Corticosteroid use in viral pneumonia: experience so far and the dexamethasone breakthrough in coronavirus disease-2019

Dexamethasone was shown to decrease the mortality in coronavirus disease-2019 (COVID-19) recently. Use of corticosteroids was harmful in other coronavirus infections previously. WHO recommended against routine use of corticosteroids in COVID-19. In view of these, we reviewed the evidence about the use of corticosteroids in virus-induced acute respiratory distress syndrome (ARDS). Corticosteroids are beneficial in ARDS regardless of etiology. However, they increased the mortality rate in influenza-associated ARDS. In SARS and the Middle East respiratory syndrome, corticosteroids increased the mortality, delayed the viral clearance and increased the length of hospital stay. In the case of COVID-19, the available evidence from retrospective and observational studies is inconclusive about the corticosteroid use. Low-dose therapies appear to be effective. Evidence from a randomized control study found dexamethasone is effective in decreasing mortality in severe COVID-19 cases. More studies are needed to validate the benefit of corticosteroids in COVID-19.