The prognosis may be favorable with other causes of aVWS, for instance in aVWS patients with hypothyroidism, in whom treatment with thyroxine results in normalization of VWF.33 Also, in patients with myeloproliferative neoplasm who present with aVWS due to high platelet counts, cytoreductive therapy will normalize VWF levels and function.55,56 The mortality of patients with aVWS is mostly dependent upon the underlying cause, and no data on fatality rates due to bleeding is available. This evidence concerns the gene VWF and hypothyroidism.