Significant differences between low VWF and type 1 VWD
| . | Low VWF . | Type 1 VWD . |
|---|---|---|
| VWD type | Partial quantitative | Partial quantitative |
| Plasma VWF levels, IU/dL | 30-50* | <30 |
| Bleeding phenotype | Variable bleeding. Independent of plasma VWF levels. Significant HMB & PPH in some patients | Mucosal bleeding. Correlates inversely with residual plasma VWF levels. |
| Sex | Marked female predominance | Less female bias |
| ABO blood group | Group O+++ | Group O+ |
| VWF sequence variants | ∼40% patients. Pathological importance for many variants unclear. | Present in >80% cases |
| Pathophysiology | Multifactorial. Predominantly reduced biosynthesis. Subtle increased clearance in ∼25% patients (VWFpp/VWF:Ag ∼ 2). | Dependent upon VWF mutation. Reduced biosynthesis. Enhanced clearance in ∼45% cases. Type 1C VWD (VWFpp/VWF:Ag >3). |
| VWF glycosylation abnormalities | Enhanced SNA binding, increased RCA-I binding, and reduced sialylation | Increased RCA-I binding, PNA binding, and T antigen expression and reduced sialylation |
| Platelet VWF levels | May be reduced or normal | May be reduced or normal |
| Abnormal angiogenesis | Unknown | Previously reported |
| . | Low VWF . | Type 1 VWD . |
|---|---|---|
| VWD type | Partial quantitative | Partial quantitative |
| Plasma VWF levels, IU/dL | 30-50* | <30 |
| Bleeding phenotype | Variable bleeding. Independent of plasma VWF levels. Significant HMB & PPH in some patients | Mucosal bleeding. Correlates inversely with residual plasma VWF levels. |
| Sex | Marked female predominance | Less female bias |
| ABO blood group | Group O+++ | Group O+ |
| VWF sequence variants | ∼40% patients. Pathological importance for many variants unclear. | Present in >80% cases |
| Pathophysiology | Multifactorial. Predominantly reduced biosynthesis. Subtle increased clearance in ∼25% patients (VWFpp/VWF:Ag ∼ 2). | Dependent upon VWF mutation. Reduced biosynthesis. Enhanced clearance in ∼45% cases. Type 1C VWD (VWFpp/VWF:Ag >3). |
| VWF glycosylation abnormalities | Enhanced SNA binding, increased RCA-I binding, and reduced sialylation | Increased RCA-I binding, PNA binding, and T antigen expression and reduced sialylation |
| Platelet VWF levels | May be reduced or normal | May be reduced or normal |
| Abnormal angiogenesis | Unknown | Previously reported |
+, mild increase in prevalence; +++, markedly more prevalent; PNA, peanut agglutinin; RCA-I, Ricinus communis agglutinin I; SNA, Sambucus nigra agglutinin; VWFpp, VWF propeptide.
There are some differences between International Consensus guidelines for the optimal range.