ELISA kit; Epitope Diagnostics, San Diego, CA, USA) and optical density (OD) ratio for IgG was 0.586 (cut-off value 0.22). The plasma was divided into two doses and administered to the patient at 12 hours interval. Each dose was given over for 1 hour. No adverse reaction occurred after the administration of convalescent plasma.
The fever subsided, and oxygen demand decreased since day 11. The patient's condition much improved with decreased CRP and IL-6 to normal range (5.7 mg/L and < 1.5 pg