SARS-CoV2: should inhibitors of the renin–angiotensin system be withdrawn in patients with COVID-19?

Abstract
In a rapid response published online by the British Medical Journal, Sommerstein and Gräni1 pushed forward the hypothesis that angiotensin-converting enzyme (ACE) inhibitors (ACE-Is) could act as a potential risk factor for fatal Corona virus disease 2019 (COVID-19) by up-regulating ACE2. This notion was quickly picked up by the lay press and sparked concerns among physicians and patients regarding the intake of inhibitors of the renin–angiotensin–aldosterone system (RAAS) by severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infected individuals.1 In this article, we try to shed light on what is known and unknown regarding the RAAS and SARS-CoV2 interaction. We find translational evidence for diverse roles of the RAAS, which allows to formulate also the opposite hypothesis, i.e. that inhibition of the RAAS might be protective in COVID-19.