Therapeutic Plasma Exchange settings
TPE was carried out via a continuous-flow centrifugation system using the Fresenius Blood Cell Separator (Fresenius COM.TEC, Germany). Extracorporeal blood flow was maintained at 20~40 ml min-1. At the end of TPE, the blood was returned with 0.9% sodium chloride physiological solution. Fresh frozen plasma was used as volume replacement solutions. Sodium citrate (pH 5.0±0.5) was used in a 1:14 v/v ratio with blood as anticoagulant therapy.