Abstract Number: PB0937
Meeting: ISTH 2021 Congress
Theme: Platelet Disorders, von Willebrand Disease and Thrombotic Microangiopathies » VWF and von Willebrand Factor Disorders - Clinical Conditions
Background: The diagnosis of von Willebrand Disease (VWD) is an intricate process. The basic diagnostic panel includes von Willebrand factor antigen assay (VWF:Ag), VWF ristocetin cofactor activity (VWF:RCo), and Factor VIII:C.
Aims: To analyze the spectrum and coagulation profile of VWD cases diagnosed based on a simplified algorithm (Figure 1).
Methods: This was a cross-sectional study over five and half years. Cases with normal screening coagulogram, or isolated activated partial thromboplastin time prolongation, or with prolonged bleeding time where platelet function defect was excluded, VWF:Ag assay by either ELISA [Raybiotech Life, Georgia, United States] or automated coagulometer [STA compact CT, Diagnostica Stago, Asnières-sur-Seine, France], VWF: RCo [490-2D, Chronolog Corporation, Havertown, PA, USA] and FactorVIII:C [automated] were done. Ratios of function to antigen parameters which included VWF:RCo/VWF:Ag and FVIII:C /VWF:Ag were derived. Multimer assay [Hydragel 5 von Willebrand Multimers kits, Sebia, Lisses, France] was done in a few cases.
Results: Forty-two patients had some form of VWD/ defect of VWF as follows: Type 3 in 13, Type 2N in 7, Type 2N/3 (incomplete work-up) in 2, Type 2 (not further categorized) in 9, Low VWF in 10, and one patient of Waldenstrom Macroglobulinemia with acquired VWD. The mean age of presentation was either in the second or third decade with a female predominance with common bleeding patterns of epistaxis, bleeding gums, easy bruising, and menorrhagia. The hemostasis parameters of the various categories are summarized in Table 1.
Parameters/ Diagnosis (n) | VWD Type 3 (13) | VWD Type 2N (7) | VWD Type2 (9) | Low VWF (10) |
Age in years, Mean (SD) | 29.4 (15.9) | 18.8 (12.4) | 12.7 (7.7) | 15.7(10.3) |
Gender, Male%: Female% | 30.8:69.2 | 28.6: 71.4 | 44.4: 55.6 | 30:70 |
BT in min, Median (Range) | >15(2->15) | 4:30 (3-10:30) | 3:45(1:30->15) | 3(1:30-5) |
aPTT in sec, Mean (SD) | 58.1 (13.7) | 53.5(4.7) | 40.1(6.8) | 30.9 (2.5) |
FVIII level in %, Median (Range) | 5.6 (1-24) | 4(1-17) | 35 (31-44) | Not available (NA) |
VWF:RCo in %, Median (Range) | 0 (0-4) | 72 (56.2 -128) | 13(0-45) | 31 (NA) |
VWF:Ag in % or ng/ml , Median (Range) | 1(0-3) | 118.1(50-183) | 56 (18-95) | 47 (37-49.6) |
Ristocetin aggregation %, Median (Range) | 7.5 (0-16) | 42(19-85) | 26 (3-95) | 55(17-79) |
Multimer assay (Total done/Pattern) | 7, Absent in all | 2, Normal pattern | 2, Lack of HMWM (type 2A) | NA |
Conclusions: The combination of VWF: Ag assay, VWF:RiCo, and FactorVIII:C forms the tripod for diagnosis and classification of major VWD types. Further subtyping can be done by multimer analysis. A greater proportion of severe types of VWD were observed in our study. However, this would not be representative of the population prevalence of various types since patients with more severe bleeding phenotypes are likely to have a hospital referral.
To cite this abstract in AMA style:
Kar R, Balakrishnan K, Logaiyappan A, Jayachandan J, Basu D. Diagnosis of von Willebrand Disease-intricacies and Challenges: An Experience from a Tertiary Care Centre in Southern India [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/diagnosis-of-von-willebrand-disease-intricacies-and-challenges-an-experience-from-a-tertiary-care-centre-in-southern-india/. Accessed March 22, 2024.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/diagnosis-of-von-willebrand-disease-intricacies-and-challenges-an-experience-from-a-tertiary-care-centre-in-southern-india/