Virus Removal and Eradication by Modified Double Filtration Plasmapheresis Decreases Factor XIII Levels

Factor XIII (FXIII) deficiency increases the chance for pathological bleeding, but this disorder cannot be detected by routine laboratory tests. Virus removal and eradication (VRAD, the trademark of Asahikasei Kuraray Medical) by double filtration plasmapheresis (DFPP) is an effective technique used to eradicate the hepatitis C virus in people afflicted with the disease. We have previously reported that DFPP significantly reduced FXIII in those undergoing this treatment. VRAD is a modified type of DFPP with a larger pore size of the second filter compared to conventional DFPP. Because VRAD may have similar effects on FXIII levels, we investigated the kinetics of FXIII during the course of VRAD therapy. A retrospective, observational study of the patients who underwent VRAD between July 2008 and May 2009 was performed. Reduction ratios and sieving coefficients of FXIII and other marker proteins were examined. FXIII levels were decreased to 20% after each therapy. The reduction ratio and sieving coefficients of FXIII were between those of IgG (0.4–0.5) and LDL cholesterol (0.35). Similar to other blood purification therapies, therapeutic intensity, molecular weight, and half life are crucial factors for solute removal. Although the coexistence of liver disease might modify the course of FXIII during VRAD, the therapy itself effectively reduced FXIII levels. FXIII levels should be closely monitored during VRAD in order to reduce the chance of negative clinical sequelae.