Diagnosis of Type 2 and 3 von Willebrand Disease

Typical laboratory findings in type 2 vWD

TypevWF risto­cetin co­factor activity (IU/dL)vWF anti­gen (IU/dL)RCo/Ag ratioOther features
1: partial quan­titative deficiency< 30< 30≥ 0.7FVIII normal or low
RIPA normal
LD-RIPA absent
Multimers normal
2A: de­ficiency of high MW multi­mers< 3030 - 200< 0.7FVIII normal or low
RIPA reduced
LD-RIPA absent
Reduced high MW multimers
2B: in­creased affinity for platelet GP1b< 3030 - 200< 0.7FVIII normal or low
RIPA normal
LD-RIPA increased
Reduced high MW multimers
vWF platelet binding increased (using patient plasma and control platelets)
Thrombo­cyto­penia
2M: re­duced platelet agg­rega­tion but normal multi­mers< 3030 - 200< 0.7FVIII normal or low
RIPA reduced
LD-RIPA absent
Multimers normal
2N: reduced FVIII binding30 - 20030 - 200≥ 0.7FVIII very low
RIPA normal
LD-RIPA absent
Multimer analysis normal
3: near-complete de­ficiency< 3< 3n/aFVIII very low
RIPA absent
LD-RIPA absent
Multimer analysis not possible
Platelet type: gain of function mu­tation of platelet GP1bLowVery low< 0.7FVIII normal or low
RIPA normal
LD-RIPA increased
High MW multimers reduced
vWF platelet binding normal (using patient plasma and control platelets)
Thrombo­cyto­penia

Typical laboratory findings in types 1, 2 and 3 von Willebrand disease (vWD) were summarised in vWD guidelines published by the the National Heart, Lung, and Blood Institute (NHLBI) in 2008.1 Note that the NHLBI guidelines suggest use a range of < 0.5 - 0.7 as the vWF:RCO/vWF:Ag ratio cut-off for the consideration of type 2 vWD. The cut-off of <0.7 shown on this table is that proposed in the 2004 UK Haemophilia Doctors' Organisation guidelines.2