MO663: No Translocation of Intact Intestinal Bacteria During Intermittent Dialysis Therapies

Abstract

Abstract BACKGROUND AND AIMS Accumulating evidence shows that online post-dilution haemodiafiltration (HDF), especially when a high convection volume is achieved, is associated with a lower mortality risk than haemodialysis (HD) [1]. The mechanism behind this effect, however, is unclear. In this respect, a superior intradialytic organ perfusion and hence, less intestinal tissue damage, permitting the transfer of bacteria from the gut to the blood, might play an important role. Therefore, we assessed whether differences exist in the intradialytic translocation of intact bacteria between four dialysis modalities. METHOD A randomized cross-over trial was performed (NCT03249532, ClinicalTrials.gov) in 11 prevalent dialysis patients, who were exposed to four dialysis strategies: HD with standard dialysate temperature (Td) 36.5°C and cool (Td 35.5°C) dialysate, and HDF with a high (≥23 L/1.73 m2/session) and low (15 L/1.73 m2/session) convection volume. Microbial DNA (mDNA), soluble CD14, high-sensitivity CRP and IL-6 receptor were measured during each modality, as secondary endpoints of this study. Quantitative assessment of mDNA was performed by 16S-23S interspace profiling after DNA isolation [2, 3]. In the current analysis, the quantitative difference in circulating mDNA between modalities was investigated. In addition, differences in the acute phase reaction (APR), as measured by soluble CD14, high-sensitivity CRP and IL-6 receptor and potential relations between mDNA and the APR were analysed. RESULTS DNA of intact bacteria could not be demonstrated in blood samples of the patients in any dialysis strategy. Yet, in all modalities a similar increase in IL-6 receptor, high-sensitivity CRP and soluble CD14 was observed (pre- versus post-dialysis: P-values <.05) (Figures 1A-B). CONCLUSION i) The appearance of DNA from intact bacteria in the blood of dialysis patients could not be demonstrated, despite the use of a sensitive state-of-the-art technique, which is free from contamination by human DNA; ii) during all modalities a comparable and significant APR was observed; iii) hence, the intradialytic APR does not seem to result from translocated intact bacteria.