Endothelial injury and microvascular/macrovascular thrombosis are common pathophysiological features of coronavirus disease-2019 (COVID-19). However, the optimal thromboprophylactic regimens remain unknown across the spectrum of illness severity of COVID-19. A variety of antithrombotic agents, doses, and durations of therapy are being assessed in ongoing randomized controlled trials (RCTs) that focus on outpatients, hospitalized patients in medical wards, and patients critically ill with COVID-19. This paper provides a perspective of the ongoing or completed RCTs related to antithrombotic strategies used in COVID-19, the opportunities and challenges for the clinical trial enterprise, and areas of existing knowledge, as well as data gaps that may motivate the design of future RCTs.

Aim: Despite the similarities in the pathogenesis of the beta coronaviruses, the precise infective mechanisms of SARS-CoV-2 remain unclear. Objective: In this review, we aim to focus on the proposed theories behind the pathogenesis of SARS-CoV-2 and highlight the clinical complications related to coronavirus disease 2019 (COVID-19). Methods: We conducted a literature search in Pubmed, Scopus and Google Scholar for the relevant articles regarding clinical complications and pathogenesis of COVID-19. Results: Related articles were included and discussed. Conclusion: Respiratory system and the lungs are the most commonly involved sites of COVID-19 infection. Cardiovascular, liver, kidneys, gastrointestinal and central nervous systems are involved with different frequencies and degrees of severity.

The introduction of biologic and targeted immunomodulators is a significant breakthrough in the therapeutic area of various fields of medicine. The occurrence of serious infections, a complication of secondary immunosuppression associated with these agents, leads to increased morbidity and mortality. Implementing preventive strategies could minimize infection-related complications and improve therapeutic outcomes. The purpose of this review is to focus on current evident approaches regarding screening, monitoring, preventing (immunization and chemoprophylaxis), and management of infections in patients who are candidates for about 70 biologic and targeted immunomodulators. Recommendations are based on relevant guidelines, especially the ESCMID Study Group for Infections in Compromised Hosts (ESGICH) Consensus Document series published in 2018.