Markers of bone metabolism in hemodialyses and hemodiafiltration.

Renal osteodystrophy is a common complication of chronic renal failure and renal replacement therapy. The purpose of the study was to assess whether hemodialysis (HD) or hemodiafiltration (HDF) affects bone turnover. In all, 45 HD and 17 HDF patients were evaluated with respect to bone metabolism markers. We assessed PTH; markers of bone formation-alkaline phosphatase and its bone isoform, osteocalcin; markers of bone resorption- PICP, ICTP; Ctx; beta2-microglobulin; and urinary DPD. BMD were determined for femoral neck and lumbar spine (L2-L4) using DEXA. Hemodialyzed patients had lower calcidiol, calcitriol, and BMD in the femur neck, and higher phosphate, Kt/V, residual renal function, venous pH, osteocalcin, ALP, bALP, DPD, beta2-microglobulin, ICTP, Ctx, osteoprotegerin, and RANKL than patients on HDF. HDF seems to ameliorate bone metabolism in comparison with HD. Bone turnover in end-stage renal failure might be affected to some extent by the choice of renal replacement therapy.