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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.
In people without a detectable thrombophilia, the cumulative risk of developing thrombosis by the age of 60 is about 12%. About 60% of people who are deficient in antithrombin will have experienced thrombosis at least once by age 60, as will about 50% of people with protein C deficiency and about a third of those with protein S deficiency. People with activated protein C resistance (usually resulting from factor V Leiden), in contrast, have a slightly raised absolute risk of thrombosis, with 15% having had at least one thrombotic event by the age of sixty. In general, men are more likely than women to experience repeated episodes of venous thrombosis.
People with factor V Leiden are at a relatively low risk of thrombosis, but may develop thrombosis in the presence of an additional risk factor, such as immobilization. Most people with the prothrombin mutation (G20210A) never develop thrombosis.
Evidence-based clinical guidelines were published in 2016 for the treatment of VTE.
Evidence supports the use of heparin in people following surgery who have a high risk of thrombosis to reduce the risk of DVTs; however, the effect on PEs or overall mortality is not known. In hospitalized non-surgical patients, mortality decreased but not statistically significant. It does not appear however to decrease the rate of symptomatic DVTs. Using both heparin and compression stockings appears better than either one alone in reducing the rate of DVT.
In hospitalized people who have had a stroke and not had surgery, mechanical measures (compression stockings) resulted in skin damage and no clinical improvement. Data on the effectiveness of compression stockings among hospitalized non-surgical patients without stroke is scarce.
The American College of Physicians (ACP) gave three strong recommendations with moderate quality evidence on VTE prevention in non-surgical patients: that hospitalized patients be assessed for their risk of thromboembolism and bleeding before prophylaxis (prevention); that heparin or a related drug is used if potential benefits are thought to outweigh potential harms; and that graduated compression stockings not be used. As an ACP policy implication, the guideline stated a lack of support for any performance measures that incentivize physicians to apply universal prophylaxis without regard to the risks. Goldhaber recommends that people should be assessed at their hospital discharge for persistent high-risk of venous thrombosis, and that people who adopt a heart-healthy lifestyle might lower their risk of venous thrombosis.
In those with cancer who are still walking about yet receiving chemotherapy, LMWH decreases the risk of VTE. Due to potential concerns of bleeding its routine use is not recommended. For people who are having surgery for cancer, it is recommended that they receive anticoagulation therapy (preferably LMWH) in order to prevent a VTE. LMWH is recommended for at least 7–10 days following cancer surgery, and for one month following surgery for people who have a high risk of VTEs.
In adults who have had their lower leg casted or placed in a brace for more than a week, LMWH decreased the risk of VTEs. LMWH is recommended for adults not in hospital with an above-knee cast and a below-knee cast, and is safe for this indication.
Following the completion of warfarin in those with prior VTE, long term aspirin is beneficial.
Unfractionated heparin, low molecular weight heparin, warfarin (not to be used during pregnancy) and aspirin remain the basis of antithrombotic treatment and prophylaxis both before and during pregnancy.
While the consensus among physicians is the safety of the mother supersedes the safety of the developing fetus, changes in the anticoagulation regimen during pregnancy can be performed to minimize the risks to the developing fetus while maintaining therapeutic levels of anticoagulants in the mother.
The main issue with anticoagulation in pregnancy is that warfarin, the most commonly used anticoagulant in chronic administration, is known to have teratogenic effects on the fetus if administered in early pregnancy. Still, there seems to be no teratogenic effect of warfarin before six weeks of gestation. However, unfractionated heparin and low molecular weight heparin do not cross the placenta.
It is known that diabetes causes changes to factors associated with coagulation and clotting, however not much is known of the risk of thromboembolism, or clots, in diabetic patients. There are some studies that show that diabetes increases the risk of thromboembolism; other studies show that diabetes does not increase the risk of thromboembolism. A study conducted in the Umea University Hospital, in Sweden, observed patients that were hospitalized due to an thromboembolism from 1997 to 1999. The researchers had access to patient information including age, sex, vein thromboembolism diagnosis, diagnostic methods, diabetes type and medical history. This study concluded that there is, in fact, an increased risk of thromboembolism development in diabetic patients, possibly due to factors associated with diabetes or diabetes itself. Diabetic patients are twice as likely to develop a thromboembolism than are non-diabetic patient. The exact mechanism of how diabetes increases the risk of clot formation remains unclear and could possibly be a future direction for study.
From previous studies, it is known that long distance air travel is associated with high risk of venous thrombosis. Long periods of inactivity in a limited amount of space may be a reason for the increased risk of blood clot formation. In addition, bent knees compresses the vein behind the knee (the popliteal vein) and the low humidity, low oxygen, high cabin pressure and consumption of alcohol concentrate the blood. A recent study, published in the British Journal of Haematology in 2014, determined which groups of people, are most at risk for developing a clot during or after a long flight. The study focused on 8755 frequent flying employees from international companies and organizations. It found that travelers who have recently undergone a surgical procedure or who have a malignant disease such as cancer or who are pregnant are most at risk. Preventative measures before flying may be taken in these at-risk groups as a solution.
Patients who have undergone kidney transplant have a high risk of developing RVT (about 0.4% to 6%). RVT is known to account for a large proportion of transplanted kidney failures due to technical problems (damage to the renal vein), clotting disorders, diabetes, consumption of ciclosporin or an unknown problem. Patients who have undergone a kidney transplant are commonly prescribed ciclosporin, an immunosuppressant drug which is known to reduce renal blood flow, increase platelet aggregation in the blood and cause damage to the endothelial tissue of the veins. In a clinical study conducted by the Nuffield Department of Surgery at the Oxford Transplant Centre, UK, transplant patients were given low doses of aspirin, which has a some anti-platelet activity. There is risk of bleeding in transplant patients when using anticoagulants like warfarin and herapin. Low dosage of aspirin was used as an alternative. The study concluded that a routine low-dose of aspirin in kidney transplant patients who are also taking ciclosporin significantly reduces the risk of RVT development.
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.
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.
Warfarin resistance is a rare condition in which people have varying degrees of tolerance to the anticoagulant drug warfarin. In incomplete warfarin resistance, people only respond to high doses of warfarin; in complete warfarin resistance, the drug has no effect. This can be because the drug is metabolized quickly or because the clotting cascade does not interact with warfarin as it should. One gene that has been identified in warfarin resistance is VKORC1, a gene responsible for warfarin metabolism. It is inherited in an autosomal dominant pattern.
A consensus on the correct anticoagulation regimen during pregnancy is lacking. Treatment is tailored to the particular individual based on her risk of complications. Warfarin and other vitamin K-inhibiting agents are contraindicated during the first trimester of pregnancy because of the teratogenic effects, and should not be administered when the pregnancy is confirmed. Rather, women who are on chronic anticoagulation may be given the option of conversion to either unfractionated heparin or low molecular weight heparin (LMWH), such as tinzaparin, prior to a planned conception. LMWH is as safe and efficacious as unfractionated heparin. A blood test including platelets and a clotting screen should be performed prior to administration of anticoagulant regimens in pregnancy.
Subcutaneous tinzaparin may be given at doses of 175 units of antifactor Xa activity per kg, based on prepregnancy or booking weight at approximately 16 weeks, and not the current weight. While unfractionated heparin is otherwise typically given in an intravenous formulation, this is inconvenient for the prolonged period of administration required in pregnancy.
Whether warfarin can be reinitiated after the 12th week of pregnancy is unclear. In a recent retrospective analysis, resumption of warfarin after the first trimester is completed is associated with increased risk of loss of the fetus. However, this analysis included only individuals who were treated with anticoagulants for mechanical heart valves, who generally require high levels of anticoagulation.
In pregnant women with mechanical heart valves, the optimal anticoagulation regimen is particularly unclear. Anticoagulation with subcutaneous heparin in this setting is associated with a high incidence of thrombosis of the valve and death. Similar issues are likely associated with the use of enoxaparin (a LMWH) in these high-risk individuals.
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.
Given the fact that HIT predisposes strongly to new episodes of thrombosis, it is not sufficient to simply discontinue the heparin administration. Generally, an alternative anticoagulant is needed to suppress the thrombotic tendency while the generation of antibodies stops and the platelet count recovers. To make matters more complicated, the other most commonly used anticoagulant, warfarin, should not be used in HIT until the platelet count is at least 150 x 10^9/L because there is a very high risk of warfarin necrosis in people with HIT who have low platelet counts. Warfarin necrosis is the development of skin gangrene in those receiving warfarin or a similar vitamin K inhibitor. If the patient was receiving warfarin at the time when HIT is diagnosed, the activity of warfarin is reversed with vitamin K. Transfusing platelets is discouraged, as there is a theoretical risk that this may worsen the risk of thrombosis; the platelet count is rarely low enough to be the principal cause of significant hemorrhage.
Various non-heparin agents are used to provide anticoagulation in those with strongly suspected or proven HIT: danaparoid, fondaparinux, bivalirudin and argatroban. These are alternatives to heparin therapy. Not all agents are available in all countries, and not all are approved for this specific use. For instance, argatroban is only recently licensed in the United Kingdom, and danaparoid is not available in the United States. Fondaparinux, a Factor Xa inhibitor, is commonly used off label for HIT treatment in the United States.
According to a systematic review, people with HIT treated with lepirudin showed a relative risk reduction of clinical outcome (death, amputation, etc.) to be 0.52 and 0.42 when compared to patient controls. In addition, people treated with argatroban for HIT showed a relative risk reduction of the above clinical outcomes to be 0.20 and 0.18. Lepirudin production stopped on May 31, 2012.
Surgery to remove the clot is possible, but rarely performed. In the past, surgical removal of the renal vein clot was the primary treatment but it is very invasive and many complications can occur. In the past decades, treatment has shifted its focus from surgical intervention to medical treatments that include intravenous and oral anticoagulants. The use of anticoagulants may improve renal function in RVT cases by removing the clot in the vein and preventing further clots from occurring. Patients already suffering from nephrotic syndrome may not need to take anticoagulants. In this case, patients should keep an eye out and maintain reduced level of proteinuria by reducing salt and excess protein, and intaking diuretics and statins. Depending on the severity of RVT, patients may be on anticoagulants from a year up to a lifetime. As long as the albumen levels in the bloodstream are below 2.5g/L, it is recommended that RVT patients continue taking anticoagulants. Main anticoagulants that can be used to treat RVT include warfarin and low molecular weight heparin. Heparin has become very popular, because of its low risk of complications, its availability and because it can easily be administered. Warfarin is known to interact with many other drugs, so careful monitoring is required. If a nephrotic syndrome patient experiences any of the RVT symptoms (flank or back pain, blood in the urine or decreased renal function), he or she should immediately see a doctor to avoid further complications.
The main side effect of anticoagulants is the risk of excessive bleeding. Other side effects include: blood in the urine or feces, severe bruising, prolonged nosebleeds (lasting longer than 10 minutes), bleeding gum, blood in your vomit or coughing up blood, unusual headaches, sudden severe back pain, difficulty breathing or chest pain, in women, heavy or increased bleeding during the period, or any other bleeding from the vagina. Warfarin can cause rashes, diarrhea, nausea (feeling sick) or vomiting, and hair loss. Heparin can cause hair loss (alopecia) thrombocytopenia – a sudden drop in the number of platelets in the blood.
It has been reported in a case study of 27 patients with nephrotic syndrome caused RVT, there was a 40% mortality rate, mostly due to hemorrhagic complications and sepsis. In 75% of the remaining surviving patients, the RVT was resolved and renal function returned to normal. It has been concluded that age is not a factor on the survival of RVT patients, although older patient (55 and older) are more likely to develop renal failure. Heparin is crucial in returning normal renal function; in patients that did not take heparin, long term renal damage was observed in 100%. In patients that did take heparin, renal damage was observed in about 33%. By quickly treating, and receiving the correct medications, patients should increase their chances of survival and reduce the risk of the renal vein clot from migrating to another part of the body.
Heparin enhances ATIII activity and neutralizes "activated serine protease coagulation factors." Patients with ATIII deficiency requiring anticoagulant therapy with heparin will need higher doses of heparin. ATIII binds to thrombin and then forms the thrombin-anti thrombin complex or TAT complex. This is a major natural pathway of anticoagulation. This binding of thrombin to AT is greatly enhanced in the presence of heparin. Heparin does not affect vitamin K metabolism, so giving vitamin K1 (Phytonadione) will not reverse the effects of heparin.
Heparin is used as "bridging" therapy when initiating a patient on warfarin in a hospital setting. It can be used in DVT prophylaxis and treatment, acute coronary syndromes, and ST-segment elevated MI.
An estimated 64 percent of patients with venous thromboembolism may have activated protein C resistance.
Many conditions mimic or may be mistaken for warfarin necrosis, including pyoderma gangrenosum or necrotizing fasciitis. Warfarin necrosis is also different from another drug eruption associated with warfarin, purple toe syndrome, which usually occurs three to eight weeks after the start of anticoagulation therapy. No report has described this disorder in the immediate postpartum period in patients with protein S deficiency.
The exact number of cases of HIT in the general population is unknown. What is known is that women receiving heparin after a recent surgical procedure, particularly cardiothoracic surgery, have a higher risk, while the risk is very low in women just before and after giving birth. Some studies have shown that HIT is less common in those receiving low molecular weight heparin.
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.
The amount of fresh frozen plasma required to reverse disseminated intravascular coagulation associated with purpura fulminans may lead to complications of fluid overload and death, especially in neonates, such as transfusion-related acute lung injury. Exposure to multiple plasma donors over time increases the cumulative risk for transfusion-associated viral infection and allergic reaction to donor proteins found in fresh frozen plasma.
Allergic reactions and alloantibody formation are also potential complications, as with any protein replacement therapy.
Concomitant warfarin therapy in subjects with congenital protein C deficiency is associated with an increased risk of warfarin skin necrosis.
Treatment is almost always aimed to control hemorrhages, treating underlying causes, and taking preventative steps before performing invasive surgeries.
Hypoprothrombinemia can be treated with periodic infusions of purified prothrombin complexes. These are typically used as treatment methods for severe bleeding cases in order to boost clotting ability and increasing levels of vitamin K-dependent coagulation factors.
1. A known treatment for hypoprothrombinemia is menadoxime.
2. Menatetrenone was also listed as a Antihaemorrhagic vitamin.
3. 4-Amino-2-methyl-1-naphthol (Vitamin K5) is another treatment for hypoprothrombinemia.
1. Vitamin K forms are administered orally or intravenously.
4. Other concentrates include Proplex T, Konyne 80, and Bebulin VH.
Fresh Frozen Plasma infusion (FFP) is a method used for continuous bleeding episodes, every 3-5 weeks for mention.
1. Used to treat various conditions related to low blood clotting factors.
2. Administered by intravenous injection and typically at a 15-20 ml/kg/dose.
3. Can be used to treat acute bleeding.
Sometimes, underlying causes cannot be controlled or determined, so management of symptoms and bleeding conditions should be priority in treatment.
Invasive options, such as surgery or clotting factor infusions, are required if previous methods do not suffice. Surgery is to be avoided, as it causes significant bleeding in patients with hypoprothrombinemia.
Prognosis for patients varies and is dependent on severity of the condition and how early the treatment is managed.
1. With proper treatment and care, most people go on to live a normal and healthy life.
2. With more severe cases, a hematologist will need to be seen throughout the patient's life in order to deal with bleeding and continued risks.
Activated protein C (with protein S as a cofactor) degrades Factor Va and Factor VIIIa. Activated protein C resistance is the inability of protein C to cleave Factor Va and/or Factor VIIIa, which allows for longer duration of thrombin generation and may lead to a hypercoagulable state. This may be hereditary or acquired. The best known and most common hereditary form is Factor V Leiden. Acquired forms occur in the presence of elevated Factor VIII concentrations.
Following are some complications of coagulopathies, some of them caused by their treatments:
In terms of treatment for protein S deficiency the following are consistent with the "management" (and administration of) individuals with this condition ( it should be noted that the prognosis for "inherited" homozygotes is usually in line with a higher incidence of thrombosis for the affected individual):
The long-term prognosis for APS is determined mainly by recurrent thrombosis, which may occur in up to 29% of patients, sometimes despite antithrombotic therapy.
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.