Bleeding in carriers of hemophilia

Application of machine learning approaches for predicting hemophilia A severity

BACKGROUND

Hemophilia A (HA) is an X-linked congenital bleeding disorder, which leads to deficiency of clotting factor (F) VIII. It mostly affects males, and females are considered carriers. However, it is now recognized that variants of F8 in females can result in HA. Nonetheless, most females go undiagnosed and untreated for HA, and their bleeding complications are attributed to other causes. Predicting the severity of HA for female patients can provide valuable insights for treating the conditions associated with the disease, such as heavy bleeding.

OBJECTIVES

To predict the severity of HA based on F8 genotype using a machine learning (ML) approach.

METHODS

Using multiple datasets of variants in the F8 and disease severity from various repositories, we derived the sequence for the FVIII protein. Using the derived sequences, we used ML models to predict the severity of HA in female patients.

RESULTS

Utilizing different classification models, we highlight the validity of the datasets and our approach with predictive F1 scores of 0.88, 0.99, 0.93, 0.99, and 0.90 for all the validation sets.

CONCLUSION

Although with some limitations, ML-based approaches demonstrated the successful prediction of disease severity in female HA patients based on variants in the F8. This study confirms previous research findings that ML can help predict the severity of hemophilia. These results can be valuable for future studies in achieving better treatment and clinical outcomes for female patients with HA, which is an urgent unmet need.

Bleeding risk in hemophilia A and B carriers: comparison of factor levels determined using chronometric and chromogenic assays

BACKGROUND

Predicting the bleeding risk in hemophilia A and B carriers (HAC, HBC) is challenging.

OBJECTIVE

The objectives of this study were to describe the bleeding phenotype in HAC and HBC using the standardized Tosetto bleeding score (BS); to determine whether the BS correlates better with factor levels measured with a chromogenic assay than with factor levels measured with chronometric and thrombin generation assays; and to compare the results in HAC and HBC.

METHODS

This ambispective, noninterventional study included obligate and sporadic HAC and HBC followed at a hemophilia treatment center between 1995 and 2019.

RESULTS AND CONCLUSION

The median BS (3, range 0-21 vs. 3.5, range 0-15, P  = ns, respectively) and the abnormal BS rate (35.6% vs. 38.2%, P  = ns) were not significantly different in 104 HAC and 34 HBC (mean age: 38 years, 6-80 years). However, some differences were identified. The risk of factor deficiency was higher in HBC than HAC. Specifically, Factor VIII activity (FVIII):C/Factor IX activity (FIX):C level was low (<40 IU/dl) in 18.3% (chronometric assay) and 17.5% (chromogenic assay) of HAC and in 47% and 72.2% of HBC ( P  < 0.001). Moreover, the FIX:C level thresholds of 39.5 IU/dl (chronometric assay) and of 33.5 IU/dl (chromogenic assay) were associated with very good sensitivity (92% and 100%, respectively) and specificity (80% for both) for bleeding risk prediction in HBC. Conversely, no FVIII:C level threshold could be identified for HAC, probably due to FVIII:C level variations throughout life.

Identifying hemophilia B carriers: Utility of aPTT, factor IX levels and ratios of factor IX to other Vitamin K dependent factors

INTRODUCTION

Diagnosing hemophilia B (HB) carrier status is important to manage bleeding in carriers and to prevent bleeding in potential offspring. Without a family history of hemophilia, diagnosing HB carrier status is challenging. Genetic testing is the gold-standard, however it is reserved for individuals with a high suspicion of carrier status.

AIMS

To describe the distribution of activated partial thromboplastin time (aPTT) and factor IX coagulant (FIX:C) levels in HB carriers and assess the ratio of FIX:C to other Vitamin K dependent factors (FII:C, FVII:C, FX:C) as an indicator of HB carrier status.

METHODS

In this retrospective, single-centre cohort study, subjects were included if they were obligate or genetically proven HB carriers. Distributions of aPTT and FIX:C were described and the relationship between FIX:C levels in carriers and severity of familial HB was analysed. Ratios of FIX:C to FII:C, FVII:C, FX:C were calculated.

RESULTS

Seventy-two female HB carriers (median age: 34 years; IQR 24-43) were included. Median aPTT and FIX:C levels were 33.0 s [IQR 30.0-37.0] and 57 IU/dL [IQR 43-74]. Fifteen carriers (21%) had mild HB (FIX:C levels of 10-40 IU/dL). FIX:C levels trended higher in carriers of mild HB versus carriers of moderate/severe HB. In six carriers, the median ratio of FIX:C to other Vitamin K dependent factors was 0.44, with 92% of ratios being ≤ 0.75.

CONCLUSION

aPTT and FIX:C levels were unreliable in diagnosing HB carrier status. A low ratio of FIX:C to other Vitamin K dependent factors may be a useful marker of HB carrier status.

Clinical analysis and quality of life survey of hemophilia B patients in the central and western regions of China

Objective

To study the current status of hemophilia B (HB) patients in the central and western regions of China.

Methods

This cross-sectional, multicenter study was conducted in seven provinces in the central and western regions of China from April 2019 to June 2023. Samples were collected for the factor IX activity, inhibitor screen, and gene mutation. Furthermore, the status of six index joints and quality of life (QoL) were assessed.

Results

A total of 185 HB patients (mild 15, moderate 75, and severe 95) with a median age of 12.17 years were enrolled. 30.3% (56/185) of patients had a family history of HB. 34.6% (64/185) of HB patients had diagnostic delay and 38.5% (69/179) experienced treatment delay. The incidence of inhibitors was 6.1% (11/179). We identified 123 genetic variants in this study, with missense mutations being the most common. 84.0% (89/106) of HB mothers were genetically identified as carriers, with 27.7% (13/47) of carriers having clotting factor levels less than 0.40 IU/ml. 71.4% (132/185) of HB patients had a history of joint hemorrhage, with a rate of target joint in these patients was 64.4% (85/132). Lower extremity joints were most often affected in patients. The Hemophilia Joint Health Score (HJHS) score was significantly positively correlated with the Hemophilia Early Arthropathy Detection with Ultrasound in China (HEAD-US-C) (r = 0.542, P < 0.001). Patients who received prevention treatment, inhibitor negative, without treatment delay, and without high-intensity replacement therapy showed a higher total score of the short form-36 health survey (SF-36).

Conclusions

One-third of HB patients had delay in diagnosis and treatment, and the incidence of inhibitors was 6.1%. Target joints were present in nearly half of HB patients. Missense was the main mutation type. 84.0% of mothers of HB patients in this study were found to be carriers. HEAD-US-C and HJHS can complement each other in the evaluation of joint status and give a valid basis for early clinical management. Early detection and preventive treatment, as well as reducing high-intensity replacement therapy and inhibitor generation, can effectively improve the QoL of patients.

Gender equity in hemophilia: need for healthcare, familial, and societal advocacy

Hemophilia is a rare bleeding disorder caused by a genetic defect on chromosome X. It is inherited as an X-linked trait, and hence, it is more frequently diagnosed in males, whereas women have been traditionally considered only as carriers of the disease. However, the role of women in families of patients with hemophilia is pivotal. As mothers, sisters, daughters, and female partners of patients with hemophilia, they play a central role in the management of the patient, considering healthcare, social, and familial aspects, but they might be affected by the disease as well, particularly in regions where consanguinity is frequent. This paper aims to explore the involvement of women in hemophilia, including their carrier status, bleeding symptoms, treatment challenges, and psychosocial impact not only related to male patients, but also as patients affected with hemophilia themselves. We advocate health equity, equal access to healthcare for men and women with hemophilia and dedicated resources to improve the unique needs of the women dealing with hemophilia, ultimately leading to improved care and quality of life.

Clinical Analysis and Mental Health Survey of Hemophilia Carriers: a Cross-sectional Study

OBJECTIVE

Hemophilia carriers (HCs), who are heterozygous for mutations in the clotting factor VIII/clotting factor IX gene (F8 or F9), may have a wide range of clotting factor levels, from very low, similar to afflicted males, to the upper limit of normal, and may experience mental health issues. The purpose of this study was to provide genetic information on mothers of hemophilia patients and to understand the clotting factor activity and phenotype of HCs. Additionally, we aimed to investigate the mental health status of HCs in China.

METHODS

A total of 127 hemophilia mothers, including 93 hemophilia A (HA) mothers and 34 hemophilia B (HB) mothers, were enrolled in this study. Long distance PCR, multiplex PCR, and Sanger sequencing were used to analyze mutations in F8 or F9. Coagulation factor activity was detected by a one-stage clotting assay. The Symptom Checklist 90 (SCL-90, China/Mandarin version) was given to HCs at the same time to assess their mental health.

RESULTS

A total of 90.6% of hemophilia mothers were diagnosed genetically as carriers, with inversion in intron 22 and missense mutations being the most common mutation types in HA and HB carriers, respectively. The median clotting factor level in carriers was 0.74 IU/mL (ranging from 0.09 to 1.74 IU/mL) compared with 1.49 IU/mL (ranging from 0.93 to 1.89 IU/mL) in noncarriers, of which 14.3% of HCs had clotting factor levels of 0.40 IU/mL or below. A total of 53.8% (7/13) of HA carriers with low clotting factor levels (less than 0.50 IU/mL) had a history of bleeding, while none of the HB carriers displayed a bleeding phenotype. The total mean score and the global severity index of the SCL-90 for surveyed HCs were 171.00 (±60.37) and 1.78 (±0.59), respectively. A total of 67.7% of the respondents had psychological symptoms, with obsessive-compulsive disorder being the most prevalent and severe. The pooled estimates of all nine factors were significantly higher than those in the general population (P<0.05).

CONCLUSIONS

The detection rate of gene mutations in hemophilia mothers was 90.6%, with a median clotting factor level of 0.74 IU/mL, and 14.3% of HCs had a clotting factor level of 0.40 IU/mL or below. A history of bleeding was present in 41.2% of HCs with low clotting factor levels (less than 0.50 IU/mL). Additionally, given the fragile mental health status of HCs in China, it is critical to develop efficient strategies to improve psychological well-being.

The role of viscoelastic hemostatic assays for postpartum hemorrhage management and bedside intrapartum care

Viscoelastic hemostatic assays are point-of-care devices that assess coagulation and fibrinolysis in whole blood samples. These technologies provide numeric and visual information of clot initiation, clot strength, and clot lysis under low-shear conditions, and have been used in a variety of clinical settings and subpopulations, including trauma, cardiac surgery, and obstetrics. Emerging data indicate that these devices are useful for detecting important coagulation defects during major postpartum hemorrhage (especially low plasma fibrinogen concentration [hypofibrinogenemia]) and informing clinical decision-making for blood product use. Data from observational studies suggest that, compared with traditional formulaic approaches to transfusion management, targeted or goal-directed transfusion approaches using data from viscoelastic hemostatic assays are associated with reduced hemorrhage-related morbidity and lower blood product requirement. Viscoelastic hemostatic assays can also be used to identify and treat coagulation defects in patients with inherited or acquired coagulation disorders, such as factor XI deficiency or immune-mediated thrombocytopenia, and to assess hemostatic profiles of patients prescribed anticoagulant medications to mitigate the risk of epidural hematoma after neuraxial anesthesia and postpartum hemorrhage after delivery.

Variant spectrum of F8 and F9 in hemophilia patients from southern China and 26 novel variants

Hemophilia, an X-linked recessive disorder, is characterized by spontaneous or trauma-induced prolonged bleeding. It is classified as hemophilia A when caused by variants in the F8 gene, and hemophilia B when caused by F9 variants. Few studies have described hemophilia variants in the Chinese population. This study aimed to investigate the clinical and genetic profiles of 193 hemophilia patients from southern China. Utilizing Sanger sequencing, multiplex ligation-dependent probe amplification, gap detection, long-range PCR, and multiplex PCR, we identified both F8 and F9 gene variants. Pregnant women with a history of hemophilia A offspring underwent amniocentesis or villus sampling for the variant detection. Variants in F8 and F9 were pinpointed in 183 patients, with 26 being novel discoveries. Notably, genetic testing was absent in the initial evaluation of 133 out of 161 patients, leading to a protracted average definitive diagnosis timeline of 2 years. Remarkably, two hemophilia A cases with anticipated severe phenotypes due to protein-truncating variants presented with only moderate or mild clinical manifestations. Among the 40 fetuses tested, 34 were males, with 17 exhibiting hemizygous variants in the F8 gene. Our results contribute to the broader understanding of F8 and F9 variant spectrum and highlight the underuse of genetic analyses in southern China.

Current Status and Challenges in Delivering Comprehensive Care for Patients with Hemophilia

The importance of comprehensive care as a treatment strategy for patients with hemophilia is recognized worldwide. Comprehensive care entails addressing full spectrum of medical and psychological aspects impacting both patients and their families. The primary objective of comprehensive care for individuals with hemophilia is to enable them to lead their daily lives just as anyone else would. To achieve this goal, it is necessary to have a positive and collaborative approach across various healthcare disciplines. This extends beyond clinical specialists, encompassing pediatricians, hematologists, orthopedic surgeons, dental and oral surgeons, gynecologists, nurses, physical therapists, clinical psychologists, and other professionals from diverse fields. This review article discusses the current status and challenges associated with comprehensive care for patients with hemophilia. We categorize these challenges as follows: hemophilic arthritis, rehabilitation, oral care, transitioning from pediatric to adult care, addressing carrier issues, and providing psychological care. There is still substantial work to be undertaken in addressing these hurdles and advancing the quality of comprehensive care for hemophilia patients.

The frequency of complications in a cohort of patients diagnosed with hemophilia A and hemophilia B receiving prophylactic treatment in Colombia: A retrospective noninterventional study

INTRODUCTION

Hemophilia A and B are disorders associated with the deficit of coagulation factors VIII and IX.

OBJECTIVE

Was to determine the incidence of complications in a cohort of patients diagnosed with moderate and severe hemophilia A or B under treatment in a specialized institution.

METHODS

A retrospective study of a cohort of patients with replacement therapy for hemophilia A or B, evaluating treatment and complications between January/2012 and July/2019. Sociodemographic, clinical and disease management-related variables were extracted from the medical records. Time to inhibitor development and rate associated with bleeding and hospitalizations were evaluated.

RESULTS

A total of 159 male patients were identified with hemophilia A (n = 140; 88.1%) and B (n = 19; 11.9%) with a mean follow-up of 5.9±2.3 years. The mean age was 23.6±16.1 years, hemophilia was reported as severe in 125 patients in hemophilia A (89.3%) and 13 patients in hemophilia B (68.4%). Primary prophylaxis was registered in 17.0% of patients, 44.7% secondary, and 38.3% tertiary, with recombinant factors (n = 84; 52.8%) followed by plasma derived factors (n = 75; 47.2%). The incidence of inhibitor development was 0.3 per 100 patients/year, with mean time to event of 509 days. The incidence of bleeding was 192 per 100 patients/year, especially at the joint (n = 99; 62.3%) and muscle (n = 25; 15.7%) level. The incidence of hospitalization was 3.7 per 100 patients/year.

CONCLUSIONS

The most common complication was joint bleeding which was expected in this type of patients. Low proportion of patients developed factor inhibitors during the follow up.

Factor activity levels and bleeding scores in pediatric hemophilia carriers enrolled in the ATHNdataset

BACKGROUND

Multiple studies have now shown that a significant proportion of hemophilia carriers meet the criteria for having hemophilia and/or report abnormal bleeding. However, to date, investigations of hemophilia carriers have almost exclusively involved women over 18 years of age. Little is known about factor activity levels and bleeding scores in carriers during childhood. We queried a large deidentified database of subjects with bleeding disorders residing in the United States to determine factor activity levels and bleeding scores.

PROCEDURES

The ATHNdataset was queried for hemophilia carriers under 18 years of age. Collected information included demographics, factor activity levels, and bleeding scores.

RESULTS

Over 700 carriers in the pediatric age group were identified, of which 626 submitted factor activity levels. Nearly half had factor activity levels less than 40 IU/dL, thereby meeting criteria for having hemophilia. Of those reporting bleeding scores, only 13.5% reported an abnormal bleeding score for age. The proportion reporting abnormal bleeding scores was higher in those with factor levels less than 40 IU/dL (23%) than those greater than 40 IU/dL (9.7%).

CONCLUSIONS

The proportion of pediatric carriers with hemophilia was double of that previously reported for adults. Of those with hemophilia reporting a bleeding score, the majority (77%) did not report an abnormal bleeding score for age. However, nearly 10% of pediatric carriers not meeting criteria for having hemophilia reported abnormal bleeding scores for age. Similar results are reported in adults suggesting that factor activity levels may not be predictive of bleeding symptoms in carriers.

Sensitive Measurement of Clinically Relevant Factor VIII Levels in Thrombin Generation Assays Requires Presence of Factor XIa

BACKGROUND

 Hemophilia A (HA) is characterized by decreased or absent factor VIII (FVIII) activity. Current FVIII assays are based on clotting time and thus only provide information about the initiation of coagulation. In contrast, thrombin generation assays (TGAs) can be used to measure the full coagulation spectrum of initiation, propagation, and termination that provide information on the whole course of thrombin generation and inhibition. However, the commercially available TG kits lack sensitivity for measurements of hemophilia plasma within lower FVIII ranges, which is essential for explaining differences in bleeding phenotypes in hemophiliacs at clinically low levels of FVIII.

AIMS

 Optimization of the TGA for measurements of low FVIII levels in severe HA patients.

METHODS

 TGA measurements were performed in severe HA pooled plasma (n = 10). Investigations of several preanalytical and analytical variables of the assay were performed in a stepwise process and adjusted based on sensitivity toward intrinsic coagulation activation.

RESULTS

 TGA initiated by tissue factor (TF) alone at varying concentrations was unable to significantly differentiate between FVIII levels below 20%. In contrast, TGA activation with low concentrations of TF in presence of FXIa appeared to be highly sensitive for FVIII changes both in high and low ranges. In addition, a representative TGA curve at trough levels could only be produced using the dual TF/FXIa TGA.

CONCLUSION

 We propose a critical optimization for the setup of the TGA for measurements in severe HA plasma. The dual TF/FXIa TGA shows increased sensitivity, especially in lower FVIII ranges, which allows for better individual characterization at baseline, prediction of interventions, and follow-up.

Racial and ethnic differences in reported haemophilia death rates in the United States

INTRODUCTION

People with haemophilia's life expectancies have improved over time. Whether progress has been experienced equitably is unknown.

AIM

To examine recorded haemophilia death (rHD) rates according to race and ethnicity in the United States (US).

METHODS

In this cohort study, rHDs were examined with US National Vital Statistics' 1999-2020 Multiple Cause-of-Death data. rHD was defined as having a haemophilia A (D66) or B (D67) ICD-10 code in the death certificate (underlying or multiple causes of death). Age-adjusted rHD rates were compared with age-adjusted rate ratios (aRR) and 95% Confidence Intervals (CI).

RESULTS

There were 3115 rHDs in males with an rHD rate of 0.98 per 1 million males. Between 1999 and 2020, rHD rates declined by 46% in NH (Non-Hispanic) White, 44% in NH Black (aRR = 0.56, 95%CI 0.43, 0.74), and 42% in Hispanic (aRR = 0.58, 95%CI 0.39, 0.88) males. However, rHD rates remained higher and were on average 30% greater in NH Black versus NH White males (aRR = 1.30 95% CI 1.16, 1.46). Among males with rHD, the median age at death rose from 54.5 to 65.5 years between 1999 and 2020 and was 12 years lower in NH Black (56 years) versus NH White (68 years) males in 2010-2020. There were 930 females with rHD, with an age-adjusted rate of 0.22 per 1 million females, which was consistent between 1999 and 2020.

CONCLUSION

Reported haemophilia-death rates improved in males across all race/ethnicities, but rates were higher Black versus White males. Given the inherent limitations of the current study's data source, further investigation of survival rates and disparities in haemophilia are needed.

Closing the Diagnostic Gap in Adolescents and Young Adult Women With Bleeding Disorders: Missed Opportunities

Approximately 2% of the general population have an underlying inherited bleeding disorder, which, for adolescents and young adult women, has both physical risks and adverse psychosocial effects. Heavy menstrual bleeding can be the first sign of an underlying bleeding disorder such as von Willebrand disease and the X-linked bleeding disorders hemophilia A and B. Connective tissue disorders such as Ehlers-Danlos syndrome, in particular the hypermobile subtype, are relatively frequent in the general population and can also cause bleeding symptoms from impaired hemostasis due to defective collagen. For more than 20 years, the American College of Obstetricians and Gynecologists (ACOG) has recommended screening adolescents and young adult women for bleeding disorders when they present with heavy menstrual bleeding. Despite this directive, there is a significant gap from symptom onset to time of diagnosis in this patient population. We must work to effectively close this diagnostic gap by consistently obtaining thorough bleeding histories, performing the appropriate laboratory evaluations, working collaboratively with hematologists, and using tools and materials promoted by ACOG. Improved screening and earlier diagnosis of these individuals can have far-reaching effects that are not limited to heavy menstrual bleeding management and extend to peripartum considerations and prenatal counseling.

National strategic advocacy to manage patients with inherited bleeding disorders in low and lower-middle income countries

INTRODUCTION

Inherited bleeding disorders (IBDs) including hemophilia, von Willebrand disease, platelet disorders, mucocutaneous bleeding disorders and coagulation factor deficiencies are rarely found and under-recognized in low and lower-middle-income countries. Some patients succumbed to serious bleeding without diagnosis and treatment during childhood.

AREA COVERED

Diagnosis, management, and prevention should be integrated into the existing health care system. Although some countries have not implemented appropriate health care infrastructure, an initiative plan should be set up by cooperation of experienced experts and health care providers. Identification of patients with IBDs should be started in the antenatal setting to search for females at risk of carrier state. The investigations include bleeding assessment, mixing venous clotting time, coagulogram, coagulation factor assay and mutation detection. Genotypic analysis is helpful for confirming the definite diagnosis, carrier detection as well as prenatal diagnosis for females at risk of bearing an offspring with severe bleeding manifestations. Management involves replacement therapy ranging from blood component to virus-inactivated factor concentrate. Appropriate research is an essential backbone for improving patients' care.

EXPERT OPINION

Effective national strategic advocacy to manage patients with IBDs requires intensive collaboration among policy makers, health care providers, patients, and family members.

Association of Genetic Variant FVIII Gene and Factor VIII: A Pilot Study Among Hemophilia A Female Relatives in Saudi Arabia

Hemophilia A (HA) is an X-linked recessive disorder that results from mutations in the factor VIII gene (FVIII). Most affected patients are males due to the inheritance of mutations in the FVIII gene from their mothers. Females are mostly found to be carriers unless they inherited the mutation from both parents. Obligate carriers of HA are mothers whose sons are affected with HA, or daughters who inherit the mutation from their affected fathers. A possible carrier of HA could be any female who has one or more affected relatives with HA in her family. Hemophilia A carriers (HACs) could present with similar symptoms to affected patients, including low factor VIII level, and risk of bleeding especially after surgical procedures or postpartum hemorrhage.

OBJECTIVES

 Assessing the phenotype of possible HAC and its association with genetic variants in the FVIII gene for better screening methods for HAC.

METHODS

From the period between 25 June and 25 October 2021, the study was conducted at King Abdulaziz University Hospital in Jeddah, Saudi Arabia. We recruited seven mothers whose sons were affected with HA, and 18 possible HAC who are relatives to sever affected patients with HA. All 25 candidates were assessed for the FVIII level, activated partial thromboplastin time (APTT), and bleeding risk and sequenced a part of Exon14 in their FVIII gene.

RESULTS

Twenty-five percent of the participants show a low level of FVIII, however, none of them have prolonged bleeding nor suffer from bleeding tendency. We also identified two missense variants in six of the candidates, but the clinical significance of these variants has not been determined previously.

CONCLUSION

This pilot study is the first to explore the phenotype of several HAC in Saudi Arabia. A larger scale study with more HA patients and their female relatives is needed to understand the correlation between phenotype and genotype for better screening for HAC.

Clotting Factor Deficiencies as an Underlying Cause of Abnormal Uterine Bleeding in Women of Reproductive Age: A Literature Review

Clotting Factor deficiencies are rare disorders with variations in clinical presentation and severity of symptoms ranging from asymptomatic to mild to life-threatening bleeding. Thus, they pose a diagnostic and therapeutic challenge, mainly for the primary health care providers, general practitioners, and gynecologists who are more likely to first encounter these patients. An additional diagnostic challenge arises from the variable laboratory presentations, as PT, PTT, and BT are not always affected. The morbidity is higher among women of reproductive age since Abnormal Uterine Bleeding-specifically Heavy Menstrual Bleeding-is one of the most prevalent manifestations of these disorders, and in some cases of severe deficiencies has led to life-threatening episodes of bleeding requiring blood transfusions or even immediate surgical intervention. Physician awareness is important as, in the case of some of these disorders-i.e., Factor XIII deficiency-prophylactic treatment is available and recommended. Although uncommon, the potential for rare bleeding disorders and for hemophilia carrier states should be considered in women with HMB, after more prevalent causes have been excluded. Currently, there is no consensus on the management of women in these instances and it is reliant on the physicians' knowledge.

Evaluation of clinical characteristics, health care resource utilization, and cost outcomes of hemophilia A carriers and noncarriers in the United States: A real-world comparative analysis

BACKGROUND: Hemophilia A is often viewed as a male disease; females are usually considered asymptomatic hemophilia A carriers. However, hemophilia A carriers may experience mild-to-severe bleeding events. OBJECTIVE: To compare clinical characteristics, health care resource utilization, and costs incurred by hemophilia A carriers compared with a non-hemophilia A carrier female control population in the United States. METHODS: This retrospective observational cohort study used data from IBM MarketScan Commercial Claims and Encounters and Multi-State Medicaid Databases from January 1, 2016, to September 30, 2019. Patients with a hemophilia A carrier diagnosis were matched to a non-hemophilia A carrier female control group in a 1:2 ratio based on sociodemographic characteristics, pregnancy status, and insurance type. Billed annualized bleed rates, health care resource utilization, and annualized costs were evaluated. Generalized linear models compared annualized total costs in the hemophilia A carrier and control groups. RESULTS: After matching, the hemophilia A carrier group included 121 (Commercial) and 55 (Medicaid) patients, matched 1:2 in the control group. Patients in the hemophilia A carrier group (compared with the control group) had numerically higher joint-related health issues (Commercial: 11.6% vs 7.9%; Medicaid: 7.3% vs 4.5%) and lower soft-tissue disorders (Commercial: 13.2% vs 17.4%; Medicaid: 12.7% vs 14.5%). Musculoskeletal pain was higher (33.1% vs 31.0%) and lower (21.8% vs 25.5%) in the Commercial and Medicaid databases, respectively. Billed annualized bleed rates were higher in the hemophilia A carrier group (Commercial: 0.49 vs 0.33; Medicaid: 0.50 vs 0.29). Significantly more patients in the hemophilia A carrier group had minor bleeds (Commercial: 34.7% vs 22.3% [P = 0.001]; Medicaid: 43.6% vs 20.0% [P < 0.001]) and spontaneous bleeds (Commercial: 35.5% vs 21.5%; Medicaid: 47.3% vs 23.6% [P < 0.001 for both]). Outpatient visits represented the majority of health care resource utilization and were higher in the hemophilia A carrier group for all-cause and bleed-related claims; although less frequent, emergency department and inpatient visits followed a similar trend. In the Commercial and Medicaid databases, hemophilia A carriers incurred approximately 2 times higher mean (SD) all-cause health care total costs than patients in the control group (Commercial: $15,345 [21,871] vs $8,358 [11,939] per patient per year [PPPY]; Medicaid: $9,022 [19,461] vs $4,533 [9,532] PPPY). CONCLUSIONS: Hemophilia A carriers experienced more complications and incurred higher costs (resulting from more outpatient, emergency department, and inpatient visits) compared with patients in the control group. These data suggest that hemophilia A carriers have a high disease and economic burden and may benefit from early diagnosis and management to prevent long-term complications. DISCLOSURES: Dr Xing, Dr Bullano, Dr Caicedo, and Mr Farahbakhshian are employees of Takeda Pharmaceuticals U.S.A., Inc., hold Takeda stocks, and have been granted restricted stock shares; Drs Xing and Caicedo received support from Takeda Pharmaceuticals U.S.A., Inc., for travel to THSNA 2022, where the data included in this manuscript were presented. Dr Batt received consulting fees from Complete HEOR Solutions (CHEORS) LLC for the protocol development, data analysis, and interpretation of this study; she also holds stocks from Merck and Sanofi. Ms Kuharic is an employee of the University of Illinois at Chicago and has been supported by a Takeda fellowship during the execution of the study. Ms Chakladar and Ms Markan were employees of CHEORS LLC at the time of the study. CHEORS has received funding from Takeda Pharmaceuticals U.S.A., Inc., for conducting the analysis of this study. This study was funded by Takeda Pharmaceuticals U.S.A., Inc. The sponsor was involved in the study design; collection, analysis, and interpretation of data; development and review of the manuscript; and decision to submit manuscript to publication.

A novel F8 variant in a Chinese hemophilia A family and involvement of X-chromosome inactivation: A case report

RATIONALE

Hemophilia A (HA) is an X-linked recessive bleeding disorder, which shows factor VIII (FVIII) deficiency caused by genetic variant in F8 gene.

PATIENT CONCERNS

Males with F8 variants are affected, whereas female carriers with a wide range of FVIII levels are usually asymptomatic, it is possible that different X-chromosome inactivation (XCI) may effect the FVIII activity.

DIAGNOSES

We identified a novel variant F8: c.6193T > G in a Chinese HA proband, it was inherited from the mother and grandmother with different FVIII levels.

INTERVENTIONS

We performed Androgen receptor gene (AR) assays and RT-PCR.

OUTCOMES

AR assays revealed that the X chromosome with the F8 variant was severely skewed inactivated in the grandmother with higher FVIII levels, but not in the mother with lower FVIII levels. Further, RT-PCR of mRNA confirmed that only the wild allele of F8 was expressed in the grandmother, with lower expression in the wild allele of the mother.

LESSONS

Our findings suggest that F8: c.6193T > G could be the cause of HA and that XCI affected the FVIII plasma levels in female carriers.

Real-world analysis of patients with haemophilia A and haemophilia A carriers in the United States: Demographics, clinical characteristics and costs

INTRODUCTION

Females with haemophilia A (HA [FHAs]) and HA carriers (HACs) have an increased risk of bleeding and complications compared to the general population.

AIM

To examine the characteristics, billed annualised bleed rates (ABRb ), costs and healthcare resource utilisation for males with HA (MHAs), FHAs and HACs in the United States.

METHODS

Data were extracted from the IBM® MarketScan® Research Databases (Commercial and Medicaid) for claims during the index period (July 2016 to September 2018) and analysed across MHAs, FHAs and HACs.

RESULTS

Dual diagnosis females (DDFs; both HA and HAC claims) were grouped as a separate cohort. MHAs were generally younger than females (all cohorts) by up to 19 years (Commercial) and 23 years (Medicaid). ABRb  >0 was more frequent in females. Factor VIII claims were higher for MHAs versus female cohorts. Joint-related health issues were reported for 24.4 and 25.6% (Commercial) and 29.3 and 26.6% (Medicaid) of MHAs and FHAs, respectively; lower rates were reported in the other two cohorts. Heavy menstrual bleeding claims occurred for approximately a fifth (Commercial) to a quarter (Medicaid) of female cohorts. All-cause emergency department and inpatient visits in FHAs and DDFs were similar to, or more frequent than, those in MHAs; bleed-related inpatient visits were infrequent. In MHAs (Commercial), mean all-cause total costs ($214,083) were higher than in FHAs ($40,388), HACs ($15,647) and DDFs ($28,320) with similar trends for Medicaid patients.

CONCLUSIONS

FHAs and HACs may be undermanaged and undertreated. Further research is needed to fully understand these cohorts' bleeding rates, long-term complications and costs.

Women and girls with haemophilia: A retrospective cohort study in China

INTRODUCTION

Women and girls with haemophilia (WGH) may have spontaneous/traumatic bleeding similar to that in males with haemophilia, and in addition excessive bleeding during menstruation and delivery.

AIM

To characterize WGH in China and provide guidance for better management.

METHODS

We retrospectively analysed the characteristics of WGH registered in the Haemophilia Treatment Center Collaborative Network of China (HTCCNC) Registry, including demographics, diagnosis and treatment, bleeding characteristics, obstetrical and gynaecological experiences, and surgical history.

RESULTS

A total of 61 females had confirmed haemophilia. Diagnosis and treatment were typically delayed, longer in mild haemophilia than in severe and moderate. The most frequently reported bleeding manifestations were haemarthrosis in severe and moderate patients, and cutaneous bleeding in mild patients. Among 45 postmenarcheal WGH, 21 (46.7%) had history of heavy menstrual bleeding, but only three received treatments. Prenatal diagnosis and management of perinatal haemorrhage were inadequate. Of 34 deliveries in 30 women, nine deliveries were complicated by postpartum haemorrhage, and 22 offspring carried mutations causing haemophilia. Forty-four surgical procedures were performed in 29 patients. Those procedures receiving preoperative coagulation factors coverage were significantly less likely to have excessive bleeding than those who did not (P = .003).

CONCLUSION

This is the first and largest study describing WGH in China. There are currently deficiencies in the identification, diagnosis, and management of these patients. Improving health insurance policies, establishing haemophilia centres, and multidisciplinary teams for bleeding and perinatal or perioperative management will help reduce morbidity and mortality.

Reproductive Tract Bleeding in Adolescent and Young Adult Females with Inherited Bleeding Disorders: An Underappreciated Problem

Reproductive tract bleeding is an underappreciated health care problem among adolescent and young adult (AYA) females with inherited bleeding disorders (IBDs) comprising von Willebrand disease, platelet disorders, hemophilia carriership, and rare factor deficiencies. IBDs are prevalent in women of all ages and have been detected in about 50% of women with menorrhagia or heavy menstrual bleeding (HMB) and about 20% of women with postpartum hemorrhage (PPH). The clinical spectrum of gynecologic and obstetric bleeding in AYA with IBDs ranges from HMB, ovulation bleeding, and surgical bleeding to miscarriages and life-threatening PPH. Reproductive tract bleeding adversely affects the quality of life of this patient population, in addition to causing substantial morbidity and mortality. Early diagnosis of IBDs offers the opportunity for timely intervention with hormones, hemostatic agents, and prophylaxis with factor concentrates, thereby improving outcomes. This review summarizes the epidemiology, pathophysiology, clinical manifestations, diagnostic approach, management, and prophylaxis for reproductive tract bleeding in AYA with IBDs. This review provides a multidisciplinary approach to the problem, which is critical to improve the outcomes of this patient population.

A Novel Deletion Mutation of the F8 Gene for Hemophilia A

Background: Hemophilia A (HA) is an X-linked recessive blood coagulation disorder caused by a variety of abnormalities in F8 gene, resulting in the absence of impaired molecule production of factor VIII (FVIII) in the plasma. The genetic testing of the F8 gene encoding FVIII is used for confirmation of HA diagnosis, which significantly reduced serious complications of this disease and, ultimately, increased life expectancy. Methods: Sanger sequencing was performed in F8 gene exons of the suspected patients with blood coagulation-related indicators. Results: A novel F8 indel variant c.6343delC, p.Leu2115SerfsTer28 in exon 22 of the F8 gene was identified in the suspected families. The infant with this novel variant appeared the symptom of minor bleeding and oral cavity bleeding, and decreased activity of FVIII, which is consistent with that of F8 deleterious variants. The 3'D protein structural analysis of the novel variant shows a change in FVIII protein stability, which may be responsible for the pathogenesis of HA. Conclusions: A novel deleterious variant was identified in our case, which expands the F8 variants spectrum. Our result is helpful for HA diagnosis and benefits carrier detection and prenatal diagnosis. Our study also reveals that mutation screening of the F8 gene should be necessary for HA suspected patients.

Three-Decade Successive Establishment of Care for Women/Girls from Families with Haemophilia

Objective

The study aimed to report a 3-decade successive establishment of care for women/girls from families with haemophilia.

Methods

A retrospective analysis was conducted on 462 women/girls from 243 families from 1987 to 2021.

Results

Combining phenotypic analysis of coagulation factor and genotypic analysis of either linkage analysis or mutation detection confirmed the status of all obligate haemophilia carriers (A118, B19). For potential carrier, 159 proven carriers (A130, B29) and 146 noncarrier status (A126, B20) were diagnosed except 20 potential carriers (A16, B4). Only 54 prenatal diagnoses were requested resulting in normal males (n = 21), males with haemophilia A (n = 12) and females with either normal or carrier status (n = 21). Additionally, 40 women/girls with haemophilia carrier received a diagnosis of severe haemophilia A with Turner’s syndrome (n = 2) and mild haemophilia (A31, B7). The skewed X-chromosome inactivation of the nonmutant factor VIII/IX carrying X-chromosome of 8% (2/25) was found in mild haemophilia. Factor concentrate and desmopressin are prescribed for these affected women/girls. The response of women/girls with either haemophilia carrier or haemophilia was amazement with their religious beliefs and cultural acceptance.

Conclusion

Appropriate care for women/girls from families with haemophilia concerning diagnosis and management of haemophilia and carrier has been successively established.

Managing Pregnant Women with Hemophilia and von Willebrand Disease: How Do We Provide Optimum Care and Prevent Complications?

The challenge of pregnancy can be significant to the point of being life-threatening in a woman with a bleeding disorder. Additionally there can be a risk to the fetus and the neonate. A hemostatic defect can affect the course of the pregnancy, but the impact is most feared around delivery in the immediate and the extended post partum period, requiring rapid identification and prompt referral to a hematologist for assistance in management. Identifying the type of congenital bleeding disorder and knowing its inheritance pattern is crucial during counseling prior to conception and in preparation for delivery. A comprehensive approach by a specialized and experienced team in a tertiary care center with access to adequate laboratory monitoring and therapies can facilitate the process. The multidisciplinary team should include a hematologist, an obstetrician, a pediatric hematologist, an anesthesiologist, and in select cases a clinical geneticist and a maternal fetal medicine specialist. In this review article, we will detail the diagnostic path and management of pregnancy and delivery in women with some inherited bleeding disorders, in particular those affected by hemophilia A (HA), hemophilia B (HB), and von Willebrand disease (VWD).

The musculoskeletal manifestations of haemophilia: a review of the imaging findings

Haemophilia is a common hereditary cause of bleeding diathesis and the musculoskeletal system is frequently affected. Repeated episodes of haemarthrosis initiate a cascade towards haemophilic arthropathy, a disabling and deforming joint disease with both degenerative and inflammatory features, which include articular cartilage loss, bone erosions, and synovitis. Haemophilic pseudotumour and intra-muscular haematoma make up the remainder of the musculoskeletal manifestations of this systemic condition. Radiological assessment is vital in the assessment and follow-up of these haemophilic complications and MRI is the reference standard. This article summarises the radiological findings relevant to the diagnosis and monitoring of this complex patient group.

Hemostatic and thrombotic disorders in the pediatric patient

This review focuses on significant advances in the field of pediatric hemostasis and thrombosis, with a focus on published studies within the past decade. The evaluation and management of patients with excessive bleeding remain cornerstones of consultative hematology. We will describe the development of validated bleeding assessment tools relevant to pediatric practice, laboratory advances in the evaluation of von Willebrand disease, and a shift in clinical practice regarding the interpretation of normal coagulation studies in patients with significant bleeding phenotypes. There have also been critical advances in the management of hemostatic disorders. This review highlights new treatment paradigms in hemophilia and the rise of multidisciplinary medical homes for women living with bleeding disorders. Given the continued increase in the incidence of thrombosis, particularly in the hospital setting, a full call to arms against pediatric venous thromboembolism is now essential. We will describe recently completed clinical trials of direct oral anticoagulants in children and adolescents and ongoing work to elucidate the appropriate duration of therapy for children with provoked thrombosis. Recent work regarding the prevention of pediatric venous thromboembolism is highlighted, including studies of thromboprophylaxis and the development of risk prediction models for hospital-acquired thrombosis. Finally, we review advances in our understanding of thrombotic sequelae and the need for continued refinement of our evaluation tools. Despite the significant advances in pediatric hemostasis and thrombosis over the past decade, many unanswered questions remain for the next generation of investigators.

Advances in Hemophilia A Management

Hemophilia A is an inherited insufficiency of Factor VIII (FVIII), one of the critical clotting factors. The gold standard for the management of moderate-to-severe hemophilia A is prophylaxis using regular replacement therapy with clotting factor concentrates. Compared with conventional treatment, extended half-life products reduce the burden of frequent factor replacement injections. Of note, up to 30% of patients with hemophilia A receiving prophylactic factor infusions develop "inhibitors," neutralizing anti-FVIII autoantibodies. Therapeutic options for patients with hemophilia A and inhibitors include the immune tolerance induction (ie, eradication of inhibitors) and the management of acute bleeds with bypassing agents and/or emicizumab. Emicizumab is a biphasic monoclonal antibody mimicking activated FVIII, approved for patients with hemophilia A with/without inhibitors. Gene therapy is an emerging therapy for hemophilia A, essentially curing patients with hemophilia A or transforming them to a milder phenotype by establishing continuous endogenous expression of FVIII after one-time treatment.

Challenges and knowledge gaps facing hemophilia carriers today: Perspectives from patients and health care providers

Background

Hemophilia carriers experience abnormal bleeding symptoms; however, a lack of awareness about this topic coupled with additional knowledge gaps and barriers leads to suboptimal care for this population.

Objective

The primary objective was to describe the current knowledge gaps and challenges from the perspective of both hemophilia carriers and their health care providers.

Methods

We carried out a mixed methods descriptive study with two population groups between September and December 2020. The hemophilia carrier perspective was obtained through both focus groups and questionnaires, whereas the health care providers perspective obtained via questionnaire sent to the Association of Hemophilia Care Directors of Canada and the Canadian Association of Nurses in Hemophilia Care. Focus groups were analyzed using descriptive thematic analysis and quantitative survey data was also analyzed.

Results

Eleven hemophilia carriers participated along with 19 health care providers (11 physicians, eight nurses). Hemophilia carrier focus group discussions identified four areas representing major challenges or knowledge gaps: (1) negative psychosocial impacts; (2) difficulty determining symptom significance; (3) need for self‐advocacy; (4) testing concerns. Survey results from both groups were aligned with the most important topics for ongoing education identified as information on abnormal bleeding symptoms, where to seek treatment, and considerations for heavy menstrual bleeding/menstruation. The majority of both study groups believe obligate or potential carriers should have factor levels checked regardless of age if symptoms of abnormal bleeding occur or before an invasive procedure. However, hemophilia carriers were significantly more in favor of genetic testing under the age of consent than health care providers in all scenarios evaluated.

Total Hip Arthroplasty in Patients With Classic Hemophilia: A Matched Comparison of 90-Day Outcomes and 5-Year Implant Survival

BACKGROUND

Patients with classic hemophilia can develop joint hemarthroses, degenerative changes, and eventually require total hip arthroplasty (THA). Little data exist concerning THA outcomes in this population, and evidence-based guidelines specifically addressing venous thromboembolism (VTE) prophylaxis in this population are lacking.

METHODS

A retrospective study was conducted using the 2010-2020 PearlDiver MHip database. Patients undergoing primary THA were identified, and those with classic hemophilia were matched 1:10 with non-hemophilia patients based on age, gender, and Elixhauser Comorbidity Index. Ninety-day serious adverse events, minor adverse events, and any adverse events were compared with multivariate analysis. Reoperation at 5 years was assessed using Kaplan-Meier analysis.

RESULTS

Five hundred eighteen classic hemophilia THA patients were matched 1:10 with 5,193 non-hemophilia patients. On multivariate analysis, those with classic hemophilia had greater odds of aggregated any adverse events (odds ratio [OR] 1.76), serious adverse events (OR 2.30), and minor adverse events (OR 1.52) (P < .001 for each). Patients with classic hemophilia had greater odds of bleeding issues (transfusion, OR 1.98; hematoma, OR 4.23; P < .001 for both), VTE (deep vein thrombosis, OR 2.67; pulmonary embolism, OR 4.01; P < .001 for both), and acute kidney injury (OR 1.63; P = .03). Five-year implant survival was lower in hemophilia patients (91.9%) relative to matched controls (95.3%; P = .009).

CONCLUSION

Hemophilia patients undergoing THA had elevated risks of both 90-day bleeding complications (transfusion and hematoma) and VTE (deep vein thrombosis and pulmonary embolism) relative to matched controls. These findings emphasize the need to balance factor replacement and VTE prophylaxis. Although the 5-year implant survival was lower in hemophilia patients, this represented a difference of 3.4% at 5 years, suggesting that THA remains effective in this cohort.

Investigation of the Bleeding Tendency in Sudanese Female Carriers of Hemophilia B

Background. Hemophilia (HB) is an X-linked, recessive bleeding disorder characterized by the deficiency or absence of the coagulation factor IX. Usually, females are carriers of the trait, while males are affected. FIX deficiency leads to uncontrollable bleeding events, and the severity is dependent on the levels of the clotting factor. The objective of this research was to measure the prevalence of bleeding tendency in Sudanese carriers of HB. Materials and Methods. In this cross-sectional study, 88 Sudanese carriers of HB participated. The activated partial thromboplastin time test (APTT) and FIX test were performed for each carrier. The frequencies of DNA polymorphism and FIX-linked restriction fragments BamHI, HhaI, and MnII were also assessed. The study was conducted in Khartoum, Sudan, during the period from 2015 to 2017. Results. The study showed that 55 (62.5%) HB carriers were from the Laban village in the White Nile State, and all of them were members of the Shinkheb tribe. The mean age of the study population was 26.3 years. Among the carriers, 57 (64.7%) had abnormal coagulation profiles. The mean value of the APTT level among carriers was significantly increased ( $P$ value: 0.000), while the mean concentration of the FIX levels among the carriers was significantly decreased ( $P$ value: 0.000). The study also showed a negative correlation between PTT and F assay with $P$ value of 0.000 and $R$ value of 0.578. Conclusion. The APTT is high in most carriers and the FIX assay level is low in most carriers. Most carriers had no symptoms and were not bleeding. The Shinkheb tribe is the most ethnic tribe carrying HB (62.5%). HhaII is more informative for carrier detection than others, but it is of significant value if both (MnII and HhaII) were performed in parallel. In Sudanese, BamHI was informative but MnII and HhaII were best in the mutation detection and for prenatal diagnosis.

Health issues in women and girls affected by haemophilia with a focus on nomenclature, heavy menstrual bleeding, and musculoskeletal issues

Introduction

Women and girls affected by haemophilia, including haemophilia carriers (WGH) are at risk of bleeding symptoms that may go unrecognized, including heavy menstrual bleeding (HMB) and musculoskeletal bleeding. Terminology continues to evolve.

Aim

To describe the current recommendations for nomenclature surrounding WGH, and the current understanding of HMB, iron deficiency, and musculoskeletal complaints in these patients.

Methods

Literature was reviewed and summarized.

Results

With regards to nomenclature, women with factor levels less than 50% should be classified as having haemophilia, while carriers with normal levels should be characterized accordingly to symptomatology. HMB and resultant iron deficiency are common among WGH, have a multitude of downstream effects, and maybe overlooked due to stigma around menstruation. Musculoskeletal bleeding and resultant joint changes are increasingly recognized in this population but do not necessarily correlate with factor levels.

Conclusion

Although progress has been made in the care of WGH, much work remains to further improve their care.

Management and outcomes of mild hemophiliacs and hemophilia carriers during pregnancy and peripartum period: a hemophilia treatment center experience in the United States

BACKGROUND

Pregnancy, peripartum management, and outcomes of mild hemophiliacs and hemophilia carriers in the United States are not well established.

AIM

To describe the management and outcomes of mild hemophiliacs and hemophilia carriers during assisted conception, pregnancy, peripartum and post-partum period at our hemophilia treatment center (HTC).

METHODS

Retrospective review of electronic medical records of pregnant women with mild hemophilia A or B (Factor VIII [FVIII] or Factor IX [FIX] level <0.4 IU/mL) and hemophilia A and B carriers followed at our HTC from January 2008 to October 2020. Demographics, the reason for diagnosis, FVIII and FIX levels at baseline and third trimester, bleeding phenotype and genotype were obtained. Method of conception, factor replacement, iron supplementation, mode of delivery, type of anesthesia, peripartum complications, and offspring outcomes was recorded.

RESULTS

There was a total of 18 pregnancies in 12 women (2 with mild hemophilia A, 2 mild hemophilia B, 6 hemophilia A carriers, and 2 hemophilia B carriers). Eleven pregnancies (61%) were conceived naturally and 7 (39%) via in-vitro fertilization (IVF). Eight (44.4%) and 10 (55.6%) pregnancies were vaginal and C-section deliveries, respectively. Neuraxial anesthesia was administered in 17 (94.4%) deliveries without complications. Four pregnancies (22.2%) had bleeding complications, 2 of which were post-partum hemorrhages not requiring transfusion.

CONCLUSION

In our case series of pregnant hemophilia carriers and mild hemophiliacs, successful outcomes were achieved with a carefully detailed multidisciplinary-driven approach.

Factor IX(a) inhibitors: an updated patent review (2003-present)

INTRODUCTION

Anticoagulation with no bleeding complications is the current objective of drug discovery programs in the area of treating and/or preventing thromboembolism. Despite the promises of therapeutics targeting factors XI(a) and XII(a), none has been approved thus far. Clinically used thrombin- and/or factor Xa-based anticoagulants continue to be associated with a significant bleeding risk which limits their safe use in a broad range of thrombotic patients. Research findings in animals and humans indicate that it is possible to target factor IX(a) (FIX(a)) to achieve anticoagulation with a limited risk of bleeding.

AREAS COVERED

A review of patents literature has retrieved >35 patents on the development of molecules targeting FIX(a) since 2003. Small molecules, antibodies, and aptamers have been developed to target FIX(a) to potentially promote effective and safer anticoagulation. Most of these agents are in the pre-clinical development phase and few have been tested in clinical trials.

EXPERT OPINION

FIX(a) system is being considered to develop new anticoagulants with fewer bleeding complications. Our survey indicates that the number of FIX(a)-targeting agents is mediocre. The agents under development are diverse. Although additional development is essential, moving one or more of these agents to the clinic will facilitate achieving better clinical outcomes.

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.

Determining common variants in patients with haemophilia A in South Vietnam and screening female carriers in their family members

AIMS

The aim of this study was to determine common variants in F8, including intron 22 inversion (Inv22), intron 1 inversion (Inv1) and point mutations, the transmission of these variants between patients with haemophilia A (HA) and their family members.

METHODS

Genetic analysis was conducted in 71 patients who were clinically diagnosed with HA and 152 related female members in South Vietnam by a combination of inversion PCR (I-PCR), multiplex PCR and direct sequencing.

RESULTS

Variants in F8, including Inv22, point mutations (with 37 genotypes) and two novel variants, occupied 60 patients with HA. Among severe patients, the rate of Inv22 was 44%. Missense was the common point mutation of over 50% in patients with moderate HA and mild HA. Inv1 was absent in all patients. F8 variants were also found in 119 female carriers (FCs) (78.3%) from families related to patients with HA. There were 56 mothers (93.3%) carrying F8 variants and passing the same variants to their sons.

CONCLUSIONS

These findings were the first to provide important information about the presence of Inv22 and point mutation in Vietnamese patients with HA, the mothers and their female family members. It demonstrated that genetic diagnosis and counselling for HA carriers were essential factors for future improvements in comprehensive and equitable healthcare polices for patients with HA and FCs in Vietnam.

Descriptive analysis of bleeding symptoms in haemophilia carriers enrolled in the ATHNdataset

BACKGROUND

Several studies have reported that haemophilia carriers have a bleeding tendency independent of factor activity. However, investigations have been fraught with methodological concerns. The ATHNdataset houses the largest data set of haemophilia carriers in the world. We undertook an analysis of haemophilia carriers in this data set using methodologies that characterize bleeding symptoms in carriers.

AIM

Determine the proportion of haemophilia carriers who have a normal bleeding score (BLS) and factors that affect the BLS.

METHODS

The ATHNdataset was queried for haemophilia carriers with a documented BLS. Collected data included demographics, ISTH-BAT score, factor activity level, type of haemophilia (A or B), genotype and geographic residence.

RESULTS

Nine hundred twenty-two haemophilia carriers in the ATHNdataset reported a BLS. When adjusted for age, 74% reported a normal score. Logistic regression identified age, factor activity level, ethnicity and region of residence as risk factors for an abnormal score.

CONCLUSIONS

The majority of haemophilia carriers (74%) in the ATHNdataset had a normal BLS, including the majority (59%) with factor activity levels < 40 IU/dl. Conversely, 24% of haemophilia carriers with a factor activity level > 40 IU/dl reported an abnormal BLS. These results are consistent with previous studies of haemophilia carriers. Additional investigation is needed to determine why a majority of haemophilia carriers with low factor activity levels report normal BLSs while a significant minority of haemophilia carriers with normal activity levels report abnormal BLSs.

Women and girls with haemophilia receiving care at specialized haemophilia treatment centres in the United States

INTRODUCTION

Females may have haemophilia with the same factor VIII (FVIII) or factor IX (FIX) levels as affected males. Characterization of females with haemophilia would be useful for health care planning to meet their unique needs. Federally-funded haemophilia treatment centres (HTCs) in the United States contribute data on all individuals with bleeding disorders receiving care to the Population Profile (HTC PP) component of the Community Counts Public Health Surveillance of Bleeding Disorders project.

AIMS

To estimate the number of females with haemophilia receiving care at HTCs in the United States and compare their characteristics with those of males with haemophilia.

METHODS

HTC PP data collected on people receiving care at an HTC from January 2012 through September 2020 with haemophilia A and B were evaluated by sex for demographic and clinical characteristics.

RESULTS

A factor level < 40% was reported for 23,196 males (97.8%) and 1667 females (47.6%) attending HTCs; 51 (.48%) severe, 79 (1.4%) moderate, and 1537 (17.9%) mild haemophilia patients were female. Females were older, more often White, and less often non-Hispanic than males. Females were less likely to have history of HIV or HCV infection, even among those with severe disease, but twice as likely to have infection status unknown. Females with mild haemophilia were more often uninsured than males.

CONCLUSIONS

Females with severe or moderate haemophilia are uncommon, even in specialized care centres; however, almost one in five patients with mild haemophilia was female, indicating needs for specialized care based on factor level and history for affected females.

Viscoelastic Hemostatic Assays for Postpartum Hemorrhage

This article discusses the importance and effectiveness of viscoelastic hemostatic assays (VHAs) in assessing hemostatic competence and guiding blood component therapy (BCT) in patients with postpartum hemorrhage (PPH). In recent years, VHAs such as thromboelastography and rotational thromboelastometry have increasingly been used to guide BCT, hemostatic adjunctive therapy and prohemostatic agents in PPH. The three pillars of identifying hemostatic competence include clinical observation, common coagulation tests, and VHAs. VHAs are advantageous because they assess the cumulative contribution of all components of the blood throughout the entire formation of a clot, have fast turnaround times, and are point-of-care tests that can be followed serially. Despite these advantages, VHAs are underused due to poor understanding of correct technique and result interpretation, a paucity of widespread standardization, and a lack of large clinical trials. These VHAs can also be used in cases of uterine atony, preeclampsia, acute fatty liver of pregnancy, amniotic fluid embolism, placental abruption, genital tract trauma, surgical trauma, and inherited and prepartum acquired coagulopathies. There exists an immediate need for a point-of-care test that can equip obstetricians with rapid results on developing coagulopathic states. The use of VHAs in predicting and treating PPH, although in an incipient state, can fulfill this need.

A qualitative study on the experiences of haemophilia carriers before, during and after pregnancy

INTRODUCTION

Haemophilia carriers (HCs) face considerable haemostatic and psychological challenges during reproduction.

AIM

To explore the perspectives of HCs on healthcare in the current standard of haemophilia treatment during all reproductive phases: preconception, pregnancy, childbirth and the postpartum period. In addition, we examined the psychological impact of haemophilia during these phases.

MATERIAL AND METHODS

Focus group discussions (FGDs) and semi-structured interviews were conducted with HCs in January/February 2020 until data saturation was reached. All sessions were recorded, transcribed verbatim and analysed by two independent researchers through thematic content analysis using MAXQDA® software. The results were then discussed within the research team until consensus was reached. The constructed themes were shared with and reviewed by the HCs.

RESULTS

Fifteen HCs were included in three FGDs and four interviews. Five central themes were constructed: (1) communication by healthcare professionals, (2) lack of knowledge, (3) feeling insecure, (4) autonomy and (5) family experiences with haemophilia. Desired improvements in care mainly concerned counselling during preconception and pregnancy. This included timely access to comprehensive information during each consecutive phase, acceptance of HCs' choices by healthcare providers and healthcare tailored to the HC's family experience with haemophilia.

CONCLUSIONS

In recent years, haemophilia treatment has seen major advances, which could impact general and reproductive care for HCs. HCs indicated that reproductive care would benefit from a more personal and informative approach. Healthcare professionals could use these insights to adapt their consultations to meet the needs of these women when they are preparing for having children.

Investigating Optimal Autologous Cellular Platforms for Prenatal or Perinatal Factor VIII Delivery to Treat Hemophilia A

Patients with the severe form of hemophilia A (HA) present with a severe phenotype, and can suffer from life-threatening, spontaneous hemorrhaging. While prophylactic FVIII infusions have revolutionized the clinical management of HA, this treatment is short-lived, expensive, and it is not available to many A patients worldwide. In the present study, we evaluated a panel of readily available cell types for their suitability as cellular vehicles to deliver long-lasting FVIII replacement following transduction with a retroviral vector encoding a B domain-deleted human F8 transgene. Given the immune hurdles that currently plague factor replacement therapy, we focused our investigation on cell types that we deemed to be most relevant to either prenatal or very early postnatal treatment and that could, ideally, be autologously derived. Our findings identify several promising candidates for use as cell-based FVIII delivery vehicles and lay the groundwork for future mechanistic studies to delineate bottlenecks to efficient production and secretion of FVIII following genetic-modification.

European principles of care for women and girls with inherited bleeding disorders

INTRODUCTION

Despite increasing awareness of issues faced by women and girls with inherited BDs (WGBD), standards of care are lacking, with disparities in diagnosis and treatment for WGBD across Europe. We aimed to develop practical principles of care (PoC) to promote standardization of care for WGBD within European Haemophilia Treatment and Comprehensive Care Centres (HTC/CCCs).

METHODS

The co-creation process, supported by the European Association for Haemophilia and Allied Disorders, consisted of four multidisciplinary meetings with health care providers (HCPs) experienced in WGBD care, and European Haemophilia Consortium representatives, combined with broad patient and HCP consultations in the European haemophilia community. Relevant medical societies outside Europe were contacted for confirmation.

RESULTS

We developed ten PoC for WGBD, stressing the importance and benefits of a centralized, multidisciplinary, comprehensive, family-centred approach to support and manage WGBD during all life stages. These PoC emphasise the right to equitable access and quality of care for all people with BDs, irrespective of gender. Multiple medical societies outside Europe also confirmed their support for endorsement.

CONCLUSIONS

Ten PoC for WGBD evolved from an iterative process among stakeholders, supported by relevant medical societies worldwide. These PoC can serve as a benchmark for diagnosis and comprehensive multidisciplinary management of WGBD, and improve awareness of their unique challenges. They offer a framework to guide HTC/CCCs in providing equitable care for all WGBD, both in their own services and in other healthcare settings. Implementation of these principles aims to positively impact the health, wellbeing and quality of life for WGBD.

A new hemophilia carrier nomenclature to define hemophilia in women and girls: Communication from the SSC of the ISTH

Hemophilia A and B predominantly attracts clinical attention in males due to X-linked inheritance, introducing a bias toward female carriers to be asymptomatic. This common misconception is contradicted by an increasing body of evidence with consistent reporting on an increased bleeding tendency in hemophilia carriers (HCs), including those with normal factor VIII/IX (FVIII/IX) levels. The term HC can hamper diagnosis, clinical care, and research. Therefore, a new nomenclature has been defined based on an open iterative process involving hemophilia experts, patients, and the International Society on Thrombosis and Haemostasis (ISTH) community. The resulting nomenclature accounts for personal bleeding history and baseline plasma FVIII/IX level. It distinguishes five clinically relevant HC categories: women/girls with mild, moderate, or severe hemophilia (FVIII/IX >0.05 and <0.40 IU/ml, 0.01-0.05 IU/ml, and <0.01 IU/ml, respectively), symptomatic and asymptomatic HC (FVIII/IX ≥0.40 IU/ml with and without a bleeding phenotype, respectively). This new nomenclature is aimed at improving diagnosis and management and applying uniform terminologies for clinical research.

Regulation and importance of factor VIII levels in hemophilia A carriers

PURPOSE OF REVIEW

To summarize the recent literature related to female hemophilia A carriers with respect to prevalence in the population, the impact of baseline factor VIII levels and other influences on bleeding phenotype, and clinical management needs.

RECENT FINDINGS

Many female hemophilia A carriers are at risk for abnormal bleeding, yet they are underrecognized by healthcare providers and their bleeding symptoms are underreported. Low FVIII levels are consistently associated with clinically significant bleeding and correlate well with skewed X chromosome inactivation (XCI). Most interestingly, bleeding tendency is also observed in some hemophilia A carriers with normal factor VIII levels and requires further investigation. Well controlled studies investigating peripartum and periprocedural FVIII levels and adequate hemostatic treatment are necessary to inform management guidelines.

SUMMARY

Prevalence and bleeding tendency of hemophilia A carriers remain underreported, despite a significant proportion having low FVIII levels. Skewed XCI may explain low FVIII but does not explain the bleeding risk encountered in a larger proportion of hemophilia A carriers with random XCI and borderline/normal FVIII.

Haemophilia Carriers Experience Study (CARES): A mixed method exploration into the experience of women who are carriers of Haemophilia

INTRODUCTION

Haemophilia research has traditionally focused on patients diagnosed with haemophilia and although research priorities are rapidly changing, there is still a lot more we need to understand about the experiences and psychosocial issues facing women who are diagnosed as carriers of haemophilia (Haemophilia, https://doi.org/10.1111/hae.14043). One study noted that the understanding of carriers' experience of bleeding by healthcare professionals is limited and that many women have had negative experiences of healthcare (Haemophilia, 17, 2011, 237). The carrier population does not typically receive much support for themselves as individuals as they are often not registered at Haemophilia Centres in their own right.

AIM

This study aimed to look at the emotional wellbeing of carriers in more detail.

METHOD

This was initially investigated through the use of focus groups and individual interviews with 16 participants (Stage 1) and then widening the study using an online questionnaire battery developed from the themes identified from these interviews (Stage 2). The questionnaire battery was completed by 226 participants.

RESULTS

Descriptive statistics are reported on the endorsement of themes identified in Stage 1 and around participants' experiences of their carriership and healthcare. Results demonstrated that the participants have had a number of difficulties with accessing helpful information and support during key times in their lives, for example, at diagnosis and when deciding whether to start a family. They also showed that although participants endorsing a higher number of bleeding symptoms scored statistically significantly higher in measures of depression, anxiety and negative affect, this difference was not clinically significant.

CONCLUSION

These results lend support to the growing evidence base that women who are carriers of haemophilia have a distinct set of (currently unmet) needs that need assessing and treating.

Bleeding Post Constriction Ring Release Surgery Causing Lower Limb Ischemia in an Infant with Undetected Hemophilia B

Bleeding in the immediate postoperative period causing compromised limb circulation is an alarming complication. It is known to occur in coagulation disorders like hemophilia. When such complications happen in a child with no previous history of bleeding problems, one has to have a low threshold for suspecting a coagulation disorder. Repeated diffuse bleeding in the whole of the surgical wound with no specific bleeders must raise the suspicion and appropriate laboratory tests must immediately be ordered. Bleeding in coagulation disorders can stop only with supplementation of the appropriate missing clotting factor. Early diagnosis is important to avoid excess morbidity. We are reporting a 6-month-old child who underwent surgery for constriction ring syndrome in the limbs with Z-plasty and developed impending limb ischemia due to bleeding in the immediate postoperative period. The article emphasizes the need to think of the possibility while encountering recurrent bleeding in the postoperative period.