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Description of von Willebrand Disease

This is an autosomal dominant inherited disease – a coagulopathy (blood clotting disorder) characterized by a deficiency of factor VIII in clotting and impaired platelet function. Both men and women are affected, with an incidence of 2 cases per 100,000 individuals. Higher incidence in Scandinavian countries, Israel, and Iran. In Lithuania, it is a relatively rare disease, possibly due to inadequate diagnostics, where it ranks third after Hemophilia A and platelet disorders.

In von Willebrand disease, there is a disruption in the synthesis of the VIII factor’s vWF component synthesis (vWF – a large glycoprotein produced by megakaryocytes, endothelial cells; its function is to control platelet adhesion to the endothelium, it is the main carrier of VIII factor, preventing VIII factor from being removed from circulation).

When there is a mutation in the vWF gene, different types of von Willebrand disease are revealed:

a) the first type (classic) – when vWF production is disrupted. Its structure remains unchanged, only the quantity decreases.

b) the second type A – changes in the multimeric vWF structure, leading to a lack of platelet adhesion to the endothelium, decreased ristocetin-induced platelet aggregation.

c) the second type B – increased ristocetin-induced platelet aggregation.

d) the second types N and M – abnormal vWF molecule cannot bind to VIII factor.

e) the third type – there is neither VIII factor nor vWF in the blood plasma.

Symptoms

The disease manifests in children under the age of 3 and lasts a lifetime. It presents with recurrent bleeding from the nose, gums, into the joints, muscles, gastrointestinal tract, kidneys, other organs, and the formation of hematomas (localized collections of extravasated blood within tissues). Examination of individuals who bleed frequently reveals vascular lesions prone to bleeding. Bleeding from vascular dysplasias is dangerous as it can be abundant, profuse, and difficult to stop.

For women with this disease, pregnancy and childbirth are complicated, and for girls, the first menstruations are very dangerous.

Diagnosis

Prolonged bleeding time is determined, along with impaired platelet aggregation with ristocetin (aggregation with collagen, thrombin, adrenaline is normal). The coagulation activity of factor VIII, its protein levels are decreased, vWF levels are also reduced or absent. Prothrombin time is normal or prolonged.

Treatment

Patients take preparations with factor VIII every 24-36 hours. Sometimes desmopressin is effective when there is mild bleeding, it can be administered as nasal drops. Aminocaproic acid is also suitable for minor bleeding.

In cases of prolonged uterine bleeding outside menstruation (metrorrhagia) or prolonged heavy bleeding during menstruation (menorrhagia), gestagen preparations are prescribed. It is not advisable to combine aminocaproic acid, gestagens, and cryoprecipitate due to the risk of DIC syndrome.

DIC (disseminated intravascular coagulation) is a condition where numerous microthrombi form, causing organ damage.

In later stages of DIC syndrome, due to extensive intravascular coagulation, platelets are consumed, coagulation factors are activated, fibrinolysis occurs, leading to a hemorrhagic syndrome exacerbated by a deficiency of plasma coagulation factors, thrombocytopenia, and developing anemia. Petechiae, ecchymoses, hematomas in muscles, bleeding from needle puncture sites, surgical wounds, mucous membranes appear on the skin.

Source | Author Doctor Nikas Samuolis, reviewed by Prof. Virginijus Šapoka | Vilnius University | Faculty of Medicine | Head of the Department of Internal Medicine, Family Medicine, and Oncology