Table 3.

Laboratory Pattern in Von Willebrand Disease

Laboratory Assay	Type 1	Type 2A	Type 2B	Type 2M	Type 2N	Type 3
APTT	Prolonged or normal	Prolonged or normal	Normal or prolonged	Normal or prolonged	Prolonged or normal	Prolonged
Platelet count	Normal	Normal	Low or normal	Normal	Normal	Normal
PFA-100 (closure time; CT)	Prolonged or normal	Prolonged, no closure	Prolonged, no closure	Prolonged, no closure	Normal	Prolonged, no closure
FVIII:C	Low or normal	Low or normal	Low or normal	Normal or low	Low	Low (<10 U/dL)
VWF:Ag	Low (<50 U/dL)	Low or normal	Low or normal	Normal or low	Normal or low	Very low (<3 U/dL)
VWF:RCo VWF:GPIbR VWF:GPIbM	Low,rarely normal	Low (<30 U/dL)	Low,rarely normal	Low or normal	Normal or low	Very low (<3 IU/dL)
VWF:CB	Low,rarely normal	Very low (<15 U/dL)	Low (<40 U/dL)	Low or normal	Normal or low	Very low (<3 U/dL)
VWF:RCo/VWF:Ag ratio	Normal (>0.7)	Low (<0.7)	Low (<0.7)	Low or normal	Normal (>0.7)	Variable
RIPA using patient platelets	Reduced or normal	Reduced or normal	Increased	Reduced or normal	Normal	Absent
VWF multimer pattern	Normal pattern, VWF reduced	Large to intermediate multimers lacking	Large multimers missing	Normal VWF multimer distribution (but with possible abnormal bands)	Normal	Multimers absent
VWFpp/VWF:Ag ratio	Normal, Increased in type 1C	Normal or increased	Increased	Normal	Normal	Absent

Abbreviations: APTT, activated partial thromboplastin time; FVIII:C, factor VIII coagulant; VWF:Ag, VWF antigen; VWF:RCo, VWFristocetin cofactor; VWF:GPIbR, VWF recombinant GPIbα fragments; VWF:GPIbM, VWF recombinant GPIbα fragments with two mutations; VWF:CB, VWF collagen binding; RIPA, ristocetin-induced platelet agglutination; VWFpp, VWF propeptide.