#4983 THE UNEXPECTABLE BALANCE OF PROINFLAMMATORY CELLS IN PERITONEAL DIALYSIS PATIENTS

Abstract

Abstract Background and Aims Chronic kidney disease (CKD) is a complex and heterogeneous disease and is increasingly becoming a global public health concern. It is is characterized by a persistent inflammation state which appear to be caused by cytokines, grown factors and hormones. Peritoneal dialysis (PD) accounts for 9% of all kidney replacement therapy (KRT) and over time, some changes are expected to occur in the peritoneal membrane mainly due to exposure to PD solutions, infectious processes and non-infectious complications. This inflammatory process is poorly understood and needs further clarification, but Th17 cells and Th1 cells seem to be involved. Therefore, we aimed to quantify the frequency of peripheral immune cells and the concentration of IL-17A in peripheral blood (PB) and peritoneal effluent (PE) and compare to a healthy control group. Method In a cross-sectional study of 26 PD patients and 10 healthy, age and sex-matched controls we evaluated PB and PE frequencies of T lymphocytes, T CD4, T CD8 and Th1 cells by flow cytometry as well as IL-17 concentrations using enzyme-linked immunosorbent assay. Comparisons were performed between PD patients and controls and between the different groups of PD patients according to PD modality, number of exchanges, dialysate tonicity, extraneal use, infusion and daily total volumes, type of peritoneal transport and volume indexes. Statistical analyses were performed using the SPSS statistics version 26. Results Table 1 summarizes the main characteristics of PD patients and controls. Overall, in comparison with the control group, the frequency of Th1 cells in PB of PD patients was significantly lower (P = 0.001). On the other hand, frequency of Th1 cells substantially expanded in the PE, as compared to the PB (P = 0.001). PD patients also presented lower Th17 cells frequencies (P = 0.061) and those prescribed Extraneal had the lowest frequencies of Th17 (P = 0.030). IL-17A concentration was significantly higher in PE vs PB of PD patients (P = 0.012). Finally, the frequency of total lymphocytes in high PD transporters was significantly higher in comparison with high-average transporters (P = 0.021). Conclusion In our cohort, PE presented high concentrations of proinflammatory cells and cytokines. Th1 cells rather than Th17 cells were increased, pointing to a predominant cytolytic activity but IL-17 was also increased. Treatment with Extraneal associated with a lower frequency of these cells, somehow counterbalancing the inflammatory millieu associated with high glucose concentrations.