Coagulopathies: abnormal blood-clotting and bleeding disorders

Platelets and blood-clotting factors are critical for haemostasis, which is the prevention of unwanted blood loss, usually following injury or trauma. Coagulopathies can manifest as either abnormal clotting or abnormal bleeding. Pathologies that cause abnormal clotting include thromboses in arteries or emboli from deep vein thromboses; these can both restrict blood flow to vital organs. A hypercoagulable state, such as factor V Leiden, can increase the risk of developing such blood clots. Pathologies that can cause abnormal bleeding include haemophilia and von Willebrand disease. Finally, disseminated intravascular coagulation presents as both abnormal blood clotting and abnormal bleeding; it can be a life-threatening complication of many conditions, including sepsis.

This article has been double-blind peer reviewed

In this article…

• The physiology of haemostasis and the clotting factor cascade

• Coagulopathies that can cause abnormal blood clotting and bleeding

• The conditions' causes, risk factors, symptoms and management

Key points

On injury, platelets form a plug to reduce blood loss

Once a plug has been formed by platelets, a cascade of clotting factors is activated, culminating in a more robust fibrin clot

Coagulopathies are conditions that adversely affect blood-clotting activities

Thrombosis and hypercoagulable states can cause abnormal blood-clot formation

Thrombocytopenia, haemophilia, von Willebrand disease and vitamin K deficiency can cause abnormal bleeding