31 research outputs found
A systematic approach for the identification of novel, serologically reactive recombinant Varicella-Zoster Virus (VZV) antigens
<p>Abstract</p> <p>Background</p> <p>Varicella-Zoster virus causes chickenpox upon primary infection and shingles after reactivation. Currently available serological tests to detect VZV-specific antibodies are exclusively based on antigens derived from VZV-infected cells.</p> <p>Results</p> <p>We present a systematic approach for the identification of novel, serologically reactive VZV antigens. Therefore, all VZV open reading frames were cloned into a bacterial expression vector and checked for small scale recombinant protein expression. Serum profiling experiments using purified VZV proteins and clinically defined sera in a microarray revealed 5 putative antigens (ORFs 1, 4, 14, 49, and 68). These were rearranged in line format and validated with pre-characterized sera.</p> <p>Conclusions</p> <p>The line assay confirmed the seroreactivity of the identified antigens and revealed its suitability for VZV serodiagnostics comparable to commercially available VZV-ELISA. Recombinant ORF68 (gE) proved to be an antigen for high-confidence determination of VZV serostatus. Furthermore, our data suggest that a serological differentiation between chickenpox and herpes zoster may be possible by analysis of the IgM-portfolio against individual viral antigens.</p
Characteristics and Outcomes of Patients With Cerebral Venous Sinus Thrombosis in SARS-CoV-2 VaccineâInduced Immune Thrombotic Thrombocytopenia
Importance: Thrombosis with thrombocytopenia syndrome (TTS) has been reported after vaccination with the SARS-CoV-2 vaccines ChAdOx1 nCov-19 (Oxford-AstraZeneca) and Ad26.COV2.S (Janssen/Johnson & Johnson).
Objective: To describe the clinical characteristics and outcome of patients with cerebral venous sinus thrombosis (CVST) after SARS-CoV-2 vaccination with and without TTS.
Design, setting, and participants: This cohort study used data from an international registry of consecutive patients with CVST within 28 days of SARS-CoV-2 vaccination included between March 29 and June 18, 2021, from 81 hospitals in 19 countries. For reference, data from patients with CVST between 2015 and 2018 were derived from an existing international registry. Clinical characteristics and mortality rate were described for adults with (1) CVST in the setting of SARS-CoV-2 vaccine-induced immune thrombotic thrombocytopenia, (2) CVST after SARS-CoV-2 vaccination not fulling criteria for TTS, and (3) CVST unrelated to SARS-CoV-2 vaccination.
Exposures: Patients were classified as having TTS if they had new-onset thrombocytopenia without recent exposure to heparin, in accordance with the Brighton Collaboration interim criteria.
Main outcomes and measures: Clinical characteristics and mortality rate.
Results: Of 116 patients with postvaccination CVST, 78 (67.2%) had TTS, of whom 76 had been vaccinated with ChAdOx1 nCov-19; 38 (32.8%) had no indication of TTS. The control group included 207 patients with CVST before the COVID-19 pandemic. A total of 63 of 78 (81%), 30 of 38 (79%), and 145 of 207 (70.0%) patients, respectively, were female, and the mean (SD) age was 45 (14), 55 (20), and 42 (16) years, respectively. Concomitant thromboembolism occurred in 25 of 70 patients (36%) in the TTS group, 2 of 35 (6%) in the no TTS group, and 10 of 206 (4.9%) in the control group, and in-hospital mortality rates were 47% (36 of 76; 95% CI, 37-58), 5% (2 of 37; 95% CI, 1-18), and 3.9% (8 of 207; 95% CI, 2.0-7.4), respectively. The mortality rate was 61% (14 of 23) among patients in the TTS group diagnosed before the condition garnered attention in the scientific community and 42% (22 of 53) among patients diagnosed later.
Conclusions and relevance: In this cohort study of patients with CVST, a distinct clinical profile and high mortality rate was observed in patients meeting criteria for TTS after SARS-CoV-2 vaccination.info:eu-repo/semantics/publishedVersio
2021 Update of the International Council for Standardization in Haematology Recommendations for Laboratory Measurement of Direct Oral Anticoagulants
International audienceIn 2018, the International Council for Standardization in Haematology (ICSH) published a consensus document providing guidance for laboratories on measuring direct oral anticoagulants (DOACs). Since that publication, several significant changes related to DOACs have occurred, including the approval of a new DOAC by the Food and Drug Administration, betrixaban, and a specific DOAC reversal agent intended for use when the reversal of anticoagulation with apixaban or rivaroxaban is needed due to life-threatening or uncontrolled bleeding, andexanet alfa. In addition, this ICSH Working Party recognized areas where additional information was warranted, including patient population considerations and updates in point-of-care testing. The information in this manuscript supplements our previous ICSH DOAC laboratory guidance document. The recommendations provided are based on (1) information from peer-reviewed publications about laboratory measurement of DOACs, (2) contributing author's personal experience/expert opinion and (3) good laboratory practice
Evaluation of Biomarkers for the Prediction of Venous Thromboembolism in Ambulatory Cancer Patients
Background: Venous thromboembolism (VTE) is a common complication of cancer. This study aimed to evaluate immature platelet fraction (IPF), mean platelet volume (MPV), P-selectin, D-dimer, and thrombin generation (TG) as predictive biomarkers for VTE and further the improvement of existing risk assessment models (RAMs). Methods: A prospective, observational, exploratory study was conducted on ambulatory cancer patients with indication for systemic chemotherapy. Baseline RAMs included the Khorana-, Vienna Cancer, Thrombosis-, Protecht-, ONKOTEV-, and Catscore. IPF, MPV, P-selectin, D-dimer, and TG were analysed at baseline and 3-month follow-up. Results: We enrolled 100 patients, of whom 89 completed the follow-up. Frequent tumour types were breast (30%), gastric (14%), gynaecological (14%), and colorectal (14%) cancer. Ten of the 89 patients (11.2%) developed VTE. The highest VTE rate was observed in patients with cholangiocarcinoma (3/5; 60%). Baseline D-dimer levels but not IPF, MPV, or P-selectin were associated with the risk of developing VTE (HR 6.9; p = 0.021). None of the RAMs showed statistical significance in predicting VTE. Peak thrombin and endogenous thrombin potential were lower in patients who developed VTE. Biomarker changes between baseline and follow-up were not associated with VTE risk. Conclusions: VTE risk was well predicted by baseline D-dimer levels. Adding D-dimer could improve existing RAMs to better identify patients who may benefit from primary VTE prophylaxis. The VTE risk among patients with cholangiocarcinoma should be further evaluated