Type 1 von Willebrand disease — a clinical retrospective study of the diagnosis, the influence of the ABO blood group and the role of the bleeding history

Abstract

Summary. This clinical retrospective study investigated the dif®culties in diagnosing type 1 von Willebrand disease (VWD). A total of 246 patients previously diagnosed with type 1 VWD were reclassi®ed into`possible' type 1 VWD (patients with low levels of VWF adjusted for the blood group and either a signi®cant bleeding history or family history) and`de®nite' type 1 VWD, requiring low levels of von Willebrand factor (VWF), a bleeding history and inheritance. On reclassi®cation, only 144/246 (59%) patients had low VWF levels adjusted for blood group, 88/246 (36%) patients met all the criteria for`de®nite' type 1 VWD and 51/246 (21%) patients were`possible' type 1 VWD. A signi®cant proportion of patients, 102/246 (42%), remained an indeterminate group with blood type O, VWF levels between 35 and 50 U/dl and personal and/or family bleeding history. This subgroup might require reclassi®cation as`not VWD'.However, a similar bleeding tendency was found in two matched groups of patients of blood groups O and non-O and VWF levels between 35 and 50 U/dl. These results suggest that the use of ABO adjusted ranges for VWF levels might not be essential for diagnosis, because bleeding symptoms may depend on the VWF level regardless of the ABO type. Of the diagnostic criteria, the bleeding history was of prime importance in the clinical decision to diagnose and treat type 1 VWD. These observations could help in the reconsideration of how the criteria for diagnosing type 1 VWD could be adjusted in order to maximize their clinical relevance.

High prevalence of bleeders of unknown cause among patients with inherited mucocutaneous bleeding. A prospective study of 280 patients and 299 controls

“…25 Accordingly, assuming that the low VWF is the bleeding risk factor, we established the reference ranges without considering the ABO blood type, as suggested. 26 Fifty patients had VWD, 45 of them had type 1, two had type 2A and three had type 2B. Considering one patient excluded because of thrombocytopenic type 2B VWD, the prevalence of non-type 1 VWD phenotypes in our population is around 12%, lower than the 20-30% reported elsewhere.…”

The obstetric and gynaecological management of women with inherited bleeding disorders – review with guidelines produced by a taskforce of UK Haemophilia Centre Doctors’ Organization

“…Patients with blood type O have 25% lower VWF levels compared with other blood types [146] [147]. Therefore, the use of ABO adjusted ranges for VWF levels may not be necessary because bleeding symptoms seem to depend on the VWF level regardless of the blood type.…”

Acquired Disorders of Platelet Function

“…Of several criteria for a positive bleeding history, 2,3 The International Society on Thrombosis and Hemostasis suggests that bleeding should be considered clinically significant when there are two or more distinct bleeding sites such as the skin, nose, gums, vagina, gastrointestinal tract, or genitourinary tract; this includes spontaneous bleeding as well as provoked bleeding, such as occurs with dental work, parturition, trauma or surgery. A bleeding history is also considered significant when there is only a single bleeding site so severe that it leads to red cell transfusions.…”