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There is no specific treatment for thrombophilia, unless it is caused by an underlying medical illness (such as nephrotic syndrome), where the treatment of the underlying disease is needed. In those with unprovoked and/or recurrent thrombosis, or those with a high-risk form of thrombophilia, the most important decision is whether to use anticoagulation medications, such as warfarin, on a long-term basis to reduce the risk of further episodes. This risk needs to weighed against the risk that the treatment will cause significant bleeding, as the reported risk of major bleeding is over 3% per year, and 11% of those with major bleeding may die as a result.
Apart from the abovementioned forms of thrombophilia, the risk of recurrence after an episode of thrombosis is determined by factors such as the extent and severity of the original thrombosis, whether it was provoked (such as by immobilization or pregnancy), the number of previous thrombotic events, male sex, the presence of an inferior vena cava filter, the presence of cancer, symptoms of post-thrombotic syndrome, and obesity. These factors tend to be more important in the decision than the presence or absence of a detectable thrombophilia.
Those with antiphospholipid syndrome may be offered long-term anticoagulation after a first unprovoked episode of thrombosis. The risk is determined by the subtype of antibody detected, by the antibody titer (amount of antibodies), whether multiple antibodies are detected, and whether it is detected repeatedly or only on a single occasion.
Women with a thrombophilia who are contemplating pregnancy or are pregnant usually require alternatives to warfarin during pregnancy, especially in the first 13 weeks, when it may produce abnormalities in the unborn child. Low molecular weight heparin (LMWH, such as enoxaparin) is generally used as an alternative. Warfarin and LMWH may safely be used in breastfeeding.
When women experience recurrent pregnancy loss secondary to thrombophilia, some studies have suggested that low molecular weight heparin reduces the risk of miscarriage. When the results of all studies are analysed together, no statistically signifiant benefit could be demonstrated.
As there is no cure, treatment is focused on prevention of thrombotic complications by counseling. In addition, temporary treatment with an anticoagulant may be required during periods of particularly high risk of thrombosis, such as major surgery.
Treatment for Thrombotic Storm may include lifelong anticoagulation therapy and/or thrombolytic therapy, plasmapherisis, and corticosteroids. Studies have shown that when anticoagulant therapy is withheld recurrence of thrombosis usually follows. INR is closely monitored in the course of treatment.
The course of treatment and the success rate is dependent on the type of TMA. Some patients with atypical HUS and TTP have responded to plasma infusions or exchanges, a procedure which replaces proteins necessary for the complement cascade that the patient does not have; however, this is not a permanent solution or treatment, especially for patients with congenital predispositions.
For people who have severe congenital protein C deficiency, protein C replacement therapies are available, which is indicated and approved for use in the United States and Europe for the prevention of purpura fulminans. Protein C replacement is often in combination with anticoagulation therapy of injectable low molecular weight heparin or oral warfarin. Before initiating warfarin therapy, a few days of therapeutic heparin may be administered to prevent warfarin skin necrosis and other progressive or recurrent thrombotic complications.
If someone has coagulopathy, their health care provider may help them manage their symptoms with medications or replacement therapy. In replacement therapy, the reduced or absent clotting factors are replaced with proteins derived from human blood or created in the laboratory. This therapy may be given either to treat bleeding that has already begun or to prevent bleeding from occurring.
Therapy involves both preventive measures and treatment of specific bleeding episodes.
- Dental hygiene lessens gingival bleeding
- Avoidance of antiplatelet agents such as aspirin and other anti-inflammatory drugs (NSAIDs) such as ibuprofen and naproxen, and anticoagulants
- Iron or folate supplementation may be necessary if excessive or prolonged bleeding has caused anemia
- Hepatitis B vaccine
- Antifibrinolytic drugs such as tranexamic acid or ε-aminocaproic acid (Amicar)
- Desmopressin (DDAVP) does not normalize the bleeding time in Glanzmann's thrombasthenia but anecdotally improves hemostasis
- Hormonal contraceptives to control excessive menstrual bleeding
- Topical agents such as gelfoam, fibrin sealants, polyethylene glycol polymers, custom dental splints
- Platelet transfusions (only if bleeding is severe; risk of platelet alloimmunization)
- Recombinant factor VIIa, AryoSeven or NovoSeven FDA approved this drug for the treatment of the disease on July 2014.
- Hematopoietic stem cell transplantation (HSCT) for severe recurrent hemorrhages
Often, this disease is treated by giving aspirin to inhibit platelet activation, and/or warfarin as an anticoagulant. The goal of the prophylactic treatment with warfarin is to maintain the patient's INR between 2.0 and 3.0. It is not usually done in patients who have had no thrombotic symptoms.
Anticoagulation appears to prevent miscarriage in pregnant women. In pregnancy, low molecular weight heparin and low-dose aspirin are used instead of warfarin because of warfarin's teratogenicity. Women with recurrent miscarriage are often advised to take aspirin and to start low molecular weight heparin treatment after missing a menstrual cycle. In refractory cases plasmapheresis may be used.
Warfarin and vitamin K antagonists are anticoagulants that can be taken orally to reduce thromboembolic occurrence. Where a more effective response is required, heparin can be given (by injection) concomitantly. As a side effect of any anticoagulant, the risk of bleeding is increased, so the international normalized ratio of blood is monitored. Self-monitoring and self-management are safe options for competent patients, though their practice varies. In Germany, about 20% of patients were self-managed while only 1% of U.S. patients did home self-testing (according to one 2012 study). Other medications such as direct thrombin inhibitors and direct Xa inhibitors are increasingly being used instead of warfarin.
Inferior vena cava filters (IVC filters) are used on the presumption that they reduce PE, although their effectiveness and safety profile are not well established. In general, they are only recommended in some high risk scenarios. The ACCP recommended them for those with a contraindication to anticoagulant treatment but not in addition to anticoagulation, unless an individual with an IVC filter but without a risk for bleeding develops acute proximal DVT. In this case, both anticoagulation and an IVC filter are suggested. NICE recommends caval filters in settings where someone with an acute proximal DVT or PE cannot receive anticoagulation, and that the filter is removed when anticoagulation can be safely started. While IVC filters themselves are associated with a long-term risk of DVT, they are not reason enough to maintain extended anticoagulation.
Thrombolysis is the administration of an enzyme (intravenous or directly into the affected vein through a catheter), which acts to enzymatically break up clots. This may reduce the risk of post-thrombotic syndrome by a third, and possibly reduce the risk of leg ulcers, but is associated with an increased risk of bleeding. The ACCP currently suggests anticoagulation rather than thrombolysis, but patients may choose thrombolysis if prevention of post-thrombotic syndrome outweighs concerns over the complexity, bleeding risk, and cost of the procedure. NICE recommends that thrombolysis is considered in those who have had symptoms for less than two weeks, are normally well, have a good life expectancy and a low risk of bleeding.
A mechanical thrombectomy device can remove venous clots, although the ACCP considers it an option only when the following conditions apply: "iliofemoral DVT, symptoms for < 7 days (criterion used in the single randomized trial), good functional status, life expectancy of ≥ 1 year, and both resources and expertise are available." Anticoagulation alone is suggested over thrombectomy.
Due to the high mortality of untreated TTP, a presumptive diagnosis of TTP is made even when only microangiopathic hemolytic anemia and thrombocytopenia are seen, and therapy is started. Transfusion is contraindicated in thrombotic TTP, as it fuels the coagulopathy. Since the early 1990s, plasmapheresis has become the treatment of choice for TTP. This is an exchange transfusion involving removal of the patient's blood plasma through apheresis and replacement with donor plasma (fresh frozen plasma or cryosupernatant); the procedure must be repeated daily to eliminate the inhibitor and abate the symptoms. If apheresis is not available, fresh frozen plasma can be infused, but the volume that can be given safely is limited due to the danger of fluid overload. Plasma infusion alone is not as beneficial as plasma exchange. Corticosteroids (prednisone or prednisolone) are usually given. Rituximab, a monoclonal antibody aimed at the CD20 molecule on B lymphocytes, may be used on diagnosis; this is thought to kill the B cells and thereby reduce the production of the inhibitor. A stronger recommendation for rituximab exists where TTP does not respond to corticosteroids and plasmapheresis.
Caplacizumab is an alternative option in treating TTP as it has been shown that it induces a faster disease resolution compared with those patient who were on placebo. However, the use of caplacizumab was associated with increase bleeding tendencies in the studied subjects.
Most patients with refractory or relapsing TTP receive additional immunosuppressive therapy, e.g. vincristine, cyclophosphamide, splenectomy or a combination of the above.
Children with Upshaw-Schülman syndrome receive prophylactic plasma every two to three weeks; this maintains adequate levels of functioning ADAMTS13. Some tolerate longer intervals between plasma infusions. Additional plasma infusions may necessary for triggering events, such as surgery; alternatively, the platelet count may be monitored closely around these events with plasma being administered if the count drops.
Measurements of blood levels of lactate dehydrogenase, platelets, and schistocytes are used to monitor disease progression or remission. ADAMTS13 activity and inhibitor levels may be measured during follow-up, but in those without symptoms the use of rituximab is not recommended.
Early stage sepsis-associated purpura fulminans may be reversible with quick therapeutic intervention. Treatment is mainly removing the underlying cause and degree of clotting abnormalities and with supportive treatment (antibiotics, volume expansion, tissue oxygenation, etc.). Thus, treatment includes aggressive management of the septic state.
Purpura fulminans with disseminated intravascular coagulation should be urgently treated with fresh frozen plasma (10–20 mL/kg every 8–12 hours) and/or protein C concentrate to replace pro-coagulant and anticoagulant plasma proteins that have been depleted by the disseminated intravascular coagulation process.
Protein C in plasma in the steady state has a half life of 6- to 10-hour, therefore, patients with severe protein C deficiency and presenting with purpura fulminans can be treated acutely with an initial bolus of protein C concentrate 100 IU/kg followed by 50 IU /kg every 6 hours. A total of 1 IU/kg of protein C concentrate or 1 mL/kg of fresh frozen plasma will increase the plasma concentration of protein C by 1 IU/dL. Cases with comorbid pathological bleeding may require additional transfusions with platelet concentrate (10–15 mL/kg) or cryoprecipitate (5 mL/kg).
Established soft tissue necrosis may require surgical removal of the dead tissue, fasciotomy, amputation or reconstructive surgery.
Treatment of acquired dysfibrinogenemia follows the guidelines recommended for congenital dysfibrinogenemia. In addition, treatment of any disease thought to be responsible for the dysfibrinogenemia might be useful. For example, therapeutic plasma exchange and chemotherapy to reduce monoclonal antibody levels has been used successfully to reverse otherwise uncontrollable bleeding in cases of multiple myeloma-associated dysfibrinogenemia.
Anticoagulation, which prevents further coagulation, but does not act directly on existing clots, is the standard treatment for DVT. Balancing risk vs. benefit is important in determining the duration of anticoagulation, and three months is generally the standard length of treatment. In those with an annual risk of VTE in excess of 9%, as after an unprovoked episode, extended anticoagulation is a possibility. Those who finish VKA treatment after idiopathic VTE with an elevated D-dimer level show an increased risk of recurrent VTE (about 9% vs about 4% for normal results), and this result might be used in clinical decision-making. Thrombophilia test results rarely play a role in the length of treatment.
For acute cases in the leg, the ACCP recommended a parenteral anticoagulant (such as LMWH, fondaparinux, or unfractionated heparin) for at least five days and a VKA, the oral anticoagulant, the same day. LMWH and fondaparinux are suggested over unfractionated heparin, but both are retained in those with compromised kidney function, unlike unfractionated heparin. The VKA is generally taken for a minimum of three months to maintain an international normalized ratio of 2.0–3.0, with 2.5 as the target. The benefit of taking a VKA declines as the duration of treatment extends, and the risk of bleeding increases with age.
The ACCP recommended treatment for three months in those with proximal DVT provoked by surgery. A three-month course is also recommended for those with proximal DVT provoked by a transient risk factor, and three months is suggested over lengthened treatment when bleeding risk is low to moderate. Unprovoked DVT patients should have at least three months of anticoagulation and be considered for extended treatment. Those whose first VTE is an unprovoked proximal DVT are suggested for anticoagulation longer than three months unless there is a high risk of bleeding. In that case, three months is sufficient. Those with a second unprovoked VTE are recommended for extended treatment when bleeding risk is low, suggested for extended treatment when bleeding risk is moderate, and suggested for three months of anticoagulation in high-risk scenarios.
One area of treatment is managing people with major bleeding in a critical setting, like an emergency department. In these situations, the common treatment is transfusing a combination of red cells with one of the following options:
- Blood plasma
- Prothrombin complex concentrate, factor XIII, and fibrinogen
- Fibrinogen with tranexamic acid
The use of tranexamic acid is the only option that is currently supported by a large, randomized, controlled clinical trial, and is given to people with major bleeding after trauma. There are several possible risks to treating coagulopathies, such as transfusion-related acute lung injury, acute respiratory distress syndrome, multiple organ dysfunction syndrome, major hemorrhage, and venous thromboembolism.
Treatment of DIC is centered around treating the underlying condition. Transfusions of platelets or fresh frozen plasma can be considered in cases of significant bleeding, or those with a planned invasive procedure. The target goal of such transfusion depends on the clinical situation. Cryoprecipitate can be considered in those with a low fibrinogen level.
Treatment of thrombosis with anticoagulants such as heparin is rarely used due to the risk of bleeding.
Recombinant human activated protein C was previously recommended in those with severe sepsis and DIC, but drotrecogin alfa has been shown to confer no benefit and was withdrawn from the market in 2011.
Recombinant factor VII has been proposed as a "last resort" in those with severe hemorrhage due to obstetric or other causes, but conclusions about its use are still insufficient.
The first element of treatment is usually to discontinue the offending drug, although there have been reports describing how the eruption evolved little after it had established in spite of continuing the medication. Vitamin K1 can be used to reverse the effects of warfarin, and heparin or its low molecular weight heparin (LMWH) can be used in an attempt to prevent further clotting. None of these suggested therapies have been studied in clinical trials.
Heparin and LMWH act by a different mechanism than warfarin, so these drugs can also be used to prevent clotting during the first few days of warfarin therapy and thus prevent warfarin necrosis (this is called 'bridging').
Based on the assumption that low levels of protein C are involved in the underlying mechanism, common treatments in this setting include fresh frozen plasma or pure activated protein C.
Since the clot-promoting effects of starting administration of 4-hydroxycoumarins are transitory, patients with protein C deficiency or previous warfarin necrosis can still be restarted on these drugs if appropriate measures are taken. These include gradual increase starting from low doses and supplemental administration of protein C (pure or from fresh frozen plasma).
The necrotic skin areas are treated as in other conditions, sometimes healing spontaneously with or without scarring, sometimes going on to require surgical debridement or skin grafting.
For patients with vWD type 1 and vWD type 2A, desmopressin is available as different preparations, recommended for use in cases of minor trauma, or in preparation for dental or minor surgical procedures. Desmopressin stimulates the release of vWF from the Weibel-Palade bodies of endothelial cells, thereby increasing the levels of vWF (as well as coagulant factor VIII) three- to five-fold. Desmopressin is also available as a preparation for intranasal administration (Stimate) and as a preparation for intravenous administration. Recently, the FDA has approved the use of Baxalta’s Vonvendi. This is the first recombinant form of vWF. The effectiveness of this treatment is different than desmopressin because it only contains vWF, not vWF with the addition of FVIII. This treatment is only recommended for use by individuals who are 18 years of age or older.
Desmopressin is contraindicated in vWD type 2b because of the risk of aggravated thrombocytopenia and thrombotic complications. Desmopressin is probably not effective in vWD type 2M and is rarely effective in vWD type 2N. It is totally ineffective in vWD type 3.
For women with heavy menstrual bleeding, estrogen-containing oral contraceptive medications are effective in reducing the frequency and duration of the menstrual periods. Estrogen and progesterone compounds available for use in the correction of menorrhagia are ethinylestradiol and levonorgestrel (Levona, Nordette, Lutera, Trivora). Administration of ethinylestradiol diminishes the secretion of luteinizing hormone and follicle-stimulating hormone from the pituitary, leading to stabilization of the endometrial surface of the uterus.
Desmopressin is a synthetic analog of the natural antidiuretic hormone vasopressin. Its overuse can lead to water retention and dilutional hyponatremia with consequent convulsion.
For patients with vWD scheduled for surgery and cases of vWD disease complicated by clinically significant hemorrhage, human-derived medium purity factor VIII concentrates, which also contain von Willebrand factors, are available for prophylaxis and treatment. Humate P, Alphanate, Wilate and Koate HP are commercially available for prophylaxis and treatment of vWD. Monoclonally purified factor VIII concentrates and recombinant factor VIII concentrates contain insignificant quantity of vWF, so are not clinically useful.
Development of alloantibodies occurs in 10-15% of patients receiving human-derived medium-purity factor VIII concentrates and the risk of allergic reactions including anaphylaxis must be considered when administering these preparations. Administration of the latter is also associated with increased risk of venous thromboembolic complications.
Blood transfusions are given as needed to correct anemia and hypotension secondary to hypovolemia. Infusion of platelet concentrates is recommended for correction of hemorrhage associated with platelet-type vWD.
The antifibrinolytic agents epsilon amino caproic acid and tranexamic acid are useful adjuncts in the management of vWD complicated by clinical hemorrhage. The use topical thrombin JMI and topical Tisseel VH are effective adjuncts for correction of hemorrhage from wounds.
Arterial thrombosis is platelet-rich, and inhibition of platelet aggregation with antiplatelet drugs such as aspirin may reduce the risk of recurrence or progression.
Individuals with hypofibrinogenemia who have a history of excessive bleeding should be treated at a center specialized in treating hemophilia and avoid all medications that interfere with normal platelet function. During bleeding episodes, treatment with fibrinogen concentrates or, if unavailable infusion of fresh frozen plasma and/or cryoprecipitate (a fibrinogen-rich plasma fraction) to maintain fibrinogen activity levels >1 gram/liter.
Individuals with hypofibrinogenemia who experience episodic thrombosis should also be treated at a center specialized in treating hemophilia. Standard recommendations for these individuals are that they use antithrombotic agents and be instructed on antithrombotic behavioral methods in high risk situations (e.g. long car rides and air flights]]. Acute venous thrombosis episodes should be treated with low molecular weight heparin for a time that depends on personal and family history of thrombosis events. Prophylactic treatment prior to minor surgery should avoid fibrinogen supplementation and use anticoagulation measures; prior to major surgery, fibrinogen supplementation should be used only if serious bleeding occurs; otherwise, prophylactic anticoagulation measures are recommended.
Various studies have investigated the use of anticoagulation to suppress blood clot formation in cerebral venous sinus thrombosis. Before these trials had been conducted, there had been a concern that small areas of hemorrhage in the brain would bleed further as a result of treatment; the studies showed that this concern was unfounded. Clinical practice guidelines now recommend heparin or low molecular weight heparin in the initial treatment, followed by warfarin, provided there are no other bleeding risks that would make these treatments unsuitable. Some experts discourage the use of anticoagulation if there is extensive hemorrhage; in that case, they recommend repeating the imaging after 7–10 days. If the hemorrhage has decreased in size, anticoagulants are started, while no anticoagulants are given if there is no reduction.
The duration of warfarin treatment depends on the circumstances and underlying causes of the condition. If the thrombosis developed under temporary circumstances (e.g. pregnancy), three months are regarded as sufficient. If the condition was unprovoked but there are no clear causes or a "mild" form of thrombophilia, 6 to 12 months is advised. If there is a severe underlying thrombosis disorder, warfarin treatment may need to continue indefinitely.
Thrombolysis (removal of the blood clot with "clot buster" medication) has been described, either systemically by injection into a vein or directly into the clot during angiography. The 2006 European Federation of Neurological Societies guideline recommends that thrombolysis is only used in patients who deteriorate despite adequate treatment, and other causes of deterioration have been eliminated. It is unclear which drug and which mode of administration is the most effective. Bleeding into the brain and in other sites of the body is a major concern in the use of thrombolysis. American guidelines make no recommendation with regards to thrombolysis, stating that more research is needed.
Raised intracranial pressure, if severe or threatening vision, may require therapeutic lumbar puncture (removal of excessive cerebrospinal fluid), medication (acetazolamide), or neurosurgical treatment (optic nerve sheath fenestration or shunting). In certain situations, anticonvulsants may be used to try to prevent seizures. These situations include focal neurological problems (e.g. inability to move a limb) and focal changes of the brain tissue on CT or MRI scan. Evidence to support or refute the use of antiepileptic drugs as a preventive measure, however, is lacking.
Patient with KMS can be extremely ill and may need intensive care. They are at risk of bleeding complications including intracranial hemorrhage. The thrombocytopenia and coagulopathy are managed with platelet transfusions and fresh frozen plasma, although caution is needed due to the risk of fluid overload and heart failure from multiple transfusions. The possibility of disseminated intravascular coagulation, a dangerous and difficult-to-manage condition, is concerning. Anticoagulant and antiplatelet medications can be used after careful assessment of the risks and benefits.
There are too few cases of fibrinogen storage disease to establish optimal treatments for the liver diseases. Management of the disorder has been based on general recommendations for patients with liver disease, particularly Alpha 1 antitrypsin deficiency-associated liver disease. In the latter disease, autophagy, the pathway that cells use to dispose of dysfunctional or excessively stored components including proteins, has been targeted using autophagy-enhancing drugs, e.g. carbamazepine, vitamin E, and ursodeoxycholic acid. These drugs have been tested in individual patients with fibrin storage disease with some success in reducing evidence of liver injure, i.e. reduction in blood liver enzyme levels. These and other autophagy-enhancing drugs are suggested to be further studied in fibrinogen storage disease.
Splenic infarction can be induced for the treatment of such conditions as portal hypertension or splenic injury. It can also be used prior to splenectomy for the prevention of blood loss.
Generally, treatment of the underlying vascular tumor results in resolution of KMS. If complete surgical resection is feasible, it provides a good opportunity for cure (although it can be dangerous to operate on a vascular tumor in a patient prone to bleeding, even with appropriate surgical subspecialists involved).
If surgery is not possible, various other techniques can be used to control the tumor: