Five new F10 variants in hereditary factor x deficiency detected by high-throughput sequencing

INTRODUCTION

Factor X deficiency is a rare inherited bleeding disorder. To date, 181 variants are reported in the recently updated F10-gene variant database.

AIM

This study aimed to describe new F10 variants.

METHOD

The F10 gene was analysed in 16 consecutive families with FX deficiency by a targeted high-throughput sequencing approach, including F10, F9, F8 genes, and 78 genes dedicated to haematological malignancies.

RESULTS

We identified 19 variants (17 missense, one nonsense and one frameshift) and two copy number variations. Two patients presenting a combined FVII-FX deficiency showed a loss of one F10 gene copy (del13q34) associated with a missense variant on the remaining allele, leading to a FX:C significantly lower than the FVII:C level and explaining their unusual bleeding history. We reported five novel variants. Three missense variants (p.Glu22Val affecting the signal peptide cleavage site, p.Cys342Tyr removing the disulphide bond between the FX heavy and light chains, and p.Val385Met located in FX peptidase S1 domain) were detected at compound heterozygosis status in three patients with severe bleeding symptoms and FX:C level below 10 IU/dL. Two truncating variants p.Tyr279* and p.Thr434Aspfs*13 leading to an altered FX protein were found at heterozygous state in two patients with mild bleeding history.

CONCLUSION

This study showed the feasibility and the interest of high-throughput sequencing approach for rare bleeding disorders, enabling the report of F10 gene screening in a 3-weeks delay, suitable for clinical use. The description of five new variants may contribute to a better understanding of the phenotype-genotype correlation in FX deficiency.

Surgery in rare bleeding disorders: the prospective MARACHI study

Background

Despite the wide use of bleeding scores and the reliability of clotting factor level measurement, bleeding risk stratification before surgery remains challenging in patients with rare inherited bleeding disorders.

Objectives

This multicenter observational prospective study assessed in patients with rare coagulation factor deficiency, the perioperative hemostatic management choices by hemostasis experts and the bleeding outcomes after surgery.

Methods

One hundred seventy-eight patients with low coagulation activity level (factor [F] II, FV, combined FV-FVIII, FVII, FX, or FXI <50%) underwent 207 surgical procedures. The bleeding outcome, Tosetto's bleeding score, and perioperative hemostatic protocols were collected.

Results

Among the 81 procedures performed in patients with severe factor deficiency (level ≤10%), 27 were done without factor replacement (including 6 in patients at high bleeding risk), without any bleeding event. Factor replacement therapy was used mainly for orthopedic procedures. In patients with mild deficiency, 100/126 surgical procedures were carried out without perioperative hemostatic treatment. In patients with FVII or FXI deficiency, factor replacement therapy was in function of the procedure, bleeding risk, and to a lesser extent previous bleeding history. Tranexamic acid was used in almost half of the procedures, particularly in case of surgery in tissues with high fibrinolytic activity (76.8%).

Conclusions

The current perioperative hemostatic management of patients with rare bleeding disorders appears to be adapted. Among the 207 procedures, only 6 were associated with excessive bleeding. Our findings suggest that rather than the bleeding score, factor level and surgery type are the most relevant criteria for perioperative factor replacement therapy.

Determinants of adherence and consequences of the transition from adolescence to adulthood among young people with severe haemophilia (TRANSHEMO): A multicentric French national observational cross-sectional study based on the FranceCoag registry

INTRODUCTION

It is necessary to gain insights into adherence to healthcare in people with severe haemophilia (PwSH), especially during the transition from paediatric to adult care, which is an important phase in lives of young people with childhood chronic disease. This adherence can be considered as a marker of successful transition.

OBJECTIVES

The main objective of the quantitative phase of the TRANSHEMO project was to compare the adherence to healthcare between adolescents and young adults (YAs) with severe haemophilia. The secondary objective was to identify the determinants (facilitators and barriers) of this adherence and associations between these determinants.

METHODS

A multicentre, observational, cross-sectional study was conducted in 2017-2019 on PwSH aged between 14 and 17 years (adolescents) or between 20 and 29 years (YAs), included in the FranceCoag registry and having completed the questionnaires. The adherence to healthcare (treatment regimens and clinical follow-up) was compared between adolescents and YAs using the chi-squared test. The determinants of this adherence were analysed by structural equation modelling.

RESULTS

There were 277 participants, 107 adolescents, and 170 YAs. The rate of adolescents adhering to healthcare was 82.2%, while the rate of YAs was 61.2% (p < .001). The barriers to the adherence to healthcare were being YA, having repeated at least one school grade and presenting mental health concerns.

CONCLUSION

Adolescents had better adherence to healthcare than YAs. According to the determinants enlightened in this project, targeted supportive strategies and adapted therapeutic education programs can be developed for young PwSH to facilitate their adherence to healthcare.

Prostate biopsy and prostate cancer management in patients with haemophilia: The experience of French Haemophilia Treatment Centres

BACKGROUND

Data are limited on prostate cancer (PC) management in patients with haemophilia (PWH).

AIM

To describe PC screening and diagnosis, treatment modalities and bleeding complications in a group of unselected PWH followed at French Haemophilia Treatment Centres (HTCs) PATIENTS AND METHODS: PC screening, management and bleeding complications were retrospectively investigated at 14 French HTCs between 2003 and 2018.

RESULTS

Among> 1549 > 50-year-old PWHs, 73 (4.7%) underwent PC screening (median age 71.1 years; 67/6 HA/HB, 17/56 severe-moderate/mild). At diagnosis, haematuria was infrequent. Prophylaxis was administered during 76/86 (88%) prostate biopsies (PB) (n = 67 clotting factor concentrates, CFC; n = 9 desmopressin; n = 17 associated with tranexamic acid, TA). Bleeding (11/86, 12.8%) occurred mainly post-prophylaxis (median delay: 7 days): haematuria (9/11, 81.8%), and rectal bleeding (2/11, 18.2%) including one major (1.2%). PC was confirmed in 50/86 PB and in two prostatectomy specimens (total n = 50 patients, n = 6 with only active surveillance). Surgery (n = 28/44 patients) was managed with CFC. Fifteen patients had radiotherapy/brachytherapy, 10 had hormone therapy; CFC-based prophylaxis was only prescribed for brachytherapy (n = 2). Major bleedings occurred in 3/28 (10.7%) and 2/15 (13.3%) patients who underwent surgery and radio/brachytherapy, respectively. No bleeding risk factor was found.

CONCLUSION

Our data indicate that PB requires prophylaxis for atleast 7 days, using CFC, desmopressin or TA in function of haemophilia severity. PC surgery should be considered at high bleeding risk. Long-term post-procedural CFC or oral TA could be discussed. Radiotherapy/brachytherapy also should be managed with prophylaxis (CFC or TA).

Long-Term Antithrombotic Treatments Prescribed for Cardiovascular Diseases in Patients with Hemophilia: Results from the French Registry

Cardiovascular diseases (CVDs) are a major issue in aging patients with hemophilia (PWHs). Antithrombotic agents are widely used in the general population for CVD treatment, but this recommendation is not fully applicable to PWHs. To improve treatment strategies, a prospective case-control study (COCHE) that analyzed CVD management and follow-up (2 years/patient) in PWHs was performed in France from 2011 to 2018. In total, 68 PWHs (median age: 65 years [39-89]; 48 mild, 10 moderate, and 10 severe hemophilia) were included (n = 50 with acute coronary syndrome, n = 17 with atrial fibrillation, n = 1 with both). They were matched with 68 control PWHs without antithrombotic treatment. In our series, bleeding was significantly influenced by (1) hemophilia severity, with a mean annualized bleeding ratio significantly higher in COCHE patients than in controls with basal clotting factor level up to 20%, (2) antihemorrhagic regimen (on-demand vs. prophylaxis) in severe (hazard ratio [HR] = 16.69 [95% confidence interval, CI: 8.2-47.26]; p < 0.0001) and moderate hemophilia (HR = 42.43 [95% CI: 1.86-966.1]; p = 0.0028), (3) type of antithrombotic treatment in mild hemophilia, with a significantly higher risk of bleeding in COCHE patients than in controls for dual-pathway therapy (HR = 15.64 [95% CI: 1.57-115.8]; p = 0.019), anticoagulant drugs alone (HR = 9.91 [95% CI: 1.34-73.47]; p = 0.0248), dual antiplatelet therapy (HR = 5.31 [95% CI: 1.23-22.92]; p = 0.0252), and single antiplatelet therapy (HR = 3.76 [95% CI: 1.13-12.55]; p = 0.0313); and (4) HAS-BLED score ≥3 (odds ratio [OR] = 33 [95% CI: 1.43-761.2]; p = 0.0065). Gastrointestinal bleeding was also significantly higher in COCHE patients than in controls (OR = 15 [95% CI: 1.84-268]; p = 0.0141). The COCHE study confirmed that antithrombotic treatments in PWHs are associated with increased bleeding rates in function of hemophilia-specific factors and also of known factors in the general population.

Determinants of adherence and consequences of the transition from adolescence to adulthood among young people with severe haemophilia (TRANSHEMO): study protocol for a multicentric French national observational cross-sectional study

INTRODUCTION

Severe haemophilia is a rare disease characterised by spontaneous bleeding from early childhood, which may lead to various complications, especially in joints. It is nowadays possible to avoid these complications thanks to substitutive therapies for which the issue of adherence is major. The transition from adolescence to adulthood in young people with severe haemophilia is a critical period as it is associated with a high risk of lack of adherence to healthcare, which might have serious consequences on daily activities and on quality of life.

METHODS AND ANALYSIS

We present the protocol for a cross-sectional, observational, multicentric study to assess the differences between adolescents and young adults with severe haemophilia in France through the transition process, especially on adherence to healthcare. This study is based on a mixed methods design, with two complementary and consecutive phases, comparing data from a group of adolescents (aged 14-17 years) with those from a group of young adults (aged 20-29 years). The quantitative phase focuses on the determinants (medical, organisational, sociodemographic and social and psychosocial and behavioural factors) of adherence to healthcare (considered as a marker of the success of transition). The qualitative phase explores participants' views in more depth to explain and refine the results from the quantitative phase. Eligible patients are contacted by the various Haemophilia Treatment Centres participating in the French national registry FranceCoag.

ETHICS AND DISSEMINATION

The study was approved by the French Ethics Committee and by the French National Agency for Medicines and Health Products Safety (number: 2016-A01034-47). Study findings will be disseminated to the scientific and medical community in peer-reviewed journals and presented at scientific meetings. Results will be popularised to be communicated via the French association for people with haemophilia to participants and to the general public.

TRIAL REGISTRATION NUMBER

NCT02866526; Pre-results.

Guided Implant Surgery to Reduce Morbidity in Von Willebrand Disease Patients: A Case Report

Introduction

Von Willebrand Disease is the most common inherited bleeding disorder. In the general population, 1/8000 patients are affected. Primary hemostasis (platelet adhesion) and coagulation (protection of Factor VIII) are altered. Among several bleeding symptoms, these patients suffer from excessive bleeding of oral mucosa and dental management requires a close collaboration between haematologists and oral surgeons.

Materials & Methods

Guided implant surgery can be used to increase the accuracy of implant placement and to reduce the overall morbidity of this surgical procedure by using a flapless surgery technique.

Case Report

We report the case of a 49 years old woman having a Type 2A von Willebrand disease and who presented to replace tooth #.46 because of interradicular fracture and peri-apical infection. After planning the implant surgery using Codiagnostix^® software, a surgical guide was prepared. The patient received 4 injections of von Willebrand factor (Willfactin^®) for this particular surgical procedure. The implant was placed immediately after tooth removal and local haemostasis was performed.

Discussion

The follow-up was uneventful and the implant was restored by a crown 4 months later. Two cases of implant placement in haemophiliac patients have been reported before in the literature.

Conclusion

As far as we know, this is the first case report of implant placement in a patient having a von Willebrand disease. The use of guided surgery allowed to perform a mini-invasive procedure and thus contributed to prevent bleeding complications in this patient.