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Treatment of asymptomatic congenital dysfibrinogenemia depends in part on the expectations of developing bleeding and/or thrombotic complications as estimated based on the history of family members with the disorder and, where available, determination of the exact mutation causing the disorder plus the propensity of the particular mutation type to develop these complications. In general, individuals with this disorder require regular follow-up and multidiscipline management prior to surgery, pregnancy, and giving childbirth. Women with the disorder appear to have an increased rate of miscarriages and all individuals with fibrinogen activity in clotting tests below 0.5 grams/liter are prone to bleeding and spontaneous abortions. Women with multiple miscarriages and individuals with excessively low fibrinogen activity levels should be considered for prophylaxis therapy with fibrinogen replacement during pregnancy, delivery, and/or surgery.
Diagnosis of acquired dysfibrinogenemia uses the same laboratory tests that are used for congenital dysfibrinogenemia plus evidence for an underlying causative disease.
Genetic testing and counselling are available to help determine the risk of passing the condition onto a child. This may involve testing a sample of tissue or blood to look for signs of the genetic mutation that causes haemophilia.
A pregnant woman with a history of haemophilia in her family can test for the haemophilia gene. Such tests include:
- chorionic villus sampling (CVS) – a small sample of the placenta is removed from the womb and tested for the haemophilia gene, usually during weeks 11-14 of pregnancy
- amniocentesis – a sample of amniotic fluid is taken for testing, usually during weeks 15-20 of pregnancy
There's a small risk of these procedures causing problems such as miscarriage or premature labour, so the woman may discuss this with the doctor in charge of her care.
When vWD is suspected, blood plasma of a patient must be investigated for quantitative and qualitative deficiencies of vWF. This is achieved by measuring the amount of vWF in a vWF antigen assay and the functionality of vWF with a glycoprotein (GP)Ib binding assay, a collagen binding assay, or a ristocetin cofactor activity (RiCof) or ristocetin induced platelet agglutination (RIPA) assays. Factor VIII levels are also performed because factor VIII is bound to vWF which protects the factor VIII from rapid breakdown within the blood. Deficiency of vWF can then lead to a reduction in factor VIII levels, which explains the elevation in PTT. Normal levels do not exclude all forms of vWD, particularly type 2, which may only be revealed by investigating platelet interaction with subendothelium under flow, a highly specialized coagulation study not routinely performed in most medical laboratories. A platelet aggregation assay will show an abnormal response to ristocetin with normal responses to the other agonists used. A platelet function assay may give an abnormal collagen/epinephrine closure time, and in most cases, a normal collagen/ADP time. Type 2N may be considered if factor VIII levels are disproportionately low, but confirmation requires a "factor VIII binding" assay. Additional laboratory tests that help classify sub-types of vWD include von-willebrand multimer analysis, modified ristocetin induced platelet aggregation assay and vWF propeptide to vWF antigen ratio propeptide. In cases of suspected acquired von-Willebrand syndrome, a mixing study study (analysis of patient plasma along with pooled normal plasma/PNP and a mixture of the two tested immediately, at one hour, and at two hours) should be performed. Detection of vWD is complicated by vWF being an acute phase reactant with levels rising in infection, pregnancy, and stress.
Other tests performed in any patient with bleeding problems are a complete blood count-CBC (especially platelet counts), activated partial thromboplastin time-APTT, prothrombin time with International Normalized Ratio-PTINR, thrombin time-TT, and fibrinogen level. Testing for factor IX may also be performed if hemophilia B is suspected. Other coagulation factor assays may be performed depending on the results of a coagulation screen. Patients with von Willebrand disease typically display a normal prothrombin time and a variable prolongation of partial thromboplastin time.
The testing for vWD can be influenced by laboratory procedures. Numerous variables exist in the testing procedure that may affect the validity of the test results and may result in a missed or erroneous diagnosis. The chance of procedural errors are typically greatest during the preanalytical phase (during collecting storage and transportation of the specimen) especially when the testing is contracted to an outside facility and the specimen is frozen and transported long distances. Diagnostic errors are not uncommon, and the rate of testing proficiency varies amongst laboratories, with error rates ranging from 7 to 22% in some studies to as high as 60% in cases of misclassification of vWD subtype. To increase the probability of a proper diagnosis, testing should be done at a facility with immediate on-site processing in a specialized coagulation laboratory.
The diagnosis of hypofibrinogenemia is indicated in individuals who have low levels (<1.5 gram/liter) of plasma fibrinogen as determined by both immunological (e.g. immunoelectrophoresis and (i.e. able to be clotted) methods. The ratio of immunological to functional fibrinogen masses should be ~1.0 as assayed with partial thromboplastin time, activated partial thromboplastin time, thrombin time, and reptilase time tests. These tests are used to distinguish hypofibrinogenemia from hypodysfibrinogenemia, a typically more severe disorder in which plasma fibrinogen levels are low and this fibrinogen includes at least in part dysfunctional fibrinogen. Immunological/functional fibrinogen ratios for the plasma of individuals with hypodysfibrinogenemia for all the cited tests are usually <0.7. Where available, further analyses are recommended; these include analyses of the fibrinogen genes and protein chains for mutations and specialized studies of individuals in vitro induced blood clots for stability and susceptibility to lyses.
The diagnosis of fibrin storage disease requires liver biopsy and the finding of immunologically detectable fibrinogen inclusion bodies in hepatocytes.
Blood tests are neede to differentiate FVII deficiency from other bleeding disorders. Typical is a discordance between the prolonged prothrombin time (PT) and normal levels for the activated partial thromboplastin time (APTT). FVII levels are <10IU/dl in homozygous individuals, and between 20-60 in heterozygous carriers. The FCVII: C assay supports the diagnosis.
The FVII gene (F7) is found on chromosome 13q34. Heterogeneous mutations have been described in FVII deficient patients.
The condition is diagnosed by blood tests in the laboratory when it is noted that special blood clotting test are abnormal. Specifically prothrombin time (PT) or activated partial thromboplastin time(aPTT) are prolonged. The diagnosis is confirmed by an assay detecting very low or absent FXII levels.
The FXII (F12) gene is found on chromosome 5q33-qter.
In hereditary angioedema type III an increased activity of factor XII has been described.
There are divergent views as to whether everyone with an unprovoked episode of thrombosis should be investigated for thrombophilia. Even those with a form of thrombophilia may not necessarily be at risk of further thrombosis, while recurrent thrombosis is more likely in those who have had previous thrombosis even in those who have no detectable thrombophilic abnormalities. Recurrent thromboembolism, or thrombosis in unusual sites (e.g. the hepatic vein in Budd-Chiari syndrome), is a generally accepted indication for screening. It is more likely to be cost-effective in people with a strong personal or family history of thrombosis. In contrast, the combination of thrombophilia with other risk factors may provide an indication for preventative treatment, which is why thrombophilia testing may be performed even in those who would not meet the strict criteria for these tests. Searching for a coagulation abnormality is not normally undertaken in patients in whom thrombosis has an obvious trigger. For example, if the thrombosis is due to immobilization after recent orthopedic surgery, it is regarded as "provoked" by the immobilization and the surgery and it is less likely that investigations will yield clinically important results.
When venous thromboembolism occurs when a patient is experiencing transient major risk factors such as prolonged immobility, surgery, or trauma, testing for thrombophilia is not appropriate because the outcome of the test would not change a patient's indicated treatment. In 2013, the American Society of Hematology, as part of recommendations in the Choosing Wisely campaign, cautioned against overuse of thrombophilia screening; false positive results of testing would lead to people inappropriately being labeled as having thrombophilia, and being treated with anticoagulants without clinical need
In the United Kingdom, professional guidelines give specific indications for thrombophilia testing. It is recommended that testing be done only after appropriate counseling, and hence the investigations are usually not performed at the time when thrombosis is diagnosed but at a later time. In particular situations, such as retinal vein thrombosis, testing is discouraged altogether because thrombophilia is not regarded as a major risk factor. In other rare conditions generally linked with hypercoagulability, such as cerebral venous thrombosis and portal vein thrombosis, there is insufficient data to state for certain whether thrombophilia screening is helpful, and decisions on thrombophilia screening in these conditions are therefore not regarded as evidence-based. If cost-effectiveness (quality-adjusted life years in return for expenditure) is taken as a guide, it is generally unclear whether thrombophilia investigations justify the often high cost, unless the testing is restricted to selected situations.
Recurrent miscarriage is an indication for thrombophilia screening, particularly antiphospholipid antibodies (anti-cardiolipin IgG and IgM, as well as lupus anticoagulant), factor V Leiden and prothrombin mutation, activated protein C resistance and a general assessment of coagulation through an investigation known as thromboelastography.
Women who are planning to use oral contraceptives do not benefit from routine screening for thrombophilias, as the absolute risk of thrombotic events is low. If either the woman or a first-degree relative has suffered from thrombosis, the risk of developing thrombosis is increased. Screening this selected group may be beneficial, but even when negative may still indicate residual risk. Professional guidelines therefore suggest that alternative forms of contraception be used rather than relying on screening.
Thrombophilia screening in people with arterial thrombosis is generally regarded unrewarding and is generally discouraged, except possibly for unusually young patients (especially when precipitated by smoking or use of estrogen-containing hormonal contraceptives) and those in whom revascularization, such as coronary arterial bypass, fails because of rapid occlusion of the graft.
A diagnosis of TTP is based on the clinical symptoms with the concomitant presence of thrombocytopenia (platelet count below 100×10/L) and microangiopathic hemolytic anemia with schistocytes on the blood smear, a negative direct antiglobulin test (coombs test), elevated levels of hemolysis markers (such as total bilirubin, LDH, free hemoglobin and an unmeasurable haptoglobin), after exclusion of any other apparent cause.
USS can present similar to the following diseases which have to be excluded: fulminant infections, disseminated intravascular coagulation, autoimmune hemolytic anemia, Evans syndrome, the typical and atypical form of hemolytic uremic syndrome (HUS), HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome, pre-eclampsia, heparin-induced thrombocytopenia (HIT), cancer that is often accompanied with metastasis, kidney injury, antiphospholipid antibody syndrome and side effects from hematopoietic stem cell transplantation.
Of note is that pregnancy associated affections like pre-eclampsia, eclampsia and HELLP syndrome can overlap in their presentation as pregnancy can trigger TTP episodes.
Patients with fulminant infections, disseminated intravascular coagulation, HELLP syndrome, pancreatitis, liver disease and other active inflammatory conditions may have reduced ADAMTS13 activity but almost never a relevant severe ADAMTS13 deficiency <10% of the normal.
A severe ADAMTS13 deficiency below 5% or <10% of the normal (depending on the definitions) is highly specific for the diagnosis of TTP. ADAMTS13 activity assays are based on the direct or indirect measurement of VWF-cleavage products. Its activity should be measured in blood samples taken before therapy has started, to prevent false high ADAMTS13 activity. If a severe ADAMTS13 deficiency is present an ADAMTS13 inhibitor assay is needed to distinguish between the acquired, autoantibody-mediated and the congenital form of TTP (USS). The presence of antibodies can be tested by ELISA or functional inhibitor assays. The level of ADAMTS13 inhibitor may be fluctuating over the course of disease and depends on free circulatory antibodies, therefore an onetime negative test result does not always exclude the presence of ADAMTS13 inhibitors and thereby an autoimmune origin of TTP. A severe ADAMTS13 deficiency in the absence of an inhibitor, confirmed on a second time point in a healthy episode of a possible USS patient, usually sets the trigger to perform a molecular analysis of the "ADAMTS13" gene to confirm a mutation. In unclear cases a plasma infusion trial can be done, showing an USS in the absence of anti-ADAMTS13-antibodies a full recovery of infused plasma-ADAMTS13 activity as well as a plasma half-life of infused ADAMTS13 activity of 2–4 days. A deficiency of ADAMTS13 activity in first-degree relatives is also a very strong indicator for an Upshaw-Schulman Syndrome.
The diagnosis of HPS is established by clinical findings of hypopigmentation
of the skin and hair, characteristic eye findings, and demonstration of absent
dense bodies on whole mount electron microscopy of platelets. Molecular
genetic testing of the HPS1 gene is available on a clinical basis for
individuals from northwestern Puerto Rico. Molecular testing of the HPS3 gene
is available on a clinical basis for individuals of central Puerto Rican or
Ashkenazi Jewish heritage. Sequence analysis is available on a clinical basis
for mutations in HPS1 and HPS4. Diagnosis of individuals with other types of
HPS is available on a research basis only.
Recommended treatment of asymptomatic congenital hypofibrinogenemia depends in part on the expectations of developing bleeding and/or thrombotic complications as indicated by the personal history of the afflicted individual and family members. Where possible, determination of the exact mutation causing the disorder and the propensity of this mutation type to develop these complications may be helpful. Individuals with fibrinogen levels >1.0 gram/liter typically do not develop bleeding or thrombosis episodes. Individuals with fibrinogen levels of 0.5-1.0 grams/liter require fibrinogen supplementation preferably with a plasma-derived fibrinogen concentrate to maintain fibrinogen levels of >1 gram/liter prior to major surgery. Individuals with fibrinogen levels of 1 to 2 gram/liter at the end of pregnancy and during the postpartum period; b) > 1 gram/liter prior to major surgery; c) > 0.5 to 1 gram/liter during the first two trimesters of pregnancy; and d) >0.5 gram/liter prior to minor surgery. Tranexamic acid may be used in place of fibrinogen supplementation as prophylactic treatment prior to minor surgery and to treat minor bleeding episodes.
The diagnosis for deficiency of protein S can be done via reviewing family history of condition and genetic testing, as well as the following:
- Protein S antigen test
- Coagulation test (prothrombin time test)
- Thrombotic disease investigation
- Factor V Leiden test
When a problem of fibrinogen is suspected, the following tests can be ordered:
- PT
- PTT
- Fibrinogen level in blood (total and clottable)
- Reptilase time
- Thrombin time
Blood fibrinogen levels of less than 0.1 g/L and prolonged bleeding test times are indicators of an individual having afibrinogenemia.
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):
In congenital FXII deficiency treatment is not necessary. In acquired FXII deficiency the underlying problem needs to be addressed.
There are several treatments available for factor VII deficiency; they all replace deficient FVII.
1. Recombinant FVIIa concentrate (rFVIIa) is a recombinant treatment that is highly effective and has no risk of fluid overload or viral disease. It may be the optimal therapy.
2. Plasma derived Factor VII concentrate (pdFVII) : This treatment is suitable for surgery but can lead to thrombosis. It is virus attenuated.
3. Prothrombin complex concentrate (PCC) containing factor VII: this treatment is suitable for surgery, but has a risk of thrombosis. It is virus attenuated.
4. Fresh frozen plasma (FFP): This is relatively inexpensive and readily available. While effective this treatment carries a risk of blood-borne viruses and fluid overload.
The incidence of acute TTP in adults is around 1.7–4.5 per million and year. These cases are nearly all due to the autoimmune form of TTP, where autoantibodies inhibit ADAMTS13 activity. The prevalence of USS has not yet been determined but is assumed to constitute less than 5% of all acute TTP cases. The syndrome's inheritance is autosomal recessive, and is more often caused by compound heterozygous than homozygous mutations. The age of onset is variable and can be from neonatal age up to the 5th–6th decade. The risk of relapses differs between affected individuals. Minimization of the burden of disease can be reached by early diagnosis and initiation of prophylaxis if required.
The diagnosis for hemophilia B can be done via the following tests/methods:
- Coagulation screening test
- Bleeding scores
- Coagulation factor assays
The most common treatments are transfusions of cryoprecipitate or blood plasma to help with bleeding episodes or prior to surgery. There are no known cures or forms of holistic care to date. Most complications arise from the symptoms of the disorder. As there is not much data out on the life expectancy of an individual with afibrinogenemia, it is difficult to determine the average lifespan. However, the leading cause of death thus far is linked to CNS hemorrhage and postoperative bleeding.
The differential diagnosis for this inherited condition is the following: hemophilia A, factor XI deficiency, von Willebrand disease, fibrinogen disorders and Bernard-Soulier syndrome
Two of the most common differential diagnoses are haemophilia B which is a deficiency in Factor IX and von Willebrand Disease which is a deficiency in von Willebrand factor (needed for the proper functioning of Factor VIII), haemophilia C is also a possible, differential diagnosis.
Diagnosis of inherited hypoprothrombinemia, relies heavily on a patient's medical history, family history of bleeding issues, and lab exams performed by a hematologist. A physical examination by a general physician should also be performed in order to determine whether the condition is congenital or acquired, as well as ruling out other possible conditions with similar symptoms. For acquired forms, information must be taken regarding current diseases and medications taken by the patient, if applicable.
Lab tests that are performed to determine diagnosis:
1. Factor Assays: To observe the performance of specific factors (II) to identify missing/poorly performing factors. These lab tests are typically performed first in order to determine the status of the factor.
2. Prothrombin Blood Test: Determines if patient has deficient or low levels of Factor II.
3. Vitamin K1 Test: Performed to evaluate bleeding of unknown causes, nosebleeds, and identified bruising. To accomplish this, a band is wrapped around the patient's arm, 4 inches above the superficial vein site in the elbow pit. The vein is penetrated with the needle and amount of blood required for testing is obtained. Decreased vitamin K levels are suggestive of hypoprothrombinemia. However, this exam is rarely used as a Prothrombin Blood Test is performed beforehand.
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.
The diagnostic workup is directed by the presenting signs and symptoms, and can involve:
- blood counts, clotting studies, and other laboratory testing
- imaging tests (ultrasound, CT scan, MRI, sometimes angiography, and rarely nuclear medicine scans)
- biopsy of the tumor.
Patients uniformly show severe thrombocytopenia, low fibrinogen levels, high fibrin degradation products (due to fibrinolysis), and microangiopathic hemolysis.