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In 2008, we decided to enter the era of direct oral anticoagulants (DOACS). Was that the right decision to make? The answer will depend on how well we meet the conditions of proper use. This means avoiding underdosing and overdosing as well as understanding how DOACS were validated so that our prescriptions fulfill their role in the management of thrombotic disease.

Despite the increasing utilization of direct oral anticoagulant (DOAC) prescriptions, vitamin K antagonists (VKAs) remain the treatment of choice for treating and preventing thromboembolic events. The morbidity and mortality of VKAs are partly due to the difficulty of keeping the patient within the therapeutic range. For patients treated by VKA, time in therapeutic range (TTR) is a quality parameter of treatment, widely used in clinical trials but rarely by prescribers. It is well established that its use correlates with the risk of hemorrhage, thrombosis or mortality. We studied this parameter in a cohort of patients to evaluate the quality of their therapeutic follow-up and tried to identify risk factors for low TTR.The study was made in collaboration with LaboSud Oc Biologie for a duration of 4 months. It included 3387 patients representing 2,4029 INR. We calculated the patients' TTR. The laboratory transmitted to us the sex and age of each patient and the VKA molecule used, the therapeutic range and the specialty of the prescriber. We then analyzed the odds ratio associated with these different factors.The mean TTR was 68%, close to the TTR recommended by scientific societies. Patient's sex was the only statistically correlated factor, with a worse equilibrium in females taking VKAs (OR=1.22, 95% CI: 1.06-1.39, P=0.00552). Many factors usually correlated with poor equilibrium under VKA have not been studied due to lack of information.Given the context of economic restriction and the TTR of our cohort close to the recommended 70%, there would be no benefit in terms of safety to prefer DOAC for the patients involved in this study. Regular monitoring of the individual patient's as well as the cohort's TTR should optimize the management of patients receiving VKAs.

Vitamin K antagonists (VKA) and direct oral anticoagulants (DOACs) are now in competition. The companies are trying to replace VKA by DOACs, totally or at least greatly VKA should VKA disappear in favor of DOACs? There are still many questions about DOACs. The purpose of this article is to make a well-considered decision in this area. The aim is not to denigrate one or the other but to share things between these two families of anticoagulants. Physicians using these drugs must have a full knowledge about compared efficacy and safety. We feel necessary to increase distance between effective results of the clinical trials and industrial communication around DOACs.

International audience; Until 1990, congenital hemorrhagic disorders were treated by plasma-derived concentrates. The first recombinant drug, recombinant factor VIII was available after this date and few years later recombinant factor IX could also be proposed to patients. The evolution of market share in France was different between these two drugs: while recombinant factor VIII took a large place in hemophilia A treatment (85%), plasma-derived factor IX represent 50% of the French market. In the next years, the arrival of long-acting antihemophilic factors may lead to the dramatically reduce the amount of plasma-derived antihemophilic factors used to treat hemophilia. For rare bleeding coagulation disorders, plasma-derived concentrates are still widely used, while they are the only concentrates available in most diseases. This situation is unlikely to evolve significantly in the next years.

International audience; Venous thromboembolism disease (VTE) is rare in children (5.3 of 10,000 hospitalized children). However, morbidity and mortality are high, especially when the child is already suffering from severe sepsis. We report an analytical study of 24 cases of deep venous thrombosis occurring in children during infection, recorded at the Montpellier University Hospital between 1999 and 2009. Many parameters were studied in each population (age, sex, familial and personal history of thrombosis, history of thrombophilia, the presence of a venous catheter, a causative organism, time to onset of thrombus, topography of lesions, acquired abnormalities of hemostasis, and thrombosis prophylaxis). The children were aged from 1 day of life to 16 years. Thromboses occurred in two clinical contexts: "contact" thrombosis (which appeared near the infection) and disseminated thrombosis. This is an early complication because in most of the cases, it appeared in the first 10 days of sepsis. Infection and coagulation appear to be closely related and the states of latent or decompensated disseminated intravascular coagulation are common. Nevertheless, it is not possible to predict the occurence of a thrombotic event. The presence of risk factors (venous catheters, acquired thrombophilia, or constitutional thrombophilia) may increase the thrombogenic potential of the infection. VTE should always be suspected and sought in case of an unfavorable clinical course, and routine prophylaxis of thrombosis during sepsis should be discussed.

New direct oral anticoagulants (NOAC), inhibitors of factor IIa or Xa, are expected to be widely used for the treatment of venous thromboembolic disease, or in case of atrial fibrillation. Such anticoagulant treatments are known to be associated with haemorrhagic complications. Moreover, it is likely that such patients on long-term treatment with NOAC will be exposed to emergency surgery or invasive procedures. Due to the present lack of experience in such conditions, we cannot make recommendations, but only propose management for optimal safety as regards the risk of bleeding in such emergency conditions. In this article, only dabigatran and rivaroxaban were discussed. For emergency surgery at risk of bleeding, we propose to dose the plasmatic concentration of drug. Levels inferior or equal to 30ng/mL for both dabigatran and rivaroxaban, should enable the realization of a high bleeding risk surgery. For higher concentration, it was proposed to postpone surgery by monitoring the evolution of the drug concentration. Action is then defined by the kind of NOAC and its concentration. If the dosage of the drug is not immediately available, proposals only based on the usual tests, PT and aPTT, also are presented. However, these tests do not really assess drug concentration or bleeding risk. In case of severe haemorrhage in a critical organ, it is proposed to reduce the effect of anticoagulant therapy using a nonspecific procoagulant drug (activated prothrombin concentrate, FEIBA, 30-50U/kg, or non-activated 4-factors prothrombin concentrates 50U/kg). For any other type of severe haemorrhage, the administration of such a procoagulant drug, potentially thrombogenic in these patients, will be discussed regarding concentration of NACO and possibilities for mechanical haemostasis.

Rare inherited bleeding disorders include fibrinogen disorders, and deficiencies of factors II (prothrombin), V, VII, X, XI, XIII, and combined V+VIII, and combined vitamin K-dependent factors, with general population prevalence rates between 1/500,000 and 1/2,000,000. These inherited disorders, transmitted as autosomal recessive traits, are characterized by a heterogeneous clinical presentation (asymptomatic, mild, moderate or severe bleeding tendency); this variability is more important for deficiencies with factor levels ranging from 5 to 50%. Individual bleeding risk assessment before an invasive procedure or during peri-partum period remains difficult, although an essential step to decide whether a substitution with clotting factor is necessary or not. Because there is a poor correlation between factor activity levels and the severity of bleeding symptoms, factor correction before an invasive procedure should not be based on factor level only, but physicians must also take into account the patient phenotype as well as the haemorrhagic risk of the procedure.

Aspirin, a 110-year-old molecule, is a cornerstone in the treatment of atherothrombotic patients. The concept of aspirin "resistance" emerged approximately 15 years ago and is of growing interest. Aspirin resistance, defined as a lack of inhibition of cyclo-oxygenase-1 (COX-1), is a rare phenomenon and its clinical relevance can hardly be studied. On the contrary, residual platelet hyperactivity is more common and affects 20 to 30% of aspirin-treated patients. This latter phenomenon corresponds to sustained platelet reactivity despite a proper inhibition of COX-1 by aspirin. Several meta-analyses suggest that residual platelet hyperactivity could be a risk factor for the recurrence of ischemic events in aspirin-treated patients. Causes of biological non-responsiveness to aspirin are discussed, including the role of compliance, drug-drug interactions, genetic polymorphisms and diabetes mellitus. Ongoing studies are designed to find out the mechanisms of residual platelet hyperactivity, determine its potential clinical relevance and delineate the more appropriate assays in order to identify patients who may benefit of a tailored antiplatelet therapy.

The authors had for aim to review pediatric cases of EBV-associated hemophagocytic lymphohistiocytosis observed, between January 1999 and December 2007, to compare their characteristics to literature data, and to suggest a pragmatic strategy for diagnosis and treatment.The following were analyzed for each patient: age at diagnosis, family history, revised Henter diagnostic criteria, EBV serology and/or PCR, results of genetic studies when available, treatment, short and long-term outcome.Four patients 11 months to seven years of age were admitted for high and prolonged fever, hepato and/or splenomegaly, and biological markers of hemophagocytic lymphohistiocytosis. They were all initially treated with corticosteroids. The outcome was severe for the two younger patients, with acute hepatocellular failure leading to death for the first, and severe neurological impairment for the second. The two older patients responded well to corticosteroids alone, and are alive. There was no recurrence at the end of the study.Hemophagocytic lymphohistiocytosis is the most severe complication of infectious mononucleosis. A primary cytotoxicity deficiency must be ruled out, especially in children under two years of age. Treatment is consensus free, but many studies report interesting results in terms of outcome with regimens including etoposide.

The use of preoperative autologous blood transfusion has dramatically decreased in France. The aim of this study was to evaluate the evolution of practice both of autologous and homologous Red Blood Cells (RBC) concentrates transfusion between 2002 and 2005, and to asses the consequences of the highlighted changes.Data on blood transfusion are collected and validated nationwide by a network of regional coordinators of haemovigilance. For each hospital, from 2002 to 2005, the annual changes in the number of transfused homologous and autologous RBC have been evaluated. The ratio of preoperative autologous RBC, number of autologous RBC divided by the number of all RBC, has also been calculated. Hospitals have been split into three cohorts, according to their 2005 autologous RBC ratio. For each cohort, correlations between the variations of the number of autologous, homologous and total RBC in each hospital have been studied.Data have been validated for 22 French regions that performed 71.8% of the total French transfusion in 2004. In 2005, 1,831,544 labile blood products have been transfused in 1197 hospitals and clinics among which 379 have used preoperative autologous transfusion. A total of 37,289 autologous RBC have been transfused in 2003, 28,689 in 2004 (-23.1%) and 17,758 in 2005 (-38.1%). The first cohort of 269 hospitals had a ratio of autologous RBC under 3%, the second cohort of 38 hospitals, a ratio between 3 and 6%, while the third cohort of 72 hospitals had transfused 6% or more of autologous RBC. In the two first cohorts, non-surgical activities were so large that it was impossible to assess the changes in surgical use of transfusion. The third cohort, with a ratio of 6% or more, was essentially devoted to surgery (88% of beds). These hospitals and clinics have transfused 13,076 autologous RBC in 2002 and 8583 in 2005 (-34.4%). In this group, there was a statistical correlation between the decrease of autologous RBC and the decrease of total RBC (r(2)=0.36), and no increase in the transfusion of homologous RBC has been observed. During the same period, neither hospitals nor clinics showed any decrease of their surgical activity. The drop of autologous RBC transfusion led to a decrease of the total number of RBC transfused and thus, to a decrease of the global exposure to transfusion hazard.The present results confirmed a decline of preoperative autologous transfusion in France, between 2002 and 2005. Meanwhile no supplementary need of homologous RBC has been observed among hospitals, performing surgery that formerly had a high ratio of autologous RBC.

Epidemiological studies suggest that estrogens may have opposite effects on vessels: estrogens used for contraception are known to increase both arterial and venous risk, while hormone replacement therapy could reduce the risk of cardiovascular disease. In both situations, estrogens are associated with progestogens. Progestogens are rarely used alone, thus the effect of progestogens on haemostasis or vessel wall is unclear. Data can be obtained from studies using progestogens alone or from studies comparing unopposed estrogens to combined estrogen-progestogen therapy. Progestogens alone have few effect on the haemostatic system. In combined therapy used for contraception, progestogens modify the effects of estrogens on haemostasis and endothelium: the overall effect, including modifications of coagulation factors and inhibitors could a prothrombogen trend, mainly for third generation progestogens. Unopposed estrogens are also rarely used for post menopausal hormone replacement therapy (HRT). Experimental studies have shown that progestogens are able to inhibit the beneficial effect of estrogens. Two mechanisms have been suggested: first, progestogens may reduce the endothelium-dependent vasodilatator action of estrogens. Another explanation concerns the neointimal proliferation leading to atherosclerosis: Estradiol are known to reduce this proliferation. Progestogens could reduce the protective effect of estrogens. These pharmacological effect of progestogens must be taken in account to interpret the negative results of HERS study that failed to demonstrate a cardiovascular benefit of estrogens plus progestin therapy in postmenopausal women.

Twenty-nine patients, 15 to 85-year-old (mean: 50 years) who presented with a pleural effusion after trauma were studied. The blood content of pleural fluid was confirmed by thoracocentesis. None of the patients had been taking anticoagulant drugs during the fortnight preceding the trauma. Thoracocentesis was always carried out less than 90 min after the trauma. The following parameters were measured in the haemothorax liquid samples: clotting fibrinogen fraction (Fg C), fibrin degradation D-dimers, functional plasminogen, alpha 2-antiplasmin, alpha 2-macroglobulin, plasminogen tissue activator (tPA Ag), type 1 tPA plasma inhibitor (PAI), and haematocrit. Haemothorax liquid haematocrit values ranged from 13 to 35% (25 +/- 7%, with a mean peripheral venous haematocrit of 34 +/- 6%). Only three patients had some Fg C (0.05-0.13 g.l-1). The D-dimer level was very high (0.23 +/- 0.22 g.l-1). The other factors involved in fibrinolysis were also present. Moreover, there was a statistically significant inverse correlation between D-dimer and alpha 2-macroglobulin levels (r = -0.64, p less than 0.0025). These data suggest two possible mechanisms to explain the fibrinogen levels: coagulation is activated, followed by an important fibrinolytic reaction elicited by the large amounts of plasminogen and tPA present in the haemothorax liquid.

Exploration of haemostasis was performed on plasmas thawed in an experimental microwave oven comparatively to a 37 degrees C water bath. Factor VIII:R:Ag, procoagulant and antigenic fibrinogen, and Fg:C/Fg:Ag ratio were found to be significantly, slightly decreased with microwave thawing. Factor VIII:C and VIII:C/VIII:R:Ag ratio were found to be increased with microwaves. Antigenic fractions were decreased because of partial precipitation. In addition, Fibrinogen slightly lost its activity; on the contrary, factor VIIIC was activated by micro-waves. All this allows to select parameters for new experimental microwave ovens development.

A 19-year old male patient with hereditary antithrombin III type I deficiency was admitted for thrombosis of the right iliac, femoral and popliteal veins. Treatment with a low molecular weight heparin resulted in recanalization of the veins confirmed by phlebography. After two weeks of treatment, the drug was replaced by another low molecular weight heparin and this was followed, 3 weeks later, by a documented relapse of thrombosis.

This open, randomised multicenter trial compares the efficacy and safety of Fragmin administered subcutaneously twice daily with standard heparin administered by continuous infusion in the treatment of deep vein thrombosis (DVT). The initial dose of Fragmin is 100 U anti-Xa/kg/12 h and the further doses are adjusted according to the anti-Xa activity between 0.5 and 0.8 U/ml, 3 hours after the morning injection. The initial dose of standard heparin is 240 UI/kg/12 h. The dose adjustments are based on the daily results of APTT (1.5 - 3 times the control). Treatments efficacy are appreciated when comparing the venography performed before and after 10 days of treatment. The safety is evaluated on clinical parameters and iterative biological tests. Sixty-six patients have been included in this study. Efficacy of the two treatments is equivalent with a phlebographic improvement in respectively 79.3 p. 100 (Heparin Group) and 71.0 p. 100 (Fragmin Group) of the cases and an aggravation in 3.4 p. 100 and 6.4 p. 100 (NS) respectively. The frequency of dosage adjustments is lower and the stability of biological tests is better in the Fragmin group. In conclusion, the administration of Fragmin twice daily by subcutaneous route seems to be equivalent at least to standard heparin continuous infusion in the treatment of recent DVT. The better convenience and safety of Fragmin have to be verified on a larger panel of patients.