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Baker RI, Choi P, Curry N, Gebhart J, Gomez K, Henskens Y, Heubel-Moenen F, James P, Kadir RA, Kouides P, Lavin M, Lordkipanidze M, Lowe G, Mumford A, Mutch N, Nagler M, Othman M, Pabinger I, Sidonio R, Thomas W, O'Donnell JS. Standardization of definition and management for bleeding disorder of unknown cause: communication from the SSC of the ISTH. J Thromb Haemost 2024; 22:2059-2070. [PMID: 38518896 DOI: 10.1016/j.jtha.2024.03.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 02/08/2024] [Accepted: 03/08/2024] [Indexed: 03/24/2024]
Abstract
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.
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Affiliation(s)
- Ross I Baker
- Western Australia Centre for Thrombosis and Haemostasis, Murdoch University, Perth, Australia; Clinical Research Unit, Perth Blood Institute, Perth, Australia; Hollywood Hospital Haemophilia Centre, Haematology Academic Unit, Perth, Australia; Irish-Australian Blood Collaborative Network, Dublin, Ireland and Perth, Australia.
| | - Philip Choi
- Haematology Department, The Canberra Hospital, Canberra, Australia; Division of Genome Sciences and Cancer, John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Nicola Curry
- Department of Clinical Haematology, Haemophilia & Thrombosis Centre, Oxford University Hospitals National Health Service Foundation Trust, Oxford, United Kingdom; Radcliffe Department of Medicine, Oxford University, Oxford, United Kingdom
| | - Johanna Gebhart
- Department of Medicine, Division of Hematology and Hemostaseology, Medical University Vienna, Vienna, Austria
| | - Keith Gomez
- Katharine Dormandy Haemophilia Centre and Thrombosis Unit, Royal Free London National Health Service Foundation Trust, London, United Kingdom
| | - Yvonne Henskens
- Central Diagnostic Laboratory, Maastricht University Medical Centre, Maastricht, The Netherlands; Department of Biochemistry, Institute for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands
| | - Floor Heubel-Moenen
- Department of Hematology, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Paula James
- Department of Medicine, Queen's University, Kingston, Ontario, Canada
| | - Rezan Abdul Kadir
- Department of Obstetrics and Gynaecology, Katharine Dormandy Haemophilia and Thrombosis Centre, The Royal Free National Health Service Hospital, London, United Kingdom; Institute for Women's Health, University College, London, United Kingdom
| | - Peter Kouides
- Mary M. Gooley Hemophilia Center, Rochester, New York, USA
| | - Michelle Lavin
- Irish-Australian Blood Collaborative Network, Dublin, Ireland and Perth, Australia; National Coagulation Centre, St. James's Hospital, Dublin, Ireland; Irish Centre for Vascular Biology, School of Pharmacy & Biomolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Marie Lordkipanidze
- Research Center, Montreal Heart Institute, Montreal, Quebec, Canada; Faculty of Pharmacy, Université de Montréal, Montreal, Quebec, Canada
| | - Gillian Lowe
- West Midlands Adult Comprehensive Care Haemophilia Centre, University Hospitals Birmingham National Health Service Foundation Trust, Birmingham, United Kingdom
| | - Andrew Mumford
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Nicola Mutch
- Aberdeen Cardiovascular and Diabetes Centre, Institute of Medical Sciences, School of Medicine, United Kingdom; Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, United Kingdom
| | - Michael Nagler
- Department of Clinical Chemistry, Inselspital, Bern University Hospital, Bern, Switzerland; Department of Clinical Chemistry, Inselspital University Hospital Bern, Bern, Switzerland
| | - Maha Othman
- Department of Biomedical and Molecular Sciences, School of Medicine, Queen's University, Kingston, Ontario, Canada; School of Baccalaureate Nursing, St Lawrence College, Kingston, Ontario, Canada; Clinical Pathology Department, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Ingrid Pabinger
- Department of Medicine, Division of Hematology and Hemostaseology, Medical University Vienna, Vienna, Austria
| | - Robert Sidonio
- Emory University and Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Will Thomas
- Department of Haematology, Cambridge University Hospitals National Health Service Foundation Trust, Cambridge, United Kingdom
| | - James S O'Donnell
- Irish-Australian Blood Collaborative Network, Dublin, Ireland and Perth, Australia; National Coagulation Centre, St. James's Hospital, Dublin, Ireland; Irish Centre for Vascular Biology, School of Pharmacy & Biomolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
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Ariëns S, Huisman A, Hovinga ICLK, Urbanus RT, van Galen KPM, van Vulpen LFD, Fischer K, Schutgens REG. Limited value of testing for factor XIII and α2-antiplasmin deficiency in patients with a bleeding disorder of unknown cause. Haemophilia 2024. [PMID: 38812123 DOI: 10.1111/hae.15059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 05/14/2024] [Accepted: 05/20/2024] [Indexed: 05/31/2024]
Abstract
INTRODUCTION In patients with an increased bleeding tendency, extensive diagnostic blood testing is often performed. When results of tier 1 assays of primary haemostasis are normal, protocols recommend additional testing to rule out rare disorders including coagulation factor XIII (FXIII) and α2-antiplasmin (α2AP) deficiency. AIM To evaluate the added diagnostic value of FXIII and α2AP levels in patients with a bleeding disorder of unknown cause (BDUC). METHODS A retrospective monocentre cohort study between August 2011 and August 2023 was conducted. In all patients with bleeding tendencies and normal diagnostic tests for von Willebrand disease and platelet function, FXIII and α2AP were measured. RESULTS We included 158 consecutive patients; mean ISTH-BAT scores were 8.2 (SD ± 3.7) in children, 6.2 (SD ± 2.1) in men and 10.6 (SD ± 3.3) in women. Median age was 37 (range 5-79) years, 88.6% of patients were female. Patients displayed median FXIII activity of 111% (IQR = 97-131) and median α2AP activity of 112% (IQR = 103-119). Three (1.9%) patients had FXIII levels < 50%, respectively 43%, 45% and 46%. Corresponding ISTH-BAT scores were 7, 12 and 14. No α2AP levels < 60% was observed. No significant association was found between FXIII levels and ISTH-BAT scores. CONCLUSION In our cohort of BDUC patients, no clinical relevant FXIII deficiencies were detected; absolute values were well above the 30% cutoff considered adequate for normal haemostasis. No α2AP deficiencies were detected. These data suggest that in BDUC patients, measuring FXIII or AP activity is of limited value.
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Affiliation(s)
- Sander Ariëns
- Center for Benign Haematology, Thrombosis and Haemostasis, van Creveldkliniek, Utrecht, the Netherlands
| | - Albert Huisman
- Central Diagnostic Laboratory, University Medical Center Utrecht and University Utrecht, Utrecht, the Netherlands
| | - Idske C L Kremer Hovinga
- Center for Benign Haematology, Thrombosis and Haemostasis, van Creveldkliniek, Utrecht, the Netherlands
| | - Rolf T Urbanus
- Center for Benign Haematology, Thrombosis and Haemostasis, van Creveldkliniek, Utrecht, the Netherlands
| | - Karin P M van Galen
- Center for Benign Haematology, Thrombosis and Haemostasis, van Creveldkliniek, Utrecht, the Netherlands
| | - Lize F D van Vulpen
- Center for Benign Haematology, Thrombosis and Haemostasis, van Creveldkliniek, Utrecht, the Netherlands
| | - Kathelijn Fischer
- Center for Benign Haematology, Thrombosis and Haemostasis, van Creveldkliniek, Utrecht, the Netherlands
| | - Roger E G Schutgens
- Center for Benign Haematology, Thrombosis and Haemostasis, van Creveldkliniek, Utrecht, the Netherlands
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Casini A, Gebhart J. How to investigate mild to moderate bleeding disorders and bleeding disorder of unknown cause. Int J Lab Hematol 2024; 46 Suppl 1:27-33. [PMID: 38454298 DOI: 10.1111/ijlh.14266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 02/28/2024] [Indexed: 03/09/2024]
Abstract
A bleeding tendency is one of the most common complaints observed by hematologists. It is challenging to differentiate a clinically insignificant bleeding from a bleeding phenotype that requires hemostatic evaluation and medical intervention. A thorough review of personal and familial history, objective assessment of bleeding severity using a bleeding assessment tool, and a focused physical examination are critical to correctly identifying suspected patients with mild to moderate bleeding disorders (MBDs). A basic laboratory work-up should be performed in all patients referred for a bleeding tendency. If a hemostatic abnormality is found such as evidence of von Willebrand disease, a platelet function disorder, or a coagulation factor deficiency, more extensive testing should be performed to further characterize the bleeding disorder. Conversely, if all results are normal the patient is considered to have bleeding disorder of unknown cause (BDUC). For patients with BDUC, further evaluation may include non-routine testing to look for rare bleeding disorders not detected by routine hemostasis tests, such as thrombomodulin-associated coagulopathy, tissue factor pathway inhibitor-related bleeding disorder, hyperfibrinolytic-bleeding disorders or impaired tissue factor production. In this review, we summarize the stepwise diagnostic procedure in MBDs and provide some insights into the biological features of BDUC.
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Affiliation(s)
- Alessandro Casini
- Division of Angiology and Hemostasis, University Hospitals of Geneva, Geneva, Switzerland
| | - Johanna Gebhart
- Department of Medicine I, Division of Hematology and Hemostaseology, Medical University Vienna, Austria
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Berkowitz C, Kirkland K, Ma A, Key NS. Bleeding disorder of unknown cause & unclassified bleeding disorders at US hemophilia treatment centers. Res Pract Thromb Haemost 2024; 8:102296. [PMID: 38292351 PMCID: PMC10824970 DOI: 10.1016/j.rpth.2023.102296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 11/01/2023] [Accepted: 11/20/2023] [Indexed: 02/01/2024] Open
Affiliation(s)
- Callie Berkowitz
- Division of Hematology and Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Kristi Kirkland
- Division of Hematology and Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Alice Ma
- Division of Hematology and Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Nigel S. Key
- Division of Hematology and Blood Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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Mehic D, Kraemmer D, Tolios A, Bücheler J, Quehenberger P, Haslacher H, Ay C, Pabinger I, Gebhart J. The necessity of repeat testing for von Willebrand disease in adult patients with mild to moderate bleeding disorders. J Thromb Haemost 2024; 22:101-111. [PMID: 37741511 DOI: 10.1016/j.jtha.2023.09.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 08/23/2023] [Accepted: 09/13/2023] [Indexed: 09/25/2023]
Abstract
BACKGROUND In patients with mild-to-moderate bleeding disorders (MBD), von Willebrand disease (VWD) is diagnosed at von Willebrand factor (VWF) levels ≤50 IU/dL. Although VWF levels are unstable, repeated testing for VWD diagnosis is not necessarily advised in recent guidelines. OBJECTIVES To analyze the relevance of repeated VWF testing to diagnose VWD in patients with MBD. METHODS Data of 277 patients with MBD from the Vienna Bleeding Biobank with at least 2 separate assessments of VWF antigen (VWF:Ag) and activity (VWF:Act) were analyzed. RESULTS In repeated VWF measurements, 36 patients (13.0%) had "changing" VWF levels (≤/>50 IU/dL), 27 (9.7%) had persistent levels ≤50 IU/dL ("pathologic"), and 214 (77.3%) had levels >50 IU/dL ("normal"). Of the 36 changing patients, 22 (61%) were diagnosed with VWD at baseline, whereas the others only met VWD diagnostic criteria at repeated measurements. Using logistic regression, we estimated a probability of change of 26.4% (95% CI, 12.5-47.4) at baseline VWF levels of 30 IU/dL, 50.8% (95% CI, 35.6-65.8) at 50 IU/dL, 18.8% (95% CI, 12.3-27.6) at 60 IU/dL, and 1.2% (95% CI, 0.3-4.9) at 80 IU/dL. Baseline VWF was a strong predictor for changing status (Χ2 = 49.9; P < .001), while age, sex, Vicenza score, and blood type O had limited added value (Χ2 = 5.1; P = .278). Baseline VWF:Ag or VWF:Act cutoffs of 80 IU/dL had negative predictive values of 98.1% and 99.1% for changing status, respectively. CONCLUSION Our data emphasize an overlap between patients with VWD and MBD with bleeding disorder of unknown cause and underline the need for repeated VWF testing, especially in patients with VWF levels <80 IU/dL.
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Affiliation(s)
- Dino Mehic
- Clinical Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria; Institute of Vascular Biology and Thrombosis Research, Centre of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria. https://twitter.com/dino_mehic
| | - Daniel Kraemmer
- Clinical Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria
| | - Alexander Tolios
- Department of Transfusion Medicine and Cell Therapy, Medical University of Vienna, Vienna, Austria
| | - Julia Bücheler
- Clinical Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria
| | - Peter Quehenberger
- Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
| | - Helmuth Haslacher
- Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
| | - Cihan Ay
- Clinical Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria. https://twitter.com/Cihan_Ay_MD
| | - Ingrid Pabinger
- Clinical Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria. https://twitter.com/IngridPabinger
| | - Johanna Gebhart
- Clinical Division of Hematology and Hemostaseology, Department of Medicine I, Medical University of Vienna, Vienna, Austria.
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Puetz J, Hu B. Factor activity levels and bleeding scores in pediatric hemophilia carriers enrolled in the ATHNdataset. Pediatr Blood Cancer 2023; 70:e30644. [PMID: 37638815 DOI: 10.1002/pbc.30644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/22/2023] [Accepted: 08/14/2023] [Indexed: 08/29/2023]
Abstract
BACKGROUND Multiple studies have now shown that a significant proportion of hemophilia carriers meet the criteria for having hemophilia and/or report abnormal bleeding. However, to date, investigations of hemophilia carriers have almost exclusively involved women over 18 years of age. Little is known about factor activity levels and bleeding scores in carriers during childhood. We queried a large deidentified database of subjects with bleeding disorders residing in the United States to determine factor activity levels and bleeding scores. PROCEDURES The ATHNdataset was queried for hemophilia carriers under 18 years of age. Collected information included demographics, factor activity levels, and bleeding scores. RESULTS Over 700 carriers in the pediatric age group were identified, of which 626 submitted factor activity levels. Nearly half had factor activity levels less than 40 IU/dL, thereby meeting criteria for having hemophilia. Of those reporting bleeding scores, only 13.5% reported an abnormal bleeding score for age. The proportion reporting abnormal bleeding scores was higher in those with factor levels less than 40 IU/dL (23%) than those greater than 40 IU/dL (9.7%). CONCLUSIONS The proportion of pediatric carriers with hemophilia was double of that previously reported for adults. Of those with hemophilia reporting a bleeding score, the majority (77%) did not report an abnormal bleeding score for age. However, nearly 10% of pediatric carriers not meeting criteria for having hemophilia reported abnormal bleeding scores for age. Similar results are reported in adults suggesting that factor activity levels may not be predictive of bleeding symptoms in carriers.
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Affiliation(s)
- John Puetz
- Saint Louis University School of Medicine, SSM Health Cardinal Glennon Children's Hospital, St. Louis, Missouri, USA
| | - Brian Hu
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, American Thrombosis and Hemostasis Network, Rochester, New York, USA
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Eising HP, Punt MC, Schermer T, Leemans JC, Bongers MY. The ISTH-BAT score and outcomes after endometrial ablation in women with heavy menstrual bleeding. Haemophilia 2023; 29:1573-1579. [PMID: 37758646 DOI: 10.1111/hae.14872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 09/11/2023] [Accepted: 09/12/2023] [Indexed: 09/29/2023]
Abstract
BACKGROUND The International Society on Thrombosis and Haemostasis bleeding assessment tool (ISTH-BAT), is used during the diagnostic workup of bleeding disorders. Data on ISTH-BAT scores in women with heavy menstrual bleeding (HMB) undergoing endometrial ablation (EA) could be essential in optimizing HMB counselling. OBJECTIVE To investigate the postsurgical incidence of amenorrhea, dysmenorrhea, quality of life, re-intervention after EA, and ISTH-BAT score. METHODS This study included women who have undergone EA because of HMB. During a follow-up of 2 to 5 years, ISTH-BAT, pictorial blood assessment chart (PBAC), and Short Form-36 survey (SF-36) were administered. At 10 years of follow-up surgical re-interventions were evaluated. RESULTS Seventy-one women were included of whom 77% (n = 55) had an ISTH-BAT score < 6, versus 23% (n = 16) ISTH-BAT score ≥6 (mean age 46.3 versus 42.3, p = 0.004). In the ISTH-BAT ≥6 group versus < 6 group, amenorrhea occurred in 63% (10/16) versus 82% (45/55) (p = 0.111), dysmenorrhea in 38% (6/16) versus 18% (10/55) (p = 0.111), and surgical re-intervention in 19% (3/16) versus 25% (14/55) (p = 0.582). SF-36 item (Bodily) pain was lower in the ISTH-BAT ≥6 group versus < 6 (median score 58.7 vs. 80.0, p = 0.104). CONCLUSIONS An ISTH-BAT score ≥6 may be related to a lower amenorrhea incidence and higher dysmenorrhea rate after EA.
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Affiliation(s)
- Heleen P Eising
- Department of Gynaecology and Obstetrics, Gelre Hospital, Apeldoorn, The Netherlands
- Grow Research School Oncology and Reproduction, Maastricht University, Maastricht, The Netherlands
| | - Marieke C Punt
- Department of Gynaecology and Obstetrics, Gelre Hospital, Apeldoorn, The Netherlands
| | - Tjard Schermer
- Gelre Leerhuis, Department of Epidemiology, Gelre Hospitals, Apeldoorn, The Netherlands
| | - Jaklien C Leemans
- Department of Gynaecology and Obstetrics, Máxima Medical Center, Veldhoven, The Netherlands
| | - Marlies Y Bongers
- Grow Research School Oncology and Reproduction, Maastricht University, Maastricht, The Netherlands
- Department of Gynaecology and Obstetrics, Máxima Medical Center, Veldhoven, The Netherlands
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Whyte CS, Morrow GB, Gauer JS, Montague SJ, Nicolson PLR. Novel therapeutics and emerging technology in haemostasis and thrombosis: highlights from the British society for haemostasis and thrombosis annual meeting. Front Cardiovasc Med 2023; 10:1225243. [PMID: 37745127 PMCID: PMC10512947 DOI: 10.3389/fcvm.2023.1225243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 08/17/2023] [Indexed: 09/26/2023] Open
Abstract
The 2023 annual meeting of the British Society for Haemostasis and Thrombosis (BSHT) was held in Birmingham, United Kingdom. The theme of this year's meeting was novel therapeutics and emerging technology. Here, the exciting research presented at the meeting is discussed.
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Affiliation(s)
- Claire S. Whyte
- Aberdeen Cardiovascular and Diabetes Centre, School of Medicine, Medical Sciences and Nutrition, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Gael B. Morrow
- Aberdeen Cardiovascular and Diabetes Centre, School of Medicine, Medical Sciences and Nutrition, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
- Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Julia S. Gauer
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom
| | - Samantha J. Montague
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Philip L. R. Nicolson
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
- West Midlands Haemophilia Comprehensive Care Centre, University Hospitals Birmingham Foundation Trust, Birmingham, United Kingdom
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