The rare coagulation disorders - review with guidelines for management from the United Kingdom Haemophilia Centre Doctors' Organisation

The History of Rare Bleeding Disorders

Deficiencies in coagulation factors I (FI), FII, FV, combined FV and FVIII (CF5F8) and vitamin K-dependent coagulation factors FVII, FX, FXI, and FXIII have been referred to as rare bleeding disorders (RBDs), rare coagulation factor deficiencies (RCFDs), or recessively inherited coagulation disorders. Fibrinogen was most likely the first member of this group to be identified, with reports of its discovery spanning from 1859 to 1966. If not, then the first coagulation factor to be identified was prothrombin in 1894, and the last coagulation factor to be found was FX in 1956, about 60 years later. The first patient to be diagnosed with an RBD was a 9-year-old boy with afibrinogenemia in 1920 and the vitamin K-dependent coagulation factors deficiency was the most recent RBD in this group to be identified in a 3-month-old child in 1966. The initial therapeutic option for nearly all patients with RBDs was whole blood transfusion; this was replaced in 1941 by fresh frozen plasma (FFP), and then in later years by cryoprecipitate and coagulation factor concentrates. Fibrinogen concentrate was the first coagulation factor concentrate produced in 1956. Coagulation factor concentrate is now available for FI, FVII, FX, FXI, and FXIII; however, FFP and/or platelet transfusion are the only treatments available for FV deficiency. The only recombinant concentrates available for RBDs are for FVII and FXIII, which date from 1988 and the 2000s, respectively. Even though the clinical presentations, diagnosis, and management of lesser-known bleeding disorders have improved significantly in recent decades, more studies are needed to reveal the hidden aspects of these disorders in order to overcome diagnostic and therapeutic challenges and ultimately improve the quality of life for those who are affected.

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

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

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.

Guideline for diagnosis and management of congenital dysfibrinogenemia

INTRODUCTION

Congenital dysfibrinogenemia (CD) is characterized by dysfunction induced by an abnormal fibrinogen molecule structure that results in blood coagulation dysfunction. The clinical manifestations of CD patients are asymptomatic, bleeding and thrombosis. The majority of patient are asymptomatic. However, the single fibrinogen detection method is easy to cause missed diagnosis or misdiagnosis of CD patients. The treatment strategies of CD patients with different clinical manifestations are also different.

METHODS

Combing the existing experimental diagnosis technology, literature and our research results, a simple and practical CD diagnostic criteria was proposed. And based on the relevant literature and existing treatment guidelines, more comprehensive treatment recommendations are summarized.

RESULTS

In this new criteria, combination Clauss method and PT derived method was proposed to detect fibrinogen and its ratio was used to diagnose for CD. Diagnosis also needs to be combined the clinical manifestations, family investigation and genetic testing. According to different clinical manifestation (bleeding, thrombosis or asymptomatic), treatment methods and strategies are different. The treatment of CD patients should consider the patient's personal and family history of bleeding or thrombosis. Treatment of thrombosis and pregnancy may be more challenging. The risk of bleeding and thrombosis should be evaluated and balanced at all times during clinical treatment. These detailed treatment recommendations can provide reference for patients with different clinical manifestations of CD.

CONCLUSIONS

The new CD diagnosis criteria and comprehensive treatment recommendations can effectively improve the diagnosis and treatment of CD.

Factor X deficiency and pregnancy

Factor X (FX) is a vitamin K-dependent enzyme, which acts as an important coagulation factor of coagulation cascade. FX deficiency is an autosomal recessive inherited disease and is often demonstrated in families with consanguity. Pregnancy in women with congenital FX deficiency has been associated with adverse fetal outcomes. We report a case of pregnancy in women with FX deficiency. The patient needed an immediate caesarean section at 38 weeks of gestation because of severe oligohydramnios and fetal distress. FX deficiency during pregnancy was effectively managed, leading to a positive outcome through the optimal utilisation of available resources.

Prolonged coagulation times in severe fever with thrombocytopenia syndrome virus infection, the indicators of heparin-like effect and increased haemorrhagic risk

Prolonged coagulation times, such as activated partial thromboplastin time (APTT) and thrombin time (TT), are common in patients infected with severe fever with thrombocytopenia syndrome virus (SFTSV) and have been confirmed to be related to patient's poor outcome by previous studies. To find out the reason for prolonged coagulation time in patients with SFTSV infection, and whether it predicts haemorrhagic risk or not. Seventy-eight consecutive patients with confirmed SFTSV infection were enrolled in this prospective, single-centre, observational study. Several global and specific coagulation parameters of these patients on admission were detected, and the haemorrhagic events during hospitalization and their outcomes were recorded. Most of the enrolled patients had prolonged APTT (82.1%) and TT (80.8%), normal prothrombin time (83.3%) and intrinsic coagulation factors above haemostatic levels (97.4%). The heparin-like effect was confirmed by a protamine neutralization test and anti-Xa activity detection in most patients. Interestingly, the APTT and TT results were significantly positively correlated with the levels of endothelial markers and viral load, respectively. The APTT was independently associated with the haemorrhage of patients. The prolonged APTT and TT of SFTS patients may mainly be attributed to endogenous heparinoids and are associated with increased haemorrhagic risk.

Rare inherited coagulation disorders: no longer orphan and neglected

Rare inherited coagulation disorders due to the deficiency or dysfunction of coagulation factors have until recently received less clinical attention than hemophilias and von Willebrand disease. This situation has changed in the last decades, mainly due to therapeutic progress with the availability of more and safer products for replacement therapy produced by plasma fractionation or recombinant DNA technology. This narrative review, based on the latest literature and expert opinion, emphasizes the progress achieved for each of the rare deficiencies, mentions the still unmet therapeutic needs, and sketches the perspectives for further progress.

Partial Splenic Embolization in a Patient with Hemophilia A and Severe Thrombocytopenia: A Case Report

We report a patient with hemophilia A who underwent partial splenic embolization (PSE) for severe thrombocytopenia secondary to portal hypertension-induced splenomegaly, resulting in a stable long-term quality of life. The patient was diagnosed with hemophilia A and unfortunately contracted human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) from blood products. He subsequently developed progressive splenomegaly due to portal hypertension from chronic HCV, resulting in severe thrombocytopenia. PSE was performed because he had occasional subcutaneous bleeding and needed to start interferon (IFN) and ribavirin (RBV) treatment for curing his HCV infection at that time. His platelet counts increased, and no serious adverse events were observed. Currently, he continues to receive outpatient treatment, regular factor VIII (FVIII) replacement therapy for hemophilia A, and antiretroviral therapy for HIV infection. Vascular embolization has been reported to be an effective and minimally invasive treatment for bleeding in hemophilia patients. PSE also provided him with a stable quality of life without the side effects of serious infections and thrombocytopenia relapses. We conclude that PSE is a promising therapeutic option for patients with hemophilia A.

Rare bleeding disorders: Real-world data from a Spanish tertiary hospital

INTRODUCTION

Due to their low prevalence, rare bleeding disorders (RBDs) remain poorly characterized.

AIM

To gain insight of RBDs through our clinical practice.

METHODS

Retrospective study of the medical records of RBD patients followed up at the Central University Hospital of Asturias between January 2019 and December 2022.

RESULTS

A total of 149 patients were included. Factor (F) VII (44 %) and FXI (40 %) deficiencies were the most common diagnosed coagulopathies. Most of the patients were asymptomatic (60.4 %) and the most frequent type of bleeding were mucocutaneous and after surgery. All replacement treatments were administered on demand and no patient was on a prophylaxis regimen. Currently available products were safe; allergic reactions after administration of plasma were the most frequent complication. Genetic analysis, carried out on 55 patients (37 %), showed that the most frequent mutations in RBDs are of missense type (71.9 %). We identified 11 different novel genetic alterations in affected genes. The c.802C > T (p.Arg268Cys) variant, previously described, was identified in 71 % (15 of 21) of the patients with FXI deficiency genotyped and none were related (probable founder effect).

CONCLUSION

Our study on an unusual large single center cohort of RBD patients portrays location-dependent distinct genetic drives and clinical practice particularities.

Congenital Afibrinogenemia With Facial Haematoma

Congenital afibrinogenemia is a rare inherited blood disorder characterized by a deficiency of fibrinogen, leading to abnormal blood clotting. It is caused by mutations in fibrinogen genes and results in a propensity for bleeding. We present the case of a one-year-old male child with congenital afibrinogenemia who developed a left-sided facial haematoma following a fall from a walker. The child had a history of active bleeding during cannulation and had not undergone circumcision due to the risk of bleeding. This case highlights the need for timely diagnosis and appropriate management of rare bleeding disorders such as congenital afibrinogenemia. Collaboration between different specialties, including haematology and genetic counseling, is crucial for comprehensive care. The rarity of the condition underscores the importance of raising awareness among healthcare professionals. Genetic counseling and family studies are essential for assessing genetic implications and guiding decision-making. Further advancements in diagnostic tests and replacement therapy are needed to improve the management of patients with afibrinogenemia, particularly in regions with a high prevalence of consanguineous marriages.

Plasma-derived human factor X concentrate for the treatment of patients with hereditary factor X deficiency

INTRODUCTION

Hereditary factor X (FX) deficiency (HFXD) is an autosomal recessive rare bleeding disorder that leads to defects in the FX protein. Depending on the degree of deficiency, patients may be at risk of life-threatening bleeding episodes. Historical treatments for FX deficiency include prothrombin complex concentrates, which can increase the risk of thrombosis, and fresh frozen plasma, which can cause volume overload and transfusion reactions. Plasma-derived FX (pdFX), a single-factor, high-purity, high-potency human FX treatment, was approved in 2015 in the United States and in 2016 in Europe for on-demand treatment and prophylaxis of bleeding episodes and perioperative management of patients with HFXD.

METHODS

Five studies that examined the use of pdFX in patients with mild (plasma FX activity [FX:C] ≥5 IU/dL), moderate (FX:C ≥1 and <5 IU/dL), or severe (FX:C < 1 IU/dL) HFXD were reviewed: TEN01, TEN02 and TEN03 were prospective, open-label, multicentre, nonrandomised studies, and TEN05 and TEN06 were multicentre retrospective studies.

RESULTS

When used as an on-demand treatment, pdFX was judged by investigators to be successful in treating 41/42 (97.6%), 2/3 (66.6%) and 79/79 (100%) bleeds in TEN01, TEN02 and TEN05, respectively. When used prophylactically, pdFX was judged 'excellent' for the prevention of bleeds in nine (100%) and eight (100%) patients in TEN02 and TEN05, respectively. Perioperative treatment and pharmacokinetics were also assessed. pdFX was safe and well tolerated.

CONCLUSIONS

Together, these studies support the use of pdFX for on-demand treatment of bleeding, routine prophylaxis, and perioperative management of bleeding in patients with HFXD.

Association between Blood Group and Change in Coagulation Factors in Plasma Preparations for Transfusion Purpose at Kisii Teaching and Referral Hospital

Background

Blood component therapy helps in managing patients with reduced hematopoiesis, elevated peripheral destruction of cells, and generalized blood loss (bleeding). Increased prevalence of arterial and venous thrombotic disease linked to the impact of ABO blood group on plasma levels of coagulation glycoprotein is demonstrated by blood group non-O persons.

Objective

This study had a main objective of determining the association between blood group and change in coagulation factors in plasma preparation for transfusion purpose.

Methods

The study employed a longitudinal study design. Factor assay evaluation was done by the use of Erba Mannheim ECL 105 semiautomated coagulation analyzer from India. Thawing meant for consequent coagulation factor analysis and sequential testing of stored cryoprecipitate and fresh frozen plasma was performed by the use of Stericox plasma thawing bath before being analyzed by the coagulation analyzer. Blood group of the collected blood sample in purple EDTA vacutainer was analyzed using blood antisera and a clean white tile, and results were recorded which helped in establishing the association existing between plasma and blood group. The data were fed into Excel and were evaluated by the use of SPSS version 25.

Results

There was no significant association between coagulation factors in fresh frozen plasma and blood group, coagulation factors in cryoprecipitate plasma and blood group of the donors showed that the relationship was not significant with, (r = -0.116, -0.097, 0.007 and 0.047 with p value (0.900, 0.087, 0.096 and 0.096), respectively, which are greater than 0.005 standard alpha value.

Conclusion

This study has shown no significant association existing between blood group and change in coagulation factors in plasma preparations at Kisii Teaching and Referral Hospital.

Maternal Coagulation Disorders and Postpartum Hemorrhage

Coagulation disorders are rare causes of postpartum hemorrhage. Disturbances in coagulation should be suspected in patients with a family history of coagulopathy, those with a personal history of heavy menstrual bleeding, and those with persistent bleeding despite correction of other causes. The coagulopathic conditions discussed include disseminated intravascular coagulation, platelet disorders, and disturbances of coagulation factors. These should not be overlooked in the evaluation of obstetric hemorrhage, as diagnosis and appropriate treatment may prevent severe maternal morbidity and mortality.

Blood Product Replacement for Postpartum Hemorrhage

Consideration for blood products replacement in postpartum hemorrhage should be given when blood loss exceeds 1.5 L or when an estimated 25% of blood has been lost. In cases of massive hemorrhage, standardized transfusion protocols have been shown to improve maternal morbidity and mortality. Most protocols recommend a balanced transfusion involving a 1:1:1 ratio of packed red blood cells, platelets, and fresh frozen plasma. Alternatives such as cryoprecipitate, fibrinogen concentrate, and prothrombin complex concentrates can be used in select clinical situations. Although transfusion of blood products can be lifesaving, it does have associated risks.

How to assess parallelism in factor assays: coefficient of variation of results with different dilutions or slope ratio?

INTRODUCTION

Non-parallelism in factor assays can lead to incorrect factor activities. Parallelism can be assessed by calculating the coefficient of variation (CV) of results obtained on 3 dilutions of the same sample. Some authors have proposed that if there is <15% then the average activity is reportable. Some analysers use a slope ratio (SR) to calculate parallelism, with an acceptance range of approximately 0.9-1.1.

METHODS

We evaluated CV and SR in one stage FII-FXII assays on Sysmex CS5100i using Innovin or Actin FS. Frozen normal and pathological plasmas, plasmas containing Direct Oral Anticoagulants, Direct Thrombin Inhibitors or Lupus Anticoagulant were analysed to assess possible non-parallelism.

RESULTS

In plasmas with factor levels >25 IU/dl (plus no interfering substances) all CVs were < 15%. One sample (low factor activities 10-15 IU/dl), had CVs > 15% in FII, FVII and FXII assays only. SR outside of 0.9-1.1 were seen in FII and FXII assays at different levels of clotting factor including some within the normal range. Non-parallelism was detected more frequently with SR than CV for those with interfering substances.

CONCLUSIONS

SR outside of 0.9-1.1 were seen in different levels of clotting factors, including samples which did not contain interfering substances. The target of 15% CV was a better discriminator than a SR for acceptance. When factor levels were reduced to around 10-15 IU/dl, a target 20 %CV was more appropriate than 15%. It might be appropriate for laboratories to assess locally whether their acceptance criteria need to be wider at low levels of clotting factors.

Building the foundation for a community-generated national research blueprint for inherited bleeding disorders: research priorities for ultra-rare inherited bleeding disorders

BACKGROUND

Ultra-rare inherited bleeding disorders (BDs) present important challenges for generating a strong evidence foundation for optimal diagnosis and management. Without disorder-appropriate treatment, affected individuals potentially face life-threatening bleeding, delayed diagnosis, suboptimal management of invasive procedures, psychosocial distress, pain, and decreased quality-of-life.

RESEARCH DESIGN AND METHODS

The National Hemophilia Foundation (NHF) and the American Thrombosis and Hemostasis Network identified the priorities of people with inherited BDs and their caregivers, through extensive inclusive community consultations, to inform a blueprint for future decades of research. Multidisciplinary expert Working Group (WG) 3 distilled highly feasible transformative ultra-rare inherited BD research opportunities from the community-identified priorities.

RESULTS

WG3 identified three focus areas with the potential to advance the needs of all people with ultra-rare inherited BDs and scored the feasibility, impact, and risk of priority initiatives, including 13 in systems biology and mechanistic science; 2 in clinical research, data collection, and research infrastructure; and 5 in the regulatory process for novel therapeutics and required data collection.

CONCLUSIONS

Centralization and expansion of expertise and resources, flexible innovative research and regulatory approaches, and inclusion of all people with ultra-rare inherited BDs and their health care professionals will be essential to capitalize on the opportunities outlined herein.

Pharmacokinetics, efficacy and safety of a novel fibrinogen concentrate in pediatric patients with congenital afibrinogenemia

INTRODUCTION

Congenital afibrinogenemia treatment with plasma-derived fibrinogen concentrates in pediatric patients is limited. This study investigated the pharmacokinetics, surrogate efficacy, and safety of a plasma-derived fibrinogen concentrate (FIB Grifols) in pediatric patients with congenital afibrinogenemia.

METHODS

Patients aged <18 years old diagnosed with congenital afibrinogenemia were included in this prospective, multinational, phase 1-2, single-arm study. After a single dose of a plasma-derived fibrinogen concentrate (70 mg/kg body weight), pharmacokinetic parameters were determined from plasma fibrinogen activity (Clauss method) and antigen method (ELISA), and calculated by noncompartmental and population pharmacokinetic (popPK) models. Patients were followed up over 14 days. Efficacy variables were the mean change on thromboelastographic variables (maximum clot firmness [MCF], alpha angle [ α ]) and coagulation tests (prothrombin time, activated partial thromboplastin time, and thrombin time) 1 h postinfusion. Safety parameters were assessed.

RESULTS

Eleven patients with a median (range) age 8.80 (3.7-12.7) years were treated with the plasma-derived fibrinogen concentrate. Using the popPK modeling, fibrinogen activity reached a mean (standard deviation) Cmax of 1.3 (0.225) g/l, half-life ( t1/2 ) of 60.6 (4.48) h and incremental in vivo recovery (IVR) of 1.86 (0.322) (mg/dl)/(mg/kg). Surrogate efficacy was demonstrated by significant increase in MCF (9.23 [3.94] mm; P  < 0.001; 95% confidence interval 6.58, 11.87). All coagulation times were significantly shortened after fibrinogen concentrate infusion. Adverse events were mild or moderate in severity, and unrelated to fibrinogen concentrate.

CONCLUSIONS

In pediatric patients with congenital afibrinogenemia, plasma-derived fibrinogen concentrate revealed a favorable and specific pharmacokinetic profile, demonstrated efficacy in coagulation and was safe and well tolerated.

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.

A low-dose therapy of fibrinogen supplement during perioperative period of total knee arthroplasty in an asymptomatic man with congenital dysfibrinogenemia: A case report

RATIONALE

Congenital dysfibrinogenemia (CD) is a rare coagulation system disease that is often treated without unified management. Individualized treatment thereof presents clinicians with great challenges.

PATIENT CONCERNS

A patient who was about to undergo total knee arthroplasty was found to have CD.

DIAGNOSES

Coagulation screening revealed low fibrinogen, prolonged thrombin time, minor prolonged prothrombin time, and normal activated partial thromboplastin time were detected during admission, but no abnormal personal and family history findings were observed. Therefore, CD and hypofibrinogenemia were suspected. The gene sequencing confirmed the diagnosis of CD.

INTERVENTIONS

The patient received plenty and low level of fibrinogen concentrate during 2 perioperative periods, respectively.

OUTCOMES

Successful clinical outcomes were obtained using different treatment strategies.

LESSONS

In contrast to prior case reports, this case illustrates the feasibility of low dosing of fibrinogen supplements within an asymptomatic patient in a selective operation. Changes in the level of fibrinogen and fibrin degradation product are of great importance for individualized treatment after supplementation.

Planning Pregnancy and Birth in Women with Inherited Bleeding Disorders

Inherited bleeding disorders are characterized by a diverse clinical phenotype within and across specific diagnoses. von Willebrand disease (VWD), hemophilia A, and hemophilia B comprise 95 to 97% of inherited bleeding disorders, with the remaining 3 to 5% attributed to rare bleeding disorders, including congenital fibrinogen disorders, factor deficiencies (affecting FII, FV, FV + FVIII, FVII, FX, FXI, and FXIII), and platelet function defects. The pregnancy, birth, and the puerperium may be adversely influenced in the setting of an inherited bleeding disorder depending on its type and clinical phenotype. Obstetric hemostatic challenges may sometimes also unmask the presence of a previously unknown inherited bleeding disorder. This review aims to address the approach to pregnancy and birth in the context of an inherited bleeding disorder and highlights the significance of multidisciplinary input into the care of these women.

Combined Liver-Kidney Transplant for Juvenile Polycystic Kidney Disease and Concomitant Hereditary Factor V Deficiency

Factor V deficiency is a congenital bleeding diathesis that, in selected cases, may be managed with liver transplant. In this case, we describe the treatment of an adult patient with kidney failure secondary to juvenile onset polycystic kidney disease who received a combined liver-kidney transplant as a method to manage the risks associated with the need for a kidney transplantin the setting of factorV deficiency and high sensitization.

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.

Gynaecological management of women with inherited bleeding disorders

Women with inherited bleeding disorders (IBDs) may present to healthcare professionals in a variety of ways and commonly will be encountered by either haematology or gynaecology services. Heavy menstrual bleeding is very often the first manifestation of an IBD. There is a wide variation in severity of bleeding for women with IBD and diagnosis and subsequent management of their condition requires multidisciplinary specialised care which is tailored to the individual and includes excellent cross-specialty communication between gynaecology and haematology teams. This guideline is intended for both haematologists and gynaecologists who are involved in the diagnosis and management of women with bleeding disorders. It sets out recommendations about how to investigate heavy menstrual bleeding (HMB), the commonest presentation for women with IBD to hospital services, to guide physicians about how to diagnose an IBD and covers the management of women with known IBD and HMB. The second section sets out recommendations for patients known to have IBD and covers management of patients with IBD in the setting of gynaecological surgery and management for all other non-surgical gynaecological situations.

A review of the pharmacokinetics, efficacy and safety of high‐purity factor X for the prophylactic treatment of hereditary factor X deficiency

Introduction

Hereditary factor X (FX) deficiency (FXD) is a rare autosomal recessive bleeding disorder. Plasma‐derived FX (pdFX) is a high‐purity FX concentrate approved in the United States and Europe for the treatment and prophylaxis of bleeding episodes and for peri‐operative management in patients with hereditary FXD (HFXD).

Aim

To review pharmacokinetic dosing, efficacy, and safety data for pdFX as routine prophylaxis for HFXD.

Methods

Summary of the published pharmacokinetic and safety data from TEN01, TEN02, TEN05, and real‐world publications of pdFX for prophylaxis.

Results

Pharmacokinetic modelling data from the phase 3 TEN01 study supported administration of pdFX 25 IU/kg twice weekly for routine prophylaxis in adolescents/adults (aged ≥12 years). Results from nine paediatric patients in the phase 3 TEN02 study and eight adolescents/adults (aged ≥12 years) in the retrospective data‐collection TEN05 study, along with real‐world evidence, showed that routine prophylaxis with pdFX ≈40 IU/kg twice weekly in patients aged <12 years and pdFX ≈25 IU/kg twice weekly in patients aged ≥12 years was effective in bleeding prevention.

Conclusions

pdFX was well tolerated in clinical studies, with no new safety signals identified during routine prophylactic use. Based on current evidence, it is recommended that routine prophylaxis with pdFX be initiated at 25 IU/kg twice weekly in adults/adolescents ≥12 years of age, and at a dosage of 40 IU/kg twice weekly in children <12 years of age. Thereafter, FX levels should be closely monitored, and dosages should be adjusted according to clinical response and to maintain trough levels ≥5 IU/dl.

Successful treatment of intractable pseudomeningocele with FXIII deficiency by surgery and FXIII replacement therapy: A case report

Pseudomeningocele is an extradural cystic collection of cerebrospinal fluid (CSF) and is rare and typically asymptomatic. However, pseudomeningocele is sometimes associated with symptoms. Whether symptomatic pseudomeningocele is best treated conservatively or surgically remains controversial. Factor XIII (FXIII) is a blood coagulation factor that also promotes fibroblast proliferation during wound healing. Although treatment of postsurgical CSF leakage with FXIII has been reported, there have been no reports on surgical treatment and FXIII replacement therapy of pseudomeningocele with FXIII deficiency. We report a case of pseudomeningocele with FXIII deficiency that was successfully treated by surgery and FXIII replacement therapy. The patient presented with symptoms of intracranial hypotension syndrome that had started a few months after laminectomy for thoracic ossification of the ligamentum flavum 2 years earlier. Magnetic resonance imaging and delayed computed tomography myelography confirmed a diagnosis of pseudomeningocele. Epidural blood patch treatment was performed twice but did not result in improvement. Furthermore, the FXIII level decreased to 56%, so the patient was also diagnosed as having acquired FXIII deficiency. We elected to treat the patient by surgery with FXIII replacement therapy. The dural injury was repaired using an artificial dura mater patch, fibrin glue, and polyglycolic acid sheets. The FXIII level was 74%–135% during the perioperative period. The patient had a good postoperative course. Postoperative magnetic resonance images showed resolution of the pseudomeningocele. There was no recurrence during 6 months of follow-up. Perioperative FXIII replacement may be a useful treatment for pseudomeningocele with FXIII deficiency.

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Pseudomeningocele is an extradural cystic collection of cerebrospinal fluid.

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Whether symptomatic pseudomeningocele is best treated remains controversial.

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Factor XIII is a blood coagulation factor that also promotes fibroblast proliferation.

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There have been no reports on surgical treatment and FXIII replacement therapy of pseudomeningocele with FXIII deficiency.

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We report a case of pseudomeningocele treated by surgery and FXIII replacement therapy.

Report of surgeries, their outcome and the thrombin generation assay in patients with Factor XI deficiency: A retrospective single-centre study

BACKGROUND

In patients with FXI deficiency, the risk of surgery-related bleeding is poorly correlated with plasma FXI activity (FXI:C); the latter can therefore not be used as a reliable predictor of bleeding in surgeries.

OBJECTIVES

The aim of this retrospective study was to determine whether thrombin generation assay (TGA) could be used to evaluate the risk of surgery-related bleeding in FXI-deficient patients. TGA parameters were compared to FXI:C values, haemostatic treatments and surgical outcomes.

PATIENTS

All patients followed at the haemophilia treatment care centre (Lyon, France) with a FXI:C < 50IU/dL, and for whom a baseline TGA was performed between January 2014 and December 2019, were included.

RESULTS

Among the 175 surgeries reported herein in 49 patients, FXI concentrates were used for 11 (6%) surgeries and fresh frozen plasma was used for five (3%) surgeries; these surgeries were performed in patients with two or three impaired TGA parameters. No haemostatic treatment was prescribed for 119 (68%) surgeries. A surgery-related bleeding occurred in 12 patients during 21 (12%) surgeries. Thrombin generation was significantly reduced or delayed in patients who reported surgery related-bleeding. Among the 34 (68%) surgeries performed without haemostatic treatment in patients with three impaired TGA parameters, a surgery-related bleeding was reported in 44% of cases (15 surgeries out of 34).

CONCLUSION

The present study confirmed that TGA is an interesting laboratory test in FXI deficiency, for determining the bleeding risk and guiding the haemostatic management of surgeries, while taking into account the surgical bleeding risk and the history of bleeding.

Safety and effectiveness of recombinant factor XIII-A2 in congenital factor XIII deficiency: Real-world evidence

BACKGROUND

Regular factor XIII (FXIII) prophylaxis is standard treatment for congenital FXIII A-subunit deficiency (FXIII-A CD). Recombinant factor XIII-A2 (rFXIII-A2) was extensively evaluated in the mentor trials.

OBJECTIVE

To assess real-world safety and treatment effectiveness of rFXIII-A2 prophylaxis from the mentor 6 trial.

PATIENTS/METHODS

mentor 6 was a noninterventional, postauthorization safety study investigating rFXIII-A2 prophylaxis in FXIII-A CD. rFXIII-A2 treatment was observed for 2 to 6 years per patient. The primary end point was documentation of adverse drug reactions (including anti-FXIII antibody development). Secondary end points were serious adverse events (SAEs), medical events of special interest (MESIs), and annualized bleeding rate (ABR).

RESULTS

Among 30 patients (mean age, 25.5 years), there were 44 adverse events (AEs) (30 mild, 13 moderate, 1 severe). Eleven AEs were possibly/probably related to rFXIII-A2. Of four MESIs, two were unlikely related to rFXIII-A2 (accidental overdose, deep vein thrombosis), and two were possibly/probably related (nonneutralizing anti-FXIII antibody, decreased therapeutic response). All 10 SAEs were unlikely related to rFXIII-A2. Over a follow-up of 75.4 patient-years, there were six treatment-requiring bleeds (all trauma-related with no spontaneous bleeds), giving a treatment-requiring ABR of 0.066; five bleeds were treated successfully with rFXIII-A2. Eight of nine minor surgeries performed during rFXIII-A2 prophylaxis reported successful hemostatic outcomes (one missing evaluation).

CONCLUSIONS

These data confirm that rFXIII-A2 prophylaxis is well tolerated as long-term care. There were no spontaneous bleeds, ABR was low, and rFXIII-A2 successfully treated bleeds in patients receiving rFXIII-A2 prophylaxis.

Factor XIII and surgical bleeding. A narrative review

FXIII is the final factor in the coagulation cascade. It converts soluble fibrin monomers into a stable fibrin clot, prevents premature degradation of fibrin, participates in wound healing, and helps prevent the loss of the endothelial barrier function. FXIII deficiency is believed to be rare, and this may explain why clinicians do not routinely take it into consideration. Congenital FXIII deficiency is a rare disease with a reported prevalence of 1 per million. However, the prevalence of acquired FXIII deficiency is much higher. Acquired forms have been described in patients with decreased hepatic or bone marrow synthesis, hyperconsumption and increased degradation by autoantibodies. This review offers guidance on how to suspect and diagnose FXIII deficiency in both the preoperative consultation and different surgical settings. We also analyze current scientific evidence in order to clarify when and why this clinical situation should be suspected, and how it may be treated.

Factor XI deficiency: About 20 cases and literature review

INTRODUCTION

Factor XI deficiency is a rare coagulation disorder with variable bleeding manifestations.

AIM

To evaluate the correlation between the degree of factorXI deficiency and the clinical expression of the disease.

METHODS

Retrospective study, spanning 10 years from January 1, 2010 to December 31, 2019, concerning patients followed at the Hemophilia Center at Aziza Othmana Hospital in Tunis. The data were collected from the medical records. The determination of PT, APTT, fibrinogen level and coagulation factors are performed by coagulometric technique on STA® compact / ACL TOP®. FactorXI deficiency was confirmed on two different samples. Statistical analysis of the clinical-biological correlation was performed using the chi-square test. The significance level was 0.05.

RESULTS

Twenty patients were collected. The mean age of discovery was 25 years with a sex ratio (M/F) =0.33. The circumstances of discovery were incidental in 14 patients. A family history of bleeding was reported in 30% of cases. Eight patients underwent surgery, six of whom had a simple postoperative course. The APTT was prolonged and isolated in 75% of cases. The hemostasis test was normal in 5 cases. The average FactorXI level was 24%. The tendency to bleed did not seem to be correlated with FactorXI levels.

CONCLUSION

Prospective multicenter studies including molecular study would be necessary to better elucidate this rare disorder.

Gastrointestinal bleeding after endoscopic mucosal resection in a case of Peutz-Jeghers syndrome with hypofibrinogenemia: A case report

BACKGROUD

Peutz-Jegers syndrome (PJS) is an autosomal dominant hereditary disorder characterized by hamartomatous polyposis of the entire gastrointestinal tract. Fibrinogen (Fbg) is synthesized by the liver, and hypofibrinogenemia is often asymptomatic and manifests with bleeding after trauma or invasive surgical procedures. Here, we present a case of a pediatric patient with PJS and hypofibrinogenemia who manifested with gastrointestinal bleeding after endoscopic mucosal resection (EMR) of small intestinal polyps.

CASE PRESENTATION

An 11-year-old boy with PJS was referred to our hospital. Since his mother was diagnosed with PJS, with black pigments being observed on his lips, mouth, and limbs, he underwent upper and lower gastrointestinal endoscopy at the age of 8 years at a previous hospital. EMR for duodenal polyp was performed, and the pathological findings were consistent with hamartoma. His Fbg level was 117 mg/dl at the time, with no post-bleeding being detected after EMR. The small intestine was not assessed at the prior facility and was left neglected for three years. At our hospital, small intestine fluoroscopy was performed and revealed a polyp in the jejunum, and abdominal computed tomography showed two polyps and intussusception. On double-balloon enteroscopy, the resected polyps were hamartoma with diameters of 20 and 30 mm. The patient's Fbg level was 107 mg/dl. The day after EMR, he had melena and black stools. He was diagnosed with post-EMR bleeding and started to stop eating, and hemostatic agents were given. His hemoglobin level dropped to 9.2 g/dl the next day. Genetic testing for congenital Fbg deficiency revealed a heterozygous pathogenic variant in fibrinogen gamma chain Exon 10. Therefore, he was diagnosed with concurrent hypofibrinogenemia and PJS.

CONCLUSION

To the best of our knowledge, this is the first reported case with concurrent PJS and hypofibrinogenemia. In patients with PJS, hypofibrinogenemia should be considered as one of the risk factors of postoperative bleeding during polypectomy, and appropriate prophylactic measures should be taken.

[Congenital factor X deficiency: a retrospective analysis of 11 cases]

Objective: To analyze the clinical characteristics, laboratory examination, diagnosis, treatment, and outcome of hereditary factor Ⅹ (FⅩ) deficiency. Methods: Clinical data of 11 patients with congenital FⅩ deficiency were retrospectively analyzed from July 2009 to February 2021. Results: There were 3 males and 8 females. Median age was 39 (5-55) years. The media duration of follow-up was 81.67 (1.87-142.73) months. Of the 11 patients, 10 had bleeding symptoms, 7 had ecchymosis or hemorrhage after skin bump, 7 had nosebleed, 6 had gingival hemorrhage, and 1 had muscle hematoma. Among the female patients, 6 had menorrhagia and 1 experienced bleeding after vaginal delivery. Family history of FⅩ deficiency was found in one case. Eight patients had a history of surgery, and four had postoperative bleeding. Laboratory findings were characterized by significantly prolonged activated partial thromboplastin time, prothrombin time, and decreased FⅩ activity (FⅩ∶C) . Four cases underwent gene mutation analysis and five new mutations were found. Four cases were treated with prothrombin complex concentrates (PCC) and seven cases with fresh frozen plasma (FFP) . One female patient had significantly reduced menstrual volume after PCC prophylactic therapy. One patient received FFP for prophylactic infusion with no bleeding during and after the operation. Conclusion: Most patients with congenital FⅩ deficiency had bleeding symptoms and there was no significant correlation between severity of bleeding symptoms and FⅩ∶C. Prophylaxis should be applied in patients with severe bleeding tendencies. Gene mutation test is significant for screening, diagnosis, and prognosis prediction of congenital FX deficiency.

The lived experience of women with a bleeding disorder: A systematic review

BACKGROUND

Research studies have described the morbidity associated with inherited bleeding disorders such as hemophilia and von Willebrand disease in women, but their effect on daily living has long been underrecognized. This systematic review sought to document the lived experience of women with a bleeding disorder by assessing research findings on quality of health care, socioeconomic factors, and mental health.

METHODS

A systematic search was carried out in Web of Science, the Cumulative Index to Nursing and Allied Health Literature, and PubMed on July 31, 2020. References were hand searched. Abstracts of the 2019 and 2020 congresses on bleeding disorders were hand searched. Key journals were screened for relevant studies published after the search date until the analysis was completed on December 7, 2020.

RESULTS

Of 635 potentially eligible publications, 27 published since 1998 were selected for review. Most studies were of moderate to high quality but meta-analysis of quantitative studies was not possible due to difference in outcomes and assessment.Women with a bleeding disorder experience obstacles to accessing care, difficulties living with their disorder, interference with schooling and work, and poor mental health. Diagnostic delay and lack of recognition of symptoms mean treatment and support may not be available. Where comparisons with controls were made, women's negative experiences were greater than those of men.

CONCLUSIONS

Women with bleeding disorders experience major negative impacts of their disorders on daily life and mental well-being. Many of the challenges identified in earlier research are evident in more recent studies.

Maternal and foetal outcomes following natural vaginal versus caesarean section (c-section) delivery in women with bleeding disorders and carriers

BACKGROUND

Bleeding disorders are uncommon but may pose significant bleeding complications during pregnancy, labour and following delivery for both the woman and the foetus. While many bleeding disorders in women tend to improve in pregnancy, thus decreasing the haemorrhagic risk to the mother at the time of delivery, some do not correct or return quite quickly to their pre-pregnancy levels in the postpartum period. Therefore, specific measures to prevent maternal bleeding and foetal complications during childbirth, are required. The safest method of delivery to reduce morbidity and mortality in these women is controversial. This is an update of a previously published review.

OBJECTIVES

To assess the optimal mode of delivery in women with, or carriers of, bleeding disorders.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Coagulopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched the Cochrane Pregnancy and Childbirth Group's Trials Register as well as trials registries and the reference lists of relevant articles and reviews. Date of last search of the Group's Trials Registers: 21 June 2021.

SELECTION CRITERIA

Randomised controlled trials and quasi-randomised controlled clinical trials investigating the optimal mode of delivery in women with, or carriers of, any type of bleeding disorder during pregnancy were eligible for the review.

DATA COLLECTION AND ANALYSIS

No trials matching the selection criteria were eligible for inclusion.

MAIN RESULTS

No trials matching the selection criteria were eligible for inclusion.

AUTHORS' CONCLUSIONS

The review did not identify any randomised controlled trials investigating the safest mode of delivery and associated maternal and foetal complications during delivery in women with, or carriers of, a bleeding disorder. In the absence of high quality evidence, clinicians need to use their clinical judgement and lower level evidence (e.g. from observational trials, case studies) to decide upon the optimal mode of delivery to ensure the safety of both mother and foetus. Given the ethical considerations, the rarity of the disorders and the low incidence of both maternal and foetal complications, future randomised controlled trials to find the optimal mode of delivery in this population are unlikely to be carried out. Other high quality controlled studies (such as risk allocation designs, sequential design, and parallel cohort design) are needed to investigate the risks and benefits of natural vaginal and caesarean section in this population or extrapolation from other clinical conditions that incur a haemorrhagic risk to the baby, such as platelet alloimmunisation.

Congenital Afibrinogenemia and Hypofibrinogenemia: Laboratory and Genetic Testing in Rare Bleeding Disorders with Life-Threatening Clinical Manifestations and Challenging Management

Congenital fibrinogen disorders are rare pathologies of the hemostasis, comprising quantitative (afibrinogenemia, hypofibrinogenemia) and qualitative (dysfibrinogenemia and hypodysfibrinogenemia) disorders. The clinical phenotype is highly heterogeneous, being associated with bleeding, thrombosis, or absence of symptoms. Afibrinogenemia and hypofibrinogenemia are the consequence of mutations in the homozygous, heterozygous, or compound heterozygous state in one of three genes encoding the fibrinogen chains, which can affect the synthesis, assembly, intracellular processing, stability, or secretion of fibrinogen. In addition to standard coagulation tests depending on the formation of fibrin, diagnostics also includes global coagulation assays, which are effective in monitoring the management of replacement therapy. Genetic testing is a key point for confirming the clinical diagnosis. The identification of the precise genetic mutations of congenital fibrinogen disorders is of value to permit early testing of other at risk persons and better understand the correlation between clinical phenotype and genotype. Management of patients with afibrinogenemia is particularly challenging since there are no data from evidence-based medicine studies. Fibrinogen concentrate is used to treat bleeding, whereas for the treatment of thrombotic complications, administered low-molecular-weight heparin is most often. This review deals with updated information about afibrinogenemia and hypofibrinogenemia, contributing to the early diagnosis and effective treatment of these disorders.

Compound Heterozygous Mutations in the F7 Gene in 2 Unrelated Families With Congenital Factor VII Deficiency

Factor VII (FVII) deficiency is a rare bleeding disorder normally caused by homozygous and compound heterozygous mutations in the F7 gene. Whole-exome sequencing was performed to identify F7 mutations in 3 individuals from 2 unrelated families who were diagnosed with FVII deficiency. Four compound heterozygous mutations were identified and validated in these 3 probands with FVII deficiency. Among the 4 identified mutations, NM_000131.4:c.572-1_581del, NM_000131.4:c.1250A>G (p.Tyr417Cys), and NM_000131.4:c.647G>T (p.Gly216Val) were novel. All 3 novel mutations were predicted to be likely pathogenic by the American College of Medical Genetics and Genomics/Association for Molecular Pathology guidelines.

Factor XIII Deficiency: A Review of Clinical Presentation and Management

Factor XIII (FXIII) deficiency is a rare autosomal recessive disorder that can result in life-threatening bleeding and early fetal loss. FXIII not only is responsible for cross-linking fibrinogen to stabilize and strengthen clot formation but also facilitates wound healing and angiogenesis and plays an important role in fetal vitality. Modern therapeutics allow for prophylactic treatment that can prevent most major bleeding and increasing fetal viability. Early diagnosis is paramount due to the high risk of intracranial bleeding.

Patient-centered approach to managing factor XIII deficiency

Factor XIII (FXIII) is a thrombin-activated protransglutaminase that plays a key role in blood clot formation. Congenital FXIII A-subunit deficiency represents a rare bleeding disorder that affects one in 2-3 million individuals worldwide and is treated with recombinant FXIII (rFXIII). However, due to the rarity of the disease, clinicians are often left to weigh individual variation in FXIII activity and/or symptoms to optimally guide dosing. Cases often become further complicated when patients experience refractory bleeding, which can be difficult to treat. This report describes an approach to rFXIII dosing in two patients who required deviation from standard protocols to maintain therapeutic FXIII troughs. We highlight limitations in our understanding of FXIII deficiency management, while also providing an example of the application of pharmacokinetic data to individualise therapy for improved outcomes. Finally, the case reminds us of the importance of patient-centered, cost-conscious care and multidisplinary teamwork in complex cases.

Mild Acquired Factor XIII Deficiency and Clinical Relevance at the ICU-A Retrospective Analysis

Acquired FXIII deficiency is a relevant complication in the perioperative setting; however, we still have little evidence about the incidence and management of this rarely isolated coagulopathy. This study aims to help find the right value for the substitution of patients with an acquired mild FXIII deficiency. In this retrospective single-center cohort study, we enrolled critically ill patients with mild acquired FXIII deficiency (>5% and ≤70%) and compared clinical and laboratory parameters, as well as pro-coagulatory treatments. The results of the present analysis of 104 patients support the clinical relevance of FXIII activity out of the normal range. Patients with lower FXIII levels, beginning at <60%, had lower minimum and maximum hemoglobin values, corresponding to the finding that patients with a minimum FXIII activity of <50% needed significantly more packed red blood cells. FXIII activity correlated significantly with general coagulation markers such as prothrombin time, activated partial thromboplastin time, and fibrinogen. Nevertheless, comparing the groups with a cut-off of 50%, the amount of fresh frozen plasma, thrombocytes, PPSB, AT-III, and fibrinogen given did not differ. These results indicate that a mild FXIII deficiency occurring at any point of intensive care unit stay is also probably relevant for the total need of packed red blood cells, independent of pro-coagulatory management. In alignment with the ESAIC guidelines, the measurement of FXIII in critically ill patients with the risk of bleeding and early management, with the substitution of FXIII at levels <50%-60%, could be suggested.

Factor VIII activity and bleeding risk during prophylaxis for severe hemophilia A: a population pharmacokinetic model

During factor VIII prophylaxis for severe hemophilia A, bleeding risk increases with time when factor VIII activity is below 1%. However, maintaining trough activity above 1% does not protect all patients from bleeding. The relationship between factor VIII activity during prophylaxis and bleeding risk has not been thoroughly studied. We investigated factor VIII activity and annualized bleeding rate for spontaneous bleeds during prophylaxis. A population pharmacokinetic model derived from three clinical trials was combined with dosing data and information on bleeding from patients’ diaries. Each patient’s time on prophylaxis was divided into five categories of predicted activity (0-1%, >1-5%, >5-15%, >15-50%, and >50%). Exposure time, mean factor VIII activity, and number of bleeds (from the patients’ diaries) were calculated for each activity category, and annualized bleeding rates estimated using negative binomial regression and a parametric model. Relationships between these bleeding rates and factor VIII activity were evaluated by trial phase (pivotal vs. extension) and age (adults/adolescents [≥12 years] vs. children [0-<12 years]). In total (n=187 patients; 815 patient-years’ exposure), factor VIII activity was predicted to be >1% for 85.64% of the time. The annualized bleeding rate decreased as factor VIII activity increased in each trial phase and age group. However, for a given activity level, bleeding rate differed substantially by trial phase and age. This suggests that bleeding risk can change over time and is influenced by factors independent of factor VIII pharmacokinetics and trough levels. When making decisions regarding target trough levels and the prophylactic regimen, the patients’ age, joint disease activity, and other bleeding risk determinants should be taken into consideration. Clinical trial registration numbers: NCT00840086; NCT01138501; NCT00984126

Occurrence and management of severe bleeding episodes in patients with hereditary factor X deficiency

Vitamin K-dependent factor X (FX) plays an important role in thrombin formation, and a deficiency in FX can cause impaired coagulation, the severity of which is usually correlated with the degree of deficiency. Due to the critical role that FX plays in the coagulation cascade, FX deficiency is associated with a higher risk of bleeding than deficiencies in other coagulation factors. Patients with the hereditary autosomal-recessive homozygous form of FX deficiency, which occurs in approximately 1:1,000,000 individuals worldwide, are often diagnosed when they present with spontaneous life-threatening haemorrhage (most often intracranial haemorrhage) during the first month of life. In addition to central nervous system bleeds, other severe bleeding types experienced by such patients may include umbilical cord bleeding, gastrointestinal or pulmonary haemorrhage, intramuscular haematomas and/or haemarthrosis. Delayed treatment or inadequate replacement of FX may result in developmental delays, musculoskeletal disabilities or death. The high risk of recurrent severe bleeding necessitates prophylactic replacement therapy for many individuals with severe FX deficiency. Available products for replacement therapy include plasma-derived FX concentrate and prothrombin complex concentrates. Fresh-frozen plasma may be used when concentrates are not available but is a less efficient means of FX replacement. This article reviews the literature on severe bleeding in individuals with hereditary FX deficiency and discusses current treatment options.

Plasma-derived factor X concentrate compassionate use for hereditary factor X deficiency: Long-term safety and efficacy in a retrospective data-collection study

BACKGROUND

Coagadex is a high-purity plasma-derived factor X concentrate (pdFX) developed to treat hereditary factor X deficiency (FXD).

OBJECTIVE

Evaluate the efficacy and safety of pdFX administered to patients with hereditary FXD.

METHODS

This was an open-label, multicenter, retrospective analysis of patients receiving pdFX for compassionate use. Efficacy end points included treatments administered, the number and treatment of bleeds, and investigator assessments. Adverse drug reactions (ADRs) were monitored.

RESULTS

Fifteen patients were included: seven received routine prophylaxis, seven received on-demand treatment, and one alternated. Most were aged ≥12 years (n = 13) and had severe hereditary FXD (n = 12). The median follow-up time was 19.2 months (range, 3.5-48.8). The number of infusions per patient per month was higher for the routine prophylaxis group (median [range], 5.4 [1.4-10.1]) than for the on-demand group (0.8 [0.1-2.3]), as was the dose per infusion (27.9 [21.9-53.6] IU/kg vs 20.0 [13.6-27.7] IU/kg). Patients experienced 88 bleeds (34 minor, 7 major, 47 unclassified). The monthly bleed rate per patient was 0.04 in the routine prophylaxis group (based on 17 bleeds in four patients) and 0.8 in the on-demand group (based on 71 bleeds in eight patients). pdFX was used to treat 79 bleeds and was rated effective in all instances. In an overall assessment, investigators rated pdFX as excellent for 14 patients (93.3%) and good for 1 patient (6.3%). No ADRs or safety concerns were reported.

CONCLUSIONS

This analysis supports the use of pdFX as a safe, effective treatment for hereditary FXD. Routine prophylaxis with pdFX may reduce bleed frequency.

Congenital Fibrinogen Deficiency in India and Role of Human Fibrinogen Concentrate

Congenital fibrinogen deficiency is an inherited disorder due to genetic mutations with diverse presentations arising from reduced fibrinogen levels (hypofibrinogenemia), absence of fibrinogen in circulation (afibrinogenemia), abnormal functioning (dysfibrinogenemia) or both reduced levels and abnormal functioning (hypodysfibrinogenemia) of fibrinogen. The decreased fibrinogen concentration in congenital fibrinogen deficiency necessitates fibrinogen replacement therapy with fresh frozen plasma, cryoprecipitate, or human fibrinogen concentrate. However, the use of fresh frozen plasma and cryoprecipitate is limited owing to their longer transfusion time, requirement of high doses, volume overload, risk of viral transmission, and other safety concerns. The availability of human fibrinogen concentrate has made it the preferred replacement alternative due to its reduced risk of viral transmission, smaller infusion volume, and accurate dosing. The hemostatic efficacy and safety of human fibrinogen concentrate in congenital fibrinogen deficiency is well established in the literature. We review the prevalence of congenital fibrinogen deficiency in India and the current role of human fibrinogen concentrate in its management.

Pharmacometric modeling to explore 4F-PCC dosing strategies for VKA reversal in patients with INR below 2

The indicated dose of 4-factor prothrombin complex concentrate (4F-PCC) for urgent vitamin K antagonist (VKA) reversal in patients with an international normalized ratio (INR) of 2 to 4 is 25 IU/kg, but there is no indicated dose for INR <2. We explored 4F-PCC dosing strategies for baseline INR <2. Clinical trial data were used to develop pharmacometric models for Factor X (FX) and FII, accounting for covariates including baseline INR. FX and FII levels over time were simulated for mean baseline INR levels of the clinical trial participants plus baseline INRs 3.1, 1.9, and 1.6. For each INR, 200 virtual male patients were simulated to evaluate 4F-PCC doses of 35, 25, 20, 15, 12.5, and 10 IU/kg. Given an elevated bleeding risk with VKA therapy in Japanese vs Western populations, results were stratified by Japanese and non-Japanese patients. Target levels of FX and FII were ≥50% activity at 30 minutes after dosing in ≥80% of patients. FX- and FII-time models were developed with 1088 FX observations from 193 patients and 1074 FII observations from 192 patients. Model-based simulations indicated that at baseline INR 3.1, ≥80% of patients achieved ≥50% FX and FII activity with 25 IU/kg and 20 IU/kg 4F-PCC, respectively; at baseline INR 1.9, corresponding doses were 20 IU/kg and 15 IU/kg 4F-PCC, and at baseline INR 1.6, corresponding doses were 15 IU/kg, and 10 IU/kg 4F-PCC. Trends in Japanese and non-Japanese patients were similar. In conclusion, low 4F-PCC doses (15-20 IU/kg) may be sufficient to achieve hemostatic levels of FX and FII in Japanese and non-Japanese patients with baseline INR <2.