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

Utility of Global Hemostatic Assays in Patients with Bleeding Disorders of Unknown Cause

Bleeding disorder of unknown cause (BDUC) is a diagnosis of exclusion after exhaustive evaluation of plasmatic coagulation and platelet function. This review explores the utility of global hemostatic assays as confirmatory tests and in elucidating the pathophysiology of BDUC. Unlike traditional hemostatic tests that focus on coagulation factors, global assays are conducted both in plasma and also whole blood. These assays provide a more comprehensive understanding of the cell-based model of coagulation, aid in the identification of plasmatic factor abnormalities that may reduce hemostatic capacity, and allow for the assessment of impaired platelet-endothelial interactions under shear stress, as well as hyperfibrinolytic states. While clinical tests such as skin bleeding time and global assays such as PFA-100 exhibit limited diagnostic capacity, the role of viscoelastic testing in identifying hemostatic dysfunction in patients with BDUC remains unclear. Thrombin generation assays have shown variable results in BDUC patients; some studies demonstrate differences compared with healthy controls or reference values, whereas others question its clinical utility. Fibrinolysis assessment in vitro remains challenging, with studies employing euglobulin clot lysis time, plasma clot lysis time, and fluorogenic plasmin generation yielding inconclusive or conflicting results. Notably, recent studies suggest that microfluidic analysis unveils shear-dependent platelet function defects in BDUC patients, undetected by conventional platelet function assays. Overall, global assays might be helpful for exploring underlying hemostatic impairments, when conventional hemostatic laboratory tests yield no results. However, due to limited data and/or discrepant results, further research is needed to evaluate the utility of global assays as screening tools.

Periprocedural hemostatic prophylaxis and outcomes in bleeding disorder of unknown cause

Background

Bleeding disorder of unknown cause (BDUC) is a diagnostic category encompassing patients with a clear bleeding phenotype but without identifiable abnormality on hemostatic testing. The optimal management of hemostasis in BDUC patients prior to invasive procedures and childbirth is uncertain.

Objectives

Our objective was to characterize periprocedural hemostatic prophylaxis and bleeding outcomes in patients with BDUC.

Methods

We conducted a retrospective cohort study of adult patients with BDUC at 2 academic medical centers. Following diagnosis of BDUC, subsequent surgical procedures and childbirths were analyzed using a combination of registry data and manual chart review.

Results

We identified 127 patients with mean age of 39.9 years (SD = 16.6); the majority of patients were female (91.3%). Forty-eight major procedures, 70 minor procedures, and 19 childbirths were analyzed. Antifibrinolytic monotherapy was advised for 57% of major procedures, 59% of minor procedures, and 67% of childbirths. Perioperative platelet transfusion was recommended in 26% of major procedures and 9% of minor procedures in combination with other hemostatic agents. Major or clinically relevant nonmajor bleeding occurred in 4.1% (4/98) of procedures with prophylaxis and 10% (2/20) of procedures without prophylaxis. Postpartum hemorrhage occurred in 26% (5/19) of deliveries.

Conclusion

In this multiinstitution experience, we found overall low rates of hemostatic complications in procedures completed with hemostatic prophylaxis, although preventing hemorrhage in childbirth and gynecologic procedures remain unmet needs.

Examining variability in the diagnosis and management of people with bleeding disorders of unknown cause: communication from the ISTH SSC Subcommittee on von Willebrand Factor

BACKGROUND

Bleeding disorder of unknown cause (BDUC) is characterized by a bleeding phenotype in the setting of normal hemostatic testing. No standardized diagnostic criteria or treatment algorithms exist for people with BDUC. To address the unmet need, the International Society on Thrombosis and Haemostasis von Willebrand Factor Scientific Subcommittee performed a real-world survey aimed at addressing knowledge gaps, developing consensus pathways, and ultimately improving care.

OBJECTIVES

We sought to determine current international clinical practices in the investigation, registration, and treatment of people with BDUC internationally.

METHODS

An online structured survey was conducted of healthcare providers who managed patients with bleeding disorders using the ISTH RedCap tool.

RESULTS

Two hundred sixteen respondents from 39 countries were included in the final analysis. The clinical assessment of those with a possible bleeding disorder varied, with only 55% excluding hypermobility but high levels (80%) of bleeding assessment tool usage. In hemostatic testing, only the prothrombin time and activated partial thromboplastin time tests gained universal support. Tranexamic acid was favored for prophylaxis for minor (71%)/major (59%) surgeries and pregnancy (58%), but advice on the treatment if bleeding occurred was heterogeneous. The management of heavy menstrual bleeding in women despite combined oral contraceptive pill use also proved challenging, with healthcare providers selecting multiple alternative strategies.

CONCLUSION

Significant variation exists in the recognition, registration, and management of people with BDUC worldwide. This survey emphasizes the need for consensus pathways to diagnose and treat BDUC to standardize and improve care for patients internationally.

Does the VWF:CB Assay Help to Diagnose von Willebrand Factor Deficiency in Patients With a Bleeding Disorder of Unknown Cause?

INTRODUCTION

The entity entitled bleeding disorder of unknown cause (BDUC) qualifies individuals displaying a mild haemorrhagic profile but normal routine coagulation tests. This study was designed to evaluate whether collagen-binding assay for von Willebrand Factor (VWF) measurement (VWF:CB) could allow to diagnose VW disease in such patients.

METHODS

A large screening was conducted prospectively in two University Hospitals, using the bleeding assessment tool (BAT) recommended by the International Society of Thrombosis and Hemostasis. Patients with an abnormal BAT were confirmed to have a normal complete hemostatic evaluation. A large range of VWF assays was then carried out on a new blood sample for the 68 individuals (91% women) thus identified. Of note, five VWF:CB using different types of collagen were performed, as well as a comprehensive sequencing of the VWF gene.

RESULTS

Of this cohort, only 3 individuals (all blood group O), had a VWF:CB between 40 and 50 IU/dL. No unknown anomaly of the VWF gene was disclosed. Of note, 54% of these patients had unexplained abnormal occlusion times on PFA-200.

CONCLUSION

This study identified 68 cases of BDUC, after screening of a large population, indicating a low incidence. Only 3 cases were potentially confirmed as displaying moderate von Willebrand disease. VWF:CB tests were globally normal in the 65 other patients of the cohort.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT0279220.

Bleeding Disorder of Unknown Cause: A Diagnosis of Exclusion

Patients with an unexplained mild to moderate bleeding tendency are diagnosed with bleeding disorder of unknown cause (BDUC), a classification reached after ruling out other mild to moderate bleeding disorders (MBD) including von Willebrand disease (VWD), platelet function defects (PFDs), coagulation factor deficiencies (CFDs), and non-hemostatic causes for bleeding. This review outlines our diagnostic approach to BDUC, a diagnosis of exclusion, drawing on current guidelines and insights from the Vienna Bleeding Biobank (VIBB). According to guidelines, we diagnose VWD based on VWF antigen and/or activity levels ≤50 IU/dL, with repeated VWF testing if VWF levels are <80 IU/dL. This has been introduced in our clinical routine after our findings of diagnostically relevant fluctuations of VWF levels in a high proportion of MBD patients. PFDs are identified through repeated abnormalities in light transmission aggregometry (LTA), flow cytometric mepacrine fluorescence, and glycoprotein expression analysis. Nevertheless, we experience diagnostic challenges with regard to reproducibility and unspecific alterations of LTA. For factor (F) VIII and FIX deficiency, a cutoff of 50% is utilized to ensure detection of mild hemophilia A or B. We apply established cutoffs for other rare CFD being aware that these do not clearly reflect the causal role of the bleeding tendency. Investigations into very rare bleeding disorders due to hyperfibrinolysis or increase in natural anticoagulants are limited to cases with a notable family history or distinct bleeding phenotypes considering cost-effectiveness. While the pathogenesis of BDUC remains unknown, further explorations of this intriguing area may reveal new mechanisms and therapeutic targets.

Standardization of definition and management for bleeding disorder of unknown cause: communication from the SSC of the ISTH

In many patients referred with significant bleeding phenotype, laboratory testing fails to define any hemostatic abnormalities. Clinical practice with respect to diagnosis and management of this patient cohort poses significant clinical challenges. We recommend that bleeding history in these patients should be objectively assessed using the International Society on Thrombosis and Haemostasis (ISTH) bleeding assessment tool. Patients with increased bleeding assessment tool scores should progress to hemostasis laboratory testing. To diagnose bleeding disorder of unknown cause (BDUC), normal complete blood count, prothrombin time, activated partial thromboplastin time, thrombin time, von Willebrand factor antigen, von Willebrand factor function, coagulation factors VIII, IX, and XI, and platelet light transmission aggregometry should be the minimum laboratory assessment. In some laboratories, additional specialized hemostasis testing may be performed to identify other rare causes of bleeding. We recommend that patients with a significant bleeding phenotype but normal laboratory investigations should be registered with a diagnosis of BDUC in preference to other terminology. Global hemostatic tests and markers of fibrinolysis demonstrate variable abnormalities, and their clinical significance remains uncertain. Targeted genomic sequencing examining candidate hemostatic genes has a low diagnostic yield. Underlying BDUC should be considered in patients with heavy menstrual bleeding since delays in diagnosis often extend to many years and negatively impact quality of life. Treatment options for BDUC patients include tranexamic acid, desmopressin, and platelet transfusions.

Utility of the international society on thrombosis and hemostasis-bleeding assessment tool in the diagnosis of patients who suspected of platelet function disorders

The ISTH-BAT is a structured bleeding assessment tool to record and help diagnose patients with possible bleeding disorders. However, a few studies evaluated the utility of ISTH-BAT in diagnosing patients with platelet function defects (PFDs). In this study, we evaluated the diagnostic utility of ISTH-BAT in predicting PFDs among patients suspected of PFDs. Forty patients suspected of PFDs and 21 normal healthy controls were evaluated by the ISTH-BAT scoring system, light transmission aggregometry (LTA), ATP-releasing assays (lumi-aggregometry), and expression of CD62P for diagnosis of PFDs. Among 40 patients suspected of PFDs, 10 were diagnosed as PFDs using lumiaggregometry and CD62P. The ISTH-BAT score in patients suspected of PFDs [(6, interquartile range (IQR) 1-8] and patients with PFDs was significantly higher than the control group (0; IQR 0-0) ( P  < 0.001). Receiver operating characteristic curves indicate that ISTH-BAT is not able to discriminate patients with PFDs from those without PFDs (areas under the curve of 0.620 (95% confidence interval 0.415-0.825). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the ISTH-BAT in predicting the presence of PFDs, respectively, were 40, 73.3, 33.3, and 78.6% in the cut-off ISTH-BAT at least 4 in adult men, at least 6 in adult women, and at least 3 in children (age < 18). The ISTH-BAT scoring system has good discriminatory power in diagnosing patients with PFDs from healthy controls but is ineffective in differentiating them from those without PFDs.

Platelet mechanosensing as key to understanding platelet function

PURPOSE OF REVIEW

This review highlights how the perception of platelet function is evolving based on recent insights into platelet mechanobiology.

RECENT FINDINGS

The mechanosensitive ion channel Piezo1 mediates activation of free-flowing platelets under conditions of flow acceleration through mechanisms independent of adhesion receptors and classical activation pathways. Interference with the initiation of platelet migration or with the phenotypic switch of migrating platelets to a procoagulant state aggravates inflammatory bleeding. Mechanosensing of biochemical and biophysical microenvironmental cues during thrombus formation feed into platelet contractile force generation. Measurements of single platelet contraction and bulk clot retraction show promise to identify individuals at risk for hemorrhage.

SUMMARY

New findings unravel novel mechanotransduction pathways and effector functions in platelets, establishing mechanobiology as a pivotal component of platelet function. These insights highlight limitations of existing treatments and offer new potential therapeutic approaches and diagnostic avenues based on mechanobiological principles. Further extensive research is required to distinguish between core hemostatic and pathological mechanisms influenced by platelet mechanosensing.

Investigating patients for bleeding disorders when most of the "usual" ones have been ruled out

A State of the Art lecture titled "Investigating Patients for Bleeding Disorders When Most of the Usual Ones Have Been Ruled Out" was presented at the International Society on Thrombosis and Haemostasis Congress in 2023. Mild to moderate bleeding disorders (MBDs) in patients in whom no diagnosis of an established disorder, such as platelet function defect, von Willebrand disease, or a coagulation factor deficiency, can be identified are classified as bleeding disorders of unknown cause (BDUCs). Prospective data from the Vienna Bleeding Biobank and other studies have revealed a high proportion of BDUCs of up to 70% among patients with MBD who have a similar bleeding phenotype as other MBDs. As BDUC is a diagnosis of exclusion, the accuracy of the diagnostic workup is essential. For example, repeated testing for von Willebrand disease should be considered if von Willebrand factor values are <80 IU/dL. Current evidence does not support the clinical use of global assays such as thromboelastography, platelet function analyzer, or thrombin generation potential. Rare and novel bleeding disorders due to genetic variants in fibrinolytic factors or natural anticoagulants are rare and should only be analyzed in patients with specific phenotypes and a clear family history. In BDUC, blood group O was identified as a risk factor for increased bleeding severity and bleeding risk after hemostatic challenges. Future studies should improve the phenotypical characterization and ideally identify novel risk factors in BDUC, as a multifactorial pathogenesis is suspected. Finally, we summarize relevant new data on this topic presented during the 2023 International Society on Thrombosis and Haemostasis Congress.

Bleeding disorder of unknown cause: Results from Iranian study

BACKGROUND

Definite diagnosis of patients with mild to moderate bleeding is challenging. Some studies reported that even more than 50% of their patients remained undiagnosed which is classified as a Bleeding disorder of unknown cause (BDUC). This study aims to document the clinical characteristics and proportion of patients with BDUC in the Iranian Comprehensive Hemophilia Care Center (ICHCC) one of the referral centers for diagnosis of congenital bleeding disorder in Iran.

METHODS

This study was conducted on 397 patients who were referred with a bleeding manifestation to ICHCC from 2019 to 2022. Demographic and laboratory data were documented for all patients. Bleeding questionnaires including ISTH-Bleeding Assessment tool (ISTH-BAT) and the Molecular and Clinical Markers for the Diagnosis and Management of Type 1 (MCMDM-1 (ISTH-BAT, MCMDM-1, and the Pictorial Bleeding Assessment Chart (PBLAC) were filled out for all patients. The data were analyzed by the statistical package for social science (SPSS version 22, SPSS, Chicago, Illinois, USA).

RESULTS

BDUC was diagnosed in 200 patients and 197 patients reached the final diagnosis. Hemophilia, von Willebrand disease (VWD), factor (F) VII deficiency, and platelet functional disorders (PFDs) were confirmed in 54, 49, 34, and 15 of the patients, respectively. No significant difference was found in bleeding scores between patients with BDUC and those with confirmed disease. In contrast, after setting cut-off (ISTH-BAT for males ≥ 4 and females ≥ 6 and MCMDM-1 for males ≥ 3 and females ≥ 5) clinically significant difference was found. There was no association between having a positive consanguineous marriage and setting a diagnosis; however, significant associations were seen for having a positive family history of bleeding. Age (OR =0.977, 95% CI.965-0.989), gender (BDUC female, 151/200; final diagnosis female, 95/197) (OR=3.3, 95% CI 2.16-5.06), family history (OR = 3.19, 95% CI 1.99-5.11), and consanguineous marriage (OR=1.59, 95% CI 1.03-2.45) were considered as a risk factor for categorizing the patients with BDUC or final diagnosis.

CONCLUSION

The findings are mainly in line with previous studies about BDUC patients. The large number of patients with BDUC underlines the incompleteness of available routine laboratory tests and shows the necessity of progress in the development of reliable diagnostic tools to identify underlying bleeding disorders.

Clinicopathological Parameters of Haemophilia Patients at a Tertiary Care Centre in Northern India

INTRODUCTION

Haemophilia affects a large number of people all over the world, yet very little is known about the clinical manifestations and diagnostic protocols of the condition in areas with limited access to resources in developing countries. Understanding the clinical spectrum and diagnostic approach will help with the design of measures to address the situation in these places. The primary objective of this study was to examine the clinicopathological parameters of haemophiliac patients.

MATERIALS AND METHODS

From the departmental archive, a thorough history of each patient was retrieved, including values of bleeding time, prothrombin time, activated partial prothrombin time, and percentage of specific factor activity.

RESULTS

Out of a total of 385 cases over the period of six years, 86.75% were classified as haemophilia A and 13.25% of cases were diagnosed as haemophilia B. In terms of the severity of the disease, 44.93% were classified as severe, 42.08% as moderate, and 12.99% as mild. Joint bleeding was the first and most typical clinical manifestation of the disease, accounting for 34.80% of cases, followed by ecchymosis (23.12%), post-traumatic bleeding (12.73%), epistaxis (12.20%), and gum bleeding (8.05%). 1.56% of patients had a positive screening test for the hepatitis C virus, followed by 1.30% for HIV and 0.78% for hepatitis B surface antigen.

CONCLUSION

In the presence of joint bleeding, ecchymosis, and post-traumatic bleeding in an otherwise healthy individual, a clinician should be alerted to the possibility that the patient has haemophilia and should request a work-up for the bleeding disorder.

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

INTRODUCTION

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

AREA COVERED

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

EXPERT OPINION

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

Risk factors for future bleeding in patients with mild bleeding disorders: longitudinal data from the Vienna Bleeding Biobank

BACKGROUND

The future bleeding risk, especially after hemostatic challenges, and thus the requirement for hemostatic treatment in patients with mild-to-moderate bleeding disorders (MBDs) is largely unknown.

OBJECTIVES

This study aimed to prospectively examine the recurrence of bleeding symptoms and clinical risk factors for future bleeding in patients with MBD, including patients with bleeding disorder of unknown cause (BDUC).

METHODS

Bleeding symptoms of patients with MBD included in the Vienna Bleeding Biobank were re-evaluated at in-person follow-up visits or by mail.

RESULTS

In total, 392 patients, including 62.8% with BDUC, were investigated for the recurrence of bleeding events. During the follow-up time of median (IQR) 4.3 years (2.6-6.7), 72% of patients had at least 1 bleeding event. Most persistent bleeding manifestations were hematomas (n = 146/245, 59.6%) and bleeding from small wounds (n = 69/141, 48.9%), followed by epistaxis (n = 42/132, 31.8%), oral mucosal bleeding (n = 26/87, 29.9%), and joint bleeding (n = 7/14, 50.0%). Patients with previous postinterventional bleeding had a significantly increased risk for bleeding events after surgery (n = 33/114, 29.0 %) or tooth extraction (n = 16/39, 41.0%). A high bleeding score (OR [95% CI], 1.14 [1.05 to 2.94], per 1 unit) and follow-up time (OR [95% CI], 1.23 [1.12 to 1.36], per 1 year) were independently associated with any bleeding event. For bleeding after hemostatic challenges, blood group O (OR, 3.17 [1.57 to 6.40]), previous postsurgical bleeding (OR, 2.40 [1.06 to 5.46]), and an established diagnosis (OR, 2.07 [1.04 to 4.10]) were independent risk factors.

CONCLUSION

Patients with MBD have a high risk for recurrent bleeding. This encourages prophylactic hemostatic treatment in patients with MBD, particularly when they face hemostatic challenges.

A polymer-based systemic hemostat for managing uncontrolled bleeding

Uncontrolled bleeding is a life-threatening emergency that requires immediate intervention. Currently available on-site bleeding interventions largely rely on the use of tourniquets, pressure dressing, and other topical hemostatic agents, which can only treat bleeding injuries that are known, accessible, and potentially compressible. Synthetic hemostats that are stable at room temperature, easy to carry, field-usable, and able to stop internal bleeding at multiple or unknown sources, are still lacking. We recently developed a hemostatic agent via polymer peptide interfusion (HAPPI), which can selectively bind to activated platelets and injury sites after intravascular administration. Here we report that HAPPI is highly effective in treating multiple lethal traumatic bleeding conditions in normal as well as hemophilia models via either systemic administration or topical application. In a rat liver traumatic model, intravenous injection of HAPPI resulted in a significant decrease in blood loss and a four-fold reduction in mortality rate within 2 h after injury. When applied topically on liver punch biopsy wounds in heparinized rats, HAPPI achieved a 73% of reduction in blood loss and a five-fold increase in survival rate. HAPPI also exhibited hemostatic efficacy in hemophilia A mice by reducing blood loss. Further, HAPPI worked synergistically with rFVIIa to induce immediate hemostasis and 95% reduction in total blood loss compared to the saline-treated group in hemophelia mice models. These results demonstrate that HAPPI is a promising field-usable hemostatic agent for a broad range of different hemorrhagic conditions.

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

BACKGROUND

Excessive or abnormal mucocutaneous bleeding (MCB) may impact all aspects of the physical and psychosocial wellbeing of those who live with it (PWMCB). The evidence base for the optimal diagnosis and management of disorders such as inherited platelet disorders, hereditary hemorrhagic telangiectasia (HHT), hypermobility spectrum disorders (HSD), Ehlers-Danlos syndromes (EDS), and von Willebrand disease (VWD) remains thin with enormous potential for targeted research.

RESEARCH DESIGN AND METHODS

National Hemophilia Foundation and American Thrombosis and Hemostasis Network initiated the development of a National Research Blueprint for Inherited Bleeding Disorders with extensive all-stakeholder consultations to identify the priorities of people with inherited bleeding disorders and those who care for them. They recruited multidisciplinary expert working groups (WG) to distill community-identified priorities into concrete research questions and score their feasibility, impact, and risk.

RESULTS

WG2 detailed 38 high priority research questions concerning the biology of MCB, VWD, inherited qualitative platelet function defects, HDS/EDS, HHT, bleeding disorder of unknown cause, novel therapeutics, and aging.

CONCLUSIONS

Improving our understanding of the basic biology of MCB, large cohort longitudinal natural history studies, collaboration, and creative approaches to novel therapeutics will be important in maximizing the benefit of future research for the entire MCB community.

Effectiveness and costs of a stepwise versus an all-in-one approach to diagnose mild bleeding disorders

The diagnostic work-up of patients referred to the haematologist for bleeding evaluation is performed in a stepwise way: bleeding history and results of screening laboratory tests guide further diagnostic evaluation. This can be ineffective, time-consuming and burdensome for patients. To improve this strategy, the initial laboratory investigation can be extended. In a model-based approach, effectiveness and costs of a conventional stepwise versus a newly proposed all-in-one diagnostic approach for bleeding evaluation were evaluated and compared, using data from an observational patient cohort study, including adult patients referred for bleeding evaluation. In the all-in-one approach, specialized platelet function tests, coagulation factors, and fibrinolysis tests were included in the initial investigation. Final diagnosis, hospital resource use and costs and patient burden were compared. A total of 150 patients were included. Compared to the stepwise approach, in the all-in-one approach, 19 additional patients reached a diagnosis and patient burden was lower, but total costs per patient were higher [€359, 95% bootstrapped confidence interval (BCI) 283-518, p = 0.001]. For bleeding evaluation of patients referred to the haematologist, an all-in-one diagnostic approach has a higher diagnostic yield and reduces patient burden, at a higher cost. This raises the question what costs justify the diagnosis of a bleeding disorder and a less burdensome diagnostic strategy.

Novel Approach to Improve the Identification of the Bleeding Phenotype in Noonan Syndrome and Related RASopathies

OBJECTIVES

To characterize bleeding phenotype in Noonan Syndrome, to test the utility of following national guidelines in detecting this phenotype, to evaluate thromboelastography (TEG) as a diagnostic tool and to evaluate the cohort for genotype-phenotype correlations.

STUDY DESIGN

Participants with a clinical diagnosis NS or related RASopathy were enrolled in a cohort study. Study procedures included clinical bleeding assessment, coagulation testing per guidelines and hematology consultation. TEG was completed in a subset and genetic testing was conducted for those without a molecular diagnosis. International Society of Haemostasis and Thrombosis Bleeding Assessment Tool (ISTH-BAT) scores were calculated with hematology consultation. Bleeding phenotype was defined as abnormal bleeding score.

RESULTS

Twenty participants enrolled; 12completed clinical and laboratory evaluation, five of whom met the definition for bleeding phenotype. Four of the five participants with a bleeding phenotype had platelet aggregation defects and at least one additional coagulation defect. TEG was performed in nine participants, four with bleeding phenotype and five without, and results were normal in all cases. No genotype-phenotype correlation was found.

CONCLUSION

Five of 20 participants had a bleeding phenotype identified. Based on available data we do not recommend incorporating TEG into clinical practice for NS patients. Platelet aggregation defects were the most common abnormalities, which would not be detected on Tier 1 testing of current guidelines, therefore we propose a new algorithm.

Outcomes and management of pregnancy in women with bleeding disorder of unknown cause

BACKGROUND

Patients with a bleeding tendency with normal laboratory tests have been described as having an unclassified bleeding disorder or bleeding disorder of unknown cause (BDUC). There are very little data available on how to manage pregnancy.

OBJECTIVES

To study management and outcomes of these patients at four United Kingdom hemophilia comprehensive care centers.

METHODS

Retrospective case note review from 2010-2020.

RESULTS

Sixty deliveries in 36 patients were recorded. The median International Society on Thrombosis and Haemostasis bleeding assessment tool score was 9. In 54 cases for which data were available, the odds ratio for post partum hemorrhage (PPH) was 6.3 for no primary hemostatic prophylaxis versus prophylaxis (95% confidence interval 1.2-34.2, p < .05); 7/9 (78%) versus 16/45 (36%) PPH incidence for the groups, respectively. Hemostatic prophylaxis was with tranexamic acid but some patients received desmopressin or platelet infusions. Secondary PPH was seen in 5/60 (8%) of cases. No neonatal bleeding complications or maternal thromboembolic complications were noted. Avoidance of regional anesthesia and fetal delivery precautions were commonly advised, but in the small number of cases in which they occurred no complications were noted.

CONCLUSIONS

Despite hemostatic prophylaxis PPH was commonly seen. Further prospective studies of BDUC patients are required to determine optimal management in pregnancy as well as determine the pathophysiological basis of bleeding.

Prevalence of Heavy Menstrual Bleeding and Its Associated Cognitive Risks and Predictive Factors in Women With Severe Mental Disorders

There has been limited studies examining treatment-induced heavy menstrual bleeding (HMB) in women with severe mental illnesses. The aim of this study was to examine HMB prevalence and HMB-associated factors in young women (18–34 years old) diagnosed with bipolar disorder (BP), major depressive disorder (MDD), or schizophrenia (SCZ) who have full insight and normal intelligence. Eighteen-month menstruation histories were recorded with pictorial blood loss assessment chart assessments of HMB. Multivariate analyses were conducted to obtain odds ratios (ORs) and 95% confidence intervals (CIs). Drug effects on cognition were assessed with the MATRICS Consensus Cognitive Battery (MCCB). HMB prevalence were: BP, 25.85%; MDD, 18.78%; and SCH, 13.7%. High glycosylated hemoglobin (HbA1c) level was a strong risk factor for HMB [BP OR, 19.39 (16.60–23.01); MDD OR, 2.69 (4.59–13.78); and SCZ OR, 9.59 (6.14–12.43)]. Additional risk factors included fasting blood sugar, 2-h postprandial blood glucose, and use of the medication valproate [BP: OR, 16.00 (95%CI 12.74–20.22); MDD: OR, 13.88 (95%CI 11.24–17.03); and SCZ OR, 11.35 (95%CI 8.84–19.20)]. Antipsychotic, antidepressant, and electroconvulsive therapy use were minor risk factors. Pharmacotherapy-induced visual learning impairment was associated with HMB [BP: OR, 9.01 (95%CI 3.15–13.44); MDD: OR, 5.99 (95%CI 3.11–9.00); and SCZ: OR, 7.09 (95%CI 2.99–9.20)]. Lithium emerged as a protective factor against HMB [BP: OR, 0.22 (95%CI 0.14–0.40); MDD: OR, 0.30 (95%CI 0.20–0.62); and SCZ: OR, 0.65 (95%CI 0.33–0.90)]. In SCZ patients, hyperlipidemia and high total cholesterol were HMB-associated factors (ORs, 1.87–2.22). Psychiatrist awareness of HMB risk is concerningly low (12/257, 2.28%). In conclusion, prescription of VPA should be cautioned for women with mental illness, especially BP, and lithium may be protective against HMB.

Utility of International Society on Thrombosis and Hemostasis Bleeding Assessment Tool (ISTH-BAT) in Patients with Inherited Bleeding Disorders: A Cross-Sectional Study from Southern India

The International Society on Thrombosis and Hemostasis bleeding assessment tool (ISTH-BAT) was developed to record bleeding symptoms and aid in patient diagnosis. This study was done to investigate the utility of ISTH-BAT in patients suspected to have inherited bleeding disorders. This cross-sectional study was conducted in a tertiary care hospital in Southern India over 3 and 1/2 years. A trained investigator administered the ISTH-BAT questionnaire to 432 patients undergoing evaluation for inherited bleeding disorder prior to routine coagulation screening and confirmatory tests and to 131 healthy volunteers as controls. Among patients, 42(9.7%) had primary hemostatic defect, 150(34.7%) had secondary hemostatic defects and 229(53%) had normal screening coagulogram with mean bleeding scores (BS) being 5.9, 6.9, and 4.2 respectively and the proportion of patients with abnormal BS being 69%, 88.7% and 59.4% respectively; the latter qualifying as unknown hemostatic defect. 11(2.5%) with acquired hemostatic defect on workup were excluded. The mean BS was 1.52 among healthy volunteers. Common bleeding patterns were epistaxis (73.8%), cutaneous bleeding (52.4%), hematuria (54.8%), menorrhagia (50%) in primary hemostatic defect; cutaneous bleeding (72%), muscle hematoma (58.7%), hemarthrosis (46.7%), menorrhagia (58.7%) in secondary hemostatic defects and epistaxis (45.9%), cutaneous bleeding (62.4%), menorrhagia (30.7%) in normal screening coagulogram group. Grade of bleeding was mostly 2 and sometimes 4 in primary, 2-4 in secondary and 1-2 in normal screening coagulogram group. ISTH-BAT is a valuable tool to record lifelong bleeding history. The pattern and score give clues regarding the nature and severity of the bleeding disorder.

Risk-to-befit ratios of consecutive antidepressants for heavy menstrual bleeding in young women with bipolar disorder or major depressive disorder

The occurrence of heavy menstrual bleeding (HMB) induced by pharmacological agents has been reported in young adult women. This study aimed to investigate a possible association between the occurrence rates of HMB and different treatment methods such as antidepressant agents alone and in combination with other pharmacological agents. The examined cohort included young women (age 18-35 years, n = 1,949) with bipolar disorder (BP) or major depressive disorder (MDD). Menstruation history for 24 months was recorded and evaluated according to pictorial blood loss assessment charts of HMB. Multivariate analyses were conducted to determine odds ratios (ORs) and 95% confidence intervals. The examined antidepressant agents had varying ORs for patients with BP vs. those with MDD. For example, the ORs of venlafaxine-induced HMB were 5.27 and 4.58 for patients with BP and MDD, respectively; duloxetine-induced HMB, 4.72 and 3.98; mirtazapine-induced HMB, 3.26 and 2.39; fluvoxamine-induced HMB, 3.11 and 2.08; fluoxetine-induced HMB, 2.45 and 1.13; citalopram-induced HMB, 2.03 and 1.25; escitalopram-induced HMB, 1.85 and 1.99; agomelatine-induced HMB, 1.45 and 2.97; paroxetine-induced HMB, 1.19 and 1.75; sertraline-induced HMB, 0.88 and 1.13; reboxetine-induced HMB, 0.45 and 0.45; and bupropion-induced HMB, 0.33 and 0.37, in each case. However, when antidepressant agents were combined with valproate, the OR of HMB greatly increased, with distinct profiles observed for patients with BP vs. those with MDD. For example, the ORs of HMB induced by venlafaxine combined with valproate were 8.48 and 6.70 for patients with BP and MDD, respectively; for duloxetine, 5.40 and 4.40; mirtazapine, 5.67 and 3.73; fluvoxamine, 5.27 and 3.37; fluoxetine, 3.69 and 4.30; citalopram, 5.88 and 3.46; escitalopram, 6.00 and 7.55; agomelatine, 4.26 and 5.65; paroxetine, 5.24 and 3.25; sertraline, 4.97 and 5.11; reboxetine, 3.54 and 2.19; and bupropion, 4.85 and 3.46, in each case. In conclusion, some antidepressant agents exhibited potential risks of inducing HMB. Therefore, a combined prescription of antidepressant agents and valproate should be carefully considered for young women with HMB.

Cryptogenic oozers and bruisers

Bleeding disorders with normal, borderline, or nondiagnostic coagulation tests represent a diagnostic challenge. Disorders of primary hemostasis can be further evaluated by additional platelet function testing modalities, platelet electron microscopy, repeat von Willebrand disease testing, and specialized von Willebrand factor testing beyond the usual initial panel. Secondary hemostasis is further evaluated by coagulation factor assays, and factor XIII assays are used to diagnose disorders of fibrin clot stabilization. Fibrinolytic disorders are particularly difficult to diagnose with current testing options. A significant number of patients remain unclassified after thorough testing; most unclassified patients have a clinically mild bleeding phenotype, and many may have undiagnosed platelet function disorders. High-throughput genetic testing using large gene panels for bleeding disorders may allow diagnosis of a larger number of these patients in the future, but more study is needed. A logical laboratory workup in the context of the clinical setting and with a high level of expertise regarding test interpretation and limitations facilitates a diagnosis for as many patients as possible.

Current practice and registration patterns among United Kingdom Haemophilia Centre Doctors' Organisation centers for patients with unclassified bleeding disorders

BACKGROUND

Bleeding of unknown cause (BUC) and unclassified bleeding disorders (UBD) are increasingly recognized. There is no guidance on diagnosis and management.

OBJECTIVES

To examine UK haemophilia centre registration patterns and current practice for UBD patients.

METHODS

In a two-step process, the UK National Haemophilia Database (NHD) was reviewed for registration patterns of UBD patients and a survey of UK haemophilia centers was conducted (January/February 2021) to capture current practice for diagnosis and management of patients with UBD.

RESULTS/DISCUSSION

Overall, registrations with the NHD for UBD patients has sharply risen from 2012 to 2020 and in 2019 accounted for 2.65% of registered patients. For the survey, the response rate was 52/67 (78%). Practice was widely variable; 35/52 (67%) centers register UBD; among these 35 centers, terminology included UBD (28 centers), undiagnosed bleeding disorder (four centers), and BUC (three centers); 34/52 (65%) centers use a formal bleeding assessment tool. For management of dental extraction and high bleeding risk surgery in a fictional UBD patient we found that tranexamic acid was widely used; however, beyond this a variety of hemostatic products were advised including blood products, recombinant factor VIIa/prothrombin complex concentrate, and desmopressin. There was general consensus (≈90%) on avoiding regional anesthesia in pregnancy, but no agreement on the need for fetal precautions to avoid bleeding at delivery (50% would advise these). There was a disparity of opinion on chemical thromboprophylaxis, and management of patients without prior hemostatic challenges and offspring of these patients.

CONCLUSION

This study provides a snapshot of current practice and real-world data in this area. Future studies need to address the gaps in evidence.

How I treat. Bleeding Disorder of Unknown Cause (BDUC)

Recent studies have demonstrated that only 30% of patients referred for assessment of a possible bleeding tendency will eventually be diagnosed with a mild bleeding disorder (MBD) such as von Willebrand disease (VWD) or platelet function defect (PFD). Rather, the majority of such patients will be diagnosed with Bleeding Disorder of Unknown Cause (BDUC). There remains an important unmet need to define consensus regarding the clinical and laboratory criteria necessary for a formal BDUC diagnosis. Nevertheless, BDUC already accounts for more than 10% of patients registered in some Haemophilia Comprehensive Care centres. Accumulating recent data suggest that BDUC is also being diagnosed with increasing frequency. Increased BAT scores are widely utilized to differentiate significant from trivial symptoms in patients with mucocutaneous bleeding. Objective assessment of bleeding phenotype using a standardised bleeding assessment tool (BAT) therefore represents a fundamental first step in the diagnosis of BDUC. Since BDUC is a diagnosis by exclusion, accurate quantification of bleeding phenotype is critical as this will be the primary determinant upon which a diagnosis of BDUC is reached. Importantly, BAT scores suggest that patients with BDUC display bleeding phenotypes comparable to those seen in patients with VWD or PFD respectively. Despite the prevalence of BDUC, diagnosis and management of these patients commonly pose significant clinical dilemmas. In this manuscript, we consider these challenges in the context of a number of typical case studies, discuss the available evidence and outline our approach to the management of these patients.