What is the appropriate diagnostic workup and treatment for von Willebrand disease?

Von Willebrand Disease: Diagnostic Workup and Treatment

Diagnosis

Diagnose VWD when three criteria are met: personal history of excessive mucocutaneous bleeding, family history of bleeding, and reduced VWF levels confirmed by laboratory testing 1.

Initial Diagnostic Approach

Begin with a bleeding assessment tool to quantify bleeding symptoms and identify patients requiring hemostatic testing 1. Look specifically for:

• Easy bruising
• Epistaxis (frequent or prolonged)
• Prolonged bleeding from minor wounds or oral cavity
• Heavy menstrual bleeding
• Gastrointestinal bleeding
• Excessive bleeding after surgery or dental procedures

Laboratory Testing Algorithm

Order an initial 4-test panel 1:

1. VWF antigen (VWF:Ag)
2. VWF activity (platelet-dependent assay: VWF:GPIbM or VWF:GPIbR preferred over ristocetin cofactor)
3. Factor VIII coagulant activity (FVIII:C)
4. VWF collagen binding

Also obtain: CBC (to assess for thrombocytopenia), PT, and PTT 1.

Diagnostic Thresholds

Type 1 VWD:

• VWF:Ag and/or VWF activity <0.30 IU/mL regardless of bleeding symptoms
• OR VWF:Ag and/or VWF activity <0.50 IU/mL with abnormal bleeding 1
• VWF:Ag and activity reduced proportionately (ratio >0.7)

Type 2 VWD:

• Use ratio of VWF activity to VWF:Ag <0.7 (not <0.5) to confirm diagnosis 1
• Type 2A: Loss of high molecular weight multimers, reduced VWF activity disproportionate to antigen
• Type 2B: Use targeted genetic testing over RIPA assay to confirm; often presents with thrombocytopenia 1
• Type 2M: Defective VWF-platelet interaction without loss of high molecular weight multimers
• Type 2N: Normal or slightly reduced VWF levels but FVIII reduced (0.05-0.40 IU/mL); use VWF:FVIIIB assay or targeted genetic testing 1

Type 3 VWD:

• VWF:Ag and activity <0.05 IU/mL
• FVIII:C <0.10 IU/mL 1

Type 1C VWD (increased clearance):

• VWFpp to VWF:Ag ratio >3 indicates this subtype 1

Critical Testing Considerations

Timing matters: Test at physiologic baseline, avoiding:

• Active bleeding or heavy menstrual bleeding
• Stress or recent exercise
• Estrogen therapy or pregnancy
• Delay testing until anemia resolves 1

Important caveat: VWF levels increase 1-2% per year with age and may normalize over time. Do not remove a diagnosis of type 1 VWD based solely on VWF rising with age—instead, reconsider the diagnosis 1.

Repeat testing is often required for accurate diagnosis 1.

---

Treatment

Desmopressin (DDAVP)

Perform a desmopressin trial to determine therapeutic response before relying on it for hemostasis 2, 3.

• First-line for Type 1 VWD (most patients respond)
• Contraindicated in Type 2B VWD (worsens thrombocytopenia)
• Variable response in Type 2A and 2M
• Ineffective in Type 3 VWD

VWF Replacement Therapy

Use VWF-containing concentrates for:

• Type 2 and Type 3 VWD (cornerstone of treatment) 4, 3
• Type 1 VWD patients who fail or cannot use desmopressin
• Major surgery requiring specific VWF/FVIII targets

Target levels for major surgery 2, 3:

• VWF activity and FVIII activity to appropriate hemostatic levels (typically >0.50 IU/mL, often higher depending on procedure)

Adjunctive Therapies

Tranexamic acid (antifibrinolytic):

• Effective for mucosal bleeding, dental procedures, heavy menstrual bleeding
• Can be used alone or combined with other therapies 3

Hormonal therapies:

• Combined oral contraceptives or levonorgestrel IUD for heavy menstrual bleeding management 2, 3

Prophylaxis

Consider prophylaxis for patients with frequent recurrent bleeding to reduce bleeding episodes and improve quality of life 2, 3.

Special Populations

Perioperative management:

• Minor surgery/invasive procedures: Strategies to reduce bleeding include desmopressin (if responsive) or VWF concentrates 2
• Major surgery: Target specific VWF and FVIII levels with replacement therapy

Obstetric management:

• Neuraxial anesthesia: Ensure adequate VWF/FVIII levels
• Postpartum: Continue monitoring and treatment as VWF levels may drop 2

Anticoagulation/antiplatelet therapy:

• Can be used when indicated for cardiovascular disease, but requires careful assessment and often concurrent hemostatic support 2

---

Key Pitfalls to Avoid

1. Do not use ABO-specific reference ranges—they are not clinically useful 1
2. Do not test during active bleeding, stress, or pregnancy—VWF levels will be falsely elevated 1
3. Do not use the old 0.5 ratio cutoff for Type 2 VWD—use 0.7 instead 1
4. Do not give desmopressin to Type 2B patients—it worsens thrombocytopenia
5. Do not dismiss the diagnosis if VWF normalizes with age—reconsider but don't automatically remove the diagnosis 1

The 2021 ASH/ISTH/NHF/WFH guidelines remain current as of 2025, with no new evidence requiring revision 2.