Bleeding disorders are a group of conditions in which there is a problem with the body's blood clotting process. These disorders can lead to heavy and prolonged bleeding after an injury. Bleeding can also begin on its own.

See also:

• Acquired platelet function defects
• Congenital platelet function defects
• Congenital antithrombin III deficiency
• Congenital protein C or S deficiency
• Disseminated intravascular coagulation (DIC)
• 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)

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 from:

• Illnesses such as vitamin K deficiency or severe liver disease
• 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
• Excessive bruising
• Heavy bleeding
• Nosebleeds

Which problems occur depends on the specific bleeding disorder.

• Complete blood count (CBC)
• Bleeding time
• Partial thromboplastin time (PTT)
• Platelet aggregation test
• Prothrombin time (PT)

Treatment depends on the type of disorder. It may include:

• Factor replacement
• Fresh frozen plasma transfusion
• Platelet transfusion
• 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.

• Bleeding in the brain
• Severe bleeding (usually from the gastrointestinal tract or injuries)

Other complications can occur, depending on the disorder.

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

Prevention depends on the specific disorder.

Kessler C. Hemorrhagic disorders: Coagulation factor deficiencies. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 180.