Impact of sex, age, race, ethnicity and aspirin use on bleeding symptoms in healthy adults

Identifying racial disparities in hereditary hemorrhagic telangiectasia

BACKGROUND

Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant disorder characterized by recurrent epistaxis (nose bleeds), mucosal telangiectasias (spider veins), and arteriovenous malformations. Although HHT affects all racial groups, few studies have explored racial disparities among patients with HHT.

METHODS

We performed a retrospective chart review of HHT patients who were seen at a single academic center between July 1, 2014 and January 1, 2022. The primary outcomes of this study were the Epistaxis Severity Score (ESS) and the presence of pulmonary, cerebral, gastrointestinal, spinal, and hepatic arteriovenous malformations (AVMs). We analyzed racial differences using t-tests and analysis of variance (ANOVA) for continuous variables, and chi-squared tests for categorical variables. We then performed multivariable linear and logistic regressions on outcomes.

RESULTS

Our review identified 35 Asian, 6 Black or African American, 72 Hispanic or Latino, and 244 White or Caucasian patients who met the inclusion criteria. Through an analysis of variance model, race/ethnicity was not significantly associated with ESS. Two univariable logistic regression models between race and both pulmonary and brain AVMs showed that race was associated with the incidence of pulmonary AVMs (p<0.01), with Asian patients at a 2.3-fold increased risk of pulmonary AVMs compared with White patients (p=0.03). Race was also associated with the incidence of cerebral AVMs (p<0.01) with Hispanic or Latino patients at a 4.8-fold increased risk compared with White patients (p<0.01).

CONCLUSION

Patients who identified as Asian may have higher rates of pulmonary AVMs while patients identifying as Hispanic or Latino may have more cerebral AVMs. The correlations may be important for identifying risk factors in certain patient populations.

The Influence of Hypothyroid Metabolic Status on Blood Coagulation and the Acquired von Willebrand Syndrome

The intent of this prospective study aimed to identify the influence of hypothyroid metabolic status on the coagulation and fibrinolytic system and association with the acquired von Willebrand syndrome (VWS-ac). We compared 54 patients without substitution therapy after radical thyroidectomy with 58 control subjects without pathological thyroid-stimulating-hormone (TSH)-values. Patients with TSH > 17.5 mU/L over a period of >4 weeks were included. The control-collective was selected based on age and sex to match the patient-collective. The data were collected using laboratory coagulation tests and patient questionnaires; a bleeding score was determined. There were significant differences in the measurement of activated-partial-thromboplastin-time (aPTT/p = 0.009), coagulation-factor VIII (p < 0.001) and von-Willebrand-activity (VWF-ac/p = 0.004) between the patient and control groups. The patient cohort showed an increased aPTT and decreased factor VIII and VWF-ac. 29.7% of the patient-collective compared to 17.2% of the control subjects met the definition of VWS-Ac (p = 0.12). The bleeding score showed significantly more bleeding symptoms in patients with a laboratory constellation of VWS-ac (no family history; p = 0.04). Our results suggest hypocoagulability in hypothyroid patients. Hypothyroidism appears to have a higher incidence of VWS-ac. The increased risk of bleeding complications in hypothyroid patients may be of relevant importance for the outcome, especially in the context of invasive interventions.

Variability in International Society on Thrombosis and Haemostasis-Scientific and Standardization Committee endorsed Bleeding Assessment Tool (ISTH-BAT) score with normal aging in healthy females: contributory factors and clinical significance

BACKGROUND

Bleeding assessment tools are key screening tests used in the evaluation of patients with suspected inherited bleeding disorders. The International Society on Thrombosis and Haemostasis-Scientific and Standardization Committee endorsed Bleeding Assessment Tool (ISTH-BAT) has differing reference ranges for adult males (0-3), adult females (0-5), and children (0-2), reflecting differing bleeding symptoms and exposure to hemostatic challenges in these healthy population subgroups. Age is known to markedly impact bleeding score in individuals with von Willebrand disease. However, the influence of age on bleeding score in healthy adult controls is poorly understood.

OBJECTIVES

We aimed to assess variability in ISTH-BAT score with age among healthy control females.

METHODS

We used the legacy "Merging Project" dataset of normal healthy controls upon which current ISTH-BAT normal ranges are based. We included women, totaling 646 individuals. The normal range (middle 95th percentile) of total ISTH-BAT and grouped subdomain scores between age quartiles was assessed.

RESULTS

The normal range of ISTH-BAT scores increased with age, ranging from 0 to 4 in the youngest quartile (age range, 18-30) to 0 to 6 in the oldest (age range, 52-88). This increased variability with aging was related both to high menorrhagia domain scores in older women and an increase in postprocedural bleeding with accumulated exposure to hemostatic challenges.

CONCLUSIONS

Cumulatively, our data highlight that normal aging leads to increased variability in bleeding scores in healthy adult females. Further refinement of the ISTH-BAT with age-adjusted reference ranges may improve the sensitivity and specificity of the tool among females.

Assessing Bleeding Symptoms in Pediatric Patients With Generalized Joint Hypermobility

OBJECTIVE

To assess bleeding symptoms in patients with generalized/benign joint hypermobility (GJH), compare bleeding scores to healthy historical pediatric controls, and determine whether a correlation exists between Beighton scores and bleeding scores.

METHODS

Patients with GJH ages 6-21 years seen by the rheumatology department at Nationwide Children's Hospital in Columbus, Ohio were eligible. Participants/guardians completed the International Society on Thrombosis and Haemostasis Bleeding Assessment Tool, a validated questionnaire defining the presence, severity, and frequency of bleeding symptoms. Scores of ≥3 have been associated with an underlying bleeding disorder in pediatric patients.

RESULTS

Eighty-one patients agreed to participate. The median age was 13 years (interquartile range 10-16 years), and the mean Beighton score was 6.3 (range 4-9). Commonly observed bleeding symptoms were oral bleeding (74%), easy bruising (59%), and bleeding with minor wounds (42%). Mean and median bleeding scores were 5.2 and 4, respectively, and were significantly higher than reported bleeding scores in pediatric controls, defined as those without bleeding symptoms or a previously diagnosed bleeding disorder (P < 0.001). Although 75% of patients (95% confidence interval 64-84) had an abnormal bleeding score, only 12.3% were previously assessed by hematology for bleeding symptoms. Among patients with GJH, higher Beighton scores were not associated with higher bleeding scores (Spearman's correlation -0.08).

CONCLUSION

In a cohort of pediatric patients with GJH, three-fourths of participants had abnormal bleeding scores, with the mean bleeding score significantly elevated compared to healthy controls. We propose that screening for bleeding symptoms be integrated into routine care for GJH patients, with referral to hematology for patients with bleeding concerns.

Interaction of von Willebrand factor with blood cells in flow models: a systematic review

The presence of blood flow influences the interaction between von Willebrand factor (VWF) and blood cells, affecting characteristics of forming blood clots. The interactions between coagulation and inflammation have mainly been studied in thrombosis models, but it remains unclear whether these interactions might also play a role in reduced bleeding in patients with bleeding disorders. In this systematic review, we provide an overview of the literature investigating the interactions between VWF and blood cells in flow models. For article selection, a systematic search was performed in Embase, Medline-Ovid, Cochrane Library, Web of Science databases, and Google Scholar. After selection, 24 articles were included. These articles describe direct or platelet-dependent interactions between VWF and neutrophils, monocytes, erythrocytes, or lymphocytes under different flow conditions. Almost all the described interactions required the presence of activated platelets. Only erythrocytes, monocytes, and natural killer cells were capable of directly binding the VWF multimers. Overall, interactions between VWF and blood cells mainly occurred in the presence of platelets. Because of the large variation in study design and used flow rates, further research is necessary to compare the results between studies and draw firm conclusions on when and under what conditions these interactions can occur. After our findings, many questions remained unanswered. This review might provide a starting point for future research. Extended knowledge on the influence of blood flow on VWF and blood cell interactions can contribute to improved understanding of the variation in bleeding in patients with bleeding disorders.

Screening and diagnosis of inherited platelet disorders

Inherited platelet disorders are important conditions that often manifest with bleeding. These disorders have heterogeneous underlying pathologies. Some are syndromic disorders with non-blood phenotypic features, and others are associated with an increased predisposition to developing myelodysplasia and leukemia. Platelet disorders can present with thrombocytopenia, defects in platelet function, or both. As the underlying pathogenesis of inherited thrombocytopenias and platelet function disorders are quite diverse, their evaluation requires a thorough clinical assessment and specialized diagnostic tests, that often challenge diagnostic laboratories. At present, many of the commonly encountered, non-syndromic platelet disorders do not have a defined molecular cause. Nonetheless, significant progress has been made over the past few decades to improve the diagnostic evaluation of inherited platelet disorders, from the assessment of the bleeding history to improved standardization of light transmission aggregometry, which remains a "gold standard" test of platelet function. Some platelet disorder test findings are highly predictive of a bleeding disorder and some show association to symptoms of prolonged bleeding, surgical bleeding, and wound healing problems. Multiple assays can be required to diagnose common and rare platelet disorders, each requiring control of preanalytical, analytical, and post-analytical variables. The laboratory investigations of platelet disorders include evaluations of platelet counts, size, and morphology by light microscopy; assessments for aggregation defects; tests for dense granule deficiency; analyses of granule constituents and their release; platelet protein analysis by immunofluorescent staining or flow cytometry; tests of platelet procoagulant function; evaluations of platelet ultrastructure; high-throughput sequencing and other molecular diagnostic tests. The focus of this article is to review current methods for the diagnostic assessment of platelet function, with a focus on contemporary, best diagnostic laboratory practices, and relationships between clinical and laboratory findings.

A Component or Multiple Components of Bleeding Gums May Ameliorate Both Glaucoma and Alzheimer’s Disease

Background: Although clinical studies have shown an increased prevalence of primary open-angle glaucoma (POAG) in patients with Alzheimer’s disease (AD), a population-based epidemiologic study from Denmark found no increased risk of Alzheimer’s disease in patients with glaucoma, and other studies have failed to demonstrate a link. However, a possible relationship between POAG and AD might manifest in their association with oral pathology. Dental caries, periodontal disease, stomatitis, and the related inflammatory burden increase AD risk, while oral pathology and the oral microbiome correlate with POAG vulnerability. To further examine the relationship, we analyzed POAG, AD, and oral disease in the UK Biobank (UKBB) cohort.

Methods: Our analysis included all subjects with POAG and AD. POAG diagnosis was ascertained using the 10th Revision of the International Classification of Diseases (ICD-10), H40.11. AD diagnosis was ascertained using the 10th Revision of the International Classification of Diseases (ICD-10), G30. Oral cavity, ulceration, stomatitis, periodontitis, teeth, and dental problems were in UKBB data field 6149.

Results: A “yes” answer to a question about bleeding gums is associated with a greater proportional POAG reduction (24.2%) than a “yes” answer to having none of the six listed problems (6.3%). Similarly, bleeding gums were associated with a greater proportional AD reduction (46.2% versus 16.9%). Logistic regression controlling for age and sex showed that bleeding gums (no/yes) were negatively associated with AD (odds ratio (OR) = 0.713, 95% confidence interval (CI) = 0.521-0.976, p = 0.035). Age-weighted least-squares linear regression showed that the lower corneal-compensated intraocular pressure (IOP) in the left eye was associated with bleeding gums (unstandardized regression coefficient = -0.174, p < 0.001), controlling for type 2 diabetes and past smoking.

Conclusion: It is difficult to predict what component or components of periodontal inflammation might be ameliorating POAG and AD. Prostaglandin is a possibility. Identification of the component or components could lead to new treatments for POAG and AD. Further studies are warranted.

Prevalence of bleeding symptoms among young adults in Saudi Arabia, a national survey

Prevalence of bleeding disorders vary due to several factors including geographical location. Mild bleeding disorders can lead to iron deficiency, morbidity, and in severe cases mortality. Quantification of haemorrhagic symptoms is a key component in management of bleeding disorders and a challenging task for clinicians.An abridged version of MCMDM-1vWD questionnaire with validated Arabic translation was used to quantify bleeding disorders in adult students (n = 1138) in 4 different regions of Kingdom of Saudi Arabia. Statistical analysis was performed to indicate gender disparity and prevalence.74.5% of respondents answered at least 1 question with affirmation, with 32.3% affected in Riyadh showing the highest prevalence and 14.03% affected in Dammam showing the least prevalence (P-value < .001). Gender-wise, higher prevalence of bleeding disorders in females 54.9% than in males 45.1% was observed (P-value .01). Epistaxis prevalence was significantly higher in males 30.7% vs 23.2% in females (P-value .0004), while cutaneous symptoms were reported significantly more by female participants 29.7% vs 12.3% in males (P-value < .001). Menorrhagia was reported by 28% of females, with heavy bleeding experienced by 57.6% female participants for <7 days while in 42.4% of females for >7 days.The current study signifies the ethnic distribution and gender disparity of mild bleeding disorders, and highlights the need for national surveillance system in order to improve management of patients with bleeding disorders.

Prevalence of bleeding symptoms among young adults in Saudi Arabia, a national survey

ABSTRACT

Prevalence of bleeding disorders vary due to several factors including geographical location. Mild bleeding disorders can lead to iron deficiency, morbidity, and in severe cases mortality. Quantification of haemorrhagic symptoms is a key component in management of bleeding disorders and a challenging task for clinicians.An abridged version of MCMDM-1vWD questionnaire with validated Arabic translation was used to quantify bleeding disorders in adult students (n = 1138) in 4 different regions of Kingdom of Saudi Arabia. Statistical analysis was performed to indicate gender disparity and prevalence.74.5% of respondents answered at least 1 question with affirmation, with 32.3% affected in Riyadh showing the highest prevalence and 14.03% affected in Dammam showing the least prevalence (P-value < .001). Gender-wise, higher prevalence of bleeding disorders in females 54.9% than in males 45.1% was observed (P-value .01). Epistaxis prevalence was significantly higher in males 30.7% vs 23.2% in females (P-value .0004), while cutaneous symptoms were reported significantly more by female participants 29.7% vs 12.3% in males (P-value < .001). Menorrhagia was reported by 28% of females, with heavy bleeding experienced by 57.6% female participants for <7 days while in 42.4% of females for >7 days.The current study signifies the ethnic distribution and gender disparity of mild bleeding disorders, and highlights the need for national surveillance system in order to improve management of patients with bleeding disorders.

Safety of apixaban in Indian patients undergoing elective total knee replacement or total hip replacement surgery: A multi-center, phase-IV study

Background:

Venous thromboembolism is a significant source of morbidity and mortality following total hip replacement and total knee replacement. Apixaban has been proven to be efficacious without increased risk of bleeding in phase-III trials in patients undergoing total knee replacement and total hip replacement. Due to paucity of data on safety of apixaban in Indian patients, this phase-IV study was conducted to evaluate safety of apixaban in patients undergoing total knee replacement and total hip replacement.

Methods:

In this non-comparative phase-IV clinical trial, patients undergoing elective total knee replacement or total hip replacement surgery, or a revision of at least one component of total knee replacement or total hip replacement, were enrolled. The eligible patients were given the approved dosage of apixaban 12 to 24 h after completing the skin wound closure. The primary safety outcome was the composite of the International Society on Thrombosis and Haemostasis–defined major bleeding and clinically relevant non-major bleeding events at the end of the treatment. The secondary efficacy endpoint was the composite of venous thromboembolism/all-cause death at the end of the treatment.

Results:

A total of 498 patients received apixaban prophylaxis therapy. Six (1.2%) bleeding adverse events were observed during the treatment period. Only one bleeding event was adjudicated as an International Society on Thrombosis and Haemostasis–defined clinically relevant non-major bleeding event (moderate severity). There were no fatal bleeding events and no deaths following the treatment. One venous thromboembolism event, that is, symptomatic distal left leg DVT, was reported in a total knee replacement patient and was adjudicated during the treatment period.

Conclusion:

Apixaban demonstrated a favorable safety profile for venous thromboembolism prevention in Indian patients undergoing total knee replacement or total hip replacement.

Approach to the Patient with Bleeding

Approach to the patient with bleeding begins with a thorough bleeding, medical, and family history to determine the nature of bleeding and severity of bleeding symptoms. Use of a Bleeding Assessment Tool allows the clinician to obtain a comprehensive bleeding history and ultimately determine the individual bleeding score that reflects bleeding severity and is classifiable as either normal or abnormal. In the absence of significant findings within patient history or presenting symptoms clearly pointing to a specific bleeding pathology, an approach to laboratory investigation is presented that proceeds through first-line, second-line, and third-line testing.

Outcome of Surgical Interventions and Deliveries in Patients with Bleeding of Unknown Cause: An Observational Study

BACKGROUND

 The most optimal management for patients with bleeding of unknown cause (BUC) is unknown, as limited data are available.

OBJECTIVE

 Evaluate management and outcome of surgical procedures and deliveries in patients with BUC.

MATERIALS AND METHODS

 All patients ≥12 years of age, referred to a tertiary center for a bleeding tendency, were included. Bleeding phenotype was assessed and hemostatic laboratory work-up was performed. Patients were diagnosed with BUC or an established bleeding disorder (BD). Data on bleeding and treatment during surgical procedures and delivery following diagnosis were collected.

RESULTS

 Of 380 included patients, 228 (60%) were diagnosed with BUC and 152 (40%) with an established BD. In 14/72 (19%) surgical procedures major bleeding occurred and 14/41 (34%) deliveries were complicated by major postpartum hemorrhage (PPH). More specifically, 29/53 (55%) of the BUC patients who underwent surgery received prophylactic treatment to support hemostasis. Despite these precautions, 4/29 (14%) experienced major bleeding. Of BUC patients not treated prophylactically, bleeding occurred in 6/24 (25%). Of pregnant women with BUC, 2/26 (8%) received prophylactic treatment during delivery, one women with and 11 (46%) women without treatment developed major PPH.

CONCLUSION

 Bleeding complications are frequent in BUC patients, irrespective of pre- or perioperative hemostatic treatment. We recommend a low-threshold approach toward administration of hemostatic treatment in BUC patients, especially during delivery.

Low-Dose Aspirin Use Among African American Older Adults

OBJECTIVES

Existing epidemiologic information shows disparities in low-dose aspirin use by race. This study investigates the frequency, pattern, and correlates of both self- and clinician-prescribed low-dose aspirin use among underserved African Americans aged 55 years and older.

METHODS

This cross-sectional study conducted a comprehensive evaluation of all over-the-counter and prescribed medications used among 683 African American older adults in South Central Los Angeles, California. Correlation between use of low-dose aspirin and sociodemographic variables, health care continuity, health behaviors, and several major chronic medical conditions were examined. In addition, the use of low-dose aspirin as self prescribed versus clinician prescribed was examined. Multivariate logistic regression was performed to examine correlates of low-dose aspirin use.

RESULTS

Overall, 37% of participants were taking low-dose aspirin. Sixty percent of low-dose aspirin users were taking low-dose aspirin as self prescribed and 40% were taking it as prescribed by a clinician. Major aspirin-drug interactions were detected in 75% of participants who used low-dose aspirin, but no significant differences in aspirin-drug interactions were found between those who used aspirin as self prescribed and those who used it as clinician prescribed. No negative association between being diagnosed with gastrointestinal conditions and aspirin used was detected. Being diagnosed with diabetes mellitus or a heart condition was associated with higher use of aspirin. However, only 50% with high risk of cardiovascular took prescribed (38%) or self-prescribed (62%) low-dose aspirin. One third of participants aged 70 years and older with low risk of cardiovascular were using aspirin.

CONCLUSIONS

Among underserved African-American middle-aged and older adults, many who could potentially benefit from aspirin are not taking it; and many taking aspirin have no indication to do so and risk unnecessary side effects. Compared with non-Hispanic Whites, African Americans are more likely to be diagnosed with diabetes, hypertension, and heart conditions at earlier stages of life; as a result, the role of preventive intervention, including safe and appropriate use of low-dose aspirin among this segment of our population, is more salient. Interventional studies are needed to promote safe and effective use of low-dose aspirin among underserved African-American adults.

Bleeding of unknown cause and unclassified bleeding disorders; diagnosis, pathophysiology and management

Bleeding of unknown cause (BUC), also known as unclassified bleeding disorders (UBD), has been defined as a clear bleeding tendency in the presence of normal haemostatic tests. There are challenges in the diagnosis and management of these patients. BUC/UBD encompasses a heterogenous group of disorders which may include undiagnosed rare monogenic diseases, polygenic reasons for bleeding; and patients without a clear bleeding disorder but with a previous bleeding event. Nevertheless, these patients may have heavy menstrual bleeding or be at risk of bleeding when undergoing surgical procedures, or childbirth; optimizing haemostasis and establishing a mode of inheritance is important to minimize morbidity. The bleeding score has been used to clinically assess and describe these patients, but its value remains uncertain. In addition, accurate distinction between normal and pathological bleeding remains difficult. Several studies have investigated cohorts of these patients using research haemostasis tests, including thrombin generation and fibrinolytic assays, yet no clear characteristics have consistently emerged. Thus far, detailed genetic analysis of these patients has not been fruitful in unravelling the cause of bleeding. There is a need for standardization of diagnosis and management guidelines for these patients. This review gives an overview of this field with some suggestions for future research.

The discriminatory power of bleeding assessment tools in adult patients with a mild to moderate bleeding tendency

BACKGROUND

Bleeding assessment tools (BATs) have been developed to quantify bleeding severity. Their ability to predict for the diagnosis of a bleeding disorder has not been thoroughly investigated.

OBJECTIVES

To evaluate the ability of the Vicenza BAT and the ISTH BAT to distinguish patients with an established bleeding disorder from those with bleeding of unknown cause (BUC).

PATIENTS/METHODS

Three-hundred fifty-nine patients (228 with BUC, 64%) from the Vienna Bleeding Biobank were assessed in this study.

RESULTS

The bleeding scores were similar in patients with an established diagnosis of a bleeding disorder compared to patients with BUC. Both BATs had a low sensitivity and specificity for the diagnosis of a bleeding disorder with areas under the receiver operating characteristic (ROC) curves of 0.53 (95% confidence interval 0.47-0.60) for the Vicenza BAT and 0.52 (0.46-0.59) for the ISTH BAT. In terms of specific diagnoses, both scores were most accurate in diagnosing von Willebrand disease (VWD, areas under the ROC curve; Vicenza BAT 0.67 (0.45-0.90); ISTH BAT 0.70 (0.50-0.90)). A separate evaluation of different bleeding symptoms in patients who had undergone surgery and tooth extraction revealed that postpartum bleeding and bleeding from small wounds was predictive for diagnosing a MBD in multivariable analysis.

CONCLUSIONS

The Vicenza- and the ISTH BAT have a low ability to distinguish patients with an established bleeding disorder from those with BUC.

Predicting ischaemic events using platelet reactivity in patients receiving clopidogrel: Indirect meta-comparison among VerifyNow, light transmission aggregometry and thromboelastography

The present study compared performances of the three major methods used for assessing platelet reactivity (PR)-VerifyNow, light transmission aggregometry (LTA) and thromboelastography (TEG)-to predict ischaemic events in patients receiving clopidogrel. PubMed, EMBASE and the Cochrane Library were searched from their inception to April 2019 for prospective studies that examined PR using VerifyNow, LTA or TEG and the incidence of ischaemic events. The investigated diagnostic indices include sensitivity, specificity, positive (PLR) and negative likelihood ratio (NLR), diagnostic odds ratio and area under the receiver operating characteristic curves (AUC) of VerifyNow, LTA and TEG, respectively. A total of 26 prospective studies involving 22 185 patients were included in the analysis. The pooled AUC was 0.71 (95% CI: 0.67-0.75) for VerifyNow, 0.60 (95% CI: 0.55-0.64) for LTA and 0.81 (95% CI: 0.77-0.84) for TEG. Results of indirect comparisons indicated the AUC of VerifyNow was higher than that of LTA (1.18, 95% CI: 1.08-1.30) and lower than that of TEG (0.88, 95% CI: 0.82-0.94). TEG outperformed the other two methods for assessing PR in all predictive measures, including sensitivity, specificity, PLR and NLR. Despite a lack of studies that directly compared the three methods, our findings suggest that TEG should be recommended.

Prediction of perioperative transfusions using an artificial neural network

BACKGROUND

Accurate prediction of operative transfusions is essential for resource allocation and identifying patients at risk of postoperative adverse events. This research examines the efficacy of using artificial neural networks (ANNs) to predict transfusions for all inpatient operations.

METHODS

Over 1.6 million surgical cases over a two year period from the NSQIP-PUF database are used. Data from 2014 (750937 records) are used for model development and data from 2015 (885502 records) are used for model validation. ANN and regression models are developed to predict perioperative transfusions for surgical patients.

RESULTS

Various ANN models and logistic regression, using four variable sets, are compared. The best performing ANN models with respect to both sensitivity and area under the receiver operator characteristic curve outperformed all of the regression models (p < .001) and achieved a performance of 70-80% specificity with a corresponding 75-62% sensitivity.

CONCLUSION

ANNs can predict >75% of the patients who will require transfusion and 70% of those who will not. Increasing specificity to 80% still enables a sensitivity of almost 67%. The unique contribution of this research is the utilization of a single ANN model to predict transfusions across a broad range of surgical procedures.

Diagnostic work up of patients with increased bleeding tendency

Introduction

The diagnostic trajectory of patients with increased bleeding tendency can be very costly and time‐consuming. In addition, previous studies have shown that half of these patients remain without final diagnosis despite all efforts.

Aim

This study aimed to improve insight into the current diagnostic process of these patients.

Methods

A total of 117 adult patients, referred to an academic hospital because of being suspected to have an increased bleeding tendency, were included. Different parameters were compared between patients receiving final diagnosis, patients without final diagnosis but a high Tosetto bleeding assessment tool (BAT) score (classified as bleeding of unknown cause, or BUC) and a control group consisting of patients without final diagnosis and a low BAT score.

Results

The BAT score was significantly higher in patients in the BUC group as compared to patients reaching final diagnosis (8.1 vs 4.9). Interestingly, the two subcategories most prevalently increased were surgery and post‐partum haemorrhage‐associated bleeding (surgery: 2.1 vs 1.1; post‐partum haemorrhage: 0.7 vs 0.0). Laboratory screening results were more often abnormal in patients reaching final diagnosis compared to patients remaining without diagnosis and a high BAT score (n = 32 (78%) vs n = 14 (46%), 95% CI 1.5‐12), especially concerning the PFA (=27 (66%) vs n = 10 (33%), 95% CI 1.4‐10) and von Willebrand factor activity levels (n = 11 (27%) vs n = 1 (3%), 95% CI 1.3‐91).

Conclusion

Isolated high bleeding score on surgical or post‐partum bleeding correlates with a lower chance of receiving final diagnosis. Withholding extensive haemostatic testing should be considered. Better screening and confirmative haemostatic assays are still needed.

Fundamentals for a Systematic Approach to Mild and Moderate Inherited Bleeding Disorders: An EHA Consensus Report

Healthy subjects frequently report minor bleedings that are frequently ‘background noise’ of normality rather than a true disorder. Nevertheless, unexpected or unusual bleeding may be alarming. Thus, the distinction between normal and pathologic bleeding is critical. Understanding the underlying pathologic mechanism in patients with an excessive bleeding is essential for their counseling and treatment. Most of these patients with significant bleeding will result affected by non-severe inherited bleeding disorders (BD), collectively denominated mild or moderate BD for their relatively benign course. Unfortunately, practical recommendations for the management of these disorders are still lacking due to the current state of fragmented knowledge of pathophysiology and lack of a systematic diagnostic approach. To address this gap, an International Working Group (IWG) was established by the European Hematology Association (EHA) to develop consensus-based guidelines on these disorders. The IWG agreed that grouping these disorders by their clinical phenotype under the single category of mild-to-moderate bleeding disorders (MBD) reflects current clinical practice and will facilitate a systematic diagnostic approach. Based on standardized and harmonized definitions a conceptual unified framework is proposed to distinguish normal subjects from affected patients. The IWG proposes a provisional comprehensive patient-centered initial diagnostic approach that will result in classification of MBD into distinct clinical-pathological entities under the overarching principle of clinical utility for the individual patient. While we will present here a general overview of the global management of patients with MBD, this conceptual framework will be adopted and validated in the evidence-based, disease-specific guidelines under development by the IWG.

Mild bleeding disorders: what every clinician should know

Patients with mild bleeding disorders are under-recognized and frequently present to general physicians. The underlying reasons for bleeding are multifactorial. There is little evidence to guide diagnostic and management decision making in patients with mild bleeding disorders. This article outlines different types of mild bleeding disorders, with a particular focus on bleeding associated with low levels of von Willebrand factor and mild platelet defects. It gives practical, evidence-based advice on the investigation and management of patients with a suspected or known mild bleeding disorder, considering the scenarios of an acute bleed, stable outpatient, peri-surgical management and thrombosis. Patients with a mild bleeding disorder have variable bleeding because of the interplay of genetic and environmental factors. The clinical history remains of utmost importance in their general management. Liaison with a specialist centre, multidisciplinary assessment and a careful judgement of the balance of risk in each individual circumstance is required to safely manage these patients.

Diagnostic challenges of inherited mild bleeding disorders: a bait for poorly explored clinical and basic research

The best-known inherited mild bleeding disorders (MBDs), i.e. type 1 von Willebrand disease (VWD), platelet function disorders (PFDs), and mild to moderate clotting factor deficiencies, are characterized clinically by mucocutaneous bleeding, and, although they are highly prevalent, still pose difficult diagnostic problems. These include establishing the pathological nature of bleeding, and the uncertainties surrounding the clinical relevance of laboratory results. Furthermore, the high frequency of bleeding symptoms in the normal population and the subjective appraisal of symptoms by patients or parents makes elucidating the pathological nature of bleeding difficult. Standardized bleeding assessment tools and semiquantitative bleeding scores (BSs) help to discriminate normal from abnormal bleeding. However, as most MBDs have similar bleeding patterns, for example, bleeding sites, frequency, and severity, BSs are of little help for diagnosing specific diseases. Global tests of primary hemostasis (bleeding time; PFA-100/200) lack sensitivity and, like BSs, are not disease-specific. Problems with the diagnosis of type 1 VWD and PFD include assay standardization, uncertain definition of von Willebrand factor cut-off levels, and the lack of universal diagnostic criteria for PFD. Regarding clotting factor deficiencies, the bleeding thresholds of some coagulation factors, such as factor VII and FXI, are highly variable, and may lead to misinterpretation of the clinical relevance of mild to moderate deficiencies. Remarkably, a large proportion of MBDs remain undiagnosed even after comprehensive and repeated laboratory testing. These are tentatively considered to represent bleeding of undefined cause, with clinical features indistinguishable from those of classical MBD; the pathogenesis of this is probably multifactorial, and unveiling these mechanisms should constitute a fertile source of translational research.

Evaluation and management of heavy menstrual bleeding in adolescents: the role of the hematologist

Heavy menstrual bleeding (HMB) is frequently reported by adolescents. The role of the hematologist is threefold in evaluating such patients: (1) perform a clinical and laboratory evaluation for an underlying bleeding disorder on the basis of the degree of clinical suspicion, (2) identify and manage any concomitant iron deficiency, and (3) provide input to the referring provider regarding the management of HMB, particularly for patients with identified hemostatic defects. Several clues in the menstrual history should raise suspicion for an underlying bleeding disorder, such as menses lasting >7 days, menstrual flow which soaks >5 sanitary products per day or requires product change during the night, passage of large blood clots, or failure to respond to conventional therapies. A detailed personal and family history of other bleeding symptoms should also be obtained. Iron deficiency with and without anemia is commonly found in young women with HMB. Therefore, it is important to obtain measures of hemoglobin and ferritin levels when evaluating these patients. Iron supplementation is often a key component of management in the adolescent with heavy menses and is still needed in those who have received packed red cell transfusions as a result of severe anemia. Strategies for decreasing menstrual blood flow are similar for adults and adolescents with heavy menses, with combined hormonal contraceptives recommended as first-line therapy. However, there are adolescent-specific considerations for many of these agents, and they must be incorporated into shared decision-making when selecting the most appropriate treatment.

Evaluation and management of heavy menstrual bleeding in adolescents: the role of the hematologist

Heavy menstrual bleeding (HMB) is frequently reported by adolescents. The role of the hematologist is threefold in evaluating such patients: (1) perform a clinical and laboratory evaluation for an underlying bleeding disorder on the basis of the degree of clinical suspicion, (2) identify and manage any concomitant iron deficiency, and (3) provide input to the referring provider regarding the management of HMB, particularly for patients with identified hemostatic defects. Several clues in the menstrual history should raise suspicion for an underlying bleeding disorder, such as menses lasting &gt;7 days, menstrual flow which soaks &gt;5 sanitary products per day or requires product change during the night, passage of large blood clots, or failure to respond to conventional therapies. A detailed personal and family history of other bleeding symptoms should also be obtained. Iron deficiency with and without anemia is commonly found in young women with HMB. Therefore, it is important to obtain measures of hemoglobin and ferritin levels when evaluating these patients. Iron supplementation is often a key component of management in the adolescent with heavy menses and is still needed in those who have received packed red cell transfusions as a result of severe anemia. Strategies for decreasing menstrual blood flow are similar for adults and adolescents with heavy menses, with combined hormonal contraceptives recommended as first-line therapy. However, there are adolescent-specific considerations for many of these agents, and they must be incorporated into shared decision-making when selecting the most appropriate treatment.

Whole exome sequencing in the diagnostic workup of patients with a bleeding diathesis

INTRODUCTION

Bleeding assessment tools and laboratory phenotyping often remain inconclusive in patients with a haemorrhagic diathesis.

AIM

To describe the phenotype and genetic profile of patients with a bleeding tendency.

METHODS

Whole exome sequencing (WES) was incorporated in the routine diagnostic pathway of patients with thrombocytopenia (n = 17), platelet function disorders (n = 19) and an unexplained bleeding tendency (n = 51). The analysis of a panel of 126 OMIM (Online Mendelian Inheritance in Man) genes involved in thrombosis and haemostasis was conducted, and if negative, further exome-wide analysis was performed if informed consent given.

RESULTS

Eighteen variants were detected in 15 patients from a total of 87 patients (17%). Causative variants were observed in MYH9 (two cases), SLFN14, P2RY12 and GP9. In addition, one case was considered solved due to combined carriership of F7 and F13A1 variants and one with combined carriership of F2, F8 and VWF, all variants related to secondary haemostasis protein aberrations. Two variants of uncertain significance (VUS) were found in two primary haemostasis genes: GFI1B and VWF. Eight patients were carriers of autosomal recessive disorders. Exome-wide analysis was performed in 54 cases and identified three variants in candidate genes.

CONCLUSION

Based on our findings, we conclude that performing WES at the end of the diagnostic trajectory can be of additive value to explain the complete bleeding phenotype in patients without a definite diagnosis after conventional laboratory tests. Discovery of combinations of (novel) genes that predispose to bleeding will increase the diagnostic yield in patients with an unexplained bleeding diathesis.

Preoperative screening for bleeding disorders: A comprehensive laboratory assessment of clinical practice

BACKGROUND

Patients with mild bleeding disorders are at risk of perioperative bleeding, but screening for these disorders remains challenging.

OBJECTIVES

We aimed to assess the prevalence of hemostatic abnormalities in patients with and without reported bleeding symptoms on a preoperative questionnaire, consisting of guideline-proposed questions, and appraised the diagnostic value of several screening modalities for the identification of patients with hemostatic abnormalities.

METHODS

In this observational study, 240 patients with and 95 patients without bleeding symptoms on the preoperative questionnaire were included. Patients with known bleeding disorders, antithrombotic drugs, thrombocytopenia, and anemia were excluded. Preoperatively, all patients underwent elaborate hemostatic testing. Hemostatic abnormalities were defined as coagulation, vWF, or fibrinolysis factor levels below reference range and platelet function defects. Screening modalities included the ISTH Bleeding Assessment Tool (ISTH-BAT), PT, aPTT, TT, Euglobulin Lysis Time (ELT), and Platelet Function Analyser (PFA).

RESULTS

In 21 of 240 (8.8%) patients reporting bleeding symptoms, hemostatic abnormalities were found, including 7 reduced coagulation factor levels, 10 platelet function abnormalities, and 4 reduced vWF levels. In comparison, 10 of 95 (10.5%) patients not reporting bleeding symptoms had abnormalities. The ISTH-BAT could not identify patients with abnormalities, while PT, aPTT, TT, ELT, and PFA had high specificity but low sensitivity to detect abnormalities.

CONCLUSIONS

The prevalence of hemostatic abnormalities in both patients with and without reported bleeding symptoms was 9%-10%. This suggests that the guideline-based questionnaire cannot differentiate between patients with and without abnormalities, while the discriminative power of the screening modalities is also limited.

High proportion of patients with bleeding of unknown cause in persons with a mild-to-moderate bleeding tendency: Results from the Vienna Bleeding Biobank (VIBB)

INTRODUCTION

Data on clinical characteristics and the prevalence of underlying coagulopathies in patients with mild-to-moderate bleeding disorders (MBDs) are scarce.

AIM

We established the Vienna Bleeding Biobank (VIBB) to characterize and thoroughly investigate Austrian patients with MBDs.

RESULTS

Four hundred eighteen patients (female = 345, 82.5%) were included. A platelet function defect (PFD) was diagnosed in 26 (6.2%) and a possible PFD in 30 (7.2%) patients. Eight patients (1.9%) were diagnosed with von Willebrand disease (VWD) (type 1 n = 6; type 2 n = 2), and 29 patients had low VWF (30-50 IU/dL). Deficiencies in factor VIII, IX, XI or XIII were found in 11 (2.6%), 3 (0.7%), 3 (0.7%) and 1 patient(s), 2 patients had dysfibrinogenaemia, and further 2 had possible PFD and FXI deficiency. Probable causal mutations were detected in 8 of 11 patients with FVIII deficiency, 2 of 3 patients with FIX deficiency and 2 of 8 patients with VWD. Three hundred three patients (72.5%) had normal results in the coagulation assays and were categorized as patients with bleeding of unknown cause (BUC). The bleeding score did not differ between patients with and without established diagnosis. A diagnosis of a bleeding disorder was more frequently made in men than in women (49.3% vs 22.9%). Male sex (OR 3.55, 95% CI: 2.02-6.22; P < .001) and blood group 0 (OR 1.86, 95% CI: 1.17-2.94; P = .008) were independently associated with diagnosis of a bleeding disorder.

CONCLUSION

The high rate of patients with BUC despite in-depth haemostatic assessment underlines the incompleteness of available routine laboratory tests. Males with MBDs were more likely to be diagnosed with an established bleeding disorder than females.

Bleeding score in Type 1 von Willebrand disease patients using the ISTH-BAT questionnaire

BACKGROUND

Bleeding assessment tools have evolved in the last decade to standardize the assessment of the severity of bleeding symptom in a consistent way. In 2010, the International Society on Thrombosis and Hemostasis-Bleeding Assessment Tool (ISTH-BAT) was developed and validated.

AIMS

Our aim was to administer ISTH-BAT questionnaire to the Omani patients with type 1 VWD and obtain the bleeding score (BS). We also studied the severity of their bleeding symptoms and correlated it with the BS as well as with the laboratory parameters.

METHODS

Forty-eight type I VWD index cases and 52 normal subjects were interviewed and the ISTH-BAT questionnaire administered. The BS was calculated based on a history of bleeding symptoms from 12 different sites according to the standard ISTH-BAT questionnaire. Laboratory parameters were obtained from patient's medical records.

RESULTS

The mean age of this cohort was 27 years (range, 6-49) with 60% being females. The median time to administer this questionnaire was 10 minutes with an interquartile range (IQR) from 8 to 17 minutes. Overall, the median BS was 7 (IQR; 2,11) although individual scores ranged between 0 and 36. The BS was negatively correlated with VWF: Ag, VWF: RCo, and VWF: CB and the Spearman's correlation coefficient "rho" was, respectively, -0.15, -0.08, and -0.22.

CONCLUSION

The ISTH-BAT BS is designed to reflect the severity of bleeding. Our results demonstrate the inherent variability of this bleeding pattern. We also found that the ISTH-BAT BS significantly correlated with VWF: Ag and VWF: CB.

Laboratory evaluation of patients with undiagnosed bleeding disorders

The evaluation of patients with a bleeding tendency represents a challenge as the routinely available tests for evaluating bleeding disorders are limited, complicating the laboratory determination of the clinically observed bleeding tendency. As a result, some bleeding disorders remain undiagnosed. The aim of the study was to evaluate whether global coagulation tests would contribute to the laboratory analysis of patients with undiagnosed bleeding disorders. Patients were evaluated for coagulation and fibrinolysis activities by thrombin generation test and euglobulin lysis time. In addition, plasma activity of factor XIII, plasminogen, α-2 antiplasmin, plasminogen activator inhibitor-1, and thrombin-activatable fibrinolysis inhibitor was also obtained. Forty-five patients were included. Eight per cent presented a mild bleeding disorder and 20% a moderate bleeding disorder. The thrombin generation test results were similar between patients and controls. Euglobulin lysis time results, however, were lower in patients than in controls, both before (median 175 vs. 250 min, respectively; P = 0.003) and after (median 145 vs. 115 min, respectively; P ≤ 0.001) arm constriction, suggesting that they were experiencing hyperfibrinolysis. Interestingly, patients' median thrombin-activatable fibrinolysis inhibitor activity was higher than in controls (21.2 vs. 19.46 μg/ml; P = 0.016). However, plasminogen, α-2 antiplasmin, plasminogen activator inhibitor-1, and factor XIII activities did not differ between the groups. Global coagulation and fibrinolysis tests proved to be limited in detecting the hemostatic disorders in some patients with a relevant bleeding tendency and may not be adequate to address their bleeding risk. Bleeding scores are currently the available medical approach for the evaluation of these patients.

Screening of female family members of von Willebrand disease patients: utility of a modified screening tool in a high-risk population

INTRODUCTION

Family members of Von Willebrand disease (VWD) patients may have low levels of VWF without major bleeding episodes and often remain undiagnosed.

AIM

The purpose of this study was to assess the utility of a modified Screening Tool in identifying previously untested reproductive age female family members of VWD patients for haemostatic evaluation.

METHODS

Ninety-four reproductive age women including 41 previously untested family members of VWD patients, 26 previously diagnosed VWD patients and 27 healthy controls were administered a modified Screening Tool and had blood drawn for CBC, ferritin, and VWF testing. Participants completed a pictorial blood assessment chart (PBAC) with menses.

RESULTS

The modified Screening Tool was positive in 32% family members, 77% VWD patients, and 19% controls (P < 0.001). Combined with low ferritin, the modified Screening Tool was positive in 66% family members, 92% VWD patients, and 44% controls (P = 0.001). In family members, incorporating low ferritin with the modified Screening Tool resulted in a sensitivity of 86% (95% CI, 42-100) and negative predictive value of 93% (95% CI, 66-100). In the control group, NPV was between 92% and 95% for the modified Screening Tool and also for the modified Screening Tool combined with low ferritin or a positive PBAC.

CONCLUSION

These data in a racially diverse population suggest the usefulness of a simple, easy to administer modified Screening Tool. In conjunction with ferritin it could be used in a primary care setting to stratify reproductive age women with a family history of VWD for haemostatic evaluation.

Novel approaches for diagnosing inherited platelet disorders

Inherited platelet disorders diagnosis is based on the clinical history and bleeding assessment tools. The laboratory functional assays as well as the molecular test to identify the pathogenic genetic variant are essential to confirm the accurate diagnosis of these disorders. Nowadays, the main challenges to developing a new diagnostic system are involved in reducing the samples' volume, and faster and more helpful analysis. Moreover, there are no widely available and standardised global tests. High throughput genetic testing such as next-generation sequencing has revolutionised DNA sequencing technologies as it allows the simultaneous and faster investigation of multiple genes at a manageable cost. This technology has improved the molecular characterisation of inherited platelet disorders and has been implemented in the research studies and the clinical routine practice.

Bleeding Diatheses: Approach to the Patient Who Bleeds or Has Abnormal Coagulation

Many complex elements contribute to normal hemostasis, and an imbalance of these elements may lead to abnormal bleeding. In addition to evaluating medication effects, the hematologist must evaluate for congenital or acquired deficiencies in coagulation factors and platelet disorders. This evaluation should include a thorough bleeding history with careful attention to prior hemostatic challenges and common laboratory testing, including coagulation studies and/or functional platelet assays. An accurate diagnosis of a bleeding diathesis and selection of appropriate treatment are greatly aided by a basic understanding of the mechanisms of disease and the tests used to diagnose them.

Bleeding spectrum in children with moderate or severe von Willebrand disease: Relevance of pediatric-specific bleeding

The bleeding phenotype of children with von Willebrand disease (VWD) needs to be characterized in detail to facilitate diagnosis during childhood and aid in the planning and assessment of treatment strategies. The objective was to evaluate the occurrence, type, and severity of bleeding in a large cohort of children with moderate and severe VWD. We included 113 children (aged 0-16 years) with Type 1 (n = 60), 2 (n = 44), and 3 (n = 9) VWD with von Willebrand factor (VWF) antigen and/or VWF ristocetin cofactor levels ≤ 30 U/dL from a nation-wide cross-sectional study ("Willebrand in the Netherlands" study). Bleeding severity and frequency were determined using the International Society on Thrombosis and Hemostasis-Bleeding Assessment Tool (ISTH-BAT) with supplementary pediatric-specific bleeding symptoms (umbilical stump bleeding, cephalohematoma, cheek hematoma, conjunctival bleeding, postcircumcision and postvenipuncture bleeding). We found that all 26 postmenarche girls experienced menorrhagia. Other common bleedings were cutaneous (81%), oropharyngeal (64%), prolonged bleeding from minor wounds (58%), and epistaxis (56%). Pediatric-specific bleeding symptoms were present in 44% of patients. ISTH-BAT bleeding score was higher in index cases than in affected family members (median, 12.0 vs. 6.5, P < 0.001), higher in Type 3 VWD than in Type 2 or 1 (17.0 vs. 10.5 or 6.5, P < 0.001) and higher in children with severe (<10 U/dL) than moderate VWD (10-30 U/dL) (11.0 vs. 7.0, P < 0.001). Frequency of any bleeding, epistaxis, and oral cavity was higher in types 2 and 3 than in Type 1 VWD and was associated with VWF levels. We conclude that pediatric-specific bleeding symptoms occurred in a large proportion of children with moderate or severe VWD and should be included when evaluating children for VWD.

Clotting factor level is not a good predictor of bleeding in carriers of haemophilia A and B

Carriers of haemophilia are known to have a wide range of clotting factor levels and bleeding symptoms. This study aimed at investigating whether carriers of severe and moderate haemophilia had an increased bleeding tendency, compared with a control group, using a condensed version of a bleeding assessment tool developed by the Molecular and Clinical Markers for the Diagnosis and Management of Type 1 VWD study group (MCMDM-1VWD). One hundred and twenty-six genetically verified carriers of severe and moderate haemophilia and 90 controls were interviewed regarding bleeding symptoms. A bleeding score of at least 4 was considered positive, indicating a significant bleeding tendency. Clotting factor levels were tested in the carriers.Nineteen of the women were carriers of haemophilia B, with a mean factor (F)IX:C level of 0.54 (± 0.27) kIU/l, and 107 were carriers of haemophilia A, with a mean FVIII:C level of 0.74 (± 0.32) kIU/l. The median bleeding score was 2 (-3-12) among carriers and -1 (-3-8) among controls (P < 0.001). The bleeding score was weakly correlated to clotting factor levels in carriers of haemophilia A (rs = -0.36, P < 0.001). We conclude that the bleeding tendency in our cohort of carriers differed significantly from that in the controls and that clotting factor levels might not be sufficient to predict the bleeding tendency.

Predictors of von Willebrand disease diagnosis in individuals with borderline von Willebrand factor plasma levels

BACKGROUND

In individuals with borderline von Willebrand factor (VWF) plasma levels, second-level tests are required to confirm or exclude von Willebrand disease (VWD). These tests are time-consuming and expensive.

OBJECTIVE

To assess which parameters can predict VWD diagnosis in individuals with borderline VWF levels (30-60 IU dL(-1) ).

METHODS

Nine hundred and fifty individuals with bleeding episodes or abnormal coagulation test results were investigated with first-level tests (blood count, prothrombin time, activated partial thromboplastin time, blood clotting factor VIII, VWF ristocetin cofactor activity [VWF:RCo], and VWF antigen), and 93 (62 females and 31 males; median age, 28 years; interquartile range 15-44) had borderline VWF:RCo levels. All underwent second-level investigations to confirm or exclude VWD. A multivariable logistic regression model was fitted with sex, age, bleeding score, family history, VWF:RCo and ABO blood group as predictors, and used to predict VWD diagnosis.

RESULTS

Forty-five of the 93 individuals (48%) had VWD (84% type 1). A negative linear relationship between VWF:RCo levels and risk of VWD diagnosis was present, and was particularly evident with blood group non-O [adjusted odds ratio 7.00 (95% confidence interval [CI] 1.48-33.11) for every 5 IU dL(-1) decrease in VWF:RCo]. The other variable clearly associated with VWD diagnosis was female sex (adjusted odds ratio 5.76 [95% CI 1.47-22.53]). The area under the receiver operating characteristic curve of the full logistic model was 0.89 (95% CI 0.82-0.95).

CONCLUSIONS

In individuals with borderline VWF, the two strongest predictors of VWD diagnosis are low VWF:RCo levels (particularly in those with blood group non-O) and female sex. This predictive model has a promising discriminative ability to identify patients with borderline VWF levels who are likely to have VWD.

Rare bleeding disorders - bleeding assessment tools, laboratory aspects and phenotype and therapy of FXI deficiency

Rare bleeding disorders (RBDs) are inherited deficiencies of coagulation factors such as fibrinogen, factor (F) II, FV, FVII, combined FV+FVIII, FX, FXI and FXIII. These disorders usually have a low prevalence in the general population and constitute approximately 3-5% of all coagulation disorders. However, in some countries they may have the same prevalence as haemophilia B due to the practice of consanguineous marriage. The clinical picture of RBDs is highly variable and can vary markedly from mild to severe, making both diagnosis and optimal treatment quite challenging. This review focuses on: (i) the efforts to establish a bleeding assessment tool adequate to RBDs, (ii) the optimal management of patients affected with FXI deficiency and (iii) the correlation between clinical severity and laboratory diagnosis when determining the minimum coagulant activity required to prevent bleeding in each RBD.

Normal range of bleeding scores for the ISTH-BAT: adult and pediatric data from the merging project

Bleeding Assessment Tools (BATs) have been developed to aid in the standardized evaluation of bleeding symptoms. The Vicenza Bleeding Questionnaire (BQ), published in 2005, established a common framework and scoring key that has undergone subsequent modification over the years, culminating in the publication of the ISTH-BAT in 2010. Understanding the normal range of bleeding scores is critical when assessing the utility of a BAT. Within the context of The Merging Project, a bioinformatics system was created to facilitate the merging of legacy data derived from four different (but all Vicenza-based) BATs; the MCMDM1-VWD BQ, the Condensed MCMDM-1VWD BQ, the Pediatric Bleeding Questionnaire and the ISTH-BAT. Data from 1040 normal adults and 328 children were included in the final analysis, which showed that the normal range is 0-3 for adult males, 0-5 for adult females and 0-2 in children for both males and females. Therefore, the cut-off for a positive or abnormal BS is ≥4 in adult males, ≥6 in adult females and ≥3 in children. This information can now be used to objectively assess bleeding symptoms as normal or abnormal in future studies.