PB0278 - Current practice regarding Bleeding Disorder of Unknown Cause (BDUC) in the Netherlands: a national survey

Sunday, June 23, 2024

13:45 – 14:45 ICT

Room: Exhibition Hall

Presenting Author(s)

Caroline Mussert, MD

PhD candidate
Department of hematology – pediatric hematology, Erasmus Medical Center Sophia Children's Hospital, University Medical Center Rotterdam, Rotterdam, the Netherlands
Rotterdam, Zuid-Holland, Netherlands

Co-Author(s)

Amaury Monard

PhD candidate
Internal Medicine, Maastricht University Medical Center +, Maastricht, the Netherlands
Maastricht, Limburg, Netherlands
MK

Marieke J.H.A. Kruip

Hematologist
Department of Hematology, Erasmus MC, Erasmus University Medical Centre Rotterdam, Rotterdam, the Netherlands
Rotterdam, Zuid-Holland, Netherlands
Yvonne Henskens

Professor of the department of clinical chemistry
MUMC+
maastricht, Limburg, Netherlands
Mv

Maartje van den biggelaar

Principal investigator
Molecular Hematology, Sanquin Research, Amsterdam, The Netherlands
Amsterdam, Noord-Holland, Netherlands
T. T. van Duijl, T.T.

Post-doctoral researcher
Molecular Hematology, Sanquin Research, Asterdam, The Netherlands
Amsterdam, Noord-Holland, Netherlands
Roger E.G. Schutgens

Internist-hematologist
Department of Benign Hematology, van Creveldkliniek, University Medical Center Utrecht and University Utrecht, Utrecht, the Netherlands
Utrecht, Utrecht, Netherlands
SS

Saskia E.M. Schols

Internist-hematologist
Department of Hematology, Radboud university medical center, Nijmegen, The Netherlands
Nijmegen, Gelderland, Netherlands
KF

Karin Fijnvandraat

Professor
Emma Kinderziekenhuis/AMC, University of Amsterdam, Netherlands
Amsterdam, Noord-Holland, Netherlands
Karina Meijer

MD, PhD, professor
Department of Hematology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
Groningen, Groningen, Netherlands
Pd

Paul L. den Exter

Hematologist
Department of Thrombosis and Hemostasis, Leiden University Medical Center, Leiden, the Netherlands
Leiden, Zuid-Holland, Netherlands
LN

Laurens Nieuwenhuizen

MD
Department of Hematology, Maxima Medisch Centrum, Eindhoven, The Netherlands
Eindhoven, Noord-Brabant, Netherlands
Iris van Moort

Postdoctoral researcher
Erasmus MC University Medical Center, Rotterdam, The Netherlands
Rotterdam, Zuid-Holland, Netherlands
MC

Marjon H. Cnossen

MD, PhD, professor
Department of Pediatric Hematology and Oncology, Erasmus MC Sophia Children’s Hospital, University Medical Center Rotterdam, Rotterdam, The Netherlands
Rotterdam, Zuid-Holland, Netherlands
Floor Heubel-Moenen

MD, PhD
Department of Hematology, Maastricht University Medical Center, Maastricht, The Netherlands
Maastricht, Limburg, Netherlands

Background: The majority of individuals with a clinically relevant bleeding tendency are classified as having a ‘bleeding disorder of unknown cause’ (BDUC), if a diagnosis remains absent after extensive laboratory testing. There is wide variation in used BDUC definitions and performed laboratory tests to rule out established bleeding disorders. Clear guidelines for diagnosis, treatment and follow-up are lacking.

Aims: To investigate current practices regarding BDUC in the Netherlands as a foundation for guideline development.

Methods: From June to October 2023, an online survey was sent to 54 hematologists (pediatric and adult), internists vascular medicine, nurse practitioners and clinical chemists, working in Dutch hemophilia-treatment-centers. Questions comprised the essentials of a BDUC definition, observed bleeding phenotype, usual diagnostic process, treatment and follow-up. A cut-off of >70% agreement was defined.

Results: Thirty-nine (72%) recipients completed the survey including 24 hematologists/internists vascular medicine, 8 nurse practitioners and 7 clinical chemists. Nineteen percent of physicians indicates no formal registration of BDUC patients. A BDUC definition should entail the presence of 1) increased bleeding tendency, 2) elevated bleeding assessment tool (BAT) score, 3) exclusion of other (hemostatic) causes and 4) absence of abnormal laboratory test results. To score bleeding symptoms, 88% of physicians applies a BAT, predominantly the ISTH-BAT (93%). Significant heterogeneity is observed in the performed laboratory tests and sequence of execution. In general, a stepwise approach is used to determine the extent and type of laboratory testing. Most frequently prescribed treatments are tranexamic acid and desmopressin. Follow-up depends on bleeding phenotype and history.

Conclusion(s): Based on preliminary results, four elements of a BDUC definition were identified. Furthermore, there is need for agreement on a standard set of performed laboratory tests to diagnose patients with BDUC. National consensus resulting in a national guideline will be achieved through panel expert discussion within the BDUC study group which represents all Dutch hemophilia-treatment-centers.