MO876: B Lymphocyte Subpopulations in End-Stage Renal Disease Patients Undergoing Renal Replacement Therapy: Does the Method Affect the Phenotype?

Abstract

Abstract BACKGROUND AND AIMS End-stage renal disease (ESRD) patients are considered as immunocompromised, and infections contribute greatly to their morbidity and mortality. This study focuses on the changes of B lymphocyte subpopulations in pre- and post- renal replacement therapy ESRD patients and the potential differences between haemodialysis and peritoneal dialysis. METHOD Using flow cytometry, B cells (CD19+) and their subsets B1a (CD19 + CD5+), naive (CD19 + CD27−), memory (CD19 + CD27+), (CD19 + BAFF-R+) and (CD19 + IgM+), were quantified in the peripheral blood of 40 pre-dialysis patients. IgG, IgA and IgM serum levels and apoptotic lymphocytes and b lymphocytes were also measured, and the measurements were repeated 6 months after the initiation of renal replacement therapy. The patients were allocated to haemodialysis (22patients, M/F 10/12, age 64,1 ± 9,8) and peritoneal dialysis (18 patients, M/F 11/11, age 56,4 ± 15,6). Exclusion criteria were age < 18 or >75 years, active autoimmune or chronic inflammatory disease, medical history of malignancy, corticosteroids or immunosuppresive treatment for the last 12 months. RESULTS There were no statistically significant difference between the two groups concerning the aforementioned variants pre dialysis. Collectively, ESRD patients showed no statistically significant alterations after the initiation of dialysis concerning the B cells phenotype, lymphocyte apoptosis and Immunoglobin serum levels, with the notable exception of B1a cells, which presented a decrease (3.6 ± 4.9 μ/L versus 1.6 ± 2.5 μ/L, P = 0.022). There seem to be no particular differences between the two methods either, with the exception of WBC count (6574 ± 1519 μ/L versus 8325 ± 2541 μ/L, P = 0.014) and apoptotic B lymphocytes (2 ± 2.4 μ/L versus 4.5 ± 3.9 μ/L, P = 0.02), which were lower in the peritoneal dialysis patients. Lastly there seemed to be no differentiation between the two methods concerning the percentage change of B lymphocytes subpopulations, lymphocyte apoptosis and IgG, IgM and IgA serum levels. CONCLUSION The changes that the uremic milieu causes in ESRD patients concerning their humoral Immunity do not reverse with the initiation of renal replacement therapy. Furthermore, with the exception of B cells apoptosis and WBC count, there is no significant difference between haemodialysis and peritoneal dialysis.