Conclusion
From this study, we conclude as follows: (i) circulating mDNA could not be demonstrated; (ii) in the crude analysis, a similar APR was noted in all modalities, individual markers remained stable or declined after correction for hemoconcentration; and (iii) because neither bacterial translocation nor an APR was observed in either modality, it is highly unlikely that the superior survival of HV-HDF is explained by a superior preservation of gut integrity.
Methods
Forty patients were cross-over randomized to standard (hemodialysis [HD]) (S-HD), cool HD (C-HD), and HDF (low-volume [LV] and HV, convection volume (CV) of 15 L and ≥ 23 L per session, respectively), each for 2 weeks. Quantitative assessment of microbial DNA (mDNA) in blood was performed before and after dialysis by 16S to 23S interspace profiling after DNA isolation. The intradialytic acute phase response (APR) was evaluated by high-sensitivity C-reactive protein (hs-CRP), interleukin-6 receptor (IL-6R), soluble CD14 (sCD14), and vascular-cell-adhesion molecule-1 (VCAM-1). Differences between modalities were primary objectives.
Results
mDNA was absent from all samples. IL-6R, sCD14, and VCAM-1 increased equally in all modalities (median increase: 12.5%, 14.0%, 14.8%, respectively; P < 0.05). hs-CRP increased only in C-HD and HV-HDF (median increase: 12.6%, P < 0.05). After correction for hemoconcentration, most APR markers decreased (median: sCD14, -11.3% and VCAM-1, -14.4% in all modalities; IL-6R, -13.4% in C-HD, LV-HDF, and HV-HDF; P < 0.05). hs-CRP only decreased in C-HD (-13.5%, P = 0.004).