 17 had severe clinical symptoms, whereas 8 presented with moderate and 17 with mild symptoms. The symptoms listed in order of frequency were as follows: epistaxis, petechia or ecchymose, easy bruising, and oral cavity bleeding. The genotype was determined in 8 patients. Recombinant activated factor VII (rFVIIa) was used to treat 49 bleeding episodes in 8 patients after 2002. In 2 patients with repeated central nervous system bleeding prophylaxis with rFVIIa was administered. No allergic and thrombotic events were observed during both treatment and prophylaxis courses. Antibody occurrence was not detected in the patients during treatment.

Familial factor VII deficiency with foetal and neonatal fatal cerebral haemorrhage associated with homozygosis to Gly180Arg mutation

Inherited factor VII (FVII) deficiency is a rare autosomal recessive disorder with a wide heterogeneous clinical pattern. Intracranial haemorrhage in infants has been previously reported in the severe form of the FVII deficiency and it has a high fatality rate. We report a family with high consanguineous relations, who experienced death of two baby girls, the first with prenatal manifestation of foetal hydrocephalus secondary to intracranial bleeding and the second with postnatal intracranial bleeding, both with less than 1% activity of FVII. Genetic analysis revealed that both parents are heterozygous and both daughters homozygous for a point mutation gG9639A in exon 7, predicting Gly180Arg substitution. This mutation was described previously in a compound heterozygous patient with mild bleeding manifestation. It seems that in this family, the mutation in its homozygous state is fatal and the lethal clinical expression can appear in utero at an early stage of gestation.

Recombinant Factor VIIa: A Review on Its Clinical Use

Recombinant activated factor VII (rFVIIa) (NovoSeven) is a novel hemostatic agent originally developed to treat bleeding episodes in hemophilic patients with inhibitors against coagulation factors VIII and IX. In recent years, rFVIIa has also been employed for the management of uncontrolled bleeding in a number of congenital and acquired hemostatic abnormalities. Based on a literature search including PubMed, references from reviews, and abstracts from the most important meetings on this topic, this review examines the current knowledge on therapy with rFVIIa, from the now well-standardized uses to the newer and less well-characterized clinical applications.

Severe FVII deficiency caused by a new point mutation combined with a previously undetected gene deletion

A 3-week-old Caucasian female presented with severe unprovoked parenchymal cerebral haemorrhage. Her plasma factor VII (FVII) activity was <0.01 units/ml. FVII activities for her mother and sister were 0.65 units/ml and 0.51 units/ml, respectively, while her father's level was normal. These results indicated that the mother was heterozygous for a non-functional F7 gene that had also been inherited by the proband's sister. The proband's severe FVII deficiency was caused by a new mutation in her paternal F7 gene coupled with the inheritance of the non-functional maternal F7 gene. DNA sequence analysis revealed that the proband had apparent homozygosity for a novel single point mutation (g.3907G >A) changing the codon for Glu29 to Lys (E29K); neither parent had the E29K mutation. Because of the unlikelihood that the proband was homozygous for two identical new point mutations, the DNA sequence abnormality was more likely to have arisen from a single mutated gene on one allele and a F7 gene deletion on the other allele. Real time polymerase chain reaction (PCR) analysis confirmed that the proband had inherited a gene deletion that was present in the maternal side of the family. Subsequent clotting assays and real time PCR revealed that the maternal deletion also included the closely linked F10 gene.