Also Known As
Coagulopathy
This article was last reviewed on
This article waslast modified on
March 14, 2018.
What is a bleeding disorder?

A bleeding disorder is a tendency to bruise easily or bleed excessively or for prolonged periods. It may be the result of inheriting certain forms of genes (alleles) or caused by conditions or factors that develop within a person's lifetime (acquired).

Normally, blood remains in the circulatory system inside the blood vessels. When there is an injury to a blood vessel and bleeding begins, the body stops the blood loss through a complex clotting process called hemostasis. During primary hemostasis, the injured blood vessel constricts to reduce blood flow and small cell fragments in the blood called platelets adhere to the injury site, clump together with other platelets (aggregation), and release chemical compounds that stimulate further aggregation of other platelets to form a loose platelet plug.

At the same time, platelets support the initiation of the coagulation cascade, a series of steps that involve the sequential activation of proteins in the blood called clotting factors (coagulation factors). This secondary process results in the formation of strands of fibrin that weave through the loose platelet plug and compress to form a stable blood clot. This barrier prevents additional blood loss and remains in place until the injured area is healed.

Hemostasis is a dynamic process, though, so once a clot is formed, certain factors are activated to slow the clotting process. They eventually begin to dissolve the clot in a process called fibrinolysis so that the clot is removed when the injury site is healed. In normal, healthy individuals, this balance between clot formation and dissolution ensures that bleeding does not become excessive and that clots are removed once they are no longer needed.

Each component of primary and secondary hemostasis must be present, activated at the right time, and functioning properly for adequate clotting. If there are insufficient platelets or coagulation factors, or if platelets or coagulation factors are not functioning normally, a stable clot may not form and a person may be at an increased risk of excessive bleeding.

Bleeding disorders occur when something goes wrong with the clotting process, for example, when a component is missing, deficient, or not functioning properly. Disorders may involve problems with the structure of the blood vessels, the production or function of platelets or one or more of the coagulation factors, and/or the integrity and stability of the blood clot.

Inherited bleeding disorders are uncommon and tend to be caused by a deficiency or dysfunction of a single coagulation factor or clotting component. Acquired bleeding disorders, those with no genetic component, are varied and occur more frequently than inherited disorders.

Accordion Title
Types of Bleeding Disorders
  • Structural Problems with Blood Vessels

    Excessive bleeding and bruising may be the result of blood vessels that have not formed properly or do not function as they should. The following are a few examples:

    Inherited

    • Hemorrhagic Telangiectasia – blood vessels are more fragile than usual, leading to recurrent bleeding episodes; this rare disease affects approximately 1 in 50,000 people.
    • Ehlers-Danlos syndrome – collagen that supports blood vessels is unusually weak and elastic, making blood vessels less protected and more prone to injury; this disease affects 1 in 10,000 to 20,000 people.


    Acquired

    • Henoch-Schonlein purpura (allergic purpura) – small blood vessels are inflamed and prone to leakage, a condition thought to be an autoimmune response, and may be acute or chronic
    • Infectious purpura – blood vessels may be damaged directly by microorganisms or by toxins produced by them; examples of causes include infections with Streptococcus, Staphylococcus or meningococcus bacteria and Rocky Mountain Spotted Fever.
    • Metabolic purpura – caused by a defect in metabolism; one example is vitamin C deficiency, also called scurvy. This condition results in small blood vessels that have weakened walls due to a defect in collagen synthesis, typically manifesting as gum bleeding. It is much less common now than it was a few hundred years ago but can still be seen in areas of extreme poverty or war.
  • Platelet Disorders

    Bleeding disorders may arise from problems with platelets, either from a low count in the blood or from dysfunctional platelets. A CBC, which includes a platelet count, may reveal a low number while platelet function tests may indicate that dysfunctional platelets are present. Several follow-up tests may be required to determine the cause.

    Platelet deficiency (thrombocytopenia)

    A number of conditions and factors can cause a low platelet count, also called thrombocytopenia. The causes typically fall into one of two general categories:

    • Disorders in which the bone marrow cannot produce enough platelets
    • Conditions in which platelets are used up (consumed) or destroyed faster than normal


    Examples of conditions in which a low platelet count is due to the bone marrow not producing enough include:

    • Cancer such as leukemialymphoma or another type that has spread to the bone marrow may affect the production of platelets by the bone marrow. As the number of cancer cells increases in the bone marrow, normal bone marrow cells are crowded out, resulting in fewer platelet-producing cells.
    • Aplastic anemia – with this condition, the production of all blood cells is significantly affected.
    • Chemotherapy or radiation therapy, which may affect the bone marrow

    Examples of conditions in which platelets are used up or destroyed faster than normal include:

    • Idiopathic (immune) thrombocytopenia, also called idiopathic thrombocytopenic purpura (ITP), is caused by an autoantibody produced against platelets. It is one of the most common causes of low platelets. Acute ITP occurs more often in youth, is usually short-term, and typically follows a viral infection. This condition may resolve without treatment. Chronic ITP develops more slowly, typically lasts longer than 6 months, and occurs more often in adults. Because of the duration of the disease, this form often requires treatment.
    • Certain drugs such as acetaminophen, quinine, sulfa antibiotics, digoxin, vancomycin, valium, nitroglycerine and gold salts are just a few examples that have been associated with a decrease in the number of platelets.
    • Disease-related:
    • Massive blood (red blood cells) transfusion without giving platelets (thrombocytopenia due to dilution effect)

    Other conditions that may be associated with low platelet count:

    There are conditions that may cause low platelets, though bleeding may not result. Examples include:

    • Heparin-induced thrombocytopenia (HIT) results in low platelets when a person who is on or received heparin therapy develops an antibody. However, HIT is often associated with clotting, rather than bleeding. (For more on this, see the article on HIT Antibody).
    • Thrombotic thrombocytopenic purpura (TTP) is an acute, potentially life-threatening though rare condition. It causes both clotting and destruction of red blood cells. Tiny clots form and deposit in small blood vessels throughout the body. This clotting uses up platelets at an accelerated rate, leading to a low number of platelets.


    Platelet dysfunction

    The conditions and factors resulting in platelet dysfunction are either inherited or the result of some other disease or condition (acquired).

    Examples of inherited platelet function disorders include:

    • Glanzmann thrombasthenia – affects platelets' ability to clump (aggregate)
    • Bernard-Soulier syndrome – characterized by reduced platelet adhesion
    • Storage pool disease – can affect platelet ability to release substances that promote aggregation


    Acquired platelet dysfunction – those that are not inherited – may be due to chronic conditions or factors such as:

  • Coagulation Factor Deficiency or Dysfunction

      A bleeding disorder may be due to a lack of one or more clotting factors or the result of factors that do not function properly. Deficiency or dysfunction of coagulation factors may have genetic causes (inherited) or may be the result of another disease or condition. The following are a few examples:

      Inherited

      Von Willebrand disease (VWD): this condition is associated with decreased production or dysfunction of von Willebrand factor and results in reduced platelet adherence to the injured blood vessel and increased blood loss. VWD is the most common inherited bleeding disorder, affecting as many as 1 in 100 people. Rarely, VWD may be due to an acquired VWF deficiency, where there is no family or personal bleeding history up to the point of presentation.

      VWD is separated into different types and sub-types, including:

      • Type 1 – with this type of VWD, there is a decrease in the amount of VWF produced, but the VWF functions normally. Levels of factor VIII are also typically low but may be normal. This is the most common type of VWD, accounting for about 75% of cases. It tends to cause bruising and mild to moderate bleeding, such as frequent nosebleeds, heavy menstrual periods, and prolonged bleeding following childbirth, trauma, dental procedures, and surgeries. Symptoms and the severity of bleeding will vary from person to person and from episode to episode.
      • Type 2 – this type is typically associated with a normal amount of VWF, but the VWF does not function normally. Bleeding may be more severe with this type. There are four different subtypes, each caused by unique defects in VWF. Type 2 VWD accounts for 15-20% of all VWD cases.
      • Type 3 – this rare type is associated with little to undetectable VWF production, very low factor VIII levels, and moderate to severe bleeding. It is often detected in infancy because of early bleeding episodes.


      Hemophilia A (Factor VIII deficiency): This is an X-chromosome linked recessive bleeding disorder that occurs primarily in males. It is the second most common inherited bleeding disorder. Worldwide, about 1 in 5,000 males are born with hemophilia. (For more on inheritance, see The Universe of Genetic Testing.)

      In those with the disease, the first bleeding episode may be with circumcision or other procedures performed on an infant. The severity of the bleeding caused by a factor VIII deficiency depends on its activity level. 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.

      Other inherited factor deficiencies include II, V, VII, X, XI, and IX (hemophilia B, also called Christmas disease, which is also X-linked and occurs in approximately 1 in 25,000 males).

      Acquired

      • Acute liver failure – almost all coagulation factors are produced in the liver; liver disease may result in decreased production of factors.
      • Vitamin K deficiency – the synthesis of several coagulation factors (II, VII, IX, X) requires vitamin K.
      • Exposure to certain snake venom
      • Some cancers
      • Treatment for cancer, such as chemotherapy or radiation therapy
      • Massive blood transfusions (e.g., transfuse only red blood cell units)
      • Factor inhibitors are antibodies that target a specific clotting factor, such as factor VIII, decreasing its activity.
      • Anticoagulant drugs such as warfarin (COUMADIN®) or heparin; these drugs are used to treat clotting disorders but in excessive amounts may cause bleeding.
      • Some bacterial infections
      • Disseminated intravascular coagulation (DIC), may cause both bleeding and clotting (thrombosis). It is usually an acute condition, may be from a complicated childbirth, from an endotoxin produced during a severe infection, or due to certain cancers such as a certain type of leukemia. DIC causes tiny clot formation throughout the body, using up clotting factors at an accelerated rate, leading to excessive bleeding.
    • Excessive Clot Breakdown

      Fibrinolysis is a process that prevents blood clots from growing and becoming problematic. In fibrinolysis, a fibrin clot, the product of the coagulation cascade, is broken down by a factor called plasmin. Normally, an activator (which converts inactive plasminogen to active plasmin) is released into the blood very slowly by the damaged lining (endothelium) of the blood vessels, such that, after several days (when the bleeding has stopped and injury healed), the clot is broken down.

      The fibrinolytic process is tightly regulated by several other factors, especially plasminogen activator inhibitor (PAI) and plasmin inhibitor (e.g., alpha2-antiplasmin). If there is an inherited or acquired deficiency in one of the inhibitors, the fibrinolytic activity is enhanced. As a result, the clot is not as stable as it should be and is broken down early, causing excessive or prolonged bleeding, which typically occurs after an injury or invasive procedure (e.g., tooth extraction, surgery).

    Accordion Title
    More about Bleeding Disorders
    • Signs and Symptoms

      Bleeding disorders may cause a wide range of signs and symptoms, depending on the cause. Several different combinations of signs and symptoms may be present with varying degrees of severity that changes over time. Bleeding may be severe, with episodes beginning in early childhood, or relatively mild, involving prolonged bleeding following surgery, dental procedures, or trauma. When bleeding episodes begin early in life and/or when a close relative has an inherited factor deficiency, an inherited bleeding disorder should be suspected.

      Some signs and symptoms may include:

      • Unexplained or easy bruising
      • Frequent nosebleeds
      • Bleeding gums
      • Prolonged bleeding from small cuts or after dental procedures
      • In women, heavy menstrual periods that last longer than average
      • Joint and/or muscle pain or swelling after minor accident or injury
      • Small red spots on the skin (petechiae); may sometimes look like a rash
      • Small purplish spots on the skin (purpura) or large purplish lesions (ecchymosis) caused by bleeding under the skin
      • Blood in the stool; bleeding from the digestive tract
      • Arthritic-type symptoms from damage from bleeding into joints
      • Loss of vision with bleeding in the eyes
      • Chronic anemia (often iron deficiency anemia)
    • Tests

      If a healthcare practitioner suspects that a person's signs and symptoms are due to a bleeding disorder, the practitioner may order several laboratory tests. The investigation of a bleeding disorder is usually a step-by-step process. A healthcare provider may begin by ordering tests such as: 

      The following table summarizes some of the tests that may be done in the investigation of a bleeding disorder. Not all of the tests listed in the table are needed for each person with a suspected bleeding disorder. The tests are listed in alphabetical order; for detailed information about each test, click on the name of the test to go to the specific article.

      Tests for Bleeding Disorders

      The tests listed here are some of the more common tests performed to evaluate bleeding disorders.

      Test Description Reason for testing possible significance of Abnormal Results
      Blood Smear Microscopic examination of blood; estimates the number and evaluates appearance and size of platelets If a person is experiencing unexplained bleeding; if a platelet count is abnormal Abnormal platelets may indicate a platelet disorder
      CBC (Complete Blood Count) Counts the different types of blood cells, including platelets, red blood cells (RBCs), and white blood cells (WBCs), types of WBCs; measures hemoglobin and hematocrit Routine screen and general test to check for any abnormalities; detects anemia Decreased platelets may indicate a platelet disorder; anemia may indicate excessive bleeding 
      Coagulation Factors, Activity Individual tests to measure the activity (function) of specific coagulation factors If PT or PTT results are abnormal Decreased activity of one or more factors may indicate factor deficiency or specific factor inhibitor
      Coagulation Factors, Antigen Measures the amount of individual factors When the activity of a specific factor is consistently low Low level may indicate factor deficiency due to decreased production or increased consumption of a factor
      D-dimer Measures a specific type of cross-linked fibrin degradation product Evaluate blood clot formation during bleeding and clotting episodes If elevated, indicates recent clotting activity; may be due to conditions, such as a blood clot (thrombosis) or disseminated intravascular coagulation (DIC)
      Factor Inhibitors Detects antibodies directed against individual coagulation factors If coagulation factor activity test is abnormal If present, may cause specific factor deficiencies and excessive bleeding
      Fibrinogen (activity) Reflection of clotting ability and activity Evaluate bleeding and clotting If low, may indicate decreased production or increased use; may be elevated with infection and inflammation.
      Partial Thromboplastin Time (PTT) A general screen that evaluates factors XII, XI, IX, VIII, X, V, II (prothrombin), and I (fibrinogen) as well as prekallikrein (PK) and high molecular weight kininogen (HMWK) Investigate bleeding
       
      Prolonged PTT suggests need for further tests; may indicate
      coagulation factor deficiency,
      specific inhibitor (such as Factor VIII antibody), nonspecific inhibitor (such as lupus anticoagulant)
      Platelet Function Tests (aggregation study) Evaluate platelets' ability to adhere and form clumps (aggregate) Evaluate bleeding, especially when platelet count is normal If abnormal, may indicate presence of one of several disorders including von Willebrand disease
      Prothrombin Time (PT) A general screen that evaluates factors VII, X, V, II, and I (fibrinogen) Investigate bleeding Prolonged PT may suggest need for further tests; may indicate coagulation factor deficiency or dysfunction, or specific factor inhibitor
      Ristocetin Cofactor Indirect measure of von Willebrand factor (VWF) activity/function Evaluate bleeding episodes If decreased, may indicate low VWF activity and decreased ability for platelets to adhere to injuries; may be due to von Willebrand disease
      Thrombin Time (TT) Thrombin activates fibrinogen to fibrin stands; TT detects presence of inhibitors to this process Help evaluate bleeding episode; sometimes when PTT prolonged; when heparin contamination of sample suspected If elevated, heparin may be contaminating blood sample; also elevated with presence of fibrin degradation products, with very low levels of fibrinogen, and with abnormal fibrinogen (e.g., dysfibrinogenemia)
      von Willebrand Factor (VWF) Antigen Measures amount of VWF When activity (measured as Risocetin Cofactor) is low; evaluate bleeding episodes If low, may indicate platelet-related acquired condition or von Willebrand disease, increased risk of bleeding
      Thromboelastography (TEG) Overall assessment of clotting abilities, including the function of platelets, coagulation factors, and clot breakdown When there is need to assess the potential cause of excessive or prolonged bleeding during and after major surgery (e.g., cardiopulmonary bypass) Abnormal result(s) could be due to quantitative or qualitative defect in platelets, coagulation factors, and/or fibrinolytic factors. The results are useful in guiding patient's management, particularly blood product transfusion.

      Basic metabolic panels may be ordered to assess the liver and kidney functions. Patients with liver and/or kidney failure have increased risk of bleeding.

    • Treatment

      Treatment for a bleeding disorder depends on the cause, whether it is an acquired or inherited condition, as well as on the duration and severity of signs and symptoms. Typically, bleeding disorders are identified, monitored, and controlled both to prevent excessive blood loss and to prevent complications that may arise. The degree and frequency of treatment needed will depend on the severity of the deficiency or condition, whether or not there is a stimulus for bleeding such as surgery or trauma, and whether or not the condition progresses or worsens over time.

      Sometimes simply avoiding injury, limiting physical contact sports for instance, may be enough to minimize bleeding episodes in those with mild conditions, and under most circumstances, in those with moderate bleeding tendencies.

      If a bleeding disorder is due to an acquired condition, it may improve or worsen as the underlying condition is resolved or progresses. If, for instance, factor deficiencies are due to a lack of vitamin K, they may return to normal with vitamin supplementation. If they are due to liver disease or to a cancer, they will likely follow the course of the disease.

      For more information on treatment of bleeding disorders, see the links in the Related Content section below.

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