Hemostasis Today

July, 2026
July 2026
M T W T F S S
 12345
6789101112
13141516171819
20212223242526
2728293031  
Muhammet Özbilen: The Hidden Burden of BDUC
Jul 20, 2026, 14:18

Muhammet Özbilen: The Hidden Burden of BDUC

Muhammet Özbilen, Associate Professor Doctor at Ordu University, shared a post on LinkedIn:

“Iron Deficiency Update – Issue N5 is out

‘No diagnosis, but very real patients: Bleeding Disorder of Unknown Cause’

A patient bruises easily, bleeds after surgery, struggles with heavy periods and iron deficiency — yet every lab test is normal.

This isn’t the exception; it’s the rule. In up to two-thirds of adults with a mild-to-moderate bleeding tendency, no specific hemostatic abnormality is found.

They’re diagnosed with a Bleeding Disorder of Unknown Cause (BDUC) — the focus of Mehic et al.’s review in the International Journal of Laboratory Hematology.

Why it matters: These patients face impaired quality of life, real bleeding risk (especially around surgery and childbirth), and frequent iron deficiency.

Notably, up to 80% are women – a reminder of how often heavy menstrual bleeding is overlooked.

BDUC is a diagnosis of exclusion.

CFD, von Willebrand disease (VWD), and platelet function disorders must all be ruled out first.

Critical thresholds:

  • Hemophilia A/B (FVIII/FIX): ISTH cutoff less than 40%, though studies suggest 50% may be clinically more relevant.
  • VWD:
  • VWF less than 50 IU/dL with bleeding – diagnostic;
  • less than 30 IU/dL –  diagnostic regardless of symptoms.
  • Type 2 VWD: VWF:Act/Ag ratio less than 0.7.

Blind spots:

  • A normal aPTT doesn’t exclude mild FVIII, IX, or XI deficiency.
  • Factor XIII deficiency affects neither PT nor aPTT — routine testing will never catch it.
  • The PFA-100/-200 can’t reliably separate PFD from BDUC. LTA remains the gold standard.

One measurement can mislead. VWF levels fluctuate with estrogen, age, and inflammation.

In Vienna Biobank data, nearly a quarter of VWD diagnoses were only established at follow-up — so repeat testing is essential.

Despite no unifying diagnosis, these patients share a real phenotype and real risk.

Management must go beyond labeling – toward individualized care ahead of hemostatic challenges.

Sometimes bleeding has no name on a lab report. But the patient, and the risk, are very real.

What’s your biggest challenge with BDUC patients? ”

Muhammet Özbilen: The Hidden Burden of BDUC

Stay updated with Hemostasis Today.