In Vitro and in Vivo Studies of Erythropoiesis during Continuous Ambulatory Peritoneal Dialysis

Abstract

In order to understand the effect of CAPD on the anemia of chronic renal failure, we studied the behaviour of some hematological parameters and of the colony-formation capacity of bone marrow cells in in vitro cultures in patients undergoing this therapy. Our studies showed a rise in hematocrit, hemoglobin and reticulocyte values, which showed a significant correlation with a recovery of the erythroid cell proliferative activity. Since serum erythropoietin levels do not change, the improvement of bone-marrow function appears to be due to a better clearance (by CAPD) of substances, which inhibit the response of bone marrow to the erythropoietin.

Clinical Applications of Iron Management in Peritoneal Dialysis Patients

“…In addition, we have seen an increase in RBC mass and a decrease in plasma volume (12,24). This may be explained by the more efficient removal of middle-molecular-weight molecules with CAPD (13,22,24,25), which may act as inhibitors of erythropoiesis (16). Adding sera from uremic nondialyzed patients leads to inhibition of formation of CFU-E and erythroid burst-forming units (26).…”

“…Due to the recovery of proliferative activity of the erythroid cells, serum ferritin and iron levels will fall. Therefore, the early use of oral iron supplementation is warranted (16).…”

“…Many authors have shown that patients on continuous ambulatory peritoneal dialysis (CAPD) have better responses to EPO, less severe anemia, and lower iron loss (and thus lower iron requirements) when compared to the hemodialysis (HD) population. Theories include removal of middle‐molecular‐weight inhibitors of erythropoiesis ( 13–15), a liberalized dietary intake, elimination of exposure to bioincompatible membranes, better volume and metabolic control, and absence of trauma to RBCs ( 16, 17) as the blood traverses the tubing, dialyzer, and pumps of an HD system. Another consideration is that when poorly biocompatible dialysis membranes are used in HD, mononuclear cells are stimulated to produce and release tumor necrosis factor–alpha (TNF‐α).…”

Anaemia of renal failure: Differences between continuous ambulatory peritoneal dialysis and haemodialysis

“…[1][2][3][4][5] A lower degree of anaemia in CAPD patients than in HD patients has been documented in numerous studies. [6][7][8][9][10] It has been suggested that CAPD facilitates increased erythropoietin production compared to haemodialysis, as well as a better depuration of toxic metabolites inhibiting erythropoiesis. [6][7][8][9][10][11][12] However, information regarding the influence of iron metabolism on differences in the severity of anaemia between CAPD and HD patients is limited.…”

“…[6][7][8][9][10] It has been suggested that CAPD facilitates increased erythropoietin production compared to haemodialysis, as well as a better depuration of toxic metabolites inhibiting erythropoiesis. [6][7][8][9][10][11][12] However, information regarding the influence of iron metabolism on differences in the severity of anaemia between CAPD and HD patients is limited. This is a particularly relevant aspect given the well-known benefits of recombinant human erythropoietin (r-HuEPO) in the treatment of renal anaemia and that iron supplementation is mandatory in patients with r-HuEPO hyporesponsiveness.…”