Essentials An international collaboration provides a consensus for clinical definitions. This concerns thrombotic microangiopathies and thrombotic thrombocytopenic purpura (TTP). The consensus ...defines diagnosis, disease monitoring and response to treatment. Requirements for ADAMTS-13 are given.
Background Thrombotic thrombocytopenic purpura (TTP) and hemolytic-uremic syndrome (HUS) are two important acute conditions to diagnose. Thrombotic microangiopathy (TMA) is a broad pathophysiologic process that leads to microangiopathic hemolytic anemia and thrombocytopenia, and involves capillary and small-vessel platelet aggregates. The most common cause is disseminated intravascular coagulation, which may be differentiated by abnormal coagulation. Clinically, a number of conditions present with microangiopathic hemolytic anemia and thrombocytopenia, including cancer, infection, transplantation, drug use, autoimmune disease, and pre-eclampsia and hemolysis, elevated liver enzymes and low platelet count syndrome in pregnancy. Despite overlapping clinical presentations, TTP and HUS have distinct pathophysiologies and treatment pathways. Objectives To present a consensus document from an International Working Group on TTP and associated thrombotic microangiopathies (TMAs). Methods The International Working Group has proposed definitions and terminology based on published information and consensus-based recommendations. Conclusion The consensus aims to aid clinical decisions, but also future studies and trials, utilizing standardized definitions. It presents a classification of the causes of TMA, and criteria for clinical response, remission and relapse of congenital and immune-mediated TTP.
Inhibitors to factor VIII (FVIII) or IX (FIX) in patients with haemophilia A or B create a challenging problem for the treatment of these patients. Recombinant FVIIa (rFVIIa; NovoSeven®, Novo Nordisk ...A/S, Bagsvaerd, Denmark) is a realistic treatment option, owing to its specific mode of action and lack of immunogenicity.
This was a multicentre, open‐label, compassionate‐use trial in patients with severe haemophilia A (FVIII:C < 1%) or B (FIX:C < 1%) with inhibitors, acquired antibodies to FVIII or FIX, or FVII deficiency (FVII:C < 5%), for whom alternative therapies had failed or were contraindicated. Patients received rFVIIa treatment for life‐ or limb‐threatening bleeding episodes or for coverage during essential surgery. The mean rFVIIa dose was approximately 90 μg kg−1 for haemophilia A/B and acquired inhibitor patients, and 25 μg kg−1 for FVII‐deficient patients. Efficacy data for 67 treatment episodes (45 bleeding episodes, 22 surgical procedures) are presented; seven patients were treated for a concurrent serious bleeding episode and surgical procedure. At the end of treatment, rFVIIa was effective or partially effective in 85% of serious bleeding episodes. During surgery, bleeding was assessed as none or less than or equivalent to normal in 91% of surgical procedures; postoperatively, 91% of procedures were associated with no or minimal oozing.
During 60 separate treatment episodes, 26 adverse events (22 nonserious, four serious) were reported in 15 patients, during 17 bleeding episodes or surgical procedures. Only 10 were considered as having a possible, probable, or unknown relationship with rFVIIa; of these, fever (n=2) and thrombophlebitis (n=3) were the most common. There was no evidence of disseminated intravascular coagulation. In conclusion, rFVIIa is an effective, well‐tolerated treatment for serious bleeding episodes and bleeding associated with surgical procedures in patients with severe haemophilia A/B with inhibitors, acquired inhibitors, or FVII deficiency.
Abstract The main aim of this study was to investigate the influence of perioperative anticoagulation on the clinical course and outcome of 144 patients who underwent surgery for chronic subdural ...hematoma (CSDH). The outcome was categorized according to the modified Rankin Scale (mRS), Barthel Index and postoperative quality of life (QoL) scale. There was a significant correlation between preoperative aspirin medication and reoperation (Mann–Whitney U -test, p < 0.05). Moreover, dosage and duration of postoperative low-molecular-weight heparin (LMWH) administration were associated with a higher risk of reoperation (Mann–Whitney U -test, p < 0.01) and a worse outcome on the mRS (Mann–Whitney U -test, p < 0.05). Intraoperative treatment with prothrombin complex concentrate led to a poor outcome on the mRS (Craddock-Flood test, p < 0.05). Reoperation is the strongest predictive factor of a poor QoL after surgical treatment of CSDH. Both preoperative and postoperative anticoagulation treatment may affect reoperation rate and, thus, postoperative QoL.
Reliable risk estimates for venous thrombosis in families with inherited thrombophilia are scarce but necessary for determining optimal screening and treatment policies.
In the present analysis, we ...determined the risk of a first venous thrombotic event in carriers of a thrombophilic defect (i.e. antithrombin-, protein C- or protein S deficiency, or factor V Leiden).
The asymptomatic carriers had been tested prior to this study in nine European thrombosis centers because of a symptomatic carrier in the family, and were followed prospectively for 5.7 years on average between March 1994 and January 2001. Annually, data were recorded on the occurrence of risk situations for venous thrombosis and events (e.g. venous thrombosis, death).
Twenty-six of the 575 asymptomatic carriers (4.5%) and seven of the 1118 controls (0.6%) experienced a first deep venous thrombosis or pulmonary embolism during follow-up. Of these events, 58% occurred spontaneously in the carriers compared with 43% in the controls. The incidence of first events was 0.8% per year (95% CI 0.5-1.2) in the carriers compared with 0.1% per year (95% CI 0.0-0.2) in the controls. The highest incidence was associated with antithrombin deficiency or combined defects, and the lowest incidence with factor V Leiden.
The incidence of venous events in asymptomatic individuals from thrombophilic families does not exceed the risk of bleeding associated with long-term anticoagulant treatment in the literature (1-3%).
In this study we examined whether low-density lipoprotein (LDL) receptor family members represent a link between blood flow characteristics and modified low-density lipoproteins involved in ...endothelial injury, a pivotal factor in atherogenesis. We demonstrated the expression of pro-atherogenic LDL receptor relative (LR11) for the first time in human coronary artery endothelial cells (HCAEC) in vitro and in vivo. Next, LR11 expression and regulation were explored in HCAEC cultured conventionally or on the inner surface of hollow fiber capillaries under exposure to shear stress for 10 days in the presence or absence of LDL. There was no LR11 expression under static conditions. When exposed to chronic low shear stress (2.5 dynes/cm²) transmembrane and soluble endothelial-LR11 were detected in high levels irrespective of the type of LDL added (carbamylated or native). In contrast, chronic high shear stress (25 dynes/cm²) inhibited the LR11-inducing effect of LDL such that transmembrane and soluble LR11 expression became non-detectable with native LDL. Carbamylated LDL significantly counteracted this atheroprotective effect of high shear stress as shown by lower, yet sustained expression of soluble and transmembrane LR11. Oxidised LDL showed similar effects compared to carbamylated LDL but caused significantly lower LR11 expression under chronic high shear stress. Medium from HCAEC under LR11-inducing conditions enhanced vascular smooth muscle cell migration, which was abrogated by the anti-LR11 antibody. Expression of LR11 depended entirely on p38MAPK phosphorylation. We conclude that coronary endothelial LR11 expression modulated by LDL and chronic shear stress contributes to atherogenesis. LR11 and p38MAPK are potential targets for prevention of atherosclerosis.
Summary
Patients with severe haemophilia A experience frequent and spontaneous bleeding, causing debilitating damage to joints and decreasing quality of life. Prophylaxis with factor VIII (FVIII) ...reduces joint damage if initiated early. Circulating FVIII levels may be influenced by endogenous von Willebrand factor (VWF), a chaperone protein that binds and stabilizes FVIII. The aim of this study was to determine whether endogenous VWF antigen (VWF:Ag) levels are correlated with FVIII pharmacokinetic (PK) parameters and clinical outcomes in patients with severe haemophilia A. Previously treated, non‐inhibitor patients in a multinational, randomized, double‐blind, Ph II study received prophylaxis with once‐weekly BAY 79‐4980 (35 IU kg−1) or thrice‐weekly recombinant sucrose‐formulated FVIII (rFVIII‐FS; 25 IU kg−1). PK parameters were evaluated at weeks 1 and 26. The number of bleeds per patient during the study was captured as part of the core efficacy endpoint. Spearman rank correlations assessed relationships of VWF:Ag levels with patient age, PK and annualized bleeding rate. Of 131 study patients (aged 13−64 years; BAY 79‐4980, n = 63; rFVIII‐FS, n = 68), 27 (21%; n = 15 and 12 respectively) were evaluable for PK assessment. Baseline VWF:Ag levels correlated with patient age (P < 0.0001). There was no significant difference in PK results between treatments; thus, PK parameters and VWF levels of all patients were analysed together. AUCnorm and T1/2 significantly increased with increased VWF:Ag (P < 0.001); clearance significantly decreased with increased VWF:Ag (P = 0.002). Annualized bleeding rate in patients treated with 3× per week rFVIII‐FS significantly correlated with VWF:Ag and age (P = 0.038 and 0.021 respectively). PK parameters as well as the clinical outcome significantly correlated with endogenous VWF:Ag. The improved clinical outcome in subjects with high VWF:Ag levels may be explained by VWF:Ag influence on FVIII PK.
We report on 21 patients with idiopathic thrombotic thrombocytopenic purpura (TTP) whose courses of disease have been followed from the respective diagnosis until now. They had a documented ADAMTS13 ...activity below 5%, a high autoantibody titer and detectable ultralarge von Willebrand factor (VWF) multimers during their episodes. The initial diagnosis was based on clinical symptoms and on laboratory parameters: thrombocytopenia, haemolytic anaemia, schistocytes and an increased LDH level. 103 acute clinical episodes of 21 TTP-patients during a time period of 30 years are described. Case histories, comorbidities and sequelae were retrospectively documented.
Although patients are consistently in a prothrombotic status, clinical acute manifestations only occur after triggering. Most common trigger factors are gastrointestinal infections and pregnancy. The relapse risk per month is 0.026; men have a higher risk for relapses (0.044) than women (0.021). Patients recover physically well, except for renal insufficiency in four cases. Nevertheless, major portion of patients suffers persistently from depression, anxiety disorders and persistent neurocognitive impairments.
A plasma-derived von Willebrand factor (VWF) concentrate with low factor VIII (FVIII) content was specifically developed to treat von Willebrand disease (VWD). Efficacy and safety were investigated ...by merging the results of two comparable protocols conducted prospectively in 5 European and 12 French centers.
Fifty patients with clinically severe VWD (72% had VWF ristocetin cofactor activity less than 10 IU dL(-1) and 46% had FVIII < 20 IU dL(-1)) were treated with the concentrate as the only therapy, except for clinical situations requiring a priming dose of FVIII to rapidly correct an intrinsic coagulation defect. A total of 139 spontaneous bleeding episodes were treated; only 53 (38%) needed a concomitant FVIII dose. Outcome was excellent or good in 89% of the episodes. Forty-four patients underwent 108 surgical or invasive procedures. Outcome was excellent or good in 95 scheduled procedures (only VWF was infused) and 13 emergency procedures (a priming FVIII dose was co-administered with the first VWF infusion). There were no thrombotic complications and none of the 18 patients with type 3 VWD developed anti-VWF or anti-FVIII antibodies.
This concentrate safely and effectively provides hemostasis in patients with clinically severe VWD.
Co‐morbidities of haemophilia, such as arthropathy and blood‐borne infections, can adversely affect the quality of life of adult patients with haemophilia. The purpose of this study was to develop ...and validate a haemophilia‐specific health‐related quality of life questionnaire for adults (HAEMO‐QoL‐A). Subjects with varying severities of haemophilia completed the HAEMO‐QoL‐A at baseline and 4 weeks. Other assessments included the SF‐36 and Health Assessment Questionnaire – Functional Disability Index (HAQ‐FDI). Two‐hundred and twenty‐one participants completed the 41‐item HAEMO‐QoL‐A covering six domains (Physical Functioning, Role Functioning, Worry, Consequences of Bleeding, Emotional Impact and Treatment Concerns) and four independent items. Internal consistency was good‐to‐excellent (Cronbach’s α‐range: 0.75–0.95). Test–retest reproducibility was good, with intraclass correlation coefficients >0.80 except for the Emotional Impact domain (0.79). Concurrent validity between the HAEMO‐QoL‐A total and subscale scores and all SF‐36 subscale scores were generally good (correlations range: 0.13–0.87). Significant correlations between the HAEMO‐QoL‐A and the HAQ‐FDI ranged from −0.14 to −0.69. There were non‐significant correlations with the Treatment Concerns subscale and with the Worry subscale. The HAEMO‐QoL‐A discriminated significantly between adults with haemophilia by severity and HIV status. The Physical Functioning subscale discriminated between patients receiving prophylactic or on‐demand therapy. The HAEMO‐QoL‐A is a valid and reliable instrument for assessing quality of life in haemophilia patients.
76 German patients suffering from thrombotic thrombocytopenic purpura (TTP) were interrogated about the prevalence of co-occurring autoimmune disorders. In order to analyze a possible association of ...TTP with the questioned diseases, a comparison of prevalence rates between the patient group and the general population has been made for each disease.
Compared to the estimated prevalence rates, the statistical analysis revealed an unexpected high occurrence of the following disorders within the patient group: Hashimoto's thyroiditis (23.5% within the patients compared to 0.7% within the general population, p<0.001), systemic lupus erythematosus (SLE) (6.5% in patients to 0.025% in the general population, p<0.001), immune thrombocytopenic purpura (ITP) (6.3% in patients to 0.02% in the general population, p<0.001), psoriasis (9.4% in patients to 2.5% in the general population, p=0.005) and celiac disease (3.1% in patients to 0.2% in the general population, p=0.007).
These findings confirm the mentioned tendency of autoimmune diseases to co-occur in one individual and argue once more for a genetic susceptibility in idiopathic TTP as well as in autoimmune disorders.
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