Coagulopathy and thromboembolism in children with COVID-19 - pathophysiology, thrombotic risk, clinical manifestations, and management

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since the beginning of the pandemic, it has been generally accepted that children infected with SARS-CoV-2 either stay asymptomatic or present benign symptoms. Yet SARS-CoV-2 is widely known to cause serious consequences in children and adolescents. Complications may develop during infection, several weeks afterwards, or in the course of multisystem inflammatory syndrome in children (MIS-C). MIS-C manifests with fever, gastrointestinal, cardiovascular and/or neurological symptoms. Moreover, thromboembolism is a relatively common complication of COVID-19 and MIS-C. The purpose of this work was to review current reports on thromboembolic complications among children who underwent SARS-CoV-2 infection. Among the published cases of MIS-C, thromboembolic incidents ranged from 1.4% to 6.5%, taking the form of a brain infarct, deep vein thrombosis, pulmonary embolism, or splenic infarct. Several mechanisms leading to thrombosis in COVID-19 in children are considered. The development of acute infection in the lungs results in local clot formation in the pulmonary microcirculation, leading to perfusion disturbances. ADAMTS13 activity is also mildly reduced in patients infected with SARS-CoV-2, increasing the risk of microthrombosis. COVID-19-associated coagulopathy is characterized by elevated D-dimers and fibrinogen levels. Significantly increased D-dimers probably represent activation of coagulation caused by viremia and cytokine storm, as well as possible organ dysfunction. The treatment of thromboembolism in children includes low and high molecular weight heparins and acetylsalicylic acid. Pediatricians should be aware of the possible multiple complications associated with COVID-19 in children, including thromboembolic incidents. Copyright © 2022 Sciendo. All rights reserved.

Antimicrobial prophylaxis in adults and children undergoing hematopoietic cell transplantation: 2021 Polish recommendations

Infections are still one of the most common causes of death after hematopoietic cell transplantation (HCT). Antimicrobial prophylaxis plays a crucial role in decreasing non-relapse mortality after HCT. The objective of this guideline paper was the presentation of current recommendations of antimicrobial prophylaxis for children and adults after hematopoietic cell transplantation, prepared in cooperation with Polish scientific hematological societies. Recommendations were prepared by the working group and finally approved by all 23 Polish transplant centers for children and adults. Existing (European Conference on Infections in Leukemia (ECIL) and European Society of Blood and Marrow Transplantation (EBMT) guidelines, as well as the results of a survey performed among all Polish transplant centers, were the background material for the working group. Recommendations are presented in sections dedicated to antibacterial prophylaxis, antifungal prophylaxis, antiviral prophylaxis, as well as prophylaxis of toxoplasmosis and infections with Pneumocystis jiroveci. Recommendations on the principles of vaccination against COVID-19 are provided based on the state of knowledge in September 2021. A section on guidelines of environmental prophylaxis is also presented.