Bleeding disorders

What is it?
Structural defects
Factor defects
Laboratory tests
Treatments

Coagulation factor deficiency or dysfunction

Inherited

Haemophilia A (Factor VIII deficiency) -- X-chromosome linked bleeding disorder that occurs primarily in males. The first bleeding episode may be with circumcision or other procedure as an infant. The severity of the bleeding caused by a factor VIII deficiency depends on its activity level (how well it is functioning). If it is very low it may cause severe life threatening bleeding, if it is moderate it may only cause mild to moderate bleeding – becoming an issue primarily when having surgery or dental procedures.

von Willebrand’s disease -- relatively common, resulting from defective or missing von Willebrand factor. Von Willebrand factor is a protein that adheres platelets to the site of a blood vessel injury. It is associated with factor VIII: if VIII is deficient then vWF may be affected.

Other factor deficiencies -- II, V, VII, IX, X, (Haemophilia B, also called Christmas disease)

Acquired:

Liver dysfunction or disease
Vitamin K deficiency
Fat malabsorption
Snake venom
Therapy for bone marrow and myeloproliferative disorders
Factor inhibitors (antibodies that target a specific clotting factor, such as factor VIII, decreasing its level and making factor replacement more of a challenge)
Anticoagulant drugs: such as coumadin (warfarin) or heparin, these drugs are used to treat clotting disorders but in excessive amounts may cause bleeding
Some bacterial infections
DIC (disseminated intravascular coagulation), may cause both bleeding and clotting. It is usually an acute condition, for example from a complicated childbirth – as a result of uterine tissue contacting the blood stream, from an endotoxin produced during a severe infection, or due to certain cancers such as leukaemia. DIC causes tiny clot formation throughout the body, using up clotting factors at an accelerated rate – leading to excessive bleeding.