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An in vitro study simulating prophylactic anticoagulation in haemophilia A and B

2026-11-05T08:34:00Z

Title: An in vitro study simulating prophylactic anticoagulation in haemophilia A and B Authors: Riva, Nicoletta; Vella, Kevin; Hickey, Kieron; Debattista, Nigel; Grima, Carmel; Borg-Aquilina, Denise; Camilleri, Liberato; Guo, Jiong Jiong; Gatt, Alexander Abstract: Introduction: Patients with haemophilia A (HA) and haemophilia B (HB) are at increased bleeding risk. A recent guidance document suggests considering pharmacological thromboprophylaxis on a case-by-case basis in these patients undergoing surgery at high-risk of venous thromboembolism. This study aimed to assess the effect of prophylactic doses of three anticoagulants (enoxaparin, rivaroxaban and unfractionated heparin [UFH]) on in vitro models of HA and HB. Methods: FVIII- and FIX-deficient plasma were spiked with FVIII and FIX concentrates to mimic severe, moderate and mild HA (FVIII concentrations < 1%, 1.2% and 17.0%, respectively) and HB (FIX concentrations < 1%, 3.9% and 22.9%, respectively). Each pool was spiked with enoxaparin (concentration range 0.3–0.4 IU/mL), rivaroxaban (50–100 ng/mL) and UFH (0.2–0.3 IU/mL). The following assays were performed: prothrombin time (PT), activated partial thromboplastin time (APTT) and thrombin generation (using the semi-automated fluorogenic calibrated automated thrombin generation assay [CAT]). Results: The PT was not significantly affected by the anticoagulants. A significant prolongation of the APTT was observed; UFH showed the greatest increase, followed by rivaroxaban and enoxaparin. All anticoagulants impacted on the CAT curves. UFH showed the greatest reduction of the endogenous thrombin potential; rivaroxaban showed the greatest increase of lag time and time to peak. Peak thrombin and velocity index were similarly reduced by rivaroxaban and UFH, whereas enoxaparin was associated with smaller changes in all parameters. Conclusion: A significant effect of three prophylactic anticoagulants was observed in factor-deficient plasmas. This study provides further insight into this topic and supports the concept of an individualised approach to haemophilia patients.

Haemostasis in kidney failure

2026-10-28T13:17:45Z

Title: Haemostasis in kidney failure Authors: Caruana, Jessica; Riva, Nicoletta; Gatt, Alexander Abstract: Introduction to the pathophysiology of haemostasis in kidney failure The haemostatic system is a finely balanced biological mechanism that maintains an equilibrium between the procoagulant and anticoagulant pathways. This complex system is dynamic, whereby the procoagulant pathway is set in motion in cases of vascular injury to ensure haemostasis, while the anticoagulant pathway prevents excessive blood clotting (thrombosis). Kidney failure (KF), that is the final and permanent stage of chronic kidney disease (CKD), knocks this delicate balance out of kilter, making KF patients susceptible to both thrombotic and bleeding episodes. The pathophysiology of this paradox is intricate and multifactorial. Increased thrombotic risks are attributed to chronic inflammation and endothelial cell damage, whereas bleeding tendencies are associated with primary haemostatic interferences and anaemia of chronic disease3. Risks of thromboembolic complications tend to be exacerbated in KF due to accompanying comorbidities such as cardiovascular disease (CVD) and diabetes mellitus (DM). CKD is a persistent and progressive condition affecting more than 850 million individuals worldwide4. Kidney Disease Improving Global Outcomes (KDIGO) guidelines define KF as aglomerularfiltration rate (GFR)that is less than 15 ml/min/1.73 m2. At this stage patients are typically required to undergo long-term dialysis treatment or kidney transplantation.

Management diagnostico-terapeutico delle trombosi venose in siti inusuali

2026-10-28T10:28:59Z

Title: Management diagnostico-terapeutico delle trombosi venose in siti inusuali Authors: Caiano, Lucia; Riva, Nicoletta; Ageno, Walter Abstract: Le trombosi venose cerebrali possono interessare una o piu vene del distretto cerebrale (comprendente sia le vene corticali sia le vene cerebrali profonde), oppure i seni venosi della dura madre (seno sagittale superiore, seni laterali o trasversi, seno retto, seno sigmoideo, seno cavernoso). A seconda della sede interessata e dell'estensione della trombosi, le manifestazioni cliniche saranno differenti. Le sedi piu spesso coinvolte sono il seno sagittale superiore (fino al 62% dei casi), i seni trasversi (40-45%), il seno retto (18%) e le vene corricali (17%). In circa due terzi dei pazienti puo essere coinvolto piu di un seno venoso. La diagnosi puo essere difficoltosa e tardiva perche i segni e i sintomi possono mimare le manifestazioni di altre patologie cerebrali. La prognosi puo essere severa, mentre complessivamente le recidive non sono frequenti.

“The ISTH SSC subcommittee on hemostatic management of patients with liver disease : goals, ambitions, and call for collaboration” : reply

2026-10-27T14:16:06Z

Title: “The ISTH SSC subcommittee on hemostatic management of patients with liver disease : goals, ambitions, and call for collaboration” : reply Authors: Lisman, Ton; Carlin, Stephanie; Gatt, Alexander; Hernandez-Gea, Virginia; Luyendyk, James P.; Roberts, Lara N.; Stanworth, Simon J. Abstract: We thank Tripodi and Mannucci for their interest in our recent editorial, in which we introduce the International Society on Thrombosis and Haemostasis Scientific and Standardization Committee (SSC) on Hemostatic Management of Patients with Liver Disease. We share their enthusiasm regarding the support of ISTH for this topic and agree that the thrombosis and hemostasis community recognized the relevance of this topic somewhat later than other communities. Indeed, international societies on hepatology, anesthesia, and surgery have had this topic on their agendas for a number of years. We are very glad to bring the expertise of the thrombosis and hemostasis community to the forefront of this effort through the newly established SSC subcommittee.