Loss of sialic acid from the carbohydrate side chains of platelet glycoproteins can affect platelet clearance, a proposed mechanism involved in the etiopathogenesis of immune thrombocytopaenia (ITP). We aimed to assess whether changes in platelet glycosylation in patients with ITP affected platelet counts, function, and apoptosis. This observational, prospective, and transversal study included 82 patients with chronic primary ITP and 115 healthy controls. We measured platelet activation markers and assayed platelet glycosylation and caspase activity, analysing samples using flow cytometry. Platelets from patients with ITP with a platelet count <30 × 10³/µL presented less sialic acid. Levels of α1,6-fucose (a glycan residue that can directly regulate antibody-dependent cellular cytotoxicity) and α-mannose (which can be recognised by mannose-binding-lectin and activate the complement pathway) were increased in the platelets from these patients. Platelet surface exposure of other glycoside residues due to sialic acid loss inversely correlated with platelet count and the ability to be activated. Moreover, loss of sialic acid induced the ingestion of platelets by human hepatome HepG2 cells. Changes in glycoside composition of glycoproteins on the platelets’ surface impaired their functional capacity and increased their apoptosis. These changes in platelet glycoside residues appeared to be related to ITP severity.

Acquired haemophilia A (AHA) is a rare severe bleeding disorder resulting from the production of autoantibodies directed against coagulation factor VIII. At presentation, bleeding events can be severe, and an early diagnosis and treatment are of major importance. The current study aims to analyse the treated patients who have been diagnosed with AHA for a better understanding of our population and treatment outcome. We conducted a retrospective study with 26 patients who had been diagnosed with AHA and who were treated in our hospital between January 2006 and January 2021. The patients ranged in age from 30 to 85 years old: 46.10% were men, 46.10% had no known underlying condition, 27% had an underlying malignancy, 7.60% presented with other diseases: psoriatic arthritis and Paget’s disease, and 19.30% presented with AHA during puerperium. All of the patients had bleeding events and were treated with bypass agents for this as well as with immunosuppressive therapy to eradicate the inhibitor. A total of 53.80% of the patients had major bleeding. Sixty-nine percent of the patients achieved complete remission, but 26.90% died during the follow-up, although bleeding was not the cause of death in any of these cases. Our observations underline the importance of clinical suspicion and early referral to centres with experience and laboratory facilities for managing AHA.

Background and Objectives: The aim of this study was to determine the impact of the COVID-19 pandemic on the lives of patients with immune thrombocytopaenia (ITP) treated at our hospital. Materials and Methods: The study was conducted in the Community of Madrid, which has the highest number of COVID-19 cases in Spain. We included 143 adult patients with ITP (130 with chronic ITP, 8 with persistent ITP, and 5 with newly diagnosed ITP). We conducted a telephone survey to collect the data and created a registry. Materials and Methods: Overall, 24 patients presented symptoms suggestive of COVID-19, which was confirmed by RT-PCR in 8 cases. The cumulative incidence of confirmed SARS-CoV-2 infection was higher in the patients with ITP than in the Madrid population. There were no differences in the disease incidence or clinical course of infection in the patients treated with immunosuppressants. Almost all of the patients reported adherence to the prescribed treatment, although 49.2% of the hospital visits were either cancelled or postponed, 17.2% because of the patients’ fear of coming to the centre. Nearly half of the cohort was considered vulnerable, and 17% had been granted a dependency or disability benefit. Conclusions: COVID-19 had a major impact on the psychosocial, occupational, and quality of care of patients with ITP.

Background/Objectives: Patients with severe hemophilia A on prophylaxis with emicizumab exhibit a mild/moderate bleeding phenotype that requires the use of either recombinant FVIII (rFVIII) or bypassing agents (BPAs) in patients with inhibitors, in the case of breakthrough bleeding or surgery. Since factor IX (FIX) limits the formation of the FIXa–emicizumab–FX complex, exogenously added FIX might enhance complex formation and thrombin generation. This study aimed to compare the procoagulant effects of various FIX concentrates with recombinant activated FVII (rFVIIa), activated prothrombin complex concentrate (aPCC), and rFVIII in SHA patients with and without inhibitors under emicizumab prophylaxis. Methods: Hemostatic changes were monitored using two optimized global coagulation assays: rotational thromboelastometry and calibrated automated thrombin generation. Tubes containing corn trypsin inhibitor (CTI) were used during blood collection to prevent activation. Low concentrations of tissue factor (TF) were used to trigger coagulation in both assays. Results: Ex vivo addition of recombinant FIX concentrates significantly increased the procoagulant activity of emicizumab, achieving levels comparable to therapeutic doses of rFVIIa or rFVIII, and the proportion of active FIXa within the concentrates is a major contributor to their procoagulant function. We assessed the influence of FVIII inhibitors on the hemostatic efficacy of rFIX concentrates and BPAs, finding that rFIX-induced thrombin generation increased in the presence of inhibitors, and no significant differences were observed with BPAs. Conclusions: These findings suggest that FIX concentrates could be an effective alternative to BPAs for emicizumab-treated patients, particularly those with inhibitors. Further studies are needed to confirm their in vivo efficacy and to evaluate thrombotic risk.

Introduction and Importance: Acquired von Willebrand disease (AvWD) is a rare underdiagnosed bleeding disorder caused by alterations in the levels of the major blood clotting protein von Willebrand factor (vWF). The clinical and laboratory parameters of AvWD are similar to congenital vWD, but it is found in individuals with no positive family history with no underlying genetic basis. The disease remains multifactorial and incompletely understood. Proposed mechanisms include the development of autoantibodies to vWF, absorption of high molecular weight vWF multimers that impair normal function, shear stress induced vWF cleavage and increased proteolysis. The etiology of the disease is variable, the most common being hematoproliferation, lymophoproliferation, myeloproliferation and autoimmune and cardiovascular disorders. Consensus and protocols for AvWD patients that require major surgery are currently lacking. Patients with AvWD can experience thrombotic events during surgery as a result of therapeutic interactions with pro-thrombotic risk factors. Case Presentation: Here, we report a patient with AvWD requiring a knee prosthesis implantation due to chronic pain, limited range of motion and functional impairment. The patient had a high risk of bleeding during surgery and was at risk of thrombosis due to age and obesity. Clinical Discussion: Perioperative care required a collaborative approach and the management of bleeding. The patient was administered vWF concentrate Willfact^® lacking Factor VIII to prevent haemorrhage and to minimize the risk of thrombosis. Conclusion: The treatment was effective and well-tolerated. We use this information to provide recommendations for AvWD patients for whom major surgery is indicated.