UCSF Navigation Bar

UCSF Departments of Pathology & Laboratory Medicine Home Page

Lab Manual for UCSF Clinical Laboratories

Lab Manual for SFGH

Internal Resources

Clinical Question: Does my patient have von Willebrand disease? If so, which type?

Item Value
ID 9
Question Does my patient have von Willebrand disease? If so, which type?
AlgorithmLink Click here for algorithm
AlgorithmDescription vWD
- asymptomatic abnormalities of vWF are present in up to ~1% of people
- prevalence of symptomatic vWD is ~1 in 8000 (between 1 in 3000-10000)
- primary symptom of vWD is mucocutaneous bleeding

vWD classification:
- type 1 = partial quantitative defect in vWF
- type 2 = qualitative defect in vWF
- type 3 = complete quantitative defect in vWF

notes:
- vWF may be elevated in many situations (neonatal period, pregnancy, inflammatory states, post-surgery, among others), which could potentially mask mild type 1 disease; in such settings, repeat testing to exclude vWD may be appropriate
- if initial vWD testing is abnormal, strongly consider repeat testing for confirmation and/or Hematology referral"

Please call the hematology laboratory medicine resident at 353-1614 with any questions about this algorithm.
ICD10 D68.0,D68.9,D69.6,D69.9,R23.3
PubMedID PMID:16634745,11686101,17596142,18805962,20231421,17786534,17408405,16961623,18983516,22431572,19506352,19687512,18315614,16246252,16634760,19214910,16862528,20590859
NLMID:101518625,101539022,101595235

 

Tests associated with this clinical question:

Click on the test name for more information about the use of this test to answer this clinical question

ID Test Code Test Name Comment
45 PTT Complete Blood Count (includes Platelet Count) - prolongation is neither sensitive nor specific for vWD, although prolongation may be a feature of vWD (in particular, severe type 1 as well as types 2N and 3)
- consider other diagnoses in addition to vWD if prolonged
46 CBC Factor 8 Activity - thrombocytopenia is neither sensitive nor specific for vWD, although thrombocytopenia may be a feature of vWD (in particular, type 2B and platelet-type)
- consider other diagnoses in addition to vWD if thrombocytopenic
47 BT Miscellaneous Outside Laboratory Test - global test of primary hemostasis
- high analytic variability, insufficiently sensitive/specific for vWD
- not recommended for vWD screening
48 PFA100 Prothrombin Time - insufficiently sensitive/specific for vWD (particularly for mild disease)
- not recommended for vWD screening
49 VWFAG Activated Partial Thromboplastin Time - measurement of amount of vWF protein in patient plasma
- normal in roughly 20% of people with vWD (particularly in type 2B disease)
- ideally, ordered as part of von Willebrand panel (VWP, 1006)

* sensitivity/specificity depend on cutoff (above values are for 2.5th percentile, roughly 50 IU/dL)
50 RCOF Ristocetin Aggregation - measurement of vWF function in patient plasma
- exon 28 SNPs identified in African-American population may decrease ristocetin cofactor activity but do not contribute to clinical bleeding
- ideally, ordered as part of von Willebrand panel (VWP, 1006)

* sensitivity/specificity depend on cutoff (above values are for 2.5th percentile, roughly 50 IU/dL)
70 F8 Ristocetin Cofactor Activity - vWF binds to F8 and protects it from degradation in plasma
- F8 activity is decreased in many types of vWD and is complementary to vWF antigen levels
- ideally, ordered as part of von Willebrand panel (VWP, 1006)
71 VWMULT von Willebrand Factor Antigen - vWF circulates in plasma as a series of multimers of variable size
- multimer analysis detects changes in the size distribution of plasma multimers (a qualitative abnormality)
73 VW2NR von Willebrand Factor - Factor 8 Binding Ratio - decreased vWF-F8 binding ratio suggests defective interaction between vWF and F8
- useful in distinguishing hemophilia A (including carrier states) from vWD type 2N
74 MOLT Misc. Outside Laboratory Test vWF-collagen binding assay, sent to Quest
- detects rare 2M variants with defective vWF-collagen binding (not detected by any other assays)
- does not replace RCOF (vWF-collagen binding assay is insensitive to other 2M mutations)
75 MOLT Misc. Outside Laboratory Test VWF exon 28 gene analysis, sent to Blood Center of Wisconsin
"- in combination with GP1BA sequencing, VWF exon 28 gene analysis accurately distinguishes vWD type 2B from platelet-type vWD
- exon 28 sequencing may also be useful in challenging cases of type 2 disease (detects most 2B and 2M mutations)"
76 MOLT Misc. Outside Laboratory Test GP1BA gene analysis
- in combination with VWF exon 28 sequencing, GP1BA gene analysis accurately distinguishes vWD type 2B from platelet-type vWD
- exon 28 sequencing may also be useful in challenging cases of type 2 disease (detects most 2B and 2M mutations)

 

Clinical Algorithm:

It appears that you do not have a PDF plugin for this browser. You can Click Here to download the PDF file.

It appears that you do not have a PDF plugin for this browser. You can Click Here to download the PDF file.

It appears that you do not have a PDF plugin for this browser. You can Click Here to download the PDF file.

It appears that you do not have a PDF plugin for this browser. You can Click Here to download the PDF file.

UCSF home page UCSF home page About UCSF Search UCSF UCSF Medical Center