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.

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.

In a study of 189 individuals diagnosed with congenital dysfibrinogenemia, ~33% were asymptomatic, ~47% experienced episodic bleeding, and ~20% experienced episodic thromboses. Due to the rareness of this disorder, treatment of individuals with these presentations are based primarily on case reports, guidelines set by the United Kingdom, and expert opinions rather than controlled clinical studies.

HIT may be suspected if blood tests show a falling platelet count in someone receiving heparin, even if the heparin has already been discontinued. Professional guidelines recommend that people receiving heparin have a complete blood count (which includes a platelet count) on a regular basis while receiving heparin.

However, not all people with a falling platelet count while receiving heparin turn out to have HIT. The timing, severity of the thrombocytopenia, the occurrence of new thrombosis, and the presence of alternative explanations, all determine the likelihood that HIT is present. A commonly used score to predict the likelihood of HIT is the "4 Ts" score introduced in 2003. A score of 0–8 points is generated; if the score is 0-3, HIT is unlikely. A score of 4–5 indicates intermediate probability, while a score of 6–8 makes it highly likely. Those with a high score may need to be treated with an alternative drug while more sensitive and specific tests for HIT are performed, while those with a low score can safely continue receiving heparin as the likelihood that they have HIT is extremely low. In an analysis of the reliability of the 4T score, a low score had a negative predictive value of 0.998, while an intermediate score had a positive predictive value of 0.14 and a high score a positive predictive value of 0.64; intermediate and high scores therefore warrant further investigation.

The first screening test in someone suspected of having HIT is aimed at detecting antibodies against heparin-PF4 complexes. This may be with a laboratory test of the ELISA (enzyme-linked immunosorbent assay) type. The ELISA test, however, detects all circulating antibodies that bind heparin-PF4 complexes, and may also falsely identify antibodies that do not cause HIT. Therefore, those with a positive ELISA are tested further with a functional assay. This test uses platelets and serum from the patient; the platelets are washed and mixed with serum and heparin. The sample is then tested for the release of serotonin, a marker of platelet activation. If this serotonin release assay (SRA) shows high serotonin release, the diagnosis of HIT is confirmed. The SRA test is difficult to perform and is usually only done in regional laboratories.

If someone has been diagnosed with HIT, some recommend routine Doppler sonography of the leg veins to identify deep vein thromboses, as this is very common in HIT.

Tests for thrombophilia include complete blood count (with examination of the blood film), prothrombin time, partial thromboplastin time, thrombodynamics test, thrombin time and reptilase time, lupus anticoagulant, anti-cardiolipin antibody, anti-β2 glycoprotein 1 antibody, activated protein C resistance, fibrinogen tests, factor V Leiden and prothrombin mutation, and basal homocysteine levels. Testing may be more or less extensive depending on clinical judgement and abnormalities detected on initial evaluation.

For hereditary cases, the patient must have at least 2 abnormal tests plus family history.

Suspicion of factor V Leiden being the cause for any thrombotic event should be considered in any Caucasian patient below the age of 45, or in any person with a family history of venous thrombosis.

There are a few different methods by which this condition can be diagnosed. Most laboratories screen 'at risk' patients with either a snake venom (e.g. dilute Russell's viper venom time) based test or an aPTT based test. In both methods, the time it takes for blood to clot is decreased in the presence of the factor V Leiden mutation. This is done by running two tests simultaneously; one test is run in the presence of activated protein C (APC) and the other, in the absence. A ratio is determined based on the two tests and the results signify to the laboratory whether APC is working or not.

There is also a genetic test that can be done for this disorder. The mutation (a 1691G→A substitution) removes a cleavage site of the restriction endonuclease "MnlI", so PCR, treatment with "MnlI", and then DNA electrophoresis will give a diagnosis. Other PCR based assays such as iPLEX can also identify zygosity and frequency of the variant.

Hypodysfibrinogenemia is usually diagnosed in individuals who: have a history of abnormal bleeding or thrombosis or are a close blood relative of such an individual. Initial laboratory findings include a decrease in serum fibrinogen mass levels as measured by immunoassay plus a reduction in inducible blood clot formation so that the ratio of functionally-detected fibrinogen mass (i.e. detected in induced clots) to immunoassay-detected fibrinogen mass is abnormally low, i.e. <0.7. This contrast with individuals with congenital dysfibrinogenemia who exhibit normal levels of fibrinogen as measured by immunoassay but low functionally-detected to immunoassay-detected fibrinogen mass ratios, i.e. <0.7. Where available, specialized laboratories can conduct studies to define the exact gene mutation(s) and fibrinogen abnormalities underlying the disorder.

People may be diagnosed after prolonged and/or recurring bleeding episodes. Children and adults may also be diagnosed after profuse bleeding after a trauma or tooth extraction. Ultimately, a laboratory diagnosis is usually required. This would utilize platelet aggregation studies and flow cytometry.

TTP is characterized by thrombotic microangiopathy (TMA), the formation of blood clots in small blood vessels throughout the body, which can lead to microangiopathic hemolytic anemia and thrombocytopenia. This characteristic is shared by two related syndromes, hemolytic-uremic syndrome (HUS) and atypical hemolytic uremic syndrome (aHUS). Consequently, differential diagnosis of these TMA-causing diseases is essential. In addition to TMA, one or more of the following symptoms may be present in each of these diseases: neurological symptoms (e.g. confusion, cerebral convulsions seizures,); kidney impairment (e.g. elevated creatinine, decreased estimated glomerular filtration rate [eGFR], abnormal urinalysis); and gastrointestinal (GI) symptoms (e.g. diarrhea nausea/vomiting, abdominal pain, gastroenteritis. Unlike HUS and aHUS, TTP is known to be caused by an acquired defect in the ADAMTS13 protein, so a lab test showing ≤5% of normal ADAMTS13 levels is indicative of TTP. ADAMTS13 levels above 5%, coupled with a positive test for shiga-toxin/enterohemorrhagic "E. coli" (EHEC), are more likely indicative of HUS, whereas absence of shiga-toxin/EHEC can confirm a diagnosis of aHUS.

Anti-platelet autoantibodies in a pregnant woman with ITP will attack the patient's own platelets and will also cross the placenta and react against fetal platelets. Therefore, ITP is a significant cause of fetal and neonatal immune thrombocytopenia. Approximately 10% of newborns affected by ITP will have platelet counts <50,000/uL and 1% to 2% will have a risk of intracerebral hemorrhage comparable to infants with neonatal alloimmune thrombocytopenia (NAIT).

No lab test can reliably predict if neonatal thrombocytopenia will occur. The risk of neonatal thrombocytopenia is increased with:

- Mothers with a history of splenectomy for ITP

- Mothers who had a previous infant affected with ITP

- Gestational (maternal) platelet count less than 100,000/uL

It is recommended that pregnant women with thrombocytopenia or a previous diagnosis of ITP should be tested for serum antiplatelet antibodies. A woman with symptomatic thrombocytopenia and an identifiable antiplatelet antibody should be started on therapy for their ITP which may include steroids or IVIG. Fetal blood analysis to determine the platelet count is not generally performed as ITP-induced thrombocytopenia in the fetus is generally less severe than NAIT. Platelet transfusions may be performed in newborns, depending on the degree of thrombocytopenia. It is recommended that neonates be followed with serial platelet counts for the first few days after birth.,

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.

CBC and blood film: decreased platelets and schistocytes PT, aPTT, fibrinogen: normal Markers of hemolysis: increased unconjugated bilirubin, increased LDH, decreased haptoglobin Negative Coombs test

Creatinine, urea, to follow renal function ADAMSTS-13 gene, activity or inhibitor testing (TTP)

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 DIC is not made on a single laboratory value, but rather the constellation of laboratory markers and a consistent history of an illness known to cause DIC. Laboratory markers consistent with DIC include:

- Characteristic history (this is important because severe liver disease can essentially have the same laboratory findings as DIC)

- Prolongation of the prothrombin time (PT) and the activated partial thromboplastin time (aPTT) reflect the underlying consumption and impaired synthesis of the coagulation cascade.

- Fibrinogen level has initially thought to be useful in the diagnosis of DIC but because it is an acute phase reactant, it will be elevated due to the underlying inflammatory condition. Therefore, a normal (or even elevated) level can occur in over 57% of cases. A low level, however, is more consistent with the consumptive process of DIC.

- A rapidly declining platelet count

- High levels of fibrin degradation products, including D-dimer, are found owing to the intense fibrinolytic activity stimulated by the presence of fibrin in the circulation.

- The peripheral blood smear may show fragmented red blood cells (known as schistocytes) due to shear stress from thrombi. However, this finding is neither sensitive nor specific for DIC

A diagnostic algorithm has been proposed by the International Society of Thrombosis and Haemostasis. This algorithm appears to be 91% sensitive and 97% specific for the diagnosis of overt DIC. A score of 5 or higher is compatible with DIC and it is recommended that the score is repeated daily, while a score below 5 is suggestive but not affirmative for DIC and it is recommended that it is repeated only occasionally: It has been recommended that a scoring system be used in the diagnosis and management of DIC in terms of improving outcome.

- Presence of an underlying disorder known to be associated with DIC (no=0, yes=2)

- Global coagulation results

- Platelet count (>100k = 0, <100 = 1, <50 = 2)

- Fibrin degradation products such as D-Dimer (no increase = 0, moderate increase = 2, strong increase = 3)

- Prolonged prothrombin time (3 sec = 1, >6 sec = 2)

- Fibrinogen level (> 1.0g/L = 0; < 1.0g/L = 1)

Studies have found that about 5 percent of Caucasians in North America have factor V Leiden. The condition is less common in Latin Americans and African-Americans and is extremely rare in people of Asian descent.

Up to 30 percent of patients who present with deep vein thrombosis (DVT) or pulmonary embolism have this condition. The risk of developing a clot in a blood vessel depends on whether a person inherits one or two copies of the factor V Leiden mutation. Inheriting one copy of the mutation from a parent (heterozygous) increases by fourfold to eightfold the chance of developing a clot. People who inherit two copies of the mutation (homozygous), one from each parent, may have up to 80 times the usual risk of developing this type of blood clot. Considering that the risk of developing an abnormal blood clot averages about 1 in 1,000 per year in the general population, the presence of one copy of the factor V Leiden mutation increases that risk to between 4 in 1,000 to 8 in 1,000. Having two copies of the mutation may raise the risk as high as 80 in 1,000. It is unclear whether these individuals are at increased risk for "recurrent" venous thrombosis. While only 1 percent of people with factor V Leiden have two copies of the defective gene, these homozygous individuals have a more severe clinical condition. The presence of acquired risk factors for venous thrombosis—including smoking, use of estrogen-containing (combined) forms of hormonal contraception, and recent surgery—further increase the chance that an individual with the factor V Leiden mutation will develop DVT.

Women with factor V Leiden have a substantially increased risk of clotting in pregnancy (and on estrogen-containing birth control pills or hormone replacement) in the form of deep vein thrombosis and pulmonary embolism. They also may have a small increased risk of preeclampsia, may have a small increased risk of low birth weight babies, may have a small increased risk of miscarriage and stillbirth due to either clotting in the placenta, umbilical cord, or the fetus (fetal clotting may depend on whether the baby has inherited the gene) or influences the clotting system may have on placental development. Note that many of these women go through one or more pregnancies with no difficulties, while others may repeatedly have pregnancy complications, and still others may develop clots within weeks of becoming pregnant.

Hydroxycarbamide and anagrelide are contraindicated during pregnancy and nursing. Essential thrombocytosis can be linked with a three-fold increase in risk of miscarriage. Throughout pregnancy, close monitoring of the mother and fetus is recommended. Low-dose low molecular weight heparin (e.g. enoxaparin) may be used. For life-threatening complications, the platelet count can be reduced rapidly using platelet apheresis, a procedure that removes platelets from the blood and returns the remainder to the patient.

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.

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.

There are several groups where screening for PNH should be undertaken. These include patients with unexplained thrombosis who

are young, have thrombosis in an unusual site (e.g. intra-abdominal veins, cerebral veins, dermal veins), have any evidence of hemolysis (i.e. a raised LDH), or have a low red blood cell, white blood cell, or platelet count. Those who have a diagnosis of aplastic anemia should be screened annually.

Blood relatives of the proband case should be evaluated for the presence of hypodysfibrinogenemia. Individuals with the disorder need to be advised on its inheritance, complications, and preventative measures that can be taken to avoid bleeding and/or thrombosis. Since >80% of individuals may develop bleeding or thrombosis complications of the disorder, asymptomatic individuals diagnosed with hydposyfibrinogenemia are best handled at a specialized center in order to benefit from multidisciplinary management.

Measures to prevent and/or treat complications of hypodysfibrinogenemia should be tailored to the personal and family history of the individual by a specialized center. Individuals with a personal or family history of bleeding are considered to be of low risk of bleeding when their functional fibrinogen levels are >1 gram/liter for major surgery, >0.5 gram/liter for minor surgery, >0.5 to 1-2 gram/liter for spontaneous bleeding (depending on its severity), >0.5 to > 1 gram/liter for the first two trimesters of pregnancy, and >1 to <2 gram/liter for the last trimester of pregnancy and postpartum period. Functional fibrinogen below these levels should be treated preferably with fibrinogen concentrate or if not available, fibrinogen-rich cryoprecipitate or plasma to attain low risk levels of functional fibrinogen. Antifibrinolytic drugs such as tranexamic acid or (ε-aminocaproic acid) may be considered as an alternative preventative or therapeutic treatments in cases of minor surgery, dental extractions, mucosal bleeding, or other episodes of mild bleeding. In individuals with a personal or family history of thrombosis, should be considered for long-term anticoagulation drugs such as low molecular weight heparin, coumadin, or rivaroxaban.

Antiphospholipid syndrome is tested for in the laboratory using both liquid phase coagulation assays (lupus anticoagulant) and solid phase ELISA assays (anti-cardiolipin antibodies).

Genetic thrombophilia is part of the differential diagnosis of APS and can coexist in some APS patients. Presence of genetic thrombophilia may determine the need for anticoagulation therapy. Thus genetic thrombophilia screening can consist of:

- Further studies for factor V Leiden variant and the prothrombin G20210A mutation, factor VIII levels, MTHFR mutation.

- Levels of protein C, free and total protein S, factor VIII, antithrombin, plasminogen, tissue plasminogen activator (TPA) and plasminogen activator inhibitor-1 (PAI-1)

The testing of antibodies to the possible individual targets of aPL such as β glycoprotein 1 and antiphosphatidyl serine is currently under debate as testing for anticardiolipin appears to be currently sensitive and specific for diagnosis of APS even though cardiolipin is not considered an in vivo target for antiphospholipid antibodies.

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.

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

The differential diagnosis for Bernard–Soulier syndrome includes both Glanzmann thrombasthenia and pediatric Von Willebrand disease. BSS platelets do not aggregate to ristocetin, and this defect is not corrected by the addition of normal plasma, distinguishing it from von Willebrand disease.

In adults, particularly those living in areas with a high prevalence of "Helicobacter pylori" (which normally inhabits the stomach wall and has been associated with peptic ulcers), identification and treatment of this infection has been shown to improve platelet counts in a third of patients. In a fifth, the platelet count normalized completely; this response rate is similar to that found in treatment with rituximab, which is more expensive and less safe. In children, this approach is not supported by evidence, except in high prevalence areas. Urea breath testing and stool antigen testing perform better than serology-based tests; moreover, serology may be false-positive after treatment with IVIG.