Intravenous methylprednisolone was started just before the convalescent plasma infusion in both cases. We did not use corticosteroids from the beginning as a routine treatment. Current guidelines recommend that systemic corticosteroids should not be given routinely for the treatment of COVID-19 due to the lack of evidence of its clinical efficacy on mortality reduction.78 However, we decided to start corticosteroids when the patients' condition rapidly deteriorated to ARDS. Methylprednisolone was administered one day and two days before the plasma infusion in case 1 and case 2, respectively. Serial laboratory and oxygenation parameters showed rapid improvement right after the corticosteroid administration even before the convalescent plasma infusion.