Both hemophilia health care providers and hemophilia a carriers report that carriers have excessive bleeding

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.

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.

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.

Clinical Application of Factor VIII:C to VWF:Ag Ratio for the Screening of Haemophilia A Carriers

Analyses of factor VIII procoagulant activity (FVIII:C) and the FVIII:C to VWF:Ag ratio (FVIII:C/VWF:Ag ratio) have been investigated as screening bioassays to detect haemophilia carriers. This study aimed to determine the validity of the FVIII:C/VWF:Ag ratio and FVIII:C analyses as screening tests. We reviewed the medical records of 137 genetically confirmed, proband haemophilia A patients and 179 of their familial females who had undergone carrier testing. The collected data included the severity and mutation type of F8 gene from probands and age, ABO blood type, FVIII:C, VWF:Ag, and the result of targeted gene analysis in females. We diagnosed 110 females as carriers, and their FVIII:C and FVIII:C/VWF:Ag ratio were lower than those in 69 non-carriers (FVIII:C: 59.3 IU/dL vs. 106.1 IU/dL, p = 0.000; FVIII:C/VWF:Ag ratio: 0.62 vs. 1.08, p = 0.000). In receiver operating characteristic analysis, the areas under the curve (AUC) of the FVIII:C/VWF:Ag ratio and FVIII:C were 0.936 and 0.876, respectively. The cut-off value of FVIII:C/VWF:Ag ratio (0.81) at the maximum Youden J index provided a sensitivity of 82.8% and specificity of 96.6%. The cut-off value of FVIII:C (83.8 IU/dL) showed a sensitivity of 81.8% and specificity of 79.7%. Considering the AUC, the FVIII:C/VWF:Ag ratio is a good screening test to detect haemophilia A carriers, as evidenced by its specificity of 96.6%; however, it may also induce false-negative results.

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.

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.

Identified unmet needs and proposed solutions in mild-to-moderate haemophilia: A summary of opinions from a roundtable of haemophilia experts

INTRODUCTION

The experiences of patients with mild-to-moderate haemophilia differ from those of patients with severe haemophilia or those without a bleeding disorder and include a challenging diagnosis and variability in bleeding symptoms and treatment needs. In addition, there is a significant lack of data on mild-to-moderate haemophilia, and many unmet needs remain to be identified and addressed in this group of patients.

METHODS

Challenges for these patients, including women with haemophilia, were identified during a roundtable meeting attended by a group of US-based experts including healthcare professionals (e.g., physicians, nurses, and physical therapists) and patients who live with a bleeding disorder.

RESULTS

Identified unmet needs included a lack of proper education on the management of their disorder and prompt treatment of bleeds, absenteeism from school and work, and challenges with personal relationships. Initiatives to assist with alleviating these unmet needs were proposed and include suggestions for healthcare professionals, haemophilia treatment centres (HTCs) and national and local organizations within the bleeding disorders community. These included HTC and community engagement programmes for patients with mild-to-moderate haemophilia, revised transition guidelines for these patients as they approach adulthood and revised diagnostic classification of mild and moderate haemophilia. Challenges unique to women with haemophilia and ways to address these issues were also discussed.

CONCLUSION

This paper summarizes the challenges, initiatives and suggestions that were identified by the haemophilia experts during the roundtable meeting.

Impact of haemophilia on patients with mild-to-moderate disease: Results from the P-FiQ and B-HERO-S studies

INTRODUCTION

Epidemiologic studies suggest that joint bleeding occurs in patients with mild-to-moderate haemophilia, including women and girls. However, most previous studies on the impacts of haemophilia focus on men with severe disease.

AIM

To identify unmet needs in men and women with mild-to-moderate haemophilia.

METHODS

The Pain, Functional Impairment, and Quality of Life (P-FiQ) study assessed the impact of pain on functional impairment and health-related quality of life in men with haemophilia A or B of any severity. The Bridging Hemophilia B Experiences, Results and Opportunities Into Solutions (B-HERO-S) study evaluated the psychosocial needs of adults and children with haemophilia B of any severity, including women and girls. Both studies employed patient-reported outcome measures.

RESULTS

In the P-FiQ study, 16% (62/381) of participants had mild and 13% (50/381) had moderate haemophilia. In the B-HERO-S study, 29% (86/299) of adult participants were female, 25% (74/299) had mild haemophilia, and 63% (189/299) had moderate haemophilia. In addition, 63% (46/74) of patients with mild and 86% (162/189) of patients with moderate haemophilia routinely infused factor products to prevent bleeding. Patients reported difficulty gaining access to factor products (54%; 142/263) and a haemophilia treatment centre (17%; 44/263). During the P-FiQ study, 78% (48/62) of patients with mild and 87% (44/50) with moderate haemophilia described problems with pain on the Brief Pain Inventory. Patients also reported issues with anxiety, depression and relationships.

CONCLUSIONS

Mild-to-moderate haemophilia has physical and psychosocial impacts on patients. We offer some solutions to help alleviate these impacts and resolve unmet needs.

Women and girls with haemophilia and bleeding tendencies: Outcomes related to menstruation, pregnancy, surgery and other bleeding episodes from a retrospective chart review

Introduction

Women or girls with haemophilia (WGH) represent a group of female symptomatic carriers who experience bleeding events more frequently than non‐carriers. Bleeding events include spontaneous/traumatic bleeds and prolonged bleeding related to surgery, menstruation and pregnancy. Challenges for the treatment of WGH include lack of screening, diagnosis and treatment guidelines.

Aim

Evaluate clinical characteristics, haemostasis management and clinical outcomes regarding menstruation, childbirth, dental procedures, surgeries and other bleeding events in WGH.

Methods

A retrospective, non‐interventional review of medical records from WGH among three haemophilia treatment centres (HTCs) was conducted in the United States (2012–2018). Patients with ≥2 visits to the HTC and who had undergone intervention for haemostasis management with the outcome documented were included. Descriptive statistics were used.

Results

Of 47 women and girls included in the chart review (37 with factor VIII deficiency, 10 with factor IX deficiency), median age at diagnosis was 22.6 years. Approximately 79% (n = 37) were diagnosed with mild haemophilia. Events of interest were primarily managed by factor concentrates or antifibrinolytics. Most treatment approaches were successful across clinical scenarios, except for heavy menstrual bleeding being insufficiently controlled in 8 (57%) of the 14 patients who experienced it.

Conclusions

Bleeding events in WGH, such as excessive and prolonged bleeding during menstruation, demonstrate a unique burden and require specific medical intervention. These results highlight the importance of assessing the need for haemostasis management in WGH and may contribute to future prospective study designs.

X Chromosome inactivation: a modifier of factor VIII and IX plasma levels and bleeding phenotype in Haemophilia carriers

Haemophilia A and B are X-linked hemorrhagic disorders caused by gene variants in the F8 and F9 genes. Due to recessive inheritance, males are affected, while female carriers are usually asymptomatic with a wide range of factor VIII (FVIII) or IX (FIX) levels. Bleeding tendency in female carriers is extremely variable and may be associated with low clotting factor levels. This could be explained by F8 or F9 genetic variations, numerical or structural X chromosomal anomalies, or epigenetic variations such as irregular X chromosome inactivation (XCI). The aim of the study was to determine whether low FVIII or FIX coagulant activity in haemophilia carriers could be related to XCI and bleeding symptoms. HUMARA assay was performed on 73 symptomatic carriers with low clotting activity ≤50 IU/dL. Bleeding Assessment Tool (BAT) from the International Society on Thrombosis and Haemostasis (ISTH) was used to describe symptoms in the cohort of carriers. In 97% of haemophilia carriers, a specific gene variant in heterozygous state was found, which alone could not justify their low FVIII or FIX levels (≤50 IU/dL). A statistical association between XCI pattern and FVIII and FIX levels was observed. Moreover, female carriers with low coagulant activity (≤20 IU/dL) and high degree of XCI ( ≥ 80:20) had a higher ISTH-BAT score than the carriers with the opposite conditions (>20 IU/dL and <80:20). In our cohort of haemophilia carriers, XCI was significantly skewed, which may contribute to the low expression of clotting factor levels and bleeding symptoms.

Hemophilia A in Females: Considerations for Clinical Management

Approximately 50% of female carriers of hemophilia A have factor VIII (FVIII) levels below 0.5 IU/dL and may be categorized as having mild hemophilia. Females with hemophilia may go undiagnosed for years because the most common symptoms - menorrhagia and bleeding after childbirth - also occur in females without hemophilia. Females with hemophilia can exhibit increased bleeding tendencies despite current guidelines of expected, adequate FVIII levels. The cases described illustrate the clinical variability and presentation of hemophilia in females and highlight the importance of a timely diagnosis, effective management, and monitoring. Prophylactic factor replacement therapy is recommended in females with hemophilia, particularly those with joint disease or gynecologic complications. Affected individuals should receive infusion training and education on treatment options, physical activities, the importance of treatment adherence, and recognizing bleeding symptoms warranting treatment. Further study is needed to increase awareness of hemophilia in females and reassess current guidelines for their management and monitoring.

Bone health in symptomatic carriers of haemophilia A: a protocol for a multicentre prospective matched-cohort study

INTRODUCTION

Haemophilia A is an X linked inherited bleeding disorder, caused by a decrease in coagulation factor VIII. Persons with haemophilia experience repeated musculoskeletal bleeding, which can lead to decreased range of motion, irreversible joint damage, low bone mineral density (BMD), and are at greater risk for osteoporosis. Women heterozygous for this mutation, also known as haemophilia A carriers, can have bleeding symptoms and even experience joint bleeding evidenced by radiological soft tissue and osteochondral changes. The prevalence of low BMD as a risk factor for osteoporosis has never been evaluated in carriers of haemophilia, and given the recent findings which suggest subclinical musculoskeletal bleeding in carrier women, we hypothesise that they too are at risk of impaired bone health.

METHODS AND ANALYSIS

This is a national multicentre prospective matched-cohort study to compare BMD T-scores among symptomatic haemophilia A carriers, 50 years of age or older, with age-matched and body mass index-matched non-carriers (1:1). A total of 40 symptomatic carriers and 40 matched non-carriers will be recruited from St. Michael's Hospital, Kingston General Hospital in Ontario, Canada and Foothills Medical Centre in Alberta, Canada. Multivariable linear regression models will be used to estimate the effect of haemophilia carriership on BMD T-scores, adjusting for age, body mass index and other relevant covariates.

ETHICS AND DISSEMINATION

The protocol was designed and will be conducted in compliance with applicable laws, rules and regulations. Research ethics approval was obtained from St. Michael's Hospital, Foothills Medical Centre, and Kingston General Hospital. Findings will be presented at international venues such as the American Society of Haematology and the World Federation of Haemophilia World Congress. The authors of this study will seek publication in journals such as Blood, Journal of Thrombosis and Haemostasis, American Journal ofHematology and British Journal ofHaematology.

The national blueprint for pregnancy/birth longitudinal cohorts to study factor VIII immunogenicity: NHLBI State of the Science (SOS) Workshop on factor VIII inhibitors

INTRODUCTION

Patients with haemophilia can develop inhibitors to exogenous coagulation factors. Some patients are tolerant to factor, while those who develop inhibitors do so early in life. Genetics and environmental factors are known to contribute to inhibitor risk. However, it is not yet possible to predict inhibitor formation or treatment responsiveness in individuals. We hypothesize that factors in the antenatal/neonatal period inform inhibitor risk development.

AIM

To consider the design of longitudinal studies beginning in the antenatal/neonatal period and the use of new technologies to better understand haemophilia inhibitors.

METHODS

A working group was formed for the NHLBI State of the Science Workshop: Factor VIII Inhibitors: Generating a National Blueprint for Future Research to solicit input from the US haemophilia community and international collaborators to consider design of pregnancy/birth longitudinal cohorts that leverage -omics, existing phenotypic data, and in silico modelling to study inhibitors.

RESULTS

An antenatal/neonatal longitudinal cohort should begin with enrolment of pregnant genetic carriers of haemophilia and span the at-risk period for inhibitor development in the child. Data and samples from the mother, placenta, neonate and young child can be obtained that are amenable to existing assays, genomics and other -omics studies. Data can inform in silico prediction and mathematical models.

CONCLUSION

A longitudinal study beginning before birth offers the unique opportunity to study factors that influence inhibitor development prior to exposure. Advances in -omics and computational biology can study complex phenotypes in this rare disease. This study could be accomplished through interdisciplinary efforts and patient community engagement.

Barriers and challenges faced by women with congenital bleeding disorders in Europe: Results of a patient survey conducted by the European Haemophilia Consortium

INTRODUCTION

Historically, issues faced by women with bleeding disorders (WBD) have been underestimated. While advances in genetic testing have resulted in improvements, significant challenges remain in the initial recognition of abnormal bleeding and referral of WBD.

METHODS

The European Haemophilia Consortium (EHC) developed a questionnaire for WBD to provide insights into the barriers and challenges faced by WBD in Europe.

RESULTS

In total, 709 WBD responded to the survey from 32 countries, predominantly from western European countries (94%). A delay in ascertaining the diagnosis of a congenital bleeding disorders (CBD) remains, with a median age at diagnosis of 16 years. The presence of family history is strongly associated with a lower median age at diagnosis of 6 years. WBD reported significant disease impact on their day-to-day life, most evident for the rarer CBD. The bleeding symptom of biggest impact on daily life is heavy menstrual bleeding (HMB), reported by 55% of women. Importantly, 25% of WBD reports that their condition severely impacted their decision to have or has prevented them from having children. Respondents registered with Haemophilia Treatment Centres (HTC) are 2.2 times more likely to receive treatment compared to WBD in other hospital services.

CONCLUSION

Improved education for both patients and healthcare providers is essential to improve time to diagnosis, access to treatment and psychosocial supports for WBD in Europe.

Diagnosis and care of patients with mild haemophilia: practical recommendations for clinical management

Mild haemophilia is defined by factor levels between 0.05 and 0.40 IU/mL and is characterised by traumatic bleeds. Major issues associated with mild haemophilia are that it may not present for many years after birth, and that awareness, even within families, may be low. Methodological problems exist in diagnosis, such as inconsistencies in results obtained from different assays used to measure factor levels in mild haemophilia. Advances in genetic testing provide insight into diagnosis as well as the likelihood of inhibitor development, which is not uncommon in patients with mild or moderate haemophilia and can increase morbidity. The management of patients with mild haemophilia is a challenge. This review includes suggestions around formulating treatment plans for these patients, encompassing the full spectrum from clinical care of the newly diagnosed neonate to that of the ageing patient with multiple comorbidities. Management strategies consider not only the vast differences in these patients' needs, but also risks of inhibitor development and approaches to optimally engage patients.

Evaluation of the utility of the ISTH-BAT in haemophilia carriers: a multinational study

INTRODUCTION

There has been increasing recognition in recent years that female carriers of haemophilia manifest abnormal bleeding; however, data on the use of bleeding assessment tools in this population are lacking.

AIM

Our objective was to validate the ISTH-BAT in haemophilia carriers to describe bleeding symptoms and allow for comparisons with factor levels and other patient groups.

METHODS

This was a prospective, observational, cross-sectional study performed by members of Global Emerging HEmostasis Panel (GEHEP). Unselected consecutive haemophilia carriers were recruited and a CRF and the ISTH-BAT were completed by study personnel.

RESULTS

A total of 168 haemophilia carriers were enrolled: 155 haemophilia A and 13 haemophilia B. The mean age was 40 years (range: 20-82). Carriers had higher mean bleeding scores (BS) compared with age-matched controls (n = 46; 5.7 vs. 1.43; P < 0.0001) and Type 3 VWD OC (n = 32; 3.0; P = 0.009), but lower BS compared with women with Type 1 VWD (n = 83; 8.7; P < 0.0001). Fifteen carriers reported haemarthrosis, and of those six had normal FVIII/FIX levels. There was a significant but weak negative correlation between BS and factor level (Spearman's r²  = -0.36, P < 0.001).

CONCLUSION

Our results show that haemophilia carriers experience abnormal bleeding, including haemarthrosis. Overall, BS in women with Type 1 VWD > haemophilia carriers > Type 3 VWD OC > controls. Understanding the performance of the ISTH-BAT in this population is a critical step in future research aimed at investigating the underlying pathophysiology of abnormal bleeding, with the ultimate goal of optimizing treatment.

A diagnostic approach to mild bleeding disorders

Mild inherited bleeding disorders are relatively common in the general population. Despite recent advances in diagnostic approaches, mild inherited bleeding disorders still pose a significant diagnostic challenge. Hemorrhagic diathesis can be caused by disorders in primary hemostasis (von Willebrand disease, inherited platelet function disorders), secondary hemostasis (hemophilia A and B, other (rare) coagulant factor deficiencies) and fibrinolysis, and in connective tissue or vascular formation. This review summarizes the currently available diagnostic methods for mild bleeding disorders and their pitfalls, from structured patient history to highly specialized laboratory diagnosis. A comprehensive framework for a diagnostic approach to mild inherited bleeding disorders is proposed.

Evaluation of factor VIII polymorphic short tandem repeat markers in linkage analysis for carrier diagnosis of hemophilia A

Hemophilia A (HA) is the most common inherited X-linked recessive bleeding disorder caused by heterogeneous mutations in the factor VIII gene (FVIII). Diagnosis of the carrier is critical for preventing the birth of children affected by this coagulation disorder, which ultimately facilitates its management. Due to the heterogeneous nature of mutations, the large inversions and the complexity of the FVIII gene, direct recognition of the disease-associated mutation in HA is complex. Indirect linkage analysis using highly informative heterozygous polymorphic markers is an alternative method for determining the co-segregation of the mutant gene within a family for carrier detection of HA. The aim of the present study was to perform carrier diagnosis in a family with HA. Rapid multifluorescent polymerase chain reaction (PCR) was performed with six extragenic short tandem repeats (STRs), DXS1073, DXS15, DXS8091, DXS1227, DXS991, DXS993 and one intragenic marker, STR22 for linkage analysis in the HA family. All the STR markers employed in the present study were informative for linkages of pathogenic and healthy haplotypes among family members, particularly STR22, DXS1073 and DXS15. The STR marker, STR22, is within the FVIII gene while the DXS1073 and DXS15 markers are very close to the FVIII gene, where the chances of recombination are comparatively low, and provided the most accurate interpretation analysis, indicating that the proband's sister may have been the HA carrier. Rapid multifluorescent PCR using STR markers and linkage analysis was identified to be a simple method for performing HA carrier diagnosis.

A cross-sectional study of bleeding phenotype in haemophilia A carriers

Haemophilia A carriers have historically been thought to exhibit normal haemostasis. However, recent data demonstrates that, despite normal factor VIII (FVIII), haemophilia A carriers demonstrate an increased bleeding tendency. We tested the hypothesis that obligate haemophilia carriers exhibit an increase in clinically relevant bleeding. A cross-sectional study was performed comparing haemophilia A carriers to normal women. Questionnaire assessment included a general bleeding questionnaire, condensed MCMDM-1VWD bleeding assessment tool and Pictorial Bleeding Assessment Chart (PBAC). Laboratory assessment included complete blood count, prothrombin time, activated partial thromboplastin time, fibrinogen activity, FVIII activity (

FVIII

C), von Willebrand factor antigen level, ristocetin cofactor, platelet function analyser-100(TM) and ABO blood type. Forty-four haemophilia A carriers and 43 controls were included. Demographic features were similar. Laboratory results demonstrated a statistically significant difference only in

FVIII

C (82·5 vs. 134%, P < 0·001). Carriers reported a higher number of bleeding events, and both condensed MCMDM-1 VWD bleeding scores (5 vs. 1, P < 0·001) and PBAC scores (423 vs. 182·5, P = 0·018) were significantly higher in carriers. Haemophilia A carriers exhibit increased bleeding symptoms when compared to normal women. Further studies are necessary to fully understand the bleeding phenotype in this population and optimize clinical management.

Haemorrhagic complications with adenotonsillectomy in children and young adults with bleeding disorders

Haemorrhagic complications remain a challenge with surgical procedures in patients with bleeding disorders. In children and young adults, the most commonly performed surgeries are tonsillectomies and/or adenoidectomies. Adequate haemostasis in these patients with bleeding disorders is centred on comprehensive perioperative haemostatic support and dexterous surgical technique. The aim of this study was to assess postoperative bleeding complications with tonsillectomy and/or adenoidectomy in children and young adults with known bleeding disorders. Retrospective review of all patients aged <25 years with known bleeding disorders who underwent tonsillectomy and/or adenoidectomy at Mayo Clinic, Rochester MN between July 1992 and July 2012. In contrast to reported literature, we observed a higher rate of bleeding complications (10/19, 53%) despite aggressive haemostatic support and appropriate surgical techniques. Delayed bleeding (>24 h postoperatively) was more common than early bleeding; and recurrent bleeding was associated with older age. Children and young adults with haemorrhagic diatheses undergoing adenotonsillectomy are at a higher risk of delayed bleeding and require close monitoring with haemostatic support for a prolonged duration in the postoperative period. A uniform approach is needed to manage these patients perioperatively by establishing standard practice guidelines and ultimately reduce postsurgical bleeding complications.

Females with FVIII and FIX deficiency have reduced joint range of motion

Little is known about rates of joint bleeding among females with FVIII/FIX deficiency or hemophilia carriers. In a cross-sectional study, we tested the hypothesis that females with FVIII or FIX deficiency enrolled in the Universal Data Collection (UDC) project had a reduced mean overall joint range of motion (ROM) compared with historic controls from the Normal Joint Study. Demographics, clinical characteristics, and joint ROM measurements on 303 females without a bleeding disorder and 148 females with FVIII and FIX deficiency, respectively, between the ages of 2-69 years and a body mass index (BMI) ≤ 35 were compared. Multivariate linear regression was performed with the overall joint ROM (sum of the right and left ROM measurements of five joints) as the dependent variable and FVIII or FIX activity as the independent variable adjusting for age, race, BMI, and number of joint bleeds reported over the last 6 months. As FVIII and FIX activity decreased, the mean overall joint ROM became reduced and in most cases was significantly lower than that of the controls regardless of age and clinical hemophilia severity. Further investigation of reduced joint ROM as evidence of subclinical joint bleeding in females with FVIII and FIX deficiency is warranted.