What is a coagulation disorder?

Coagulation disorders are conditions, most often hereditary and congenital, that affect the normal blood clotting process. They include haemophilia, von Willebrand disease, and other rare coagulation factor deficiencies.

Haemophilia exists in two forms: haemophilia A, which involves a deficiency in coagulation factor VIII, and haemophilia B, which involves a deficiency in factor IX. Its clinical manifestations affect primarily men.

Von Willebrand disease is the most common hereditary coagulation disorder. It is caused by a quantitative or qualitative deficiency of von Willebrand factor, a protein essential for platelet adhesion to the walls of damaged blood vessels. Unlike haemophilia, it affects both women and men. Several types exist (Type 1, 2 and 3), of variable severity.

Other rare coagulation disorders can also occur, involving deficiencies in other factors (factors I, II, V, VII, X, XI, XIII, among others). Although less frequent, they require equally specific management.

Regardless of the type of coagulation disorder, the degree of severity must be distinguished. Some patients have a significant or total deficiency of the relevant factor; others have a moderate or mild deficiency. The type of disorder and the degree of severity largely determine the patient's treatment.

People with a coagulation disorder experience abnormally longer bleeding than other individuals. In most cases, external bleeds related to everyday scratches and minor injuries are benign and require classic compression measures. Patients with von Willebrand disease may also experience frequent mucosal bleeding (nosebleeds, gum bleeding, heavy periods in women).

However, the most serious bleeds in a patient with a coagulation disorder occur internally, either at the joints (haemarthroses), in the muscles (haematomas), or in soft tissues. Haemarthroses and haematomas are particularly frequent in severe forms of haemophilia, while von Willebrand disease manifests more through mucocutaneous bleeding, although joint bleeding can occur in the most severe forms (Type 3).

Internal bleeds are often spontaneous in patients with severe forms, who are generally very well informed about the treatment to follow and have the required capacity to treat themselves. Some patients with a severe form, particularly children, are also treated preventively (prophylaxis), in order to reduce the frequency of spontaneous bleeds.

In the event of a major accident and/or loss of consciousness in a patient with a coagulation disorder, whether they have a severe, moderate or mild form, it is absolutely essential for healthcare staff to take into account the risk of internal bleeding and to consult, as quickly as possible, a reference centre specialising in coagulation disorders, preferably the one where the patient is known, in order to take the necessary precautions.

Reference centres

Each patient has a card on the back of which are the contact details of their Treatment Centre.

In case of emergency, contact them!