Worrying situation regarding the use of dexamethasone forCOVID-19

摘要

The World Health Organization (WHO) recently approved the preliminary clinical trial findingson the beneficial use of dexamethasone in treating critically ill patients with coronavirusdisease 2019 (COVID-19).1 Dexamethasone reduced mortality by one-third in patients on ventilators and byone-fifth in patients receiving oxygen only, however, this benefit was not found in patientswith milder disease who did not require respiratory support.2 Dexamethasone, a synthetic corticosteroid, acts as a broad-spectrum immunosuppressorwhich has greater activity (30 times) and longer duration of action (2–3 days) than cortisone.Dexamethasone will inhibit the generation and destructive effects of cytokines and thereforeis considered useful in COVID-19-related hyperinflammation or cytokine storm. This situationis frequently observed in patients with comorbidities, including diabetes, hypertension,chronic respiratory diseases, and cardiovascular and cerebrovascular diseases, who have ahigher risk of developing severe COVID-19 with complications, such as acute respiratorydistress syndrome and multiorgan failure.3–8 Against this however,dexamethasone will also limit the protective function of T cells, hinder antibody productionof B cells, and prevent the macrophage clearance mechanism, possibly resulting in higherplasma viral load and a greater risk of secondary infections. Hence, it may only be useful forselective cases, such as in patients with severe, intubated COVID-19, and cannot be ageneralized treatment for all patients.9