Factor VII deficiency: a single-center experience

Reproductive health and hemostatic issues in women and girls with congenital factor VII deficiency: A systematic review

BACKGROUND

Congenital factor VII (FVII) deficiency is an inherited bleeding disorder, with heterogenous bleeding symptoms. Women with FVII deficiency face hemostatic challenges during menstruation, ovulation, and childbirth. This systematic review evaluated prevalence and management of bleeding symptoms associated with gynecological and obstetric issues in women with FVII deficiency.

METHODS

Databases (BIOSIS Previews, Current Contents Search, Embase, and MEDLINE) were searched for studies reporting FVII deficiency and gynecological or obstetric issues in women. Articles were screened using Joanna Briggs Institute checklists and relevant data extracted.

RESULTS

One hundred fourteen women were identified from 62 publications. Forty-six women had severe deficiency (FVII:C < 5% or <5 IU/dl). Heavy menstrual bleeding (HMB) was the most common bleeding symptom (n = 94; 82%); hospitalization and urgent medical/surgical interventions for acute HMB episodes were required in 16 women (14%). Seven women reported ovarian bleeding (6%); other bleeding symptoms varied. Patient management was inconsistent and included hemostatic and hormonal treatments. Only four women (7%) reporting vaginal bleeding during pregnancy. Postpartum hemorrhage (PPH) occurred following 12/45 deliveries (27%; 5 [42%] requiring blood transfusion) and was not necessarily prevented by prophylaxis (8 women).

CONCLUSION

Women with congenital FVII deficiency have an increased risk of HMB, ovarian bleeding, and PPH, impacting quality of life. Recognition of a bleeding disorder as the cause is often delayed. Management of bleeding complications is heterogeneous due to lack of treatment guidelines. Harmonizing severity classification of FVII deficiency may help standardize treatment strategies and development of specific guidelines for these women.

Results of multicenter registry for patients with inherited factor VII deficiency in Turkey

INTRODUCTION

Inherited factor VII (FVII) deficiency (FVIID) is the most common of inherited rare bleeding disorders. Other determinants of clinical severity apart from FVII level (FVIIL) include genetic and environmental factors. We aimed to identify the cut-off FVIILs for general and severe bleedings in patients with FVIID by using an online national registry system including clinical, laboratory, and demographic characteristics of patients.

METHODS

Demographic, clinical, and laboratory data of patients with FVIID extracted from the national database, constituted by the Turkish Society of Hematology, were examined. Bleeding phenotypes, general characteristics, and laboratory features were assessed in terms of FVIILs. Bleeding rates and prophylaxis during special procedures/interventions were also recorded.

RESULTS

Data from 197 patients showed that 46.2% of patients had FVIIL< 10%. Most bleeds were of mucosal origin (67.7%), and severe bleeds tended to occur in younger patients (median age: 15 (IQR:6-29)). Cut-off FVIILs for all and severe bleeds were 16.5% and 7.5%, respectively. The major reason for long-term prophylaxis was observed as central nervous system bleeding (80%).

CONCLUSION

Our data are consistent with most of the published literature in terms of cut-off FVIIL for bleeding, as well as reasons for prophylaxis, showing both an increased severity of bleeding and younger age at diagnosis with decreasing FVIIL. However, in order to offer a classification similar to that in Hemophilia A or B, data of a larger cohort with information about environmental and genetic factors are required.

Function and regulation of corin in physiology and disease

Atrial natriuretic peptide (ANP) is of major importance in the maintenance of electrolyte balance and normal blood pressure. Reduced plasma ANP levels are associated with the increased risk of cardiovascular disease. Corin is a type II transmembrane serine protease that converts the ANP precursor to mature ANP. Corin deficiency prevents ANP generation and alters electrolyte and body fluid homeostasis. Corin is synthesized as a zymogen that is proteolytically activated on the cell surface. Factors that disrupt corin folding, intracellular trafficking, cell surface expression, and zymogen activation are expected to impair corin function. To date, CORIN variants that reduce corin activity have been identified in hypertensive patients. In addition to the heart, corin expression has been detected in non-cardiac tissues, where corin and ANP participate in diverse physiological processes. In this review, we summarize the current knowledge in corin biosynthesis and post-translational modifications. We also discuss tissue-specific corin expression and function in physiology and disease.

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.

Congenital factor VII deficiency in Iraqi children (Single Centre Experience)

Background and Objective

Factor VII (FVII) deficiency is probably one of the most common of the rare autosomal recessive coagulation disorders, with an estimated prevalence of l: 500000. All age groups can be affected with FVII deficiency. This study aimed to describe the demographic parameters, symptomatology, hemostatic values and the outcome of FVII deficiency.

Methods

This is a retrospective descriptive study of patients with congenital FVII deficiency over a period of seven years from (August 2008 to August 2015). The data were collected by reviewing the files for each patient diagnosed with FVII deficiency. Surgical interventions, complications and follow up visits were recorded.

Results

Twenty-four patients were included in this study, 17 females and seven males, below one year was the most common age at presentation. More than half of patients (58.3%) were diagnosed within six months of symptoms onset. The majority of patients had severe phenotype. The most common symptom was epitaxis (41.7%). Five out of 10 patients with FVII level < 1% have either mild to moderate phenotype of the disease without complications; while six out of 14 patients with FVII > 1% had at least one episode of severe bleeding. Three patients had hepatitis C; all were treated by blood products before the introduction of recombinant FVII in Iraq. The outcome of most patients (75%) was normal without complications at time of study.

Conclusion

Clinical manifestations of FVII deficiency are variable and they are not necessarily correlated to the FVII level.

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.

Congenital Factor Deficiencies in Children: A Report of a Single-Center Experience

Congenital factor deficiencies (CFDs) refer to inherited deficiency of coagulation factors in the blood. A total of 481 patients with CFDs, who were diagnosed and followed at our Pediatric Hematology and Oncology Clinic between 1990 and 2015, were retrospectively evaluated. Of the 481 cases, 134 (27.8%) were hemophilia A, 38 (7.9%) were hemophilia B, 57 (11.8%) were von Willebrand disease (vWD), and 252 (52.3%) were rare bleeding disorders (RBDs). The median age of the patients at the time of diagnosis and at the time of the study was 4.1 years (range: 2 months to 20.4 years) and 13.4 years (range: 7 months to 31.3 years), respectively. The median duration of the follow-up time was 6.8 years (range: 2.5 months to 24.8 years). One hundred nineteen (47.2%) of 252 patients with RBDs were asymptomatic, 49 (41.1%) of whom diagnosed by family histories, 65 (54.6%) through preoperative laboratory studies, and 5 (4.2%) after prolonged bleeding during surgeries. Consanguinity rate for the RBDs was 47.2%. Prophylactic treatment was initiated in 80 patients, 58 of whom were hemophilia A, 7 were hemophilia B, 13 were RBDs, and 2 were vWD. Significant advances have been achieved during the past 2 decades in the treatment of patients with CFDs, particularly in patients with hemophilias. The rarity and clinical heterogeneity of RBDs lead to significant diagnostic challenges and improper management. In this regard, multinational collaborative efforts are needed with the hope that can improve the management of patients with RBDs.

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.

Bleeding manifestations in heterozygotes with congenital FVII deficiency: a comparison with unaffected family members during a long observation period

OBJECTIVES

To determine whether heterozygotes with FVII deficiency have a bleeding tendency or not.

PATIENTS AND METHODS

Eighty-four patients (OK) heterozygous for FVII deficiency, at the onset of the study, were paired with unaffected family members and followed for a long period of time (mean 22.6 years) for the occurrence of bleeding. Diagnosis of heterozygosis had to be based on family studies, clotting, immunological assays and genetic analysis.

RESULTS

The mean FVII activity level was 0.51 IU/dl (range 35-65) and 94 IU/dl (range 88-118) in the heterozygotes and in the normal counterparts, respectively. Documented bleeding manifestations occurred in eight heterozygotes and in seven normal subjects. Statistical analysis of the difference was not significant. Bleeding manifestations were easy bruising, bleeding after tooth extractions, menorrhagia, epistaxis with no difference among the two groups. There was no strict correlation between bleeding and FVII activity levels.

CONCLUSIONS

The study indicates that heterozygotes for FVII deficiency show rare bleeding manifestations which are also present in the unaffected family members with normal FVII levels. This indicates that Factor VII activity levels played no role in the occurrence of the bleeding symptoms. Furthermore, FVII levels of around 0.40 IU/dl are capable of assuring a normal hemostasis.

How do we encounter rare factor deficiencies in children? Single-centre results from Turkey

BACKGROUND

Rare factor deficiencies (RFDs) are autosomal recessively inherited coagulation factor deficiencies encountered at a frequency of between one in 500, 000 and one in two million.

MATERIALS AND METHODS

One hundred and ninety-two patients, diagnosed as having RFD, followed and treated in our clinic between 1990 and 2013 were retrospectively evaluated in this study.

RESULTS

From the 192 patients, 142 had FVII, 15 had FX, 14 had FXI, 10 had fibrinogen, six had FV, two had FXIII, two had FV + FVIII and one had FII deficiency. One hundred and thirty of the cases were boys and 62 were girls. The age range was 2 weeks to 24 years and the ages at the admission were between 2 weeks and 16 years. The rate of consanguinity was 49.4%. Eighty-eight of our patients were asymptomatic (45.8%) and 104 were symptomatic (54.2%). Asymptomatic patients were diagnosed by family histories (39.8%), preoperative laboratory studies (54.6%) and operational bleeding (5.6%). Sixty-eight of our symptomatic patients displayed grade II (65.4%) and 36 displayed grade III bleeding symptoms (34.6%). First bleeding regions were skin (33%), nose (28%), central nervous system (CNS) (15.5%), oral cavity (10.5%), soft tissue (6%), joint (3%), urinary system (2%) and gastrointestinal system (GIS) (2%), respectively. The bleeding prevalence rates of our symptomatic patients are listed as epistaxis 62.5%, skin bleedings 53%, oral cavity bleeding 28.8%, haematomas 18.3%, CNS bleedings 17.3%, haemarthrosis 14.4%, GIS bleedings 3.8%, menorrhagia 2.9%, haematuria 1.9%, bleeding because of operations 1.9% and iliopsoas bleedings 1.9%. CNS bleedings (41%) take the first place among the serious bleedings of our cases, followed by haemarthrosis (36.4%), GIS bleedings (18.1%) and iliopsoas bleedings (4.5%). Prophylaxy was applied to nine patients (five patients with FVII, two patients with fibrinogen and one each with FV and FX deficiency).

CONCLUSIONS

The characteristics of clinical presentations, first bleeding attacks, bleeding prevalence and severe bleedings as well as prophylactic approaches are discussed in this article.

Congenital Factor VII Deficiency in Children at Tertiary Health Care Facility in Pakistan

This study presents the demographics, clinical spectrum, and outcome of patients with congenital factor VII (FVII) deficiency at a tertiary care center over a period of 12 years. Of the 49 patients, 27 (55%) patients were males. Consanguinity was found in 92% of the patients. The median age of symptom onset was 2.4 (interquartile range [IQR]: 1.1-6.5) years with a median age of 5.8 (IQR: 3.1-10) years at diagnosis. Life-threatening complications like intracranial bleeding (ICB) and intra-abdominal bleeding (IAB) were observed in 8 (16.4%) patients. We found that 11 (55%) of the 20 patients with FVII coagulant activity (FVIIc) <1% were either asymptomatic or showed mild phenotype. In contrast, 9 (53%) of the 17 patients with FVIIc >5% were affected by severe symptoms. Age <1 year was the only identified risk factor associated with development of life-threatening bleeding episodes (P = .042; odds ratio 6.46). Overall, 4 (8.2%) died as a consequence of ICB (3 patients) and IAB (1 patient).

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.

Prophylaxis in congenital factor VII deficiency: indications, efficacy and safety. Results from the Seven Treatment Evaluation Registry (STER)

Because of the very short half-life of factor VII, prophylaxis in factor VII deficiency is considered a difficult endeavor. The clinical efficacy and safety of prophylactic regimens, and indications for their use, were evaluated in factor VII-deficient patients in the Seven Treatment Evaluation Registry. Prophylaxis data (38 courses) were analyzed from 34 patients with severe factor VII deficiency (<1-45 years of age, 21 female). Severest phenotypes (central nervous system, gastrointestinal, joint bleeding episodes) were highly prevalent. Twenty-one patients received recombinant activated factor VII (24 courses), four received plasma-derived factor VII, and ten received fresh frozen plasma. Prophylactic schedules clustered into "frequent" courses (three times weekly, n=23) and "infrequent" courses (≤ 2 times weekly, n=15). Excluding courses for menorrhagia, "frequent" and "infrequent" courses produced 18/23 (78%) and 5/12 (41%) "excellent" outcomes, respectively; relative risk, 1.88; 95% confidence interval, 0.93-3.79; P=0.079. Long term prophylaxis lasted from 1 to >10 years. No thrombosis or new inhibitors occurred. In conclusion, a subset of patients with factor VII deficiency needed prophylaxis because of severe bleeding. Recombinant activated factor VII schedules based on "frequent" administrations (three times weekly) and a 90 μg/kg total weekly dose were effective. These data provide a rationale for long-term, safe prophylaxis in factor VII deficiency.