Bleeding disorders are a group of conditions involving the body's blood clotting process. Such disorders can lead to heavy and prolonged bleeding after an injury.

Normal blood clotting involves as many as 20 different plasma proteins, which are known as blood clotting or coagulation factors. These factors act together with other chemicals to form a substance called fibrin that stops bleeding.

Problems can occur when certain coagulation factors are low or missing. Bleeding problems can range from mild to severe.

Some bleeding disorders are present at birth and are passed through families (inherited). Others develop during certain illnesses (such as vitamin K deficiency or severe liver disease), or treatments (such as the use of drugs to stop blood clots (anticoagulants) or the long-term use of antibiotics).

Bleeding disorders can also result from having poorly working or too few of the blood cells that promote blood clotting (platelets). These disorders can also be either inherited or picked up (acquired). The side effects of certain drugs often lead to the acquired forms.

• Abnormal menstrual bleeding
• Bleeding into joints
• Excess bruising
• Heavy bleeding
• Nose bleeds

See also:

• Congenital antithrombin III deficiency
• Congenital protein C or S deficiency
• DIC (disseminated intravascular coagulation)
• Drug-induced immune thrombocytopenia
• Factor II deficiency
• Factor V deficiency
• Factor VII deficiency
• Factor X deficiency
• Factor XII deficiency
• Hemophilia A
• Hemophilia B
• Idiopathic thrombocytopenic purpura (ITP)
• Von Willebrand's disease (type I and type II)

• Complete blood count may show low platelets or anemia
• Prothrombin time (PT) may be longer
• Partial thromboplastin (PTT) time may be longer
• Bleeding time may be longer
• Platelet aggregation test may be abnormal

Which abnormalities occur depends on the bleeding disorder.

Treatment depends on the type of disorder. It may include factor replacement, fresh frozen plasma transfusion, platelet transfusion, or other therapies.

The outcome also depends on the disorder. Most primary bleeding disorders can be managed. Those due to diseases, such as DIC, depend on how well the disease is treated.

• Severe bleeding
• Bleeding in the brain

Other complications can result, depending on the disorder.

Call your health care provider if you notice any unusual or severe bleeding.

Prevention depends on the specific disorder.

Kumar V, Fausto N, Abbas A. Robbins & Cotran Pathologic Basis of Disease. 7th ed. Philadelphia, Pa: Saunders, 2004.

Hoffman R, Benz E, Shattil S, Furie B, Cohen H. Hematology: Basic Principles and Practice. 4th ed. Philadelphia, Pa: Churchill Livingstone, 2004.

Soliman DE, Broadman LM. Coagulation defects. Anesthesiol Clin North America. December 2006;24:549-578.