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Introduction: We aimed at evaluating the performance of a new prothrombin time (PT) reagent (STA-NeoPTimal) with two other PT reagents (STA-Neoplastine R and STA-Neoplastine CI Plus) and the reference PT reagent used in our laboratory (ReadiPlasTin)., Methods: Evaluation consisted in intra- and interassay precision assessment, determination of sensitivity to unfractionated heparin (UFH) or enoxaparin in spiked samples and to direct oral anticoagulants (DOACs) in patients (n = 43). Method comparison of the 4 PT reagents, factor II, V, VII and X assays was tested on normal (n = 20) and abnormal samples: VKA (n = 47), preoperative (n = 23), liver failure (n = 12) and burned patients (n = 37)., Results: Analytical performance met manufacturers' criteria for all reagents. All PT reagents gave correlation coefficients >0.8 and even >0.9 in many situations. In some VKA samples, differences ≥ 0.5 INR units were found in samples within and above therapeutic ranges. For burned patients, PT correlations were good but with some minimal bias (<5.0%) while factor assays gave very consistent results (R > .8 and mainly >0.9). As expected, poor responsiveness of the PT to DOAC concentrations was observed with all four assays., Conclusion: The STA-NeoPTimal showed comparable performance to ReadiPlasTin, making it suitable for VKA control, detection of factors II, V, VII, X deficiency and assessment of liver disease coagulopathy. However, for patients receiving VKA, some significant differences were observed. We confirmed the inability of the PT assay to detect residual DOAC concentrations. Finally, burned patients results showed that recombinant thromboplastins were less sensitive to factor deficiencies in comparison to extraction thromboplastins., (© 2020 John Wiley & Sons Ltd.)

Introduction: The presence of high fluorescent cells (HF-BF) on the Sysmex XN-1000 hematology analyzers has gained interest regarding the prediction of malignant cells in body fluids, but lacks sensitivity. We aimed to increase this sensitivity by combining HF-BF value, automated results, and clinical information., Methods: We evaluated a new workflow for the management of body fluids in the hematology laboratory, including the HF-BF criterion and clinical information. In two laboratories, 1623 serous fluids were retrospectively analyzed on the XN-1000 BF mode. All samples were morphologically screened for malignant cells. Optimal HF-BF cutoffs were determined to predict their presence. Thereafter, the added value of clinical information was evaluated. Other reflex testing rules (eosinophilic count >5% and presence of the WBC Abnormal Scattergram flag) were also used to refine our workflow., Results: Optimal HF-BF cutoffs in the two hematology centers were 108 and 45 cells/µL, yielding a sensitivity/specificity of 66.7/93.6% and 86.8/66.6% for malignant cell detection. When adding clinical information, sensitivity/specificity evolved to 100.0/68.9% and 100.0%/not determined. Of 104 samples containing malignant cells, 97 had positive clinical information; the remainder had a HF-BF > cutoff., Conclusion: Combining clinical information and HF-BF reached 100% sensitivity for malignant cell detection in body fluid analysis. Lack of robustness of the optimal HF-BF cutoff deserves the use of local cutoffs. Rapid automated results reporting from the XN-1000 BF mode are also feasible in clinical practice. Prospective evaluation of the workflow is needed before its implementation in clinical practice., (© 2020 John Wiley & Sons Ltd.)

Platelet count, indices (mean volume, young-immature platelet fraction) and aggregation are widely used laboratory parameters to investigate primary hemostasis. We performed a systematic, thorough evaluation of the influence of the time-interval since blood draw from 20 healthy individuals and of the anticoagulation of collected blood on such parameters. Blood was anticoagulated with citrate, K 2 -ethylenediaminetetraacetic acid (EDTA) and hirudin and analyzed 5, 30, 60, 120 and 180 min after blood draw. Multiple electrode aggregometry (MEA) was performed with either hirudin (half-diluted with NaCl) or citrate samples (half-diluted with NaCl or CaCl 2 3 mM). Platelet count and indices (Sysmex XN-20) were rather stable over time with EDTA blood. MEA results were lower with citrate blood than with hirudin blood; supplementation with calcium was partially compensatory. MEA results were also lower when performed less than 30 or more than 120 min after blood draw. Platelet clumping, quantitatively estimated with microscope examination of blood smears, was more important in hirudin blood than citrate or EDTA blood and could explain some of the differences observed between preanalytical variables. The results stress once more the importance of preanalytical variables in hemostasis laboratory testing. Decision thresholds based on those tests are only applicable within specific preanalytical conditions.

Standardization, data mining techniques, and comparison to normality are changing the landscape of multiparameter flow cytometry in clinical hematology. On the basis of these principles, a strategy was developed for measurable residual disease (MRD) assessment. Herein, suspicious cell clusters are first identified at diagnosis using a clustering algorithm. Subsequently, automated multidimensional spaces, named "Clouds", are created around these clusters on the basis of density calculations. This step identifies the immunophenotypic pattern of the suspicious cell clusters. Thereafter, using reference samples, the "Abnormality Ratio" (AR) of each Cloud is calculated, and major malignant Clouds are retained, known as "Leukemic Clouds" (L-Clouds). In follow-up samples, MRD is identified when more cells fall into a patient's L-Cloud compared to reference samples (AR concept). This workflow was applied on simulated data and real-life leukemia flow cytometry data. On simulated data, strong patient-dependent positive correlation ( R 2 = 1) was observed between the AR and spiked-in leukemia cells. On real patient data, AR kinetics was in line with the clinical evolution for five out of six patients. In conclusion, we present a convenient flow cytometry data analysis approach for the follow-up of hematological malignancies. Further evaluation and validation on more patient samples and different flow cytometry panels is required before implementation in clinical practice.

Despite the ongoing development of automated hematology analyzers to optimize complete blood count results, platelet count still suffers from pre-analytical or analytical pitfalls, including EDTA-induced pseudothrombocytopenia. Although most of these interferences are widely known, laboratory practices remain highly heterogeneous. In order to harmonize and standardize cellular hematology practices, the French-speaking Cellular Hematology Group (GFHC) wants to focus on interferences that could affect the platelet count and to detail the verification steps with minimal recommendations, taking into account the different technologies employed nowadays. The conclusions of the GFHC presented here met with a "strong professional agreement" and are explained with their rationale to define the course of actions, in case thrombocytopenia or thrombocytosis is detected. They are proposed as minimum recommendations to be used by each specialist in laboratory medicine who remains free to use more restrictive guidelines based on the patient's condition., Competing Interests: The authors declare no conflict of interest.

Keloids are pathologic scars, defined as fibroproliferative diseases resulting from abnormal wound responses, which grow beyond the original wound margins. They develop on specific pro-keloid anatomic sites frequently characterized by high stress states. The initiation and growth mechanisms of keloid are not well-understood. This study relates multimodal investigation of a keloid by using mechanical tests in vivo and imaging techniques. A single case composed of a keloid, the healthy skin surrounding the keloid, and the contralateral healthy skin on the upper arms of a woman has been investigated in extension and suction by using non-invasive devices dedicated to in vivo skin measurement. The thickness and microstructure of these soft tissues have been observed by echography, tomography and confocal microscopy. Displacement fields have been obtained by using digital image correlation. Unlike healthy skin, keloid is not a well-defined multilayer structure: the frontier between epidermis and dermis disappears. The mechanical behavior of keloid is highly different from healthy skin one. The R-parameters have been deduced from suction curves. Physical parameters as tissue extensibility, initial and final tangent moduli have been identified from the stress-strain curves. The extensibility (respectively, initial rigidity) of keloid is highly lower (respectively, higher) than that of healthy skin. To compare the final rigidity of keloid versus healthy skin, further tests have to be performed with higher strain values., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Thrombosis are severe complications of paroxysmal nocturnal hemoglobinuria (PNH), effectively reduced by eculizumab. Extracellular vesicles (EVs) may play a central role. The objective of this study was to assess the procoagulant activity of plasma isolated from PNH patients (treated or not by eculizumab) and to quantify their circulating EVs.We iteratively collected the platelet-free-plasma of 17 PNH patients and 16 matched healthy volunteers, quantified their circulating EVs by flow cytometry and evaluated their procoagulant activity by thrombin generation and STA-Procoag-procoagulant phospholipid (PPL) assays.A significant decrease of EVs from platelets (P = .024) and an increase of the STA-Procoag-PPL clotting time (P = .049) was observed after initiation of eculizumab and up to 11 weeks after. This reduction of prothrombotic biomarkers was not observed with the thrombin generation test due to a lack of sensitivity of this assay. Active hemolysis was observed in 90% of patients and elevated D-dimers in 41% of them. However, no significant difference was observed between patients and control subjects regarding the procoagulant activity, the EVs quantity, or the cellular origin. Lactate dehydrogenase (LDH) levels were lower in eculizumab-treated patients compared to nontreated patients (441 vs 2448 IU/L). D-dimers and LDH decreased after administration of eculizumab (mean decrease of 1307 ng/mL and 4159 IU/L, respectively).These observations suggest a decrease of the phospholipid-dependent procoagulant potential of EVs after eculizumab therapy in PNH patients. TRIAL REGISTRATION:: NUB: B039201214365.

Red blood cell (RBC) concentrates may be stored for up to 42 days before transfusion to a patient. During storage extracellular vesicles (EVs) develop and can be detected in significant amounts in RBC concentrates. The concentration of EVs is affected by component preparation methods, storage solutions, and inter-donor variation. Laboratory investigations have focused on the effect of EVs on in vitro assays of thrombin generation and immune responses. Assays for EVs in RBC concentrates are not standardized. The aims of this review are to describe the factors that determine the presence of erythrocyte-EVs in RBC concentrates, the current techniques used to characterize them, and the potential role of EV analysis as a quality control maker for RBC storage., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Despite its considerable morbidity and mortality, paroxysmal nocturnal haemoglobinuria (PNH) is still underdiagnosed. Patients with PNH can suffer from cardiovascular, gastrointestinal, neurological or haematological symptoms and refer to several specialists. The aim of this paper is to review the diagnosis and the management of PNH patients, with the primary focus on identifying high-risk groups. Additionally, the implementation and prognostic value of the defined high-risk groups will be commented on and the management of PNH patients is discussed from a Belgian perspective. Finally, based on the available data, recommendations are provided. Eculizumab is a potent C5 complement inhibitor and reduces intravascular haemolysis and thrombosis in PNH patients and improves their quality of life. As thrombosis is the main cause of death in PNH patients, identifying high-risk PNH patients in need of therapy is essential. Currently, novel complement inhibitors are in development and the first data seem promising. Another challenge in PNH is to identify new markers to assess the thrombotic risk to achieve a better risk-based prophylactic anti-thrombotic management. Finally, because of the low prevalence of the disease, PNH patients should be included in the prospective PNH registry, which will offer new insights on the natural course of the disease and the impact of treatment of PNH., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

D-dimer is a soluble fibrin degradation product deriving from the plasmin-mediated degradation of cross-linked fibrin. D-dimer can hence be considered a biomarker of activation of coagulation and fibrinolysis, and it is routinely used for ruling out venous thromboembolism (VTE). D-dimer is increasingly used to assess the risk of VTE recurrence and to help define the optimal duration of anticoagulation treatment in patients with VTE, for diagnosing disseminated intravascular coagulation, and for screening medical patients at increased risk of VTE. This review is aimed at (1) revising the definition of D-dimer; (2) discussing preanalytical variables affecting the measurement of D-dimer; (3) reviewing and comparing assay performance and some postanalytical variables (e.g. different units and age-adjusted cutoffs); and (4) discussing the use of D-dimer measurement across different clinical settings.

Introduction:  Betrixaban is a novel direct oral factor Xa inhibitor approved by the Food and Drug Administration for prophylaxis of venous thromboembolism in adult patients hospitalized for an acute illness at risk for thromboembolic complications. Assessment of the anti-coagulant effect of betrixaban may be useful in some situations. Also, clinicians need to know how routine coagulation assays are influenced., Objective:  The aim of this study is to determine which coagulation assay(s) should be used to assess the impact of betrixaban on haemostasis and provide laboratory guidance for their interpretation., Materials and Methods:  Betrixaban was spiked at final concentrations ranging from 0 to 250 ng/mL in platelet-poor plasma. Different reagents from several manufacturers were tested and the impact of betrixaban on pro-thrombin time (PT), activated partial thromboplastin time (aPTT), dilute Russel viper venom time (dRVV-T), chromogenic anti-Xa assays, thrombin generation assay (TGA), and a large panel of haemostasis diagnostic tests has been assessed., Results:  A concentration-dependent prolongation of aPTT, PT and dRVV-T is observed. The sensitivity mainly depends on the reagent. Chromogenic anti-Xa assays show high sensitivity depending on the reagent and/or the methodology. These assays applicable for other direct factor Xa inhibitors have to be adapted to obtain a relevant range of measurement. TGA may also be attractive to assess the anti-coagulant activity of betrixaban., Conclusion:  Adapted chromogenic anti-Xa assays are the most appropriate assays to estimate the concentration of betrixaban. Betrixaban significantly affects several haemostasis diagnostic tests and this needs to be taken into consideration when requesting and interpreting such tests., Competing Interests: Among the authors, J. Douxfils is CEO and founder of QUALIblood s.a. and reports personal fees from Stago and Daiichi-Sankyo, outside the submitted work. F. Mullier reports institutional fees from Stago, Werfen, Nodia, Sysmex and Bayer. He also reports speaker fees from Boehringer Ingelheim, Bayer Healthcare and Bristol-Myers Squibb-Pfizer, all outside the submitted work. Other authors have no conflicts of interest to disclose., (Georg Thieme Verlag KG Stuttgart · New York.)

The impact of direct oral anticoagulants (DOACs) on laboratory assays used for thrombophilia testing (e.g., antithrombin, protein S, protein C, lupus anticoagulant and activated protein-C resistance) is a well-known issue and may cause false-positive and -negative results. Therefore, the correct interpretation of tests that are performed in patients taking DOACs is mandatory to prevent misclassification and the subsequent clinical consequences. We aimed at evaluating the efficiency of a new and simple procedure (DOAC-Stop®; Haematex Research, Hornsby, Australia) to overcome the effect of all DOACs in real-life settings and to assess the percentage of erroneous results due to the presence of DOACs on thrombophilia screening tests. For this purpose, 135 DOAC-treated patients (38 apixaban, 40 dabigatran, 15 edoxaban, and 42 rivaroxaban) and 20 control patients were enrolled. A significant drop in apixaban, dabigatran, edoxaban, and rivaroxaban plasma concentrations following the DOAC-Stop® treatment was observed (74.8-8.2 ng/mL [ p  < 0.0001], 95.9-4.7 ng/mL [ p  < 0.0001], 102.1-8.8 ng/mL [ p  = 0.001], and 111.3-7.0 ng/mL [ p  < 0.0001], respectively). The DOAC-Stop® treatment was mostly effective to overcome the effect of DOACs on PTT-LA, dilute Russell's viper venom time (dRVVT) screen, and dRVVT confirm tests. Using our procedures, false-positive results due to DOACs were observed only with lupus anticoagulant tests (up to 75%) and fell to zero after the DOAC-Stop® procedure, regardless of the DOAC considered. In conclusion, the DOAC-Stop® adsorbent procedure appeared to be an effective and simple way to overcome the interference of DOAC on coagulation tests and should facilitate the interpretation of thrombophilia screening tests in patients taking DOACs.

Background: Thrombotic effects are possible complications of red blood cell transfusion. The generation and accumulation of procoagulant red blood cell extracellular vesicles during storage may play an important role in these thrombotic effects. The objective of this study was to assess the value of a simple phospholipid-dependent clot-based assay (STA ® -Procoag-PPL) to estimate the procoagulant activity of stored red blood cells and changes in this activity during storage of the blood component., Materials and Methods: Extracellular vesicles from 12 red blood cell concentrates were isolated at 13 storage time-points and characterised by quantitative and functional methods: the degree of haemolysis (direct spectrophotometry), the quantification and determination of cellular origin (flow cytometry) and the procoagulant activity (thrombin generation and STA ® -Procoag-PPL assays) were assessed., Results: The mean clotting time of extracellular vesicles isolated from red blood cell concentrates decreased from 117.2±3.6 sec on the day of collection to 33.8±1.3 sec at the end of the storage period. This illustrates the phospholipid-dependent procoagulant activity of these extracellular vesicles, as confirmed by thrombin generation. Results of the peak of thrombin and the STA ® -Procoag-PPL were well correlated (partial r=-0.41. p<0.001). In parallel, an exponential increase of the number of red blood cell-derived extracellular vesicles from 1,779/μL to 218,451/μL was observed., Discussion: The STA ® -Procoag-PPL is a potentially useful technique for assessing the procoagulant activity of a red blood cell concentrate.

Introduction: Estimation of residual rivaroxaban plasma concentrations may be requested before invasive procedures and some patients at high thromboembolic risk will have a bridging therapy with heparins when rivaroxaban is interrupted., Objective: The objective of this study was to assess the performance of the STA-Liquid Anti-Xa assay (STA LAX) and the low and normal procedures of the Biophen Direct Factor Xa Inhibitors (DiXaI) assay, in patients with and without bridging with low-molecular-weight heparins (LMWHs)., Materials and Methods: Seventy-nine blood samples were collected from 77 patients on rivaroxaban at C TROUGH or before an invasive procedure. Rivaroxaban plasma concentrations were estimated using Biophen DiXaI, Biophen DiXaI LOW, and STA LAX and compared to liquid chromatography coupled with mass spectrometry (LC-MS/MS) measurements. Stratifications were performed according to heparin bridging., Results: The Biophen DiXaI LOW and STA LAX showed better correlation with LC-MS/MS measurements than Biophen DiXaI in patients not bridged with LMWH (R: 0.97, 0.96, and 0.91, respectively). However, the performance of Biophen DiXaI LOW and STA LAX decreased when residual LMWH activity was present (R: 0.18 and 0.19 respectively) demonstrating that these tests are not specific to rivaroxaban., Conclusion: In patients not bridged with LMWH, we suggest to use the Biophen DiXaI LOW and STA LAX for the estimation of rivaroxaban concentrations <50 ng/mL. These results should be confirmed on a larger cohort of patients. Patients bridged with LMWH have inaccurate estimates of low levels of rivaroxaban and the 3 assays studied should not be used to estimate if it is safe to perform a procedure.

Neutropenia is one of the main criteria for a blood smear review. The objective of this study was to compare the thresholds proposed by the international consensus group for hematology review (1.0 10 9 /L) and the French speaking Group for Cellular Haematology (1.5 10 9 /L) in terms of the number of useless smears. We collected 112,097 analyzed samples from four laboratories equipped with XN instruments (Sysmex, Kobe, Japan) during early 2016. The only exclusion criterion was a leucocyte count below 0.5 10 9 /L. In the absence of abnormal cells and/or morphology suggesting haematological disease, samples were classified as 'negative for morphology' and the differential from the XN-10 was reported. These smear procedures were considered as uninformative. Some 2202 samples met the criterion for neutropenia (<1.5 10 9 /L) for slide review representing 1.96% of the total. These included 1031 with neutropenia alone and 1171 neutropenia plus other abnormalities. Of the 1031 with neutropenia alone, 886 had a neutrophil count between 1.0 10 9 /L and 1.5 10 9 /L. The smear was uninformative for all of these samples. In conclusion, microscopic examination of a blood smear provided very limited information in cases of neutropenia without other abnormalities.

Introduction: 3D printing seems to have more and more applications in maxillofacial surgery (MFS), particularly since the release on the market of general use 3D printers several years ago. The aim of our study was to answer 4 questions: 1. Who uses 3D printing in MFS and is it routine or not? 2. What are the main clinical indications for 3D printing in MFS and what are the kinds of objects that are used? 3. Are these objects printed by an official medical device (MD) manufacturer or made directly within the department or the lab? 4. What are the advantages and drawbacks?, Methodology: Two bibliographic researches were conducted on January the 1st, 2017 in PubMed, without time limitation, using "maxillofacial surgery" AND "3D printing" for the first and for the second "maxillofacial surgery" AND "computer-aided design" AND "computer-aided manufacturing" as keywords. Articles in English or French dealing with human clinical use of 3D printing were selected. Publication date, nationality of the authors, number of patients treated, clinical indication(s), type of printed object(s), type of printing (lab/hospital-made or professional/industry) and advantages/drawbacks were recorded., Results: Two hundred and ninety-seven articles from 35 countries met the criteria. The most represented country was the People's Republic of China (16% of the articles). A total of 2889 patients (10 per article on average) benefited from 3D printed objects. The most frequent clinical indications were dental implant surgery and mandibular reconstruction. The most frequently printed objects were surgical guides and anatomic models. Forty-five percent of the prints were professional. The main advantages were improvement in precision and reduction of surgical time. The main disadvantages were the cost of the objects and the manufacturing period when printed by the industry., Discussion: The arrival on the market of low-cost printers has increased the use of 3D printing in MFS. Anatomic models are not considered to be MDs and do not have to follow any regulation. Nowadays, they are easily printed with low-cost printers. They allow for better preoperative planning and training for the procedures and for pre-shaping of plates. Occlusal splints and surgical guides are intended for the smooth transfer of planning to the operating room. They are considered to be MDs and even if they are easy to print, they have to follow the regulations applying to MDs. Patient specific implants (custom-made plates and skeletal reconstruction modules) are much more demanding objects and their manufacturing remains nowadays in the hands of the industry. The main limitation of in-hospital 3D printing is the restrictive regulations applying to MDs. The main limitations of professional 3D printing are the cost and the lead time. 3D printed objects are nowadays easily available in MFS. However, they will never replace a surgeon's skill and should only be considered as useful tools., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Background: The dilute Russell's viper venom time (dRVVT) has been suggested for the assessment of the intensity of anticoagulation of all direct oral anticoagulants (DOACs). This study aimed to compare the performance of an optimized liquid-stable dRVVT-based DOAC assay (DRVV-DOAC) on clinical samples before and after mixing these with normal pooled plasma (NPP)., Methods: Forty-one apixaban, 25 dabigatran, 56 rivaroxaban and 49 vitamin K antagonists (VKAs) plasma samples were included for retrospective analysis. Plasma DOAC concentrations were determined by liquid chromatography coupled with tandem mass-spectrometry. INR was determined for all VKA samples. DRVV-DOAC was performed with an original ready-to-use reagent (Haematex Research ™ ) where plasma samples were tested neat and in a 1:1 mix with NPP., Results: Plasma concentrations ranged from 1 to 406ng/ml for apixaban, 0 to 386ng/ml for dabigatran and 0 to 719ng/ml for rivaroxaban. INR ranged from 2.2 to 6.1. DRVV-DOAC correlated well with plasma concentrations (r 2 =0.70, 0.94, 0.63 (non-mixed procedure) and 0.77, 0.97, 0.86 (mixed procedure) for apixaban, dabigatran and rivaroxaban, respectively). DRVV-DOAC measurements in the normal range ruled out dabigatran and rivaroxaban concentrations above 30 and 50ng/ml, but performance was lower for apixaban. DRVV-DOAC was sensitive to VKA samples but poorly reflected INR values. When VKA samples were mixed with NPP, DRVV-DOAC measurements decreased to values close to baseline clotting time., Conclusions: DRVV-DOAC is a quick method which showed increased sensitivity compared with other phospholipid-rich dRVVT reagents already investigated. Mixing samples with NPP improved the specificity but reduced sensitivity, especially for apixaban., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Introduction: Paroxysmal nocturnal hemoglobinuria (PNH) is a disease characterized by the susceptibility of blood cells to attack by the complement system, inducing extracellular vesicle (EV) production. Thromboembolism is the leading cause of death in this condition. Eculizumab, a humanized monoclonal antibody which inhibits the C5 protein of the complement, reduces the thrombotic risk in PNH., Materials and Method: We conducted a pilot, prospective, open-label, longitudinal clinical study with six PNH patients treated with eculizumab. The aim was to measure, by flow cytometry, the EVs' production in the patients' platelet-free plasma (PFP) before and during the treatment. We also assessed the procoagulant activity in PFP using STA®-Procoag-PPL and thrombin generation assays (TGA). A high-sensitive version of TGA was also used to study the procoagulant profile induced by the EVs using EVs pelleted from PFP., Results: We observed a decrease in platelet EV count with eculizumab treatment (p<0.05). STA®-Procoag-PPL assay showed a decrease of the procoagulant profile induced by procoagulant phospholipids (PL) during treatment. These results were not confirmed by TGA on PFP, due to a lack of sensitivity. Thus, we used a high-sensitive version of TGA that enabled us to observe variation in the procoagulant profile induced by the EVs with eculizumab (p<0.05)., Conclusions: Eculizumab has an impact on the extent of EV production and on the procoagulant profile induced by the procoagulant PL and the EVs. One factor in the antithrombotic action of eculizumab is its ability to decrease EV production and the procoagulant profile induced by PL and EVs., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Introduction: The Belgian national External Quality Assessment Scheme performed a survey to assess the effect of the direct oral anticoagulant apixaban on the coagulation assays prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen and antithrombin as performed with a large number of reagent/instrument combinations., Methods: Four lyophilized plasma samples spiked with apixaban (0, 41, 94 and 225 ng/mL) were sent to the 195 Belgian and Luxembourg clinical laboratories performing coagulation testing., Results: PT and aPTT were barely influenced at the concentrations tested. At 225 ng/mL apixaban, PT and aPTT clotting times were only 1.15 times longer than at 0 ng/mL. Among PT reagents, RecombiPlasTin 2G ® showed a slightly higher sensitivity with 225 ng/mL apixaban prolonging the PT clotting time 1.3-fold. Among aPTT reagents, there was no appreciable difference in sensitivity. Fibrinogen results were unaffected by the presence of apixaban, but antithrombin activity was considerably overestimated when measured with a FXa-based assay. At 225 ng/mL apixaban, the median percentage increase in antithrombin level was 31% when measured with the Liquid Antithrombin ® reagent and 44% with the Innovance Antithrombin ® reagent., Conclusion: Our data provide clinical laboratories with useful information on the impact of apixaban on their routine coagulation assays., (© 2017 John Wiley & Sons Ltd.)

In 2014, we moved from XE-2100 with Standard SIS rules to XN-9000 with GFHC recommendations for slide review. The aim of our study was to evaluate the potential impact of the new Sysmex ® automation with implementation of GFHC rules on our review rate, turnaround time (TAT), workload and on CD34+ stem cells enumeration. We conducted a retrospective observational study from September 2013 through August 2014, in CHU Dinant Godinne UCL Namur. With the GFHC recommendations and the new Sysmex ® automation, we significantly reduced our review rate by nearly 30% considering all units (35.8% vs 25.9%), and up to 73% when excluding oncology haematology department (17.5% vs 4.7%). We also noticed significantly shorter TAT for CBC measurement (median for routine samples: 76.4 vs 56.8 minutes, p < 0.0001; urgent samples: 18.9 vs 15.2 minutes, p = 0.023), slide review (median: 54.9 vs 36.4 minutes, p < 0.0001) and CD34+ enumeration performed on peripheral blood samples (p < 0.001) and on apheresis samples (p = 0.026). In conclusion, GFHC recommendations implemented on the new Sysmex ® XN-9000 resulted in a significant reduction in review rate and in TAT. This is particularly of interest for the clinicians with subsequent potential faster patient management.

Direct oral anticoagulants (DOACs) have been licensed worldwide for several years for various indications. Each year, 10-15% of patients on oral anticoagulants will undergo an invasive procedure and expert groups have issued several guidelines on perioperative management in such situations. The perioperative guidelines have undergone numerous updates as clinical experience of emergency management has increased and perioperative studies including measurement of residual anticoagulant levels have been published. The high inter-patient variability of DOAC plasma levels has challenged the traditional recommendation that perioperative DOAC interruption should be based only on the elimination half-life of DOACs, especially before invasive procedures carrying a high risk of bleeding. Furthermore, recent publications have highlighted the potential danger of heparin bridging use when DOACs are stopped before an invasive procedure. As antidotes are progressively becoming available to manage severe bleeding or urgent procedures in patients on DOACs, accurate laboratory tests have become the standard to guide their administration and their actions need to be well understood by clinicians. This review aims to provide a systematic approach to managing patients on DOACs, based on recent updates of various perioperative guidance, and highlighting the advantages and limits of recommendations based on pharmacokinetic properties and laboratory tests.

Introduction: Wisdom teeth extraction is a common procedure, generally considered as safe by patients. However, complications are possible, especially periodontal ones. The aim of this study was to evaluate the frequency and the consequences of periodontal complications at the level the 2nd molars after extraction of the wisdom teeth., Material and Methods: A single-center retrospective observational multi-operator study was conducted at the university hospital of Besançon - France. The files of all the adult patients who underwent extraction of four impacted wisdom teeth by mean of a standardized surgical technique between November 2012 and November 2014 and who could be followed 1 year postoperatively at least and that precisely mentioned the periodontal status of the surgical sites were included. Postoperative complications, gingival and plaque indexes according to Loë and Silness, periodontal attachment level and periodontal second molar probing were recorded. The main judgment criterion was the occurrence of a periodontal complication in the second molar areas., Results: The files of 20 patients (15 women - 5 men), operated on by five different surgeons, met the inclusion criteria. Two patients suffered from dry socket at one of the avulsion sites. No patient had a gingival or plaque index greater than 2. No gingival recession or periodontal pocket over 4mm was found., Discussion: Extraction of impacted third molars in young healthy adults didn't have any impact on the second molars periodontal environment in our study. Literature suggests that surgical technique greatly influences the occurrence and the extent of periodontal sequelae., (Copyright © 2017. Published by Elsevier Masson SAS.)

Haemostatic complication is common for patients with hematologic malignancies. Recent studies suggest that the procoagulant activity (PCA) of extracellular vesicles (EV) may play a major role in venous thromboembolism and disseminated intravascular coagulation (DIC) in acute leukaemia. To study the impact of EVs from leukaemic patients on thrombin generation and to assess EV-PCA as a potential biomarker for thrombotic complications in patients with acute leukaemia. Blood samples from a cohort of patients with newly diagnosed acute leukaemia were obtained before treatment (D-0), 3 and 7 days after treatment (D-3 and D-7). Extracellular vesicles were isolated and concentrated by ultracentrifugation. EV-PCA was assessed by thrombin generation assay, and EV-associated tissue factor activity was measured using a commercial bio-immunoassay (Zymuphen MP-TF®). Of the 53 patients, 6 had increased EV-PCA at D-0 and 4 had a thrombotic event. Patients without thrombotic events (n = 47) had no elevated EV-PCA. One patient had increased EVs with procoagulant activity at D-3 and developed a DIC at D-5. This patient had no increased EVs-related tissue factor activity from D-0 to D-7 (<2 pg/ml). Eight patients had increased EVs with tissue factor activity (>2 pg/ml), of these, four had a thrombosis and two had haemorrhages. Procoagulant activity of extracellular vesicles could have a predictive value in excluding the risk of thrombotic events. Our findings also suggest a possible association between thrombotic events and EV-PCA.

Ensuring quality has become a daily requirement in laboratories. In haemostasis, even more than in other disciplines of biology, quality is determined by a pre-analytical step that encompasses all procedures, starting with the formulation of the medical question, and includes patient preparation, sample collection, handling, transportation, processing, and storage until time of analysis. This step, based on a variety of manual activities, is the most vulnerable part of the total testing process and is a major component of the reliability and validity of results in haemostasis and constitutes the most important source of erroneous or un-interpretable results. Pre-analytical errors may occur throughout the testing process and arise from unsuitable, inappropriate or wrongly handled procedures. Problems may arise during the collection of blood specimens such as misidentification of the sample, use of inadequate devices or needles, incorrect order of draw, prolonged tourniquet placing, unsuccessful attempts to locate the vein, incorrect use of additive tubes, collection of unsuitable samples for quality or quantity, inappropriate mixing of a sample, etc. Some factors can alter the result of a sample constituent after collection during transportation, preparation and storage. Laboratory errors can often have serious adverse consequences. Lack of standardized procedures for sample collection accounts for most of the errors encountered within the total testing process. They can also have clinical consequences as well as a significant impact on patient care, especially those related to specialized tests as these are often considered as "diagnostic". Controlling pre-analytical variables is critical since this has a direct influence on the quality of results and on their clinical reliability. The accurate standardization of the pre-analytical phase is of pivotal importance for achieving reliable results of coagulation tests and should reduce the side effects of the influence factors. This review is a summary of the most important recommendations regarding the importance of pre-analytical factors for coagulation testing and should be a tool to increase awareness about the importance of pre-analytical factors for coagulation testing.

Traditional anticoagulant agents such as unfractionated heparin (UFH), low molecular weight heparins (LMWHs), fondaparinux, danaparoid and bivalirudine are used in the prevention and treatment of thromboembolic diseases. However, these agents have limitations: their constraining parenteral route of administration and the need for regular coagulation monitoring for HNF. The LMWHs, with their more predictable anticoagulant response, don't require a systematic monitoring. The usefulness of LMWHs monitoring in several clinical situations such as pregnancy, obesity and renal insufficiency is a matter of debate. Indeed, there is no agreement between French and American recommendations on this question. Others aspects are also controversial: the measure of trough anti-Xa activity during pregnancy and the optimal monitoring of LMWHs for patients with antithrombin deficiency (hepatic disease, new-borns). Different tests are available to ensure the monitoring of these drugs, we will see in this review their principle, their advantages and inconvenients. The management of heparin induced thrombocytopenia also needs parenteral anticoagulants: danaparoïd, bivalirudine or argatroban. The modalities of their monitoring are relatively unknown and are presented. Furthermore, platelet monitoring is capital. This article aims to provide guidance about laboratory testing of classic parenteral anticoagulants.

The French-Speaking Cellular Haematology Group (GFHC) recently published criteria for microscopic analysis of a blood smears when a hemogram is requested. In order to evaluate and improve these recommendations using an XN (Sysmex) analyzer, we assessed 31,836 samples categorized into two sub-groups of patients either receiving or not receiving care in the clinical hematology/oncology departments of two university hospitals. By combining the manufacturer's recommendations and the GFHC recommendations, 21.3% of samples had a positive review flag in phase 1 of our study (17,991 samples). In phase 2 (13,845 samples), increasing the immature granulocytes (IG) percentage from 5-10% as a review trigger threshold, and ignoring slides with isolated flags 'PLT HIGH' (thrombocytosis) or 'MCV LOW' (microcytosis) or 'Blast/Abn Lymph and Atypical Lymph' (blast cells/abnormal lymphocytes and atypical lymphocytes) (in the absence of abnormal cells on a previous blood smear within 72 h), enabled us to significantly reduce the number of slides reviewed from 21.3-15.0% (p < 0.0001), without loss of clinical value. This decrease occurred in both sub-groups (hematology 48.7-38.0%, non-hematology 18.3-11.7%, p < 0.0001). In conclusion, the application of the GFHC criteria adapted to XN analyzers has enabled us to optimize the hematology laboratory processes, and thus reduce the production costs and the turnaround time of hemogram results.

Introduction: Craniosynostoses affecting the forehead sutures can not only cause brain damage, but can also have an esthetic impact, because of the associated orbito-naso-frontal deformations. Reshaping the orbito-naso-frontal bandeau (ONFB) is difficult to appreciate perioperatively and should ideally be customized to each child. The aim of this study was to develop a template to guide the surgeon preoperatively towards an ideal customized remodelling of the ONFB., Materials and Methods: A previous study conducted on computed tomography scans obtained from healthy children allowed us to conclude that the whole ONFB shape could be accurately described just by the distance measured between the fronto-zygomatic sutures (FZD), independently of age and gender. Our customizable template relies on this measurement., Results: A re-usable template, built around three supports adjustable to a wide range of FZD, was designed using the CAD 3D Rhinoceros ® software and machined in stainless steel 316L. The prototype was used for three children with good preliminary results., Discussion and Conclusion: The use of a customizable surgical template allows the surgeon to perform accurate and ideal perioperative remodeling of the ONFB in children suffering from craniosynostosis affecting the forehead sutures. Our prototype is currently the only one to be adjustable according to the FZD. The utility of this device will be assessed in a future prospective clinical study., (Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Introduction: Arthocentesis of the temporomandibular joint combined with intra-articular washout and, more recently, intra-articular injection of pharmacological agents has been developed from the 1990s and is nowadays extensively in use for the treatment of temporomandibular dysfunctions (TMDs). The goal of our work was to answer 3 questions: 1. Is intra-articular washout effective for the treatment of TMDs ? 2. What kind of pharmacological agents may nowadays be injected in addition to washout and are these injections useful ? 3. What is the place of these treatments in the treatment strategies of TMDs ?, Material and Methods: A bibliographic research has been carried out in the PubMed database using following keywords arthrocentesis, temporomandibular joint. The 27 articles published between 1991 and 2016, indicating patient's inclusion criterions and objectively evaluating the clinical results (mouth opening, intra-articular noises, pain) were selected. Pharmacological agents were noticed when used., Results: 1. All authors concluded to the efficacy of intra-articular washout. No prognostic factor for arthrocentesis efficacy could be identified. 2. Main pharmacological agents used were steroids, hyaluronic acid, morphine-based drugs and platelet rich plasma. Superiority of ith-injection protocols failed to win unanimous support. All authors who compared with- and without-injection protocols concluded to the superiority of with-injection protocols, whatever the agent., Discussion: Numerous studies have proven the efficacy of intra-articular washout for the treatment of TMDs resistant to noninvasive treatments. The advantage of any kind of pharmacological agent is not clear. Mechanisms of action are not all elucidated. No pharmacological agent showed any superiority over another. Study methodologies are often defective: imprecise inclusion criterions, short follow-up, confounding variables not taken into account, few comparison between pharmacological agents., (Copyright © 2016 Elsevier Masson SAS. All rights reserved.)

Assessment of plasma concentration/effect of edoxaban may be useful in some situations. Also, clinicians need to know how routine coagulation assays are influenced. It was our aim to determine coagulation tests useful for the assessment of edoxaban's pharmacodynamics and provide recommendations for the interpretation of haemostasis diagnostic tests. Edoxaban was spiked at concentrations ranging from 0 to 1,000 ng/ml in platelet-poor plasma which covers the on-therapy range (from ± 25 ng/ml at Ctrough to ± 170 ng/ml at Cmax). aPTT, PT, dRVVT, chromogenic anti-Xa assays, TGA and a large panel of haemostasis diagnostic tests were performed using several reagents. A concentration-dependent prolongation of aPTT, PT and dRVVT was observed. The effect was dependent on the reagents. FXa chromogenic assays showed high sensitivity and a linear correlation depending on the methodology. TGA may be useful to assess the pharmacodynamics of edoxaban but its turnaround time and the lack of standardisation are limitations. Edoxaban impairs the assessment of lupus anticoagulant, protein S (clotting method), APC-R, antithrombin (FXa-based assay) and measurement of clotting factor activity. Immunological assays and assays acting below the FXa are not influenced by edoxaban. In conclusion, some PT reagents could be used to estimate edoxaban activity. Chromogenic anti-Xa assays are required to assess the plasma concentration. TGA may be useful but requires standardisation. In case of thrombophilia or in the exploration of a haemorrhagic event, immunological assays should be recommended, when applicable. Standardisation of the time between the last intake and the sampling is mandatory to provide a proper assessment of the result.

Facing coagulation disorders after acute trauma., Problems/objectives: Trauma is the leading cause of mortality for persons between one and 44 years of age, essentially due to bleeding complications., Methodology: We screened the PubMed, Scopus and Cochrane Library databases, using specific keywords. Only publications in English were considered., Main Results: The pathophysiology of trauma-induced coagulopathy (TIC) is complex and includes the classic "lethal triad" (i.e., haemodilution, acidosis, hypothermia) but may also include activation of protein C, endothelial and platelet dysfunction, and fibrinogen depletion. The time between trauma and treatment of the resultant massive bleeding should be as short as possible using techniques for rapid control of bleeding and avoiding aggravating factors (hypothermia, metabolic acidosis and hypocalcaemia). If given within three hours of injury, tranexamic acid (TXA) reduces all causes of mortality in trauma patients and reduces transfusion requirements. In a bleeding patient, crystalloids are preferred to colloids and the ratio of fresh frozen plasma to packed red blood cells should be at least 1:2. Damage control surgery (DCS) should be considered for patients who present with, or are at risk for developing, the "lethal triad", multiple life-threatening injuries or shock, and in mass casualty situations. DCS can also aid in the evaluation of the extent of tissue injuries and the control of haemorrhage and infection. Finally, there is currently no evidence of the added value of laboratory assays in the management of TIC., Conclusions: TIC appears quickly after trauma and should be anticipated and detected as soon as possible. TXA plays a central role in the management of such patients. Each institution should establish a local algorithm for the management of bleeding patients.

Introduction: Craniosynostoses are cranio-facial malformations affecting about 1/2100 newborns in France. The involvement of anterior sutures (coronal and metopic) leads to orbito-frontal deformities. The treatment calls upon surgery the goal being, on an esthetic point of view, to restore a normal anatomy. The purpose of our work was to establish if some facial and/or frontal measures easy to perform on a CT are correlated to the global shape of the normal orbito-naso-frontal bandeau (ONFB)., Material and Method: Cranial CTs of 123 consecutive non-malformed children aged between 4 and 12 months were selected in the database of Department of Radiology of the University Hospital of Besançon - France. The CTs were all relocated by rigid transformation in an orthonormal coordinate system. On each of the 123 CTs, 21 reproducible measures representative of the global shape of the ONFB were made. Statistical analyses of these measures were achieved, considering age and gender, in order to determine the correlation between each measure and the ONFB shape., Results: The only measure statistically correlated to the ONFB shape was the distance between the fronto-zygomatic sutures (FZD). The FZD was independent from age (in an interval of 4 months) and from gender. The 20 other measures did not show any correlation with age or gender., Discussion: The FZD allows in itself to determine the ONFB global shape. This measure, easily available on a CT, can help the surgeon to perform a customized reshaping of the ONFB. The development of a surgical template using this measure is ongoing., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Objectives: Paroxysmal nocturnal hemoglobinuria (PNH) is currently diagnosed by flow cytometry; although highly sensitive, its interpretation and reporting appear as critical as its technique. Thus, we developed a quality control scheme for the French-speaking region based on the international recommendations for PNH screening., Methods: After a topical workshop, we proposed a 1-year, two-step survey program to any volunteering French-speaking clinical laboratory. The first survey consisted of sending raw data files to evaluate gating and the interpretation strategy of each center. The second stipulated sending fresh whole-blood samples to evaluate the whole process and its practice., Results: Forty-nine participants from voluntary centers returned results for each of the two successive surveys. On virtual survey, 27% reported false-positive PNH created by immature granulocytes, whereas the minor PNH clone was not detected by 9%. On fresh survey, 63% of centers used at least the same six-color combination (CD24, CD14, CD33, CD15, CD45, and fluorescent aerolysin), and nearly 70% of participants were able to perform a sensitivity test less than 0.1% on neutrophils. All participants detected the major PNH clone, yet 16% returned false-positive results for the non-PNH clone case., Conclusions: We succeeded in rallying numerous French-speaking clinical laboratories for both surveys and in harmonizing the technical practice by highlighting common pitfalls., (Copyright© by the American Society for Clinical Pathology.)

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired disorder of the hematopoietic stem cell that makes blood cells more sensitive to the action of complement. Patients experience intravascular hemolysis, smooth muscle dystonia, renal failure, arterial and pulmonary hypertension, recurrent infectious diseases and an increased risk of notably dreadful thrombotic complications. The diagnosis is made by flow cytometry. Efforts have been recently performed to improve the sensitivity and the standardization of this technique. PNH is frequently associated with aplastic anemia or low-risk myelodysplasia and may be asymptomatic. Management of the classical form of PNH has been dramatically revolutionized by the development of eculizumab, which brings benefits in terms of hemolysis, quality of life, renal function, thrombotic risk, and life expectancy. Prophylaxis and treatment of arterial and venous thrombosis currently remain a challenge in PNH., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Introduction: When occurring in childhood, temporomandibular ankylosis joint is responsible for complex maxillofacial deformities, including mandibular growth deficiency. We present a case of temporomandibular joint ankylosis associated with severe mandibular asymmetry treated by mandibular bone distraction performed under computer assistance., Observation: A 27-year-old patient presented with a severe facial asymmetry consisting in hypoplasia of the left hemi-mandible and maxilla. Mouth opening was non-existent. The CT-scan showed a left temporomandibular ankylosis. A left mandibular distraction was decided. The distraction characteristics (choice and positioning of the distractor, axis and amount of distraction) were determined preoperatively on the 3D CT-scan. The planning has been transferred to a navigation console (Kolibri®, Brainlab®). A combined intraoral and cutaneous was performed. Navigation allowed for an appropriate placement of the osteotomy line and fixation of the distractor. Distraction was started at the 5th postoperative day at the rate of 1mm per day and lasted 25 days without complication., Discussion: 3D planning allows for better indication setting, better preparation of the procedure, reducing complications and operative time. It may help as an educational tool for young surgeons and for a better understanding from the patient. Navigation is an accurate method for the transfer of the planning in the operation room., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Non-VKA oral anticoagulants (NOACs), thanks to their ease of use and their similar or superior safety/efficacy profiles versus warfarin, have now widely reached the lucrative market of anticoagulation. However, while the marketing authorization holders always claim, in a quite unclear way that no monitoring is required, accumulative evidence and cases of major bleeding have been described in the literature and reported by spontaneous reporting systems at the regulator's level. These compounds are usually given at fixed doses without routine coagulation monitoring. However, new data suggests that an assessment of the response at the individual level could improve the benefit-risk ratio of, at least dabigatran. Therefore, in certain patient populations, i.e. acute or chronic renal impairment or multiple drug interactions, measurement of drug exposure may be useful to ensure an optimal treatment response. More specific circumstances such as patients experiencing a haemorrhagic or thromboembolic event during the treatment duration, patients who require urgent surgery or an invasive procedure, or patient with a suspected overdose could benefit from such a measurement. This article aims at providing guidance on how to best estimate the intensity of anticoagulation using laboratory assays in daily practice.

Background: Dilute Russell Viper Venom Time (DRVV-T) might be useful in urgent settings for screening patients on Non-VKA Oral Anticoagulants (NOACs)., Aim: To compare the accuracy of DRVV-T with gold standard assays for the assessment of pharmacodynamics of dabigatran, rivaroxaban and vitamin K antagonist (VKA) in plasma samples from patients., Methods: Sixty rivaroxaban, 48 dabigatran and 50 VKA samples from patients were included. DRVV-T was performed in all groups using STA®-Staclot®DRVV-Screen and -Confirm. For NOACs, PT and aPTT were performed using different reagents while plasma drug concentrations were measured by liquid mass-spectrometry (LC-MS/MS). For VKA, INR was performed using RecombiPlasTin 2G®., Results: For NOACs, correlations between calibrated STA®-Staclot®DRVV-Confirm and LC-MS/MS (rs=0.88 and 0.97 for rivaroxaban and dabigatran, respectively) were higher than the ones obtained with STA®-Staclot®DRVV-Screen (rs=0.87 and 0.91), PT (rs=0.83 to 0.86) or aPTT (rs=0.84 to 0.89). Bland Altman analyses showed that calibrated DRVV-T methods tend to overestimate plasma concentrations of NOACs. ROC curves revealed that cut-off to exclude supra-therapeutic levels at Ctrough (i.e. 200ng/mL) are different for dabigatran and rivaroxaban. Neither STA®-Staclot®DRVV-Screen nor -Confirm correlated sufficiently with the intensity of VKA therapy (rs=0.35 and 0.52)., Conclusions: STA®-Staclot®DRVV-Confirm provides a rapid estimation of the intensity of anticoagulation with rivaroxaban or dabigatran without specific calibrators. At Ctrough, thresholds for rivaroxaban and dabigatran can be used to identify supra-therapeutic plasma level. However, this test cannot differentiate the nature of the NOACs. The development of a point-of-care device optimising this method would be of particular interest in emergency situations., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The perioperative management of dabigatran is challenging, and recommendations based on activated partial thromboplastin time (aPTT) and thrombin time (TT) are unsatisfactory. Dedicated coagulation tests have limitations at plasma concentrations < 50 ng/ml. Therefore, a more sensitive test, which is available 24/7, is required. It was the aim of this study to investigate the performance of the Hemoclot Thrombin Inhibitors® LOW (HTI LOW) kit, a diluted thrombin time, and the STA® - ECA II(ECA-II) kit, a chromogenic variant of the ecarin clotting time, that were developed to measure low dabigatran concentrations, compared to reference dabigatran analysis by liquid chromatography tandem mass-spectrometry (LC-MS/MS). This study included 33 plasma samples from patients treated with dabigatran etexilate who had plasma concentrations < 200 ng/ml. HTI LOW and ECA-II were performed along with HTI, aPTT (STA®-C. K.Prest® and SynthasIL®) and TT (STA® - Thrombin). All procedures were performed according to recommendations by the manufacturers. Linear (or curvilinear) correlations and Bland-Altman analyses were calculated. For free dabigatran concentrations < 50 ng/ml, the R² of linear correlations were 0.69, 0.84 and 0.61, with HTI, HTI LOW and ECA-II, respectively. The R² for TT, STA®-C. K.Prest® and SynthasIL® were 0.67, 0.42 and 0.15. For HTI, HTI LOW and ECA-II, Bland-Altman analyses revealed mean differences of -6 ng/ml (95 %CI: -25-14 ng/ml), 1 ng/ml (95 %CI: -18-19 ng/ml) and -1 ng/ml (95 %CI: -25-23 ng/ml), demonstrating that tests dedicated to measuring low concentrations are more accurate than HTI. In conclusion, the use of HTI LOW or ECA-II to assess low plasma dabigatran concentrations is supported by our findings.

Objective: After failure of pharmacological treatment, sinus surgery is the recommended alternative treatment for chronic sinusitis with or without nasal polyps. During post-operative healing, adequate local neutrophil activation plays an important role in the repair process. This pilot study aimed to systematically explore the participation of circulating neutrophils in early-phase wound repair of the nasal and paranasal mucosa after sinus surgery, with a special focus on neutrophil recruitment and activation patterns., Methodology: We conducted a single-center outcome study of patients undergoing sinus surgery. Whole blood samples were collected from eleven patients before surgery and at post-surgical time points of 1 hour and 1, 7, 14, and 30 days. Hematological analysis was conducted to count circulating neutrophils and evaluate their overall activation status. Using flow cytometry, neutrophil expression of membrane CD11b, CD11c, and CD15 was also measured, and oxidative burst analysis was performed., Results: After sinus surgery, neutrophilia increased by 1 hour after surgery, reached a maximum at Day 1, and showed a gradual return toward baseline by Day 30. The oxidative burst initially decreased during the first hours after surgery, increased at Day 14, and returned toward normal by Day 30. Lewis X factor and the expression of CD11b and CD11c exhibited a bimodal change over time, in an inverted phase compared to the oxidative reaction., Conclusions: Circulating neutrophils are involved in the first phase of wound healing after sinus surgery as indicated by increased abundance, early membrane changes, and the modulation of their oxidative capacities.

The Belgian national External Quality Assessment Scheme performed a nationwide survey using lyophilised plasma samples spiked with dabigatran or rivaroxaban to demonstrate to the Belgian clinical laboratories how these drugs affect their routine coagulation assays prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen and antithrombin. Virtually all Belgian laboratories performing routine coagulation testing (189/192) participated in the survey. Both, dabigatran and rivaroxaban significantly prolonged the PT and aPTT in a concentration- and reagent-dependent manner. PT reagents were more influenced by rivaroxaban than by dabigatran and aPTT reagents more influenced by dabigatran than by rivaroxaban. Among PT reagents, Neoplastin R® was the most sensitive to rivaroxaban and Innovin® and Thromborel S® the least sensitive. Converting PT results to INR only increased the variability between reagents. Among aPTT reagents, Actin FSL® was the least sensitive to dabigatran while the other aPTT reagents showed slightly higher sensitivities. The presence of dabigatran led to falsely reduced fibrinogen concentrations when measured with a low thrombin concentration reagent. The presence of dabigatran caused an overestimation of the antithrombin level when measured with a thrombin-based activity assay and the presence of rivaroxaban an overestimation of the antithrombin level when measured with a FXa-based assay. Instrument-related differences were found for all tested parameters. In conclusion, this paper provides detailed information on the effect of dabigatran and rivaroxaban on routine coagulation assays as performed with a large number of reagent/instrument combinations.

Non-VKA oral anticoagulants (NOACs) have now widely reached the lucrative market of anticoagulation. While the marketing authorization holders claimed that no routine monitoring is required and that these compounds can be given at fixed doses, several evidences arisen from the literature tend to demonstrate the opposite. New data suggests that an assessment of the response at the individual level could improve the benefit-risk ratio of at least dabigatran. Information regarding the association of rivaroxaban and apixaban exposure and the bleeding risk is available in the drug approval package on the FDA website. These reviews suggest that accumulation of these compounds increases the risk of experiencing a bleeding complication. Therefore, in certain patient populations such as patients with acute or chronic renal impairment or with multiple drug interactions, measurement of drug exposure may be useful to ensure an optimal treatment response. More specific circumstances such as patients experiencing a haemorrhagic or thromboembolic event during the treatment duration, patients who require urgent surgery or an invasive procedure, or patient with a suspected overdose could benefit from such a measurement. This paper aims at providing guidance on how to best estimate the intensity of anticoagulation using laboratory assays in daily practice.