Publications by authors named "Alain Stépanian"

44 Publications

[Acquired hemophilia A: clinical and biological characteristics and therapeutic management of a series of eight patients hospitalized in Lariboisière and Saint-Louis hospitals].

Ann Biol Clin (Paris) 2021 Feb;79(1):75-82

Service d'hématologie biologique, CRMR des MAT-laboratoire ADAMTS13, CRMR de la Maladie de Willebrand, DMU BioGEM, Hôpital Lariboisière, AP-HP Nord, Université de Paris, Paris, France, EA-3518 Recherche clinique en hématologie, immunologie et transplantation, Groupe MicroAngiopathies Thrombotiques, VWF et ADAMTS13, Institut de recherche Saint-Louis, Université de Paris, Paris, France.

Acquired hemophilia A is a rare autoimmune disease, linked to the appearance of autoantibodies directed against circulating factor VIII, and characterized by a major hemorrhagic syndrome. Acquired hemophilia A is a life-threatening diagnostic and therapeutic medical emergency. We describe here the cohort of patients with acquired hemophilia A treated between 2015 and 2020 at Lariboisière and Saint-Louis University Hospitals (Paris, France). We remind you here of the measures to be taken without delay in the face of any clinical and/or biological suspicion. Management is based on three main areas published in multicentre cohort studies, essentially observational: symptomatic treatment to control the hemorrhagic syndrome, immunosuppressive treatment to eradicate autoantibodies and manage their possible complications, and etiological treatment of the underlying pathology for secondary forms.
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http://dx.doi.org/10.1684/abc.2021.1625DOI Listing
February 2021

ADAMTS13 and von Willebrand factor assessment in steady state and acute vaso-occlusive crisis of sickle cell disease.

Res Pract Thromb Haemost 2021 Jan 18;5(1):197-203. Epub 2020 Dec 18.

Service d'Hématologie Biologique Hôpital Lariboisière AP-HP.Nord Université de Paris Paris France.

Background: Sickle cell disease (SCD) is characterized by vaso-occlusive crisis (VOC), acute chest syndrome (ACS) and multiorgan failure (MOF) complicated by thrombosis. Von Willebrand factor (VWF) is a strong marker of SCD-related endothelial injury.

Objectives: To decipher the role of VWF and its specific-cleaving metalloprotease, ADAMTS13, in the vaso-occlusive and thrombotic process of SCD.

Patients/methods: We investigated the VWF antigen (Ag), ADAMTS13 activity, ADAMTS13 Ag and ADAMTS13 IgGs in a cohort of 65 patients with SCD prospectively enrolled in a 20-month period from three centers. Patients were divided into two groups: an asymptomatic group (n = 30) with treated or untreated SCD at steady state, and a VOC/ACS group (n = 35) with SCD with VOC/ACS requiring either medical management or intensive care management for MOF.

Results And Conclusions: VWF:Ag levels were increased (median, 167 IU/dL; interquartile range [IQR], 124 - 279), especially in patients with VOC SCD (227 IU/dL; IQR, 134-305;  = .04), and positively correlated with inflammatory markers ( < .02). Median ADAMTS13 activity was normal (70 IU/dL; IQR, 60-80), but 7 patients exhibited a partial deficiency between 25 and 45 IU/dL. ADAMTS13 activity/VWF:Ag ratio, however, did not change during VOC. Median ADAMTS13:Ag was slightly decreased (611 ng/mL; IQR, 504-703) with no significant difference between groups. Surprisingly, ADAMTS13 IgGs were detected in 33 (51%) of our patients. We conclude that, in SCD, VWF:Ag and nonrelevant ADAMTS13 IgGs may reflect the severity of the inflammatory vasculopathy enhancing vaso-occlusive and thrombotic complications.
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http://dx.doi.org/10.1002/rth2.12460DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7845082PMC
January 2021

Diagnosis and follow-up of thrombotic thrombocytopenic purpura with an automated chemiluminescent ADAMTS13 activity immunoassay.

Res Pract Thromb Haemost 2021 Jan 15;5(1):81-93. Epub 2020 Dec 15.

Service d'hématologie Biologique Hôpital Lariboisière, AP-HP.Nord and EA3518 Institut de Recherche Saint-Louis Université de Paris Paris France.

Background: Thrombotic thrombocytopenic purpura (TTP) is a life-threatening thrombotic microangiopathy (TMA) caused by a severe functional deficiency in ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type I repeats-13), the specific von Willebrand factor (VWF) cleaving protease. ADAMTS13 activity is essential to diagnose TTP but remains challenging to assess, as reference ADAMTS13 activity assays are manual and time consuming. Current techniques also lack robustness in low detectable ADAMTS13 activity range, which could prove problematic for therapy-driven monitoring.

Objectives: The HemosIL AcuStar ADAMTS13 activity assay is a fast, automated chemiluminescent assay, the performance of which remains to be evaluated prospectively on very large cohorts of patients with TMA and in real-life conditions.

Patients And Methods: Our study was conducted over two successive sequences: a retrospective evaluation followed by a "real-life" prospective evaluation. Overall, we evaluated the HemosIL AcuStar ADAMTS13 activity assay on 539 citrated plasma samples. We extensively studied linearity, limit of detection, contamination, intra-assay and interassay precisions with a specific focus on levels < 25 IU/dL. Diagnostic performances for the detection of < 10 IU/dL ADAMTS13 activity and overall method comparison were conducted with the fluorescence resonance energy transfer (FRETS)-VWF73 assay as the reference method.

Results: Technical performance proved excellent. Robustness in low detectable ADAMTS13 activity range was good, potentially qualifying this assay for therapy-driven monitoring. Comparison with the FRETS-VWF73 assay was satisfactory ( = .83,  < .0001) as were the diagnostic performances for acute-phase TTP (specificity, 99.7%; positive predictive value, 99.2%).

Conclusion: The HemosIL AcuStar ADAMTS13 activity assay is a fast, reliable, automated technique well adapted as a first-line ADAMTS13 activity assay for TTP diagnosis and follow-up.
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http://dx.doi.org/10.1002/rth2.12461DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7845081PMC
January 2021

Performance of Diagnostic Scores in Thrombotic Microangiopathy Patients in the Intensive Care Unit: A Monocentric Study.

Thromb Haemost 2021 Jan 29. Epub 2021 Jan 29.

Service de Médecine Intensive-Réanimation, Hôpital Saint-Louis, APHP, Paris, France.

Early thrombotic thrombocytopenic purpura (TTP) recognition is critical as this disease is almost always lethal if not treated promptly with therapeutic plasma exchanges. Currently, as ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) activity is not widely available in emergency, scores have been developed to help differentiating TTP from other thrombotic microangiopathies (TMAs). The aim of this work was to study the accuracy of these diagnostic scores in the intensive care unit (ICU) setting. Performance of both Coppo and PLASMIC scores was studied in a cohort of adult TMA patients requiring admission to one university hospital ICU from 2006 to 2017. Receiver operating characteristic (ROC) curves were established, and confidence intervals of the area under the curve (AUC) were determined. Multivariate logistic regression analysis was performed to identify parameters specifically associated with TTP, to compare diagnostic scores and to elaborate more accurate diagnostic models. During the study period, 154 TMA patients required ICU admission, including 99 (64.2%) TTP and 55 (35.7%) non-TTP patients. AUC under the ROC curve in predicting TTP was 0.86 (95% confidence interval [CI]: 0.81-0.92) for the Coppo score, 0.67 (95% CI: 0.58-0.76) for the PLASMIC score, and 0.86 (95% CI: 0.81-0.92) for platelet count alone. Platelet count ≤20 G/L, determined as the best cut-off rate for thrombocytopenia, performed similarly to the Coppo score and better than the PLASMIC score to differentiate TTP from non-TTP patients, both using AUC ROC curve and logistic regression. In a monocentric cohort of TMA patients requiring ICU admission, the PLASMIC score had limited performance for the diagnosis of TTP. The performance of the Coppo score was good but similar to a single highly discriminant item: platelet count ≤20 G/L at admission.
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http://dx.doi.org/10.1055/a-1378-3804DOI Listing
January 2021

Pathophysiological Processes Underlying the High Prevalence of Deep Vein Thrombosis in Critically Ill COVID-19 Patients.

Front Physiol 2020 8;11:608788. Epub 2021 Jan 8.

Department of Clinical Physiology, Hôpital Lariboisière, APHP, Faculté de Santé, Université de Paris, Paris, France.

Coronavirus disease 2019 (COVID-19) predisposes to deep vein thrombosis (DVT) and pulmonary embolism (PE) particularly in mechanically ventilated adults with severe pneumonia. The extremely high prevalence of DVT in the COVID-19 patients hospitalized in the intensive care unit (ICU) has been established between 25 and 84% based on studies including systematic duplex ultrasound of the lower limbs when prophylactic anticoagulation was systematically administrated. DVT prevalence has been shown to be markedly higher than in mechanically ventilated influenza patients (6-8%). Unusually high inflammatory and prothrombotic phenotype represents a striking feature of COVID-19 patients, as reflected by markedly elevated reactive protein C, fibrinogen, interleukin 6, von Willebrand factor, and factor VIII. Moreover, in critically ill patients, venous stasis has been associated with the prothrombotic phenotype attributed to COVID-19, which increases the risk of thrombosis. Venous stasis results among others from immobilization under muscular paralysis, mechanical ventilation with high positive end-expiratory pressure, and pulmonary microvascular network injuries or occlusions. Venous return to the heart is subsequently decreased with increase in central and peripheral venous pressures, marked proximal and distal veins dilation, and drops in venous blood flow velocities, leading to a spontaneous contrast "sludge pattern" in veins considered as prothrombotic. Together with endothelial lesions and hypercoagulability status, venous stasis completes the Virchow triad and considerably increases the prevalence of DVT and PE in critically ill COVID-19 patients, therefore raising questions regarding the optimal doses for thromboprophylaxis during ICU stay.
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http://dx.doi.org/10.3389/fphys.2020.608788DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7820906PMC
January 2021

The clinical picture of thrombotic microangiopathy in patients older than 60 years of age.

Br J Haematol 2021 Jan 20;192(1):e25-e28. Epub 2020 Nov 20.

Medical Intensive Care Unit, Saint-Louis Hospital, APHP, Paris, France.

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http://dx.doi.org/10.1111/bjh.17176DOI Listing
January 2021

Plasma Serotonin is Elevated in Adult Patients with Sudden Sensorineural Hearing Loss.

Thromb Haemost 2020 Sep 27;120(9):1291-1299. Epub 2020 Jul 27.

Université de Paris, Paris, France.

Background:  The roles of thrombophilia and cardiovascular risk factors in sudden sensorineural hearing loss (SSNHL) remain controversial. Cochlear microthrombosis and vasospasm have been hypothesized as possible pathogenic mechanisms of SSNHL. This article investigates the circulating serotonin and homocysteine levels besides thrombophilia screening in patients with idiopathic SSNHL.

Methods:  A total of 133 SSNHL patients and age- and sex-matched controls were investigated (discovery cohort). Measurement included common inherited natural coagulation inhibitors, factor VIII, von Willebrand factor (VWF), antiphospholipid antibodies, homocysteine, and serotonin (whole blood, platelet, and plasma) levels, along with frequent relevant genetic variants. A validation cohort (128 SSNHL patients) was studied for homocysteine and serotonin levels.

Results And Conclusion:  In the discovery cohort, 58.6% of patients exhibited thrombophilia, of which most had a low to moderate titers of antiphospholipid antibodies and high levels of factor VIII/VWF. Twenty-seven patients (20%) had mild-to-moderate hyperhomocysteinemia or were homozygous for the methylenetetrahydrofolate reductase () C677T mutation. Regarding serotonin, SSNHL patients had elevated whole blood levels that remained within the normal range and normal platelet content. However, approximately 90% patients of both cohorts had elevated plasma serotonin. Elevated plasma serotoninemia was accompanied by serotonylation of platelet rhoA protein. This study shows that increased plasma serotonin appears as a biomarker of SSNHL (specificity: ∼96%, sensitivity: ∼90%) and could participate in the pathophysiology of SSNHL.
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http://dx.doi.org/10.1055/s-0040-1713924DOI Listing
September 2020

Are antiphospholipid antibodies associated with thrombotic complications in critically ill COVID-19 patients?

Thromb Res 2020 11 8;195:74-76. Epub 2020 Jul 8.

Department of Medical and Toxicological Critical Care, Lariboisière Hospital, Paris University, Paris, France; INSERM UMRS 1144, Paris University, Paris, France.

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http://dx.doi.org/10.1016/j.thromres.2020.07.016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7342042PMC
November 2020

Placental Overexpression of Soluble CORIN in Preeclampsia.

Am J Pathol 2020 05 19;190(5):970-976. Epub 2020 Feb 19.

Université de Paris, National Institute of Health and Medical Research (INSERM), UMR-S1139, 3PHM, Paris, France; PremUp Foundation, Paris, France; University Hospital Federations (FHU) PREMA, Paris, France; Department of Gynaecology-Obstetrics, Port-Royal Hospital, AP-HP, Paris, France.

Preeclampsia (PE) is a hypertensive disease of pregnancy associated with substantial maternal and fetal morbidity and mortality. CORIN is a transmembrane type II serine protease expressed in cardiomyocytes that converts pro-atrial natriuretic peptide into atrial natriuretic peptide, a cardiac hormone that regulates blood pressure. High levels of soluble CORIN have been reported in PE and are supposed to be cardiac in origin. We hypothesized that during pregnancy soluble CORIN is released by the syncytiotrophoblast and that increased levels of soluble CORIN in preeclampsia originate from placenta. A total of 375 patients (181 PE patients and 194 controls) were analyzed. High levels of soluble CORIN were confirmed in maternal blood from preeclamptic pregnancies compared with controls. Differentiated primary villous cytotrophoblasts showed that CORIN was expressed (mRNA and protein levels) and secreted by trophoblastic cells, mostly by the syncytiotrophoblast. Finally, placental explants showed a significant increase in CORIN production and secretion in PE cases compared with controls. This study showed that CORIN is secreted by trophoblastic cells and that high levels of soluble CORIN in preeclampsia have a placental origin.
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http://dx.doi.org/10.1016/j.ajpath.2019.12.012DOI Listing
May 2020

Potential usefulness of activated charcoal (DOAC remove®) for dRVVT testing in patients receiving Direct Oral AntiCoagulants.

Thromb Res 2019 Dec 5;184:86-91. Epub 2019 Nov 5.

Service d'Hématologie Biologique, CHU Pontchaillou, Rennes, France; University of Rennes 1, CIC-Inserm1414, Rennes, France.

Introduction: Lupus Anticoagulant testing using dilute Russell Viper Venom Time (dRVVT) is challenging in patients receiving Direct Oral AntiCoagulants (DOAC) due to potential false positive results. In a multicenter study, we evaluated the in vitro removal of DOAC by activated charcoal (DOAC remove®), allowing reliable dRVVT testing.

Materials And Methods: Patient samples were analyzed before and after treatment with DOAC remove®: 49 apixaban, 48 rivaroxaban, 24 dabigatran and 30 none. DOAC plasma concentrations were measured using anti-Xa or diluted thrombin time assays. In a subset of 28 samples, DOAC concentrations were also measured using HPLC-MS/MS following treatment with DOAC remove®. DRVVT was performed using STA-Staclot dRVVT Screen®/Confirm® (Stago) or LAC-Screening®/Confirmation® (Siemens).

Results: Baseline median [min-max] concentrations were 94 [<20-479] for apixaban, 107 [<20-501] for rivaroxaban and 135 ng/mL [<20-792] for dabigatran; dRVVT screen ratio/confirm ratio was positive in 47, 90 and 42% of apixaban, rivaroxaban and dabigatran samples. Treatment with DOAC remove® did not affect dRVVT results in non-DOAC patients while it resulted in DOAC concentrations <20 ng/mL in 82, 98 and 100% of samples, respectively. Concentrations were <5 ng/mL with HPLC-MS/MS in 5 out of 10, 8 out of 10 and 7 out of 8 samples, respectively. DOAC remove® corrected DOAC interference with dRVVT assays in 76, 85 and 95% of the patients, respectively.

Conclusion: For dRVVT testing in DOAC patients, we suggest the use of DOAC remove® for every rivaroxaban sample, whereas it might only be used in positive apixaban and dabigatran samples. A residual DOAC interference cannot be ruled out in case of persisting dRVVT positive results after treatment with DOAC remove®.
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http://dx.doi.org/10.1016/j.thromres.2019.11.001DOI Listing
December 2019

Loss of von Willebrand factor high-molecular-weight multimers at acute phase is associated with detectable anti-ADAMTS13 IgG and neurological symptoms in acquired thrombotic thrombocytopenic purpura.

Thromb Res 2019 Sep 16;181:29-35. Epub 2019 Jul 16.

Service d'Hématologie Biologique, Hôpital Lariboisière, Assistance Publique-Hôpitaux de Paris, Paris, France; EA3518, Institut Universitaire d'Hématologie Saint Louis, Université Paris Diderot, Paris, France. Electronic address:

Introduction: Thrombotic thrombocytopenic purpura (TTP) is a rare life threatening thrombotic microangiopathy caused by a severe functional deficiency of ADAMTS13, most frequently due to autoantibodies to ADAMTS13, thus termed acquired autoimmune TTP. ADAMTS13 specifically regulates the adhesive activity of von Willebrand factor (VWF) by cleaving its high-molecular-weight multimers (HMWM). We investigated whether VWF-HMWM level at acute phase of TTP could be a predictive factor for morbidity.

Material And Methods: We gathered clinical and biological data from a cohort of 114 patients with acquired TTP at acute phase. VWF-HMWM were assessed by electrophoretic analysis and by an ELISA measuring the capacity of VWF to bind to collagen (VWF:CB), and linear correlation between these two methods was carried out. We cross-referenced clinical and biological data with VWF-HMWM levels.

Results: VWF-HMWM levels were heterogeneous, but half of our patients were below normal range (50% if assessed by electrophoresis; 47.4% if assessed by ELISA). The correlation study between electrophoresis and ELISA reached statistical significance (r = 0.5979; p < 0.0001). Statistical analysis showed that loss of VWF-HMWM as assessed by VWF:CB < 70 IU/dL is associated with detectable anti-ADAMTS13 antibodies, severe neurological symptoms and thrombocytopenia (p < 0.05).

Conclusion: Our results confirm that VWF-HMWM can be satisfactorily assessed by VWF:CB, much easier to perform than electrophoresis. The association highlighted between loss of VWF-HMWM, detectable anti-ADAMTS13 IgG and neurological symptoms may offer new insights to understanding the pathophysiology of acquired auto-immune TTP.
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http://dx.doi.org/10.1016/j.thromres.2019.07.012DOI Listing
September 2019

Multifactorial hypercoagulable state associated with a thrombotic phenotype in phosphomannomutase-2 congenital disorder of glycosylation (PMM2-CDG): Case report and brief review of the literature.

Thromb Res 2019 Jun 9;178:75-78. Epub 2019 Apr 9.

Service d'hématologie biologique, Hôpital Lariboisière, AP-HP, Paris, France; INSERM UMR_S1140, Université Paris Descartes, Paris, France. Electronic address:

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http://dx.doi.org/10.1016/j.thromres.2019.04.010DOI Listing
June 2019

[Von Willebrand disease in the elderly].

Rev Prat 2018 Dec;68(10):1125-1131

Service d'hématologie biologique, site constitutif du centre de référence maladie rare de la maladie de Willebrand, hôpital Lariboisière, AP-HP, Paris, France.

Von Willebrand disease in the elderly. Von Willebrand disease (VWD) is a rare inherited haemorrhagic disorder, the prevalence of symptomatic individuals is around 1/10 000. Von Willebrand factor level increases with advanced age, explaining a lower frequency and a lower severity of cutaneous haemorrhagic symptoms with aging. The management of comorbidities in VWD patients is multidisciplinary, on a case by case basis, taking into account scientific society guidelines and haemostasis expert recommendations. The haemorrhagic risk should be systematically evaluated before an invasive procedure or the start of treatment with anticoagulant or antiplatelet drugs, or before the use of some cancer chemotherapy.
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December 2018

Platelet Functions are Decreased in Obesity and Restored after Weight Loss: Evidence for a Role of the SERCA3-Dependent ADP Secretion Pathway.

Thromb Haemost 2019 Mar 16;119(3):384-396. Epub 2019 Jan 16.

Université Paris Diderot, Sorbonne Paris Cité, Paris, France.

In obesity, platelets are described as hyperactive, mainly based on increased platelet size and presence of pro-thrombotic plasmatic molecules. We explored platelet functions, including calcium signalling in obesity, and the effect of weight loss. We included 40 obese patients (women with body mass index [BMI] of ≥ 35 kg/m) who were to undergo gastric bypass surgery and 40 healthy lean subjects (women with BMI of < 25 kg/m) as a control group. Approximately 1 year after surgery, the obese patients lost weight (75% had a BMI < 35 kg/m). They were explored a second time with the same healthy control for the same platelet experiments. Compared with controls, obese patients' platelets displayed reduced sensitivity to thrombin (aggregation EC increased by 1.9 ± 0.3-fold,  = 0.005) and a lower Ca response (70 ± 7% decrease, < 10). In 17 pairs of patients, we performed additional experiments: in obese patients' platelets, thrombin-induced αIIbβ3 activation was significantly lower ( = 0.003) and sarco-endoplasmic reticulum CaATPase (SERCA3) expression was decreased (48 ± 6% decrease, < 10). These differences were abolished after weight loss. Interestingly, pharmacological inhibition of SERCA3 activity in control group's platelets mimicked similar alterations than in obese patients' platelets and was associated with defective adenosine diphosphate (ADP) secretion. Addition of ADP to agonist restored platelet functions in obese patients and in SERCA3-inhibited control platelets (five experiments) confirming the direct involvement of the SERCA3-dependent ADP secretion pathway. This is the first study demonstrating that platelets from obese patients are hypo-reactive, due to a deficiency of SERCA3-dependent ADP secretion. Weight loss restores SERCA3 activity and subsequent calcium signalling, αIIbβ3 activation, platelet aggregation and ADP secretion.
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http://dx.doi.org/10.1055/s-0038-1677033DOI Listing
March 2019

ADAMTS13 Gene Mutations Influence ADAMTS13 Conformation and Disease Age-Onset in the French Cohort of Upshaw-Schulman Syndrome.

Thromb Haemost 2018 Nov 12;118(11):1902-1917. Epub 2018 Oct 12.

Institut Universitaire d'Hématologie, Université Paris Diderot, Hôpital Saint-Louis, Assistance Publique-Hôpitaux de Paris, Paris, France.

Background:  Congenital thrombotic thrombocytopaenic purpura (TTP) or Upshaw-Schulman syndrome (USS) is a rare, life-threatening, inherited thrombotic microangiopathy (TMA). USS is mostly due to bi-allelic recessive sequence variations of the () gene inducing a severe ADAMTS13 deficiency (activity < 10 IU/dL). In healthy individuals, ADAMTS13 circulates in a folded conformation where CUB domains interact with the spacer domain. The spacer-CUB interaction is abrogated when ADAMTS13 is conformationally activated.

Objective:  This article evaluates the influence of sequence variations on both clinical/biological phenotype and ADAMTS13 conformation in USS.

Patients And Methods:  All USS patients from the French registry for TMAs (1 January 2000 to 1 June 2017) were investigated for ADAMTS13 genotype, phenotype (activity, antigen and autoantibodies) and conformation. Clinical records were analysed (inaugural acute TTP and follow-up). Child-onset USS was compared with adult-onset USS.

Results:  Fifty-six USS patients from 51 families (34 child-onset and 22 adult-onset cases) were enrolled. Child-onset USS was characterized by a large panel of sequence variations ( = 43), spread all over gene and not correlated with either clinical features or plasmatic ADAMTS13 parameters. In contrast, adult-onset USS, consisting exclusively in pregnancy-induced TTP, included a smaller and distinct panel of sequence variations ( = 20) because of one mutation (p.Arg1060Trp) present in 82% of patients. ADAMTS13 conformation was studied in 16 USS patients (5 child-onset and 11 adult-onset USS, encompassing 16 distinct sequence variations) whose ADAMTS13 antigen levels were detectable: 14 of 16 patients (87.5%) exhibited abnormalities of ADAMTS13 conformation.

Conclusion:  In USS, age-onset defines two entities and sequence variations modify ADAMTS13 conformation.
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http://dx.doi.org/10.1055/s-0038-1673686DOI Listing
November 2018

Modified ROTEM for the detection of rivaroxaban and apixaban anticoagulant activity in whole blood: A diagnostic test study.

Eur J Anaesthesiol 2019 06;36(6):449-456

From the INSERM UMR_S1140, Faculté de Pharmacie (CP, GJ, VS, IG, SG, PG, BL, CMS), Université Paris Descartes (CP, GJ, VS, IG, SG, EC, PG, BL, CMS), Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpital Cochin (CP, GJ, CMS), AP-HP, Hôpital Lariboisière, Paris (VS, AS), CHU Pontchaillou, Rennes (IG), AP-HP, Hôpital Européen Georges Pompidou (SG, PG), EA3518, Hôpital Saint Louis (AS), INSERM UMR_S1144, Faculté de Pharmacie (EC), Laboratoire de Biomathématiques, Faculté de Pharmacie, Université Paris Descartes (EC) and Université Pierre et Marie Curie, Paris, France (JG).

Background: Rapid detection of the anticoagulant effect of oral factor Xa (FXa) inhibitors may be essential in several emergency clinical situations. Specific assays quantifying the drugs are performed in plasma and require a turnaround time that is too long to be useful in emergency situations. Rotational thromboelastometry (ROTEM) is a whole blood coagulation assay of blood viscoelasticity and could be of interest for FXa inhibitor detection in emergency. However, conventional ROTEM reagents only detect high amounts of inhibitors.

Objective: The aim of this study was first to assess the effect of whole blood components on the viscoelastic measurement of the effects of FXa inhibitors, and second to evaluate whether a modified ROTEM, triggered with a low amount of tissue factor and a saturating amount of phospholipid vesicles, can reliably detect low levels of FXa inhibitor activity in whole blood.

Design: Diagnostic test study.

Settings: A university research laboratory. From November 2014 to April 2016.

Patients: Sixty-six patients: 30 treated with rivaroxaban, 17 with apixaban and 19 without treatment.

Intervention: ROTEM was triggered with 2.5 pmol l of tissue factor and 10 μmol l of phospholipid vesicles.

Main Outcome Measures: Modified ROTEM parameters were measured in different experimental conditions: platelet-poor plasma (PPP), platelet-rich plasma, PPP supplemented with fibrinogen and reconstituted whole blood with various haematocrit levels adjusted between 30 and 60%. Modified ROTEM was further validated using whole blood from patients who were either treated or not treated with FXa inhibitors.

Results: Modified ROTEM allowed detection of as little as 25 ng ml FXa inhibitors in PPP, with at least a 1.4-fold increase of the clotting time (P ≤ 0.02). Neither changes of fibrinogen concentration nor variations of platelet count or haematocrit precluded FXa inhibitor detection. A lengthened modified ROTEM clotting time of more than 197 s allowed detection of FXa inhibitor concentrations above 30 ng ml in whole blood with 90% sensitivity and 85% specificity.

Conclusion: Modified ROTEM may be applicable in emergency situations for the detection of FXa inhibitors in whole blood.
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http://dx.doi.org/10.1097/EJA.0000000000000903DOI Listing
June 2019

Deep venous thrombosis treated by rivaroxaban in a young patient with type Ia carbohydrate-deficient glycoprotein (CDG) syndrome.

Ann Biol Clin (Paris) 2018 Apr;76(2):217-223

Service d'hématologie biologique, Hôpital Lariboisière, AP-HP, Paris, France.

Congenital disorders of glycosylation (CDG) are rare inborn diseases of glycan component of N-glycosylated proteins. We report here the case of a 28-year-old patient with CDG syndrome type Ia, who presented with a deep venous thrombosis in the left suro-popliteal vein with no known triggers or antecedents. The patient was treated with rivaroxaban for six months. Blood tests performed after discontinuing anticoagulant treatment showed multiple abnormalities affecting the proteins involved in haemostasis (both coagulation factors and inhibitors), i.e. a combined factor XI, antithrombin and protein C deficiency (35%, 41%, and 42% respectively) associated with a moderate increase of FVIII (179%) and VWFAg (163%) without inflammation. Patient results are here discussed with regard to the limited number of articles addressing haemostasis in this rare disease, as the occurrence of deep venous thrombosis remains uncommon in the literature.
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http://dx.doi.org/10.1684/abc.2018.1324DOI Listing
April 2018

Are Screening Tests Reliable to Rule Out Direct Oral Anticoagulant Plasma Levels at Various Thresholds (30, 50, or 100 ng/mL) in Emergency Situations?

Chest 2018 01;153(1):288-290

Service d'Hématologie biologique, Hôpital Lariboisière (Assistance Publique-Hôpitaux de Paris), Paris, France; INSERM UMR-S 1140, Université Paris Descartes, Sorbonne Paris Cité, Paris, France. Electronic address:

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http://dx.doi.org/10.1016/j.chest.2017.09.047DOI Listing
January 2018

Comparison of risk prediction scores for venous thromboembolism in cancer patients: a prospective cohort study.

Haematologica 2017 09 26;102(9):1494-1501. Epub 2017 May 26.

Department of Vascular Medicine, Academic Medical Center, Amsterdam, the Netherlands.

In ambulatory patients with solid cancer, routine thromboprophylaxis to prevent venous thromboembolism is not recommended. Several risk prediction scores to identify cancer patients at high risk of venous thromboembolism have been proposed, but their clinical usefulness remains a matter of debate. We evaluated and directly compared the performance of the Khorana, Vienna, PROTECHT, and CONKO scores in a multinational, prospective cohort study. Patients with advanced cancer were eligible if they were due to undergo chemotherapy or had started chemotherapy in the previous three months. The primary outcome was objectively confirmed symptomatic or incidental deep vein thrombosis or pulmonary embolism during a 6-month follow-up period. A total of 876 patients were enrolled, of whom 260 (30%) had not yet received chemotherapy. Fifty-three patients (6.1%) developed venous thromboembolism. The c-statistics of the scores ranged from 0.50 to 0.57. At the conventional positivity threshold of 3 points, the scores classified 13-34% of patients as high-risk; the 6-month incidence of venous thromboembolism in these patients ranged from 6.5% (95%CI: 2.8-12) for the Khorana score to 9.6% (95%CI: 6.6-13) for the PROTECHT score. High-risk patients had a significantly increased risk of venous thromboembolism when using the Vienna (subhazard ratio 1.7; 95%CI: 1.0-3.1) or PROTECHT (subhazard ratio 2.1; 95%CI: 1.2-3.6) scores. In conclusion, the prediction scores performed poorly in predicting venous thromboembolism in cancer patients. The Vienna CATS and PROTECHT scores appear to discriminate better between low- and high-risk patients, but further improvements are needed before they can be considered for introduction into clinical practice.
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http://dx.doi.org/10.3324/haematol.2017.169060DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5685240PMC
September 2017

Fatal case of chikungunya and concomitant thrombotic thrombocytopenic purpura in French Guiana during air flight medical evacuation.

J Travel Med 2017 Sep;24(5)

Infectious and Tropical Diseases Unit, Centre Hospitalier Andrée Rosemon, Cayenne F-97300, French Guiana, France.

Thrombotic thrombocytopenic purpura (TTP) is a thrombotic microangiopathy associated to severe ADAMTS13 deficiency. It has been linked to various viral infections. Among arboviruses, only Crimean-Congo haemorrhagic fever and dengue fever have been linked to this severe disease. We report the first documented case of TTP concomitant to Chikungunya virus infection.
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http://dx.doi.org/10.1093/jtm/tax028DOI Listing
September 2017

Child-onset and adolescent-onset acquired thrombotic thrombocytopenic purpura with severe ADAMTS13 deficiency: a cohort study of the French national registry for thrombotic microangiopathy.

Lancet Haematol 2016 Nov 3;3(11):e537-e546. Epub 2016 Oct 3.

Service d'Hématologie biologique, Hôpital Lariboisière, Assistance Publique-Hôpitaux de Paris and EA3518, Institut Universitaire d'Hématologie-Hôpital Saint Louis, Université Paris Diderot, Paris, France. Electronic address:

Background: Thrombotic thrombocytopenic purpura is a rare thrombotic microangiopathy, related to a severe ADAMTS13 deficiency (a disintegrin and metalloprotease with thromboSpondin type 1 repeats, member 13; activity <10% of normal). Childhood-onset thrombotic thrombocytopenic purpura is very rare and initially often misdiagnosed, especially when ADAMTS13 deficiency is acquired (ie, not linked to inherited mutations of the ADAMTS13 gene). We aimed to investigate initial presentation, management, and outcome of acquired thrombotic thrombocytopenic purpura in children.

Methods: Between Jan 1, 2000, and Dec 31, 2015, we studied a cohort of patients with child-onset and adolescent-onset acquired thrombotic thrombocytopenic purpura included in the French national registry for thrombotic microangiopathies at presentation and during follow up. The inclusion criteria were: first episode before age 18 years; ADAMTS13 activity less than 10% of normal at presentation; positive anti-ADAMTS13 autoantibodies during an episode, or a recovery of ADAMTS13 activity in remission, or both. ADAMTS13 activity and anti-ADAMTS13 autoantibodies were investigated by a central laboratory, and medical records were extensively reviewed to collect clinical and biological features with a standardised form. This study is registered with ClinicalTrials.gov, number NCT00426686.

Findings: We enrolled 973 patients with childhood-onset thrombotic microangiopathy, of whom 74 had a severe ADAMTS13 deficiency (activity <10%) at presentation. 24 patients had an inherited thrombotic thrombocytopenic purpura also known as Upshaw-Schulman syndrome and five did not have follow-up data available, thus 45 children had acquired thrombotic thrombocytopenic purpura and were included in our database at presentation. 25 (56%) patients had idiopathic disease and 20 (44%) had miscellaneous associated clinical conditions. At diagnosis, median age was 13 years (IQR 7-16, range 4 months-17 years), with a sex ratio of 2·5 girls to 1 boy. Anti-ADAMTS13 autoantibodies were positive in 37 (82%) of 45 patients (24 [96%] of 25 idiopathic cases and 13 [65%] of 20 non-idiopathic cases). 39 (87%) of 45 patients were given plasma therapy and 21 (47%) received additional rituximab. Four (9%) children died after the first thrombotic thrombocytopenic purpura episode. Long-term follow up of the 41 survivors showed that ten (24%) patients relapsed and systemic lupus erythematosus occurred in two (5%) patients. Preemptive rituximab was used in seven (17%) of 41 patients with acquired thrombotic thrombocytopenic purpura.

Interpretation: Our study shows that child-onset and adolescent-onset acquired thrombotic thrombocytopenic purpura have specific clinical, biological and therapeutic features. Long-term follow-up is crucial to prevent relapses of the disease, to identify the occurrence of autoimmune disorders, and to evaluate consequences on social life. Child-onset and adolescent-onset acquired thrombotic thrombocytopenic purpura is a crucial diagnosis in the field of paediatric haematologic cytopenias because it is a life-threatening disease requiring a specific management.

Funding: Assistance Publique-Hôpitaux de Paris, France.
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http://dx.doi.org/10.1016/S2352-3026(16)30125-9DOI Listing
November 2016

Epidemiology and pathophysiology of adulthood-onset thrombotic microangiopathy with severe ADAMTS13 deficiency (thrombotic thrombocytopenic purpura): a cross-sectional analysis of the French national registry for thrombotic microangiopathy.

Lancet Haematol 2016 May 16;3(5):e237-45. Epub 2016 Apr 16.

Service d'Hématologie biologique, Hôpital Lariboisière, Assistance Publique-Hôpitaux de Paris and EA3518, Institut Universitaire d'Hématologie-Hôpital Saint Louis, Université Paris Diderot, Paris, France. Electronic address:

Background: Thrombotic thrombocytopenic purpura is a thrombotic microangiopathy related to a severe deficiency of ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 repeats, member 13; activity <10%). We aimed to investigate the association between mechanisms for ADAMTS13 deficiency and the epidemiology and pathophysiology of thrombotic thrombocytopenic purpura at initial presentation.

Methods: Between Jan 1, 1999, and Dec 31, 2013, we did a cross-sectional analysis of the French national registry for thrombotic microangiopathy to identify all patients with adult-onset thrombotic microangiopathy (first episode after age 18 years) who had severe ADAMTS13 deficiency at presentation. ADAMTS13 activity, anti-ADAMTS13 IgG, and ADAMTS13 gene mutations were investigated by a central laboratory. We collected patients' clinical data for correlation with their ADAMTS13 phenotype and genotype. We used logistic regression analysis to identify variables significantly associated with idiopathic thrombotic thrombocytopenic purpura, as measured by estimated odds ratios (ORs) and 95% CIs. This study is registered with ClinicalTrials.gov, number NCT00426686.

Findings: We enrolled 939 patients with adult-onset thrombotic thrombocytopenic purpura, of whom 772 (82%) patients had available data and samples at presentation and comprised the cohort of interest. The prevalence of thrombotic thrombocytopenic purpura in France was 13 cases per million people. At presentation, 378 (49%) patients had idiopathic thrombotic thrombocytopenic purpura, whereas 394 (51%) patients had disease associated with miscellaneous clinical situations (infections, autoimmunity, pregnancy, cancer, organ transplantation, and drugs). Pathophysiologically, three distinct forms of thrombotic thrombocytopenic purpura were observed: 585 (75%) patients had autoimmune disease with anti-ADAMTS13 IgG, 166 (22%) patients had acquired disease of unknown cause and 21 (3%) patients had inherited disease (Upshaw-Schulman syndrome) with mutations of the ADAMTS13 gene. Idiopathic thrombotic thrombocytopenic purpura were mainly autoimmune (345 [91%] cases), whereas non-idiopathic diseases were heterogeneous, including a high rate of unexplained mechanisms for ADAMTS13 deficiency (133 [34%] cases). Obstetrical thrombotic thrombocytopenic purpura cases (n=62) were specifically remarkable because of the high rate of patients with Upshaw-Schulman syndrome (21 [34%] patients).

Interpretation: Our study shows that thrombotic thrombocytopenic purpura is a heterogeneous syndrome, and that features of the disease at presentation are strongly associated with the mechanisms of ADAMTS13 deficiency. In addition to mechanistic insight, our findings could have implications for the initial therapeutic management of patients with this disorder.

Funding: Assistance Publique-Hôpitaux de Paris.
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http://dx.doi.org/10.1016/S2352-3026(16)30018-7DOI Listing
May 2016

Apelin: an antithrombotic factor that inhibits platelet function.

Blood 2016 Feb 3;127(7):908-20. Epub 2015 Dec 3.

University of Bordeaux, INSERM U1029, Pessac, France;

Apelin peptide and its receptor APJ are directly implicated in various physiological processes ranging from cardiovascular homeostasis to immune signaling. Here, we show that apelin is a key player in hemostasis with an ability to inhibit thrombin- and collagen-mediated platelet activation. Mice lacking apelin displayed a shorter bleeding time and a prothrombotic profile. Their platelets exhibited increased adhesion and a reduced occlusion time in venules, and displayed a higher aggregation rate after their activation by thrombin compared with wild-type platelets. Consequently, human and mouse platelets express apelin and its receptor APJ. Apelin directly interferes with thrombin-mediated signaling pathways and platelet activation, secretion, and aggregation, but not with ADP and thromboxane A2-mediated pathways. IV apelin administration induced excessive bleeding and prevented thrombosis in mice. Taken together, these findings suggest that apelin and/or APJ agonists could potentially be useful adducts in antiplatelet therapies and may provide a promising perspective for patients who continue to display adverse thrombotic events with current antiplatelet therapies.
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http://dx.doi.org/10.1182/blood-2014-05-578781DOI Listing
February 2016

Coagulation Disorders and Bleedings in Critically Ill Patients With Hemophagocytic Lymphohistiocytosis.

Medicine (Baltimore) 2015 Oct;94(40):e1692

From the Medical ICU, Saint Louis Teaching Hospital, Assistance Publique-Hôpitaux de Paris, 1 avenue Claude Vellefaux, Paris, France (SV, EA, LZ, EC, VL, MV, EM); Paris Diderot University, Sorbonne Paris Cité, Paris, France (SV, EA, LG, DB, LZ, AS, EC, VL, MV, AV, EM); Department of Clinical Immunology, Saint-Louis Teaching Hospital, Assistance Publique-Hôpitaux de Paris, 1 avenue Claude Vellefaux, Paris, France (LG, DB); and Hemostasis Laboratory, Lariboisière Teaching Hospital, 2 rue Ambroise Paré, Paris, France (AS, AV).

Reactive hemophagocytic lymphohistiocytosis (HLH) is a life-threatening condition related to a cytokine storm leading to multiorgan dysfunction. A better understanding of coagulation disorders, frequently reported in HLH patients, may improve outcomes. Critically ill HLH patients managed in a multidisciplinary national reference center were retrospectively included. Relationships between coagulation disorders, severe bleedings, and outcomes were assessed. One hundred and seventeen patients fulfilled the HLH 2004 criteria. The most common HLH etiology was hematologic conditions (73%), followed by infectious diseases (20%), systemic rheumatic diseases (5%), and undetermined HLH etiology (3%). All patients exerted thrombocytopenia. Coagulation disorders were diagnosed in 79 (68%) patients (61 had hypofibrinogenemia < 1.5 g/L, 51 had prothrombin time [PT]  <  0%). The worst median value throughout ICU stay was 52% (38-65) for PT with a factor V level of 35% (27-43), 1.59 (1.30-2.09) for the activated partial thromboplastin time (APTT) ratio, and 2.33 g/L (1.13-3.86) for the fibrinogen level. Disseminated intravascular coagulation (DIC) was found in 50% of patients. Coagulation disorders were more frequent in immunocompromised patients, those with histological/cytological feature of hemophagocytosis, those with the highest ferritin concentrations, and in patients with HLH not related to infection. These patients were more prone to receive mechanical ventilation, vasopressors, or renal replacement therapy. Twenty-six (22%) patients presented severe bleeding complications, including 5 patients dying from hemorrhagic shock. Strikingly, the only coagulation parameter significantly associated with severe bleeding was low fibrinogen with a cutoff value of 2 g/L (P = 0.03). Overall, 33 (28%) patients died in the ICU and hospital mortality was 44%. Coagulation disorders were associated with higher mortality, especially fibrinogen < 2 g/L (P = 0.04) and PT value (P = 0.03). The occurrence of bleeding complications was not associated with higher risk of hospital death. Risk factors associated with mortality by multivariate analysis were fibrinogen level < 2 g/L (OR 2.42 [1.08-5.41]), SOFA score > 6 (OR 3.04 [1.32-6.98]), and age > 46 years (OR 2.26 [1.02-5.04]). Up to two-third of critically ill HLH patients present with coagulation disorders. Hypofibrinogenemia or DIC was found in half of the patients and low PT in 40%. These patients require more life support and have a higher mortality rate. Fibrinogen < 2 g/L is associated with the occurrence of severe bleeding and mortality.
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http://dx.doi.org/10.1097/MD.0000000000001692DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4616770PMC
October 2015