Coagulation disorders

General: In general, patients with anticoagulation disorders suffer from either increased bleeding or clotting. However, patients with disseminated intravascular coagulation may have symptoms of both bleeding and clotting.

Increased clotting: Symptoms depend on which blood vessels are blocked with clots.

If a blood vessel in an arm or leg is blocked, it may cause swelling and pain. The area may also become itchy and reddish brown in color. When this happens, the skin may be easily injured, often resulting in an ulcer.

Pieces of blood clots from the veins in the legs, abdomen, or pelvis can travel through the bloodstream to the lungs and block major arteries. If blood vessels in the lungs are blocked, the condition is called a pulmonary embolism. Symptoms may include shortness of breath, wheezing, chest pain, increased heartbeat, leg swelling, dizziness, or coughing up blood. Patients who develop any of these symptoms should seek immediate medical treatment because a pulmonary embolism may lead to death.

If blood vessels in the liver are blocked, symptoms may include yellowing of the skin and eyes (jaundice) and abdominal tenderness. Patients who develop any of these symptoms should seek immediate medical treatment.

If blood vessels in the brain become blocked, the patient may suffer from a stroke. Symptoms may include sudden onset of numbness or weakness, difficulty speaking, confusion, difficulty seeing with one or both eyes, headache, dizziness, and imbalance. Patients who develop any of these symptoms should seek immediate medical treatment.

If arteries to the heart become clogged, the patient may have a heart attack. Symptoms may include chest pain or pressure, shortness of breath, nausea, weakness, as well as pain radiating to the arms, neck, or jaw, Patients who develop any of these symptoms should seek immediate medical treatment.

Small areas on the fingers or toes may turn black in color if fibrin, a component of blood clots, accumulates in the blood vessels.

Increased bleeding: Patients with bleeding disorders, such as hemophilia, bleed for prolonged periods of time after injury. It may take hours for a small cut or nosebleed (epistaxis) to stop without treatment.

Tiny red dots, called petechiae, may occur if there is bleeding under the skin. This condition is called purpura. Patients may bruise easily. The gums may bleed, and blood may appear in the stool or urine. Internal bleeding may cause the joints to swell and become painful.

Patients may develop internal bleeding that may lead to organ damage or even death. Internal bleeding may not cause any distinctive symptoms.

General: If a coagulation disorder is suspected, a healthcare provider will take a detailed medical history and perform a physical examination. It is important for patients to tell their healthcare providers if they are trying a new diet or taking any new drugs (prescription or over-the-counter), herbs, or supplements (e.g. aspiring, salicylate-containing agents, nonsteroidal anti-inflammatory drugs, or vitamin K) because they may be causing the disorder or worsening symptoms

Blood tests: Coagulation disorders are diagnosed after blood tests are performed. A sample of the patient's blood is analyzed for the presence of clotting factors, including platelets, vitamin K, Factor VIII, Factor IX, von Willebrand factor, and other blood proteins. Patients with abnormal levels of these proteins are diagnosed with coagulation disorders.

DNA analysis: A DNA analysis may be performed to determine whether or not the patient has inherited a disorder, such as hemophilia. During the procedure, a sample of blood is taken from the patient and sent to a laboratory for analysis. If a mutated gene associated with a specific disorder is present, a positive diagnosis is made.

Antibody testing: If it is suspected that the condition may be autoimmune-related, such as idiopathic thrombocytopenia, a healthcare provider will take a sample of the patient's blood to determine whether or not autoantibodies are present. Autoantibodies bind to the patient's own cells, causing the immune system to attack the body. If autoantibodies are present, the patient has an autoimmune disorder.

General: Coagulations disorders may be long-term inherited conditions, or they may be temporary conditions caused by surgery, severe injury, medications, or infections. Other factors, including age, weight, lifestyle, and coexisting medical conditions, may contribute to the development of coagulation disorders.

Thrombocytopenia: Thrombocytopenia is the most common cause of coagulation disorders. It is characterized by a lack of circulating platelets in the blood. Healthy individuals have anywhere from 150,000 to 450,000 platelets per microliter of circulating blood in the body. Thrombocytopenia occurs when the platelet count falls below 20,000 platelets per microliter of blood. The risk of bleeding increases as the number of platelets decreases. Mild thrombocytopenia often has no long-lasting effects. When there are less than 10,000 platelets per microliter of circulating blood, the condition is considered severe and internal bleeding (hemorrhage) may occur, especially in the brain or digestive tract.

Disseminated intravascular coagulation (DIC) is a type of thrombocytopenia that occurs when the blood coagulates through the entire body, which causes a depletion of platelets. This disorder has variable effects. It can result in either clotting symptoms or, more often, bleeding. Bleeding can be severe. DIC may be stimulated by many factors, including bacterial or fungal infections in the blood, severe tissue injury (such as burns or head trauma), cancer, surgery, reactions to blood transfusions, or childbirth complications (such as retained placenta after delivery). Individuals suffering from this condition have an increased risk of bleeding. This disorder is most common among critically ill patients.

Idiopathic thrombocytopenic purpura, also called immune thrombocytopenia, occurs when the immune system destroys platelets for an unknown reason. The body's immune system, which normally fights against disease and infection, attacks the platelets because they are mistaken for harmful invaders, such as bacteria. When the immune system mistakenly attacks body cells, the condition is called an autoimmune disease.

Thrombotic thrombocytopenic purpura (TTP) is a rare disorder that is characterized by low levels of platelets, low levels of red blood cells, as well as abnormalities in the kidneys and nervous system. This blood disorder causes blood clots to form in blood vessels throughout the body. Most cases of TTP are the result of a deficiency of the ADAMTS13 enzymes, which are involved in clotting. Not having enough of this enzyme causes platelets to clump together. In TTP patients, clots form throughout the body as platelets bind together abnormally and stick to blood vessel walls. As the platelets clump together, there are fewer platelets available in the bloodstream. This can lead to purpura, which occurs when bleeding under the skin causes purple-colored spots to appear on the skin. It may also cause red blood cells to break apart and be destroyed prematurely. The condition is considered a medical emergency because, if left untreated, it can lead to hemolysis and organ damage.

Drug-induced immune thrombocytopenia occurs when certain medications lead to the formation of antibodies that attack platelets. These antibodies bind to platelets and trigger other immune cells to destroy them. Some medications may cause the immune system to mistake the platelets for an invading substance and the antibodies set out to destroy the cells. As a result of this autoimmune response, platelets are removed rapidly from the blood circulation. Quinidine and quinine are the most common cause of the condition. However, both heparin and heroin have recently been indicated in an increasing number of reports.

Drug-induced non-immune thrombocytopenia occurs when a medication reduces the number of healthy platelets in the blood. This is not an immune-mediated reaction. Instead, the drugs either directly destroy the platelets or damage the bone marrow where platelets are produced. Medications, such as heparin, aspirin, quinidine, quinine, sulfa-containing antibiotics, some diabetes medications (e.g. diazoxide), gold salts, and rifampin, may destroy platelets.

Hemolytic uremic syndrome is a rare type of thrombocytopenia that causes a drastic decline in platelets, as well as the destruction of red blood cells and kidney damage. This condition has been caused by bacterial infections with Escherichia coli (E. coli). E.coli infections may develop after eating raw or undercooked meat, especially beef.

Hemophilia: Hemophilia, or hemophilia A (Factor VIII deficiency), is an inherited coagulation disorder that causes excessive bleeding. This disorder is inherited as an X-linked recessive trait. Males are affected almost exclusively because they have one X and one Y chromosome, while females have two X chromosomes. If a male inherits one mutated X chromosome, he will have the disease. Females,onthe other hand,need to inherit two X chromosomes in order to develop the condition. Although females who have only one mutated X chromosome do not have the disorder, they can pass the chromosome onto their children.

Hemophilia B, also called Factor IX deficiency or Christmas disease, is less common than hemophilia A. Patients with this disorder are born with low levels of a clotting factor called Factor IX. Without this factor, the blood is unable to clot properly.

Hemorrhagic disease of the newborn (vitamin K deficiency bleeding/VKDB): Hemorrhagic disease of the newborn is a bleeding disorder that occurs during an infant's first few days of life. This happens when a baby is born with low levels of vitamin K, which is an important element in the clotting cascade. Patients with this disorder experience increased bleeding until they have adequate levels of vitamin K in the blood. In order to prevent this condition, newborns are given an injection of vitamin K shortly after birth.

Von Willebrand's disease: Von Willebrand's disease is an inherited disorder that causes prolonged bleeding time. Patients are born with low or non-existent levels of a clotting factor called von Willebrand factor. In healthy patients, the platelets produce this clotting factor, which helps them stick to the blood vessel walls. Patients with this disease suffer from impaired platelet function.

Hypoprothrombinemia: Hypoprothrombinemia occurs when a patient is born with low or non-existent levels of a clotting factor called prothrombin. As a result, the patient experiences an increased risk of bleeding.

Hyperhomocysteinemia: Hyperhomocysteinemia occurs when a patient has high levels of an amino acid called homocysteine in the blood. As a result, the blood in the veins and arteries is more likely to clot.

Hyperhomocysteinemia may be inherited or it may be caused by low levels of vitamin B6, vitamin B2, or folic acid. Less common causes of hyperhomocysteinemia include chronic kidney failure and the use of certain medications, including an anti-cancer drug called methotrexate, some anti-seizure drugs (e.g. phenytoin or carbamazepine), some cholesterol-lowering drugs (e.g. fibric acid derivatives or niacin), and the antibiotic isoniazid.

Antiphospholipid syndrome: Antiphospholipid syndrome is a rare inherited disorder in which the body produces antibodies to proteins in the blood. Antiphospholipid syndrome may cause clots to form in the large veins of the legs and sometimes the arms. This potentially life-threatening condition is called deep vein thrombosis (DVT).

Obesity: Patients who are obese have an increased risk of developing blood clots because the extra body weight puts pressure on the veins, which slows the flow of blood. Also, physical activity in obese patients is limited. This may cause blood pooling, which leads to clot formations, especially in the legs.

Co-existing medical conditions: Certain medical conditions, including atherosclerosis (hardening of the arteries), arterial fibrillation, heart attack (myocardial infarction or MI), polyarteritis nodosa, which causes the blood vessels to swell, and giant cell arteritis, which causes the medium and large blood vessels in the head to swell, may make blood more likely to clot in the arteries. These disorders damage the arteries, which stimulate blood clot formation.

Immobility: Individuals who have sedentary lifestyles have an increased risk of developing blood clots. This is because sitting still for extended periods of time may slow blood flow, causing blood to accumulate in the veins, especially in patients who are at risk of developing blood clots. For instance, patients who are paralyzed or who are on bed rest for a long time have an increased risk of developing blood clots, especially in the deep veins in their legs. This condition is called deep vein thrombosis (DVT).

Even sitting still for several hours on an airplane or in a car may increase the risk of blood clots, especially DVT.

Age: The risk for blood clots increases with age. Men who are older than 55 years and women who are older than 60 years have the greatest risk of developing blood clots. The reason for this remains unknown. Some researchers suggest that the increased risk of blood clots in the arteries may be associated with an increased risk of atherosclerosis (hardened arteries).