Derivation and external validation of the PLASMIC score for rapid assessment of adults with thrombotic microangiopathies: a cohort study
TL;DR: A seven-component clinical prediction tool, termed the PLASMIC score, was developed and found to reliably assess the pretest probability of severe ADAMTS13 deficiency, and it is shown that this scoring system is superior to standard clinical assessment in addressing the diagnostic challenge presented by thrombotic microangiopathy.
About: This article is published in The Lancet Haematology.The article was published on 2017-04-01. It has received 300 citations till now. The article focuses on the topics: Thrombotic microangiopathy & Thrombotic thrombocytopenic purpura.
Citations
More filters
TL;DR: The Eighth Edition of the JCA Special Issue seeks to continue to serve as a key resource that guides the utilization of TA in the treatment of human disease.
Abstract: The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating, and categorizing indications for the evidence-based use of therapeutic apheresis in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the Committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Seventh Edition of the JCA Special Issue continues to maintain this methodology and rigor to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Seventh Edition, like its predecessor, has consistently applied the category and grading system definitions in the fact sheets. The general layout and concept of a fact sheet that was used since the fourth edition has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of therapeutic apheresis in a specific disease entity. The Seventh Edition discusses 87 fact sheets (14 new fact sheets since the Sixth Edition) for therapeutic apheresis diseases and medical conditions, with 179 indications, which are separately graded and categorized within the listed fact sheets. Several diseases that are Category IV which have been described in detail in previous editions and do not have significant new evidence since the last publication are summarized in a separate table. The Seventh Edition of the JCA Special Issue serves as a key resource that guides the utilization of therapeutic apheresis in the treatment of human disease. J. Clin. Apheresis 31:149-162, 2016. © 2016 Wiley Periodicals, Inc.
1,691 citations
466 citations
TL;DR: An introductory tutorial on calibration measurements and calibration models for predictive models using existing R packages and custom implemented code in R on real and simulated data to help informaticians and software engineers understand the role that calibration plays in the evaluation of a clinical predictive model.
151 citations
TL;DR: Despite an increase in understandings of pathogenesis of thrombotic thromBocytopenic purpura, the approaches for initial diagnosis and management of TTP vary significantly.
110 citations
TL;DR: Recent progress in the understanding of the pathogenesis and diagnosis of, and current and potential novel therapies for, hereditary and acquired TTP are highlighted.
102 citations
References
More filters
TL;DR: A nonparametric approach to the analysis of areas under correlated ROC curves is presented, by using the theory on generalized U-statistics to generate an estimated covariance matrix.
Abstract: Methods of evaluating and comparing the performance of diagnostic tests are of increasing importance as new tests are developed and marketed. When a test is based on an observed variable that lies on a continuous or graded scale, an assessment of the overall value of the test can be made through the use of a receiver operating characteristic (ROC) curve. The curve is constructed by varying the cutpoint used to determine which values of the observed variable will be considered abnormal and then plotting the resulting sensitivities against the corresponding false positive rates. When two or more empirical curves are constructed based on tests performed on the same individuals, statistical analysis on differences between curves must take into account the correlated nature of the data. This paper presents a nonparametric approach to the analysis of areas under correlated ROC curves, by using the theory on generalized U-statistics to generate an estimated covariance matrix.
16,496 citations
4,476 citations
TL;DR: A prospective randomized trial comparing plasma exchange with plasma infusion for the treatment of thrombotic throm bocytopenic purpura finds plasma exchange is more effective than plasma infusion.
Abstract: Background. Thrombotic thrombocytopenic purpura is an uncommon disease with a high mortality rate even with current treatment. The cause of the syndrome and its optimal treatment are unknown. Although both plasma exchange and plasma infusion have been useful treatments, it is not clear which is superior. In this report we describe a prospective randomized trial comparing plasma exchange with plasma infusion for the treatment of thrombotic thrombocytopenic purpura. Methods. One hundred two patients with thrombotic thrombocytopenic purpura were randomly assigned to receive either plasma exchange or plasma infusion with fresh-frozen plasma on seven of the first nine days after entry into the trial. The total volume of plasma received by patients undergoing plasma exchange was three times that received by patients undergoing plasma infusion. All the patients also received aspirin and dipyridamole. The outcomes in the two groups were compared at the end of the first treatment cycle (day 9) and after s...
1,701 citations
TL;DR: Inhibitory antibodies against von Willebrand factor-cleaving protease occur in patients with acute thrombotic throm bocytopenic purpura, suggesting that a deficiency of this protease is likely to have a critical role in the pathogenesis of platelet thromBosis in this disease.
Abstract: Background Thrombotic thrombocytopenic purpura is a potentially fatal disease characterized by widespread platelet thrombi in the microcirculation. In the normal circulation, von Willebrand factor is cleaved by a plasma protease. We explored the hypothesis that a deficiency of this protease predisposes patients with thrombotic thrombocytopenic purpura to platelet thrombosis. Methods We studied the activity of von Willebrand factor–cleaving protease and sought inhibitors of this protease in plasma from patients with acute thrombotic thrombocytopenic purpura, patients with other diseases, and normal control subjects. We also investigated the effect of shear stress on the ristocetin cofactor activity of purified von Willebrand factor in the cryosupernatant fraction of the plasma samples. Results Thirty-nine samples of plasma from 37 patients with acute thrombotic thrombocytopenic purpura had severe deficiency of von Willebrand factor–cleaving protease. No deficiency was detected in 16 samples of plasma from ...
1,636 citations
TL;DR: In this article, the authors investigated the prevalence of von Willebrand factor-cleaving protease deficiency in patients with familial and non-familial forms of thrombocytopenic purpura and hemolytic-uremic syndrome.
Abstract: Background Thrombotic thrombocytopenic purpura and the hemolytic–uremic syndrome are severe microvascular disorders of platelet clumping with similar signs and symptoms. Unusually large multimers of von Willebrand factor, capable of agglutinating circulating platelets under high shear stress, occur in the two conditions. We investigated the prevalence of von Willebrand factor–cleaving protease deficiency in patients with familial and nonfamilial forms of these disorders. Methods Plasma samples were obtained from 53 patients with thrombotic thrombocytopenic purpura or hemolytic–uremic syndrome. Von Willebrand factor–cleaving protease was assayed in diluted plasma samples with purified normal von Willebrand factor as the substrate. The extent of the degradation of von Willebrand factor was assessed by electrophoresis in sodium dodecyl sulfate–agarose gels and immunoblotting. To determine whether an inhibitor of von Willebrand factor–cleaving protease was present, we measured the protease activity in normal ...
1,449 citations