End stage renal disease has an early and continuous detrimental effect on regulatory T cells.

End stage renal disease (ESRD) is followed by disturbed adaptive immunity, together with alterations in T cell subsets, including CD4+CD25+FoxP3+ cells (Tregs). In the present study, we assessed the effect of haemodialysis (HD) on the Treg population. CD3+CD4+, CD3+CD8+ and CD4+CD25+FoxP3+ cells were estimated by flow cytometry in 142 ESRD patients (45 ESRD-preHD, 97 on HD) and 30 healthy controls (HC). Patients on HD were classified into three groups according to time on dialysis (HD vintage - HDV): A  5 years on HD. The mean age of patients on HD (M/F 53/44) was 54.8 ± 14 years and the median HDV 58 (78) months. We observed a significant progressive reduction in the percentage and count of lymphocytes (p  5 years on HD. Total lymphocytes and Tregs were significantly different among the three vintage groups (Kruskal-Wallis H test, p < .001, p < .001 respectively). CD3+CD4+ and CD3+CD8+ cells were also significantly affected (p < .001 and p = .001, respectively), after at least 2 years of HD. Tregs show prompt and significant reduction at the pre-dialysis stage, and continue to decrease gradually even after long-term HD, in a context of total lymphocyte reduction.