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.

Autoimmune Coagulation Factor X Deficiency as a Rare Acquired Hemorrhagic Disorder: A Literature Review.

Coagulation factor X (F10) amplifies the clotting reaction in the middle of the coagulation cascade, and thus F10 deficiency leads to a bleeding tendency. Isolated acquired F10 deficiency is widely recognized in patients with immunoglobulin light-chain amyloidosis or plasma cell dyscrasias. However, its occurrence as an autoimmune disorder is extremely rare. The Japanese Collaborative Research Group has been conducting a nationwide survey on autoimmune coagulation factor deficiencies (AiCFDs) starting in the last decade; we recently identified three patients with autoimmune F10 deficiency (AiF10D). Furthermore, an extensive literature search was performed, confirming 26 AiF10D and 28 possible cases. Our study revealed that AiF10D patients were younger than patients with other AiCFDs; AiF10D patients included children and were predominantly male. AiF10D was confirmed as a severe type of bleeding diathesis, although its mortality rate was not high. As AiF10D patients showed only low F10 inhibitor titers, they were considered to have nonneutralizing anti-F10 autoantibodies rather than their neutralizing counterparts. Accordingly, immunological anti-F10 antibody detection is highly recommended. Hemostatic and immunosuppressive therapies may help arrest bleeding and eliminate anti-F10 antibodies, leading to a high recovery rate. However, further investigation is necessary to understand the basic characteristics and proper management of AiF10D owing to the limited number of patients.

Late-onset hematological complications post COVID-19: An emerging medical problem for the hematologist.

Coronavirus disease 19 (COVID-19) is considered a multisystemic disease. Several studies have reported persistent symptoms or late-onset complications after acute COVID-19, including post-COVID-19 hematological disorders. COVID-19-induced coagulopathy, an immunothrombotic state, has been linked to thromboembolic and hemorrhagic events. Late-onset thrombocytopenia related to immune system dysregulation has also been reported as a rare manifestation post COVID-19. Close monitoring of laboratory dynamics is considered essential to identify timely abnormal values that need further investigation, providing supportive care whenever indicated. The role of hematologists is essential in terms of the multidisciplinary approach of long COVID-19. This review summarizes all the available evidence on post-acute COVID-19 hematological complications.

How I treat bleeding disorder of unknown cause.

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, most of these 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. Accumulating recent data suggest that BDUC is being diagnosed with increasing frequency. Objective assessment of bleeding phenotype using a standardized bleeding assessment tool (BAT) therefore represents a fundamental first step in the diagnosis of BDUC. Because BDUC is a diagnosis by exclusion, accurate quantification of bleeding phenotype is critical because this will be the primary determinant on 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. Despite the prevalence of BDUC, diagnosis and management of these patients commonly pose significant clinical dilemmas. 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.

Management of surgery, menorrhagia and child-birth for patients with unclassified bleeding disorders: a systematic review of cohort studies.

Unclassified bleeding disorders account for 2.6% of all new bleeding disorder registrations in the UK. The management of the bleeding phenotype associated with these disorders is poorly described. Systematic review and meta-analysis to determine the bleeding rates associated with tranexamic acid, desmopressin, platelet transfusion, plasma transfusion and recombinant activated factor VII, for patients with unclassified bleeding disorders undergoing surgery, childbirth or with menorrhagia. We searched for randomized controlled trials in MEDLINE, Embase, The Cochrane Central Register of Controlled Trials, PubMed, ISI Web of Science and the Transfusion Evidence Library from inception to 24 February 2020. Wherever appropriate, data were pooled using the metaprop function of STATA. Two studies with 157 participants with unclassified bleeding disorders were identified. The pooled risk of minor bleeding for patients undergoing surgery treated with peri-operative tranexamic acid was 11% (95% confidence interval 3--20%; n = 52; I2 = 0%); the risk for desmopressin and tranexamic acid in combination was 3% (95% confidence interval 0--7%; n = 71; I2 = 0%). There were no instances of major bleeding. In one procedure, 1 of 71 (1.4%), treated with a combination of desmopressin and tranexamic acid, the patient had a line-related deep vein thrombosis. There were too few patients treated to prevent postpartum haemorrhage or for menorrhagia to draw conclusions. The GRADE quality of evidence was very low suggesting considerable uncertainty over the results. However, both tranexamic acid, and the combination of tranexamic and desmopressin have high rates of haemostatic efficacy and have few adverse events. PROTOCOL REGISTRATION: PROSPERO CRD42020169727.

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.

Gene Therapy for Inherited Bleeding Disorders.

Decades of preclinical and clinical studies developing gene therapy for hemophilia are poised to bear fruit with current promising pivotal studies likely to lead to regulatory approval. However, this recent success should not obscure the multiple challenges that were overcome to reach this destination. Gene therapy for hemophilia A and B benefited from advancements in the general gene therapy field, such as the development of adeno-associated viral vectors, as well as disease-specific breakthroughs, like the identification of B-domain deleted factor VIII and hyperactive factor IX Padua. The gene therapy field has also benefited from hemophilia B clinical studies, which revealed for the first time critical safety concerns related to immune responses to the vector capsid not anticipated in preclinical models. Preclinical studies have also investigated gene transfer approaches for other rare inherited bleeding disorders, including factor VII deficiency, von Willebrand disease, and Glanzmann thrombasthenia. Here we review the successful gene therapy journey for hemophilia and pose some unanswered questions. We then discuss the current state of gene therapy for these other rare inherited bleeding disorders and how the lessons of hemophilia gene therapy may guide clinical development.

Acquired factor V inhibitor in the setting of coronavirus disease 2019 infection.

Factor V inhibitors are a rare cause of life-threatening bleeding. We present a case of an acquired factor V inhibitor likely caused by coronavirus disease 2019 infection. Bleeding was manifested by severe anemia requiring frequent red-cell transfusion, left psoas muscle hematoma, and left retroperitoneal cavity hematoma. Factor V activity was less than 1% and the factor V inhibitor titer was 31.6 Bethesda units. Severe acute respiratory syndrome coronavirus 2 RNA testing of the nasopharynx was positive 2 weeks before presentation and continued to be positive for 30 days. The patient failed treatment with intravenous immunoglobulin and dexamethasone. Three cycles of plasmapheresis with fresh frozen plasma replacement resulted in correction of the bleeding and laboratory coagulopathy. This is the first reported case of a factor V inhibitor in a coronavirus disease 2019 patient and suggests that plasmapheresis may be a successful treatment strategy.

Rare bleeding disorders and advances in gene therapy.

: Rare bleeding disorders usually begin in childhood and manifest as varying degrees of bleeding, which can be life-threatening in severe cases. With the development of gene editing technology, it is expected that hereditary coagulation factor disorders will someday be fundamentally cured by gene therapy. On account of their rarity, comprehension of these diseases is essential for the application of new treatment strategies. We have compiled the features of some newly discovered mutations of prothrombin, factor VII, and factor X in recent years. In addition, this review introduces the advances and obstacles in gene therapy.

The central role of thrombin in bleeding disorders.

Maintaining normal hemostasis relies on a regulated system of procoagulant and anticoagulant pathways, and disruption of these processes leads to the loss of hemostatic control, with the potential for excessive bleeding or thrombosis. Evaluation of bleeding disorders has conventionally been achieved by laboratory assays that measure the activity of individual coagulation factors. While such assays have proven effective for detecting abnormalities of the coagulation system and aiding diagnosis, inherent limitations prevent them from capturing a complete picture of hemostatic function. An improved understanding of thrombin activity and its central role in hemostasis and bleeding disorders has led to the clinical development of global assays that are more physiologically relevant than traditional assays; furthermore, these global assays are able to monitor responses to therapy. In this review, we provide an overview of the role of thrombin in hemostasis, and describe the clinical benefits of thrombin monitoring in patients with bleeding disorders. Moreover, we discuss recent advances in thrombin-targeting therapeutic strategies that aim to correct thrombin deficiency and prevent bleeding in patients with hemophilia and other rare bleeding disorders.

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

INTRODUCTION: Historically, issues faced by women with bleeding disorders (WBD) have been underestimated. While advances in genetic testing have resulted in improvements, significant challenges remain in the initial recognition of abnormal bleeding and referral of WBD. METHODS: The European Haemophilia Consortium (EHC) developed a questionnaire for WBD to provide insights into the barriers and challenges faced by WBD in Europe. RESULTS: In total, 709 WBD responded to the survey from 32 countries, predominantly from western European countries (94%). A delay in ascertaining the diagnosis of a congenital bleeding disorders (CBD) remains, with a median age at diagnosis of 16 years. The presence of family history is strongly associated with a lower median age at diagnosis of 6 years. WBD reported significant disease impact on their day-to-day life, most evident for the rarer CBD. The bleeding symptom of biggest impact on daily life is heavy menstrual bleeding (HMB), reported by 55% of women. Importantly, 25% of WBD reports that their condition severely impacted their decision to have or has prevented them from having children. Respondents registered with Haemophilia Treatment Centres (HTC) are 2.2 times more likely to receive treatment compared to WBD in other hospital services. CONCLUSION: Improved education for both patients and healthcare providers is essential to improve time to diagnosis, access to treatment and psychosocial supports for WBD in Europe.

Management of acute promyelocytic leukemia: updated recommendations from an expert panel of the European LeukemiaNet.

Since the comprehensive recommendations for the management of acute promyelocytic leukemia (APL) reported in 2009, several studies have provided important insights, particularly regarding the role of arsenic trioxide (ATO) in frontline therapy. Ten years later, a European LeukemiaNet expert panel has reviewed the recent advances in the management of APL in both frontline and relapse settings in order to develop updated evidence- and expert opinion-based recommendations on the management of this disease. Together with providing current indications on genetic diagnosis, modern risk-adapted frontline therapy, and salvage treatment, the review contains specific recommendations for the identification and management of the most important complications such as the bleeding disorder APL differentiation syndrome, QT prolongation, and other all-trans retinoic acid- and ATO-related toxicities, as well as recommendations for molecular assessment of the response to treatment. Finally, the approach to special situations is also discussed, including management of APL in children, elderly patients, and pregnant women. The most important challenges remaining in APL include early death, which still occurs before and during induction therapy, and optimizing treatment in patients with high-risk disease.

Bleeding Disorders in Adolescents with Heavy Menstrual Bleeding: The Queensland Statewide Paediatric and Adolescent Gynaecology Service.

STUDY OBJECTIVE: Heavy menstrual bleeding (HMB) is a common gynecological complaint among young women with up to 40% having experienced HMB. Bleeding disorders are increasingly being recognized in adolescents and young adults with HMB. The aim of this study was to determine the prevalence of bleeding disorders in adolescents with HMB, among patients who presented to the Queensland Statewide Paediatric and Adolescent Gynaecology Service between July 2007 and July 2017. DESIGN, SETTING, PARTICIPANTS, INTERVENTIONS, AND MAIN OUTCOME MEASURES: The study was a retrospective review of 124 female adolescents aged 8 to 18 years with HMB who presented to the Queensland Paediatric and Adolescent Gynaecology Service, Brisbane, Australia. The primary outcome measure was diagnosis of a bleeding disorder, with secondary outcomes including iron deficiency and/or anemia and treatment modalities. RESULTS: Screening for bleeding disorders was performed in 77/124 (62.1%) of patients with HMB. Twenty-seven adolescents were diagnosed with a bleeding disorder, giving a prevalence of 27/124 (21.7%) in those with HMB, and 27/77 (35%) with HMB who were screened. Of these 35%, von Willebrand disease was the most common bleeding disorder, found in 14/27 (51.6%), followed by inherited platelet function disorders diagnosed in 9/27 (33.3%), thrombocytopenia (inherited or acquired) in 3/27 (11.1%), and Factor IX deficiency in 1/27 (3.7%). Iron deficiency and/or anemia was diagnosed in 53/107 (49.5%) of patients with HMB who were screened for this, and 19/27 (70.3%) of those diagnosed with a bleeding disorder. CONCLUSION: Adolescents with HMB who present to a tertiary pediatric and adolescent gynecology service should be screened for bleeding disorders, because of the considerably high prevalence in this at-risk population.

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 the evaluation of such patients: 1) perform a clinical and laboratory evaluation for an underlying bleeding disorder based on 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, particulary 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 products daily 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 not only a hemoglobin, but also a ferritin level, when evaluating these patients. Iron supplementation is often a key component of management in the adolescent with heavy menses, and is still needed even in those who have received packed red cell transfusions due to severe anemia. Strategies for decreasing menstrual blood flow are similar between adults and adolescents with heavy menses, with combined hormonal contraceptives recommended as first-line therapy. However, adolescent-specific considerations exist for many of these agents, and must be incorporated into shared decision making when selecting the most appropriate treatment.