Made by DATEXIS (Data Science and Text-based Information Systems) at Beuth University of Applied Sciences Berlin
Deep Learning Technology: Sebastian Arnold, Betty van Aken, Paul Grundmann, Felix A. Gers and Alexander Löser. Learning Contextualized Document Representations for Healthcare Answer Retrieval. The Web Conference 2020 (WWW'20)
Funded by The Federal Ministry for Economic Affairs and Energy; Grant: 01MD19013D, Smart-MD Project, Digital Technologies
Initial treatment usually consists of the administration of corticosteroids, a group of medications that suppress the immune system. The dose and mode of administration is determined by platelet count and whether there is active bleeding: in urgent situations, infusions of dexamethasone or methylprednisolone may be used, while oral prednisone or prednisolone may suffice in less severe cases. Once the platelet count has improved, the dose of steroid is gradually reduced while the possibility of relapse is monitored. 60–90 percent will experience a relapse during dose reduction or cessation. Long-term steroids are avoided if possible because of potential side-effects that include osteoporosis, diabetes and cataracts.
There is increasing use of immunosuppressants such as mycophenolate mofetil and azathioprine because of their effectiveness. In chronic refractory cases, where immune pathogenesis has been confirmed, the off-label use of the "vinca" alkaloid and chemotherapy agent vincristine may be attempted. However, vincristine has significant side effects and its use in treating ITP must be approached with caution, especially in children.
Discontinuation of heparin is critical in a case of heparin-induced thrombocytopenia (HIT). Beyond that, however, clinicians generally treat to avoid a thrombosis, often by starting patients directly on warfarin. For this reason, patients are usually treated with a direct thrombin inhibitor, such as lepirudin or argatroban, which are approved by the FDA for this use. Other blood thinners sometimes used in this setting that are not FDA-approved for treatment of HIT include bivalirudin and fondaparinux. Platelet transfusions are not routinely used to treat HIT because thrombosis, not bleeding, is the primary problem.
Treatment is guided by the severity and specific cause of the disease. Treatment focuses on eliminating the underlying problem, whether that means discontinuing drugs suspected to cause it or treating underlying sepsis. Diagnosis and treatment of serious thrombocytopenia is usually directed by a hematologist. Corticosteroids may be used to increase platelet production. Lithium carbonate or folate may also be used to stimulate platelet production in the bone marrow.
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.
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
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.
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.
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.
Desmopressin (DDAVP) may be used in those with mild haemophilia A. Tranexamic acid or epsilon aminocaproic acid may be given along with clotting factors to prevent breakdown of clots.
Pain medicines, steroids, and physical therapy may be used to reduce pain and swelling in an affected joint.
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.
While there is no cure for haemophilia, treatment improves outcomes.
Treatment is directed at the prevention of haemorrhagic shock. Standard dose prednisolone does not increase the platelet count. High-dose methylprednisolone therapy in children with Onyalai has been shown to improve platelet count and reduce the requirement for transfusions. Vincristine sulphate may be of benefit to some patients. Splenectomy is indicated in patients with severe uncontrollable haemorrhage. High-dose intravenous gammaglobulin may help in increasing the platelet count and cessation of haemorrhage.
The mortality rate is around 95% for untreated cases, but the prognosis is reasonably favorable (80–90% survival) for patients with idiopathic TTP diagnosed and treated early with plasmapheresis.
Cordocentesis can be performed in utero to determine the platelet count of the fetus. This procedure is only performed if a "prior" pregnancy was affected by . Intrauterine transfusions can be performed during cordocentesis for primary prevention of intracerebral hemorrhage. Any administered cellular blood products must be irradiated to reduce the risk of graft-versus-host disease in the fetus. Additionally, all administered blood products should be reduced-risk ( seronegative and leukoreduced are considered essentially equivalent for the purposes of risk reduction).
If intrauterine platelet transfusions are performed, they are generally repeated weekly (platelet lifespan after transfusion is approximately 8 to 10 days). Platelets administered to the fetus must be negative for the culprit antigen (often -1a, as stated above). Many blood suppliers (such as American Red Cross and United Blood Services) have identified -1a negative donors. An alternative donor is the mother who is, of course, negative for the culprit antigen. However, she must meet general criteria for donation and platelets received from the mother must be washed to remove the offending alloantibody and irradiated to reduce the risk of graft-versus-host disease. If platlet transfusions are needed urgently, incompatible platelets may be used, with the understanding that they may be less effective and that the administration of any blood product carries risk.
The use of Intravenous immunoglobulin () during pregnancy and immediately after birth has been shown to help reduce or alleviate the effects of in infants and reduce the severity of thrombocytopenia. The most common treatment is weekly infusions at a dosage of 1 g/kg beginning at 16 to 28 weeks of pregnancy, depending on the severity of the disease in the previous affected child, and continuing until the birth of the child. In some cases this dosage is increased to 2 g/kg and/or combined with a course of prednisone depending on the exact circumstances of the case. Although this treatment has not been shown to be effective in all cases it has been shown to reduce the severity of thrombocytopenia in some. Also, it is suspected that (though not understood why) provides some added protection from intercranial haemorrhage () to the fetus. Even with treatment, the fetal platelet count may need to be monitored and platelet transfusions may still be required.
The goal of both and platelet transfusion is to avoid hemorrhage. Ultrasound monitoring to detect hemorrhage is not recommended as detection of intracranial hemorrhage generally indicates permanent brain damage (there is no intervention that can be performed to reverse the damage once it has occurred).
Before delivery, the fetal platelet count should be determined. A count of >50,000 μL is recommended for vaginal delivery and the count should be kept above 20,000 μL after birth.
There has been no general recommendation for treatment of patients with Giant Platelet Disorders, as there are many different specific classifications to further categorize this disorder which each need differing treatments. Platelet transfusion is the main treatment for people presenting with bleeding symptoms. There have been experiments with DDAVP (1-deamino-8-arginine vasopressin) and splenectomy on people with Giant platelet disorders with mixed results, making this type of treatment contentious.
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.
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.
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.
Management of KMS, particularly in severe cases, can be complex and require the joint effort of multiple subspecialists. This is a rare disease with no consensus treatment guidelines or large randomized controlled trials to guide therapy.
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.
Individuals experiencing episodic bleeding as a result of congenital dysfibrinogenemia should be treated at a center specialized in treating hemophilia. They should avoid all medications that interfere with normal platelet function. During bleeding episodes, treatment with fibrinogen concentrates or in emergencies or when these concentrates are unavailable, infusions of fresh frozen plasma and/or cryoprecipitate (a fibrinogen-rich plasma fraction) to maintain fibrinogen activity levels >1 gram/liter. Tranexamic acid or fibrinogen concentrates are recommended for prophylactic treatment prior to minor surgery while fibrinogen concentrates are recommended prior to major surgery with fibrinogen concentrates usage seeking to maintain fibrinogen activity levels at >1 gram/liter. Women undergoing vaginal or Cesarean child birth should be treated at a hemophilia center with fibrinogen concentrates to maintain fibrinogen activity levels at 1.5 gram/liter. The latter individuals require careful observation for bleeding during their post-partum periods.
Individuals experiencing episodic thrombosis as a result of congenital dysfibrinogenemia should also be treated at a center specialized in treating hemophilia using antithrombotic agents. They should be instructed on antithrombotic behavioral methods fur use in high risk situations such as long car rides and air flights. Venous thrombosis should be treated with low molecular weight heparin for a period that depends on personal and family history of thrombosis events. Prophylactic treatment prior to minor surgery should avoid fibrinogen supplementation and use prophylactic anticoagulation measures; prior to major surgery, fibrinogen supplementation should be used only if serious bleeding occurs; otherwise, prophylactic anticoagulation measures are recommended.
The therapy of an acute TTP episode has to be started as early as possible. The standard treatment is the daily replacement of the missing ADAMTS13 protease in form of plasma infusions or in more severe episodes by plasma exchange. In the latter the patients plasma is replaced by donated plasma. The most common sources of ADAMTS13 is platelet-poor fresh frozen plasma (FFP) or solvent-detergent plasma.
The benefit of plasma exchange compared to plasma infusions alone may result from the additional removal of ULVWF. In general both plasma therapies are well tolerated, several mostly minor complications may be observed. The number of infusion/exchange sessions needed to overcome a TTP episode are variable but usually take less than a week in USS. The intensive plasma-therapy is generally stopped when platelet count increases to normal levels and is stable over several days.
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.
In terms of treatment/management, bleeding events can be controlled by platelet transfusion.
Most heterozygotes, with few exceptions, do not have a bleeding diathesis. BSS presents as a bleeding disorder due to the inability of platelets to bind and aggregate at sites of vascular endothelial injury. In the event of an individual with mucosal bleeding tranexamic acid can be given.
The affected individual may need to avoid contact sports and medications such as aspirin, which can increase the possibility of bleeding. A potential complication is the possibility of the individual producing antiplatelet antibodies