Venous thrombosis in the patient with cancer

The relationship between cancer and thrombosis has been known for many years. Thrombotic risk is increased in the patient with cancer, and the diagnosis of venous thromboembolism at the time that a malignancy presents influences patient outcome. Risk evaluation, prophylaxis and treatment of venous thromboembolism are practical issues that face doctors who are dealing with these patients.http://www.sajgo.co.za/index.php/sajg

Anticoagulation therapy in diabetic patients

Diabetic patients have a high risk of developing arterial disease (coronary artery, cerebrovascular and peripheral arterial disease) and are therefore often given antiplatelet therapy. Although only retrospective studies suggest that diabetic patients are also prone to venous thrombo-embolism, many comorbid factors in the diabetic patient, such as heart failure, physical inactivity and atrial fibrillation increase the risk of venous thrombosis. A recent sub-analysis of the RECORD study examined the risk of hyperglycaemia during hip replacement, as a risk factor for postoperative venous thrombo-embolism. For these reasons, diabetic patients are also often given anticoagulant therapy.http://www.diabetesjournal.co.za

COVID-19-associated coagulopathy and antithrombotic agents—lessons after 1 year

COVID-19 is associated with a high incidence of thrombotic complications, which can be explained by the complex and unique interplay between coronaviruses and endothelial cells, the local and systemic inflammatory response, and the coagulation system. Empirically, an intensified dose of thrombosis prophylaxis is being used in patients admitted to hospital with COVID-19 and several guidelines on this topic have been published, although the insufficiency of high quality and direct evidence has led to weak recommendations. In this Viewpoint we summarise the pathophysiology of COVID-19 coagulopathy in the context of patients who are ambulant, admitted to hospital, and critically ill or non-critically ill, and those post-discharge from hospital. We also review data from randomised controlled trials in the past year of antithrombotic therapy in patients who are critically ill. These data provide the first high-quality evidence on optimal use of antithrombotic therapy in patients with COVID-19. Pharmacological thromboprophylaxis is not routinely recommended for patients who are ambulant and post-discharge. A first ever trial in non-critically ill patients who were admitted to hospital has shown that a therapeutic dose of low-molecular-weight heparin might improve clinical outcomes in this population. In critically ill patients, this same treatment does not improve outcomes and prophylactic dose anticoagulant thromboprophylaxis is recommended. In the upcoming months we expect numerous data from the ongoing antithrombotic COVID-19 studies to guide clinicians at different stages of the disease.http://www.thelancet.com/haematologyam2022Medical Oncolog

COVID-19 vaccines : adverse events following immunisation

Patients rely on healthcare providers as their most credible and frequent source of vaccine information. It is therefore crucial that healthcare providers are informed and have evidence-based, objective and clear guidance on vaccine efficacy and specific adverse events following immunisation (AEFI). Reported serious AEFIs are extremely rare for the COVID-19 vaccines. This article discusses the main AEFIs attributed to COVID-19 vaccines, including neurological complications of Guillain-Barré syndrome (GBS) and acute transverse myelitis (ATM), thrombosis; cardiac complications, including myocarditis, pericarditis and cardiomyopathy; and allergic reactions such as anaphylaxis, urticaria and skin rashes. The benefits of COVID-19 vaccination outweigh the risks; however, it is important that healthcare providers are aware of the risks and know how to recognise and manage them.https://journals.co.za/journal/caciam2023Paediatrics and Child Healt

A descriptive investigation of the ultrastructure of fibrin networks in thrombo-embolic ischemic stroke

Stroke is one of the leading causes of death worldwide. Formation of a fibrin clot is controlled by a group of tightly regulated plasma proteases and cofactors and a change in the fibrin fiber formation causes an alteration in clot morphology. This plays an important role during thrombotic events. In the current study we investigated the ultrastructure of fibrin networks from fifteen ischemic stroke patients by using scanning electron microscopy. Clot morphology was investigated with and without the addition of human thrombin to the platelet rich plasma. Previously it was shown that, when studying the ultrastructure of fibrin networks, the addition of thrombin is necessary to form an expansive, fully coagulated layer of fibers. Results from the addition of thrombin to the plasma showed thick, matted fibrin fibers and a net covering some of the major fibers in stroke patients. Typical control morphology with major thick fibers and minor thin fibers could be seen in some areas in the stroke patients. In stroke patients, without the addition of thrombin, a matted fibrin network still formed, indicating that the factors responsible for the abnormal fibrin morphology are present in the circulating plasma and is the cause of the observed matted, layered morphology. This is not present in healthy individuals. From the results obtained we suggest that this changed morphology might be useful in a screening regime to identify the possibility of a stroke or even to follow the progress of stroke patients after treatment.http://link.springer.com/journal/11239hb2017Anatomy and PhysiologyNeurolog

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements