General characterization and laboratory results of patients with VWD type 2 in the Milan cohort
| VWD type . | N of patients . | FVIII:C, IU/dL−1 . | VWF:Ag, IU/dL−1 . | VWF activity, IU/dL−1 . | VWF activity/VWF:Ag ratio . | VWF:CB, IU/dL−1* . | VWF:CB/VWF:Ag ratio . |
|---|---|---|---|---|---|---|---|
| All 2A | 98 | 47 (20-196) | 33 (7-370) | 11 (5-88) | 0.37 (0.06-1) | 7 (1-59) | 0.2 (0.02-0.9) |
| 2A(IIA) | 64 | 52 (20-100) | 45 (7-130) | 10 (4-29) | 0.28 (0.06-0.68) | 6 (1-26) | 0.15 (0.02-0.7) |
| 2A(IIE) | 32 | 40 (24-96) | 20 (13-149) | 13 (6-60) | 0.52 (0.23-1) | 10 (4-41) | 0.41 (0.2-0.9) |
| 2A(IIC) | 1 | 56 | 18 | 8 | 0.44 | 3 | 0.17 |
| 2A(IIH) | 1 | 196 | 370 | 88 | 0.23 | 59 | 0.16 |
| All 2B | 85 | 62 (6-132) | 55 (18-170) | 25 (4-99) | 0.46 (0.1-1) | 21 (2-82) | 0.4 (0.06-1.4) |
| Classical 2B | 64 | 61 (6-132) | 52 (18-170) | 22 (4-99) | 0.35 (0.1-0.93) | 15 (2-62) | 0.2 (0.06-1) |
| 2B NY | 21 | 70 (40-105) | 57 (21-80) | 39 (10-73) | 0.7 (0.4-1) | 45 (7-82) | 0.87 (0.33-1.4) |
| All 2M† | 112 | 50 (23-133) | 28 (12-147) | 11 (5-101) | 0.47 (0.11-1.1) | 15 (3-80) | 0.58 (0.1-1.6) |
| Classical 2M | 46 | 48 (23-124) | 26 (12-130) | 11 (5-44) | 0.42 (0.14-1) | 17 (8-80) | 0.7 (0.3-1.3) |
| 2M/2A | 37 | 48 (24-133) | 29 (12-90) | 9 (5-23) | 0.29 (0.15-0.68) | 14 (3-52) | 0.5 (0.1-0.95) |
| 2MCB | 29 | 51 (35-133) | 30 (18-147) | 25 (11-101) | 0.8 (0.5-1) | 14 (7-66) | 0.5 (0.14-1) |
| All 2N‡ | 26 | 45 (13-102) | 69 (22-156) | 60 (18-144) | 0.85 (0.68-1.3) | 53 (12-134) | 0.87 (0.5-1.4) |
| 2N | 16 | 37 (13-50) | 60 (22-156) | 41 (18-106) | 0.8 (0.63-1.40) | 39 (12-61) | 0.88 (0.5-1.4) |
| Carrier 2N | 10 | 71 (50-102) | 98 (56-121) | 88 (47-144) | 0.89 (0.64-1.1) | 72 (59-88) | 0.97 (0.72-1.2) |
| VWD type . | N of patients . | FVIII:C, IU/dL−1 . | VWF:Ag, IU/dL−1 . | VWF activity, IU/dL−1 . | VWF activity/VWF:Ag ratio . | VWF:CB, IU/dL−1* . | VWF:CB/VWF:Ag ratio . |
|---|---|---|---|---|---|---|---|
| All 2A | 98 | 47 (20-196) | 33 (7-370) | 11 (5-88) | 0.37 (0.06-1) | 7 (1-59) | 0.2 (0.02-0.9) |
| 2A(IIA) | 64 | 52 (20-100) | 45 (7-130) | 10 (4-29) | 0.28 (0.06-0.68) | 6 (1-26) | 0.15 (0.02-0.7) |
| 2A(IIE) | 32 | 40 (24-96) | 20 (13-149) | 13 (6-60) | 0.52 (0.23-1) | 10 (4-41) | 0.41 (0.2-0.9) |
| 2A(IIC) | 1 | 56 | 18 | 8 | 0.44 | 3 | 0.17 |
| 2A(IIH) | 1 | 196 | 370 | 88 | 0.23 | 59 | 0.16 |
| All 2B | 85 | 62 (6-132) | 55 (18-170) | 25 (4-99) | 0.46 (0.1-1) | 21 (2-82) | 0.4 (0.06-1.4) |
| Classical 2B | 64 | 61 (6-132) | 52 (18-170) | 22 (4-99) | 0.35 (0.1-0.93) | 15 (2-62) | 0.2 (0.06-1) |
| 2B NY | 21 | 70 (40-105) | 57 (21-80) | 39 (10-73) | 0.7 (0.4-1) | 45 (7-82) | 0.87 (0.33-1.4) |
| All 2M† | 112 | 50 (23-133) | 28 (12-147) | 11 (5-101) | 0.47 (0.11-1.1) | 15 (3-80) | 0.58 (0.1-1.6) |
| Classical 2M | 46 | 48 (23-124) | 26 (12-130) | 11 (5-44) | 0.42 (0.14-1) | 17 (8-80) | 0.7 (0.3-1.3) |
| 2M/2A | 37 | 48 (24-133) | 29 (12-90) | 9 (5-23) | 0.29 (0.15-0.68) | 14 (3-52) | 0.5 (0.1-0.95) |
| 2MCB | 29 | 51 (35-133) | 30 (18-147) | 25 (11-101) | 0.8 (0.5-1) | 14 (7-66) | 0.5 (0.14-1) |
| All 2N‡ | 26 | 45 (13-102) | 69 (22-156) | 60 (18-144) | 0.85 (0.68-1.3) | 53 (12-134) | 0.87 (0.5-1.4) |
| 2N | 16 | 37 (13-50) | 60 (22-156) | 41 (18-106) | 0.8 (0.63-1.40) | 39 (12-61) | 0.88 (0.5-1.4) |
| Carrier 2N | 10 | 71 (50-102) | 98 (56-121) | 88 (47-144) | 0.89 (0.64-1.1) | 72 (59-88) | 0.97 (0.72-1.2) |
Data are presented as median (range).
Missing number for VWF:CB in type 2A (n = 11), 2B (n = 5), 2M (n = 7), and 2N (n = 11).
Type 2M could be due to distinct etiologies, either a defective binding of VWF to platelet GPIb (classical 2M) or collagen (2MCB). Patients with classical 2M had a reduced VWF activity/VWF:Ag ratio with a normal median VWF:CB/VWF:Ag ratio, whereas in 2MCB, the opposite is actually the case. For this reason, the VWF:CB/VWF:Ag ratio of 2M, which represents all three subgroup, is 0.58, whereas classical 2M has a ratio of 0.7.
Type 2N includes patients who showed a markedly (2N) or slightly (carrier 2N) reduced VWF:FVIIIB result.