Acquired von willeebrand disease in hematologic malignancies at the national cancer institute (NCI)‎ Egypt

الملخص EN

Acquired von Willebrand disease (AvWD) is an acquired bleeding disorder, which may suddenly become manifest in individuals, in the absence of a past personal or family history of bleeding and frequently in association with monoclonal gammopathies, lymphoproliferative, myeloproliferative and autoimmune disorders.

In a minority of cases AvWD may develop in association with drugs or solid tumors.

One hundred and fourteen patients attending to the Medical Oncology Department, NCI, presenting with a recent development of non-thrombocytopenic mucocutaneous bleeding were included in the study.

Due to the limitations and variability of each assay and because of vWD heterogeneity, no single test procedure was sufficiently robust to permit detection of all subtypes.

However, this is not the case in AvWD, since the most common pattern observed is deficiency of large vWF multimers 20 / 39.

In this regard, the multimer analysis would depict most of the cases.

Four separate assays for vWF were included : vWF ; Multimer analysis, vWF ; Antigen (vWF : Ag), factor eight coagulant activity (FVIIIc) and Ristocetin cofactor (vWF : RiCof).

39 / 114 cases were diagnosed as AvWD (17 CML,11 NHL, 8 CLL and 3 MM).

The 39 cases of AvWD were subclassified : 3 cases as type 1, 20 cases as type 2A, 8 cases as probable type 2N, 7 cases as probable type 2M (based on the low Ri : Cof / vWF : Ag ratio < 0.36) and 1 case as AvWD (unrecognized subtype).

The increased incidence of AvWD in CML patients was statistically significant (p = 0.04).

Using receiver operator characteristic (ROC) analysis, the best diagnostic single test was found to be RiCof, followed by FVIIIc, APTT and lastly vWF : Ag.

Although patients with blood group O were most frequently and significantly (p = 0.046) affected when the multimer test was used, this turned insignificant when the Ri : Cof test was analyzed.

This could be relevant to the normal distribution of blood groups among the population rather than to the inherent low level of vWF : Ag in blood group O individuals.

This report emphasizes that AvWD is not an extremely rare disorder, particularly in the setting of hematologic malignancies in Egypt