SP787PLASMA EXCHANGE AND DOUBLE FILTRATION PLASMAPHERESIS IN THE TREATMENT OF RENAL GRAFT ANTIBODY MEDIATED REJECTION

Abstract

INTRODUCTION AND AIMS: There are several methods of the rapid removal of antibodies from patient's plasma, among which are double filtration plasmapheresis (DFPP) and therapeutic plasma exchange (TPE). In the present work, our experience of implementation of these two methods is summarized. OBJECTIVE: To conduct comparative assessment of TPE and DFPP: to evaluate the efficacy of reduction of the concentrations of antibodies, the influence on biochemical parameters, hemostasis and blood concentrations of tacrolimus. METHODS: Prospective randomized study in 58 recipients with renal graft antibody mediated rejection (C4d+) was conducted. 28 recipients received treatment with DFPP method, 32 ‐ with TPE method. All patients underwent 3‐4 sessions. The cumulative effect of complete course of procedures was investigated. TPE was performed on plasmofilter with maximum pore size of 0.3 microns. During one session of TPE, 2.5±0.6 L of plasma were removed. When conducting DFPP, the similar plasmofilter was used and the separator of plasma components Cascadeflo EC‐50W was consistently included in extracorporeal circuit: maximum pore size of 0.03 nm; effective surface area of 2 m2. During single session of DFPP, 2,8±0,8 L of plasma was treated within the framework of “one way” regime or recycling (regime of thermofiltration). RESULTS: The decrease in concentrations of IgG and IgM was significantly greater when using DFPP. Thus, the preferential removal of IgM could be of the great value in acute rejection treatment. When conducting DFPP, the loss of albumin was significantly lower (p=0.01). This can be important if it is necessary to conduct the procedures for the patients with baseline hypoalbuminemia and hypotension. When conducting DFPP, the plasma replacement was not required, while during TPE abundant plasma replacement “drop for drop” or more was necessary. TPE leads to equivalent reduction of HDL and LDL. DFPP primarily reduces the concentration of LDL and thereby significantly improves the atherogenic potential of plasma. As a result of abundant plasma replacement, the platelet count, INR (international normalized ratio), APTT (activated partial thromboplastin time), fibrinogen remained within the normal range. At the same time, DFPP statistically significantly reduced the levels of fibrinogen concentration (p=0.01). Consequently, the patients with baseline deficiency of fibrinogen had the increase in bleeding risk. Both TPE and DFPP contribute to the decrease in C0 of tacrolimus in blood of about 15‐20%. In this regard, the correction of drug doses is required. Some patients had the increase in concentrations of IgG and IgM in 1‐2 days after the first and second procedures. This effect of “rebound” was observed when conducting DFPP, if less than 100% of volume of circulating plasma was processed during one procedure, and less than 70% of volume of circulating plasma were removed during conventional TPE. In this case, the effectiveness of even the whole course of treatment was low. During the procedure of perfusion of increasing doses, the efficiency was good ‐ the strong decrease in concentrations of antibodies and good clinical dynamics were achieved. CONCLUSIONS: DFPP, as well as TPE are effective methods of the treatment of humoral rejection of renal graft only in case of sufficient dose of the procedure. Due to various influence on the biochemical parameters and hemostasis, indications for TPE and DFPP can vary considerably.